AN INSTITUTION NOILNLILSNI NVINOSHLINS S3J!I1YVYSIT LIBRARIES SMITHSONIAN INS es rs Th ins S lh a ¥ hi ee) — w a w — es) yD 2 D = 2 = Wi sass = e Ee i r, Bcd op) > as a z 4 z 5 z ef Ns Saleve alt LIBRARIES SMITHSONIAN INSTITUTION NOILALILSNI NVINOSHLIWS SJI2 = ; = = aie = i it < z | 3 YG, = : ; 2: §%,% q ) 8 zs 8 z 8 Gf; 2 é = E 2 = 2G fv’ EC Zz > = \ > = ~ >’ = . 4 Zo. wo Pi wn Phiee 2 o S AN_INSTITUTION NOILNLILSNI_NVINOSHLINS S3I1YVY@IT LIBRARIES SMITHSONIAN INST Z s Zz Ne Z 4 > | (op) eo we ioe) (ap) Sa. oc = oc = o a 3 5 z 5 a. a a a ie cap hig = oe = } NS S3IYWHRSIT L!ISRARIES SMITHSONIAN INSTITUTION NOILOALILSNI NVINOSHLINS S39] o a - mee) ° ow (a) ras > age > fe AM D m ” m 2) pa w” Zz o z 7 D z on z AN INSTITUTION, | OT eee ee luvadd youl B RAR | ES SMITHSONIAN _ INST Soe eee = = gm Ce: < | Pus SY = x = =) NS 4 = ) B URN GB 2 Bs BRS 2 y J= NY 3 : a =~ 2 : = py > = oe = " * . 7 a w” ae = fg NS $3 lYVYusia_ LIBRAR] ES SMITHSONIAN INSTITUTION NOILOLILSNI_NWINOSHUINS 52 I ul a uu a Le: F* ae @ ee 4 = - < z < = & : : : : : : : ae fe) Ze re) = oO = > = > = > a = ‘Y ae eu a 1% ANS WY rn 2 A ede Se m 2 mn NS aleve aI _ LIBRARIES SMITHSONIAN - _ ee Ae = ; < = z = < = = = = = 2 Zz +4 4 \ oo 8 5 fe} a ~ O = @ \ ae n “”) ee a a : O i fe) Ba re) < 9 A 2 Ee 2 = 2 = 2y% > = \ > = x =) = 5 w” 2 ” : Zz w” z AN INSTITUTION NOILNLILSNI_NVINOSHLINS SaldVva alt LIBRARIES SMITHSONIAN INST i o ! Bs pe mo a a Z nef z i ' * Te) UY. he : : z 4 = Yin, — Oz | oN \ ff a © ; j Dacha wed = om Oo ae. i fe) a of z os = ih as Po Be 2 VS Saluvddiy LIBRARI Ea SM FHSON aN INS NOILALILSNI > z= 2 fez a — O — ace : : : : : : : Pe) = = = Wy > re > ‘ > = ah ” za rz a Ee o m ot m @ m o Pehbow! NVINUSHLIWS SSAIOVGRI! EIONANRIECS OMIDAOUNIAN INOTIIPULIOUN SMa inte i & ra iz Zz (ary Fue L Ps oO ao oO Pry ——— (@) be ~ 1 po) > 20 > tas = = - z = = - m ot m 2 , m > Ww — [op = 1ep) = INSTITUTION NOILNLILSNI NVINOSHLINS SaItuvVyudIT_LIBRARI wo a ” = n = ss = < = V4 < = } = = 5 = 4 iy, 5 =e Oo i 2 8 Yh g : = a Z thy: oo = E \ > = ~ > = > = ie Zz a ap 2 7) 2 we HINLILSNI_NWINOSHLINS | S43 IYVYEIT LIBRARIES SMITHSONIAN INSTITUTION # 2 Zz bs ' Zz uw a) = w” MM Uy Ww es “1 . = = Yim,” 0c = : ag ad = : > > w” Fa ae) * Zz ra BRARIES SMITHSONIAN INSTITUTION NOILNLILSNI LIBRARIES LIBRARIES NOILNILILSNI Salu¥vudiIt LIBRARIES INSTITUTION NOILNLIL BRARIES SMITHSONIAN INSTITUTION NOILOLILSNI NVINOSHLINS SAIYVUdIT LIBRARI SJIUVUGIT LIBRARIES SMITHSONIAN INSTITUTION NOILALILSNI INSTITUTION NOILALILSNI Sa1uvydl INSTITUTION S3I1Y¥Vudl w z= w rd wn = ‘" = < = sy < = < 7 4 Sj LG ‘ : E 2 GY 2 z 5 aS : 8 Ue ? g 2 oS zZ = a0 hy ae = = N > = >’ s >’ Ss WSN “” za ” = ” NVINOSHLIWS LIBRARIES SMITHSONIAN INSTITUTION NOILNLIL NOILNLILSNI NOILNLILSNI NOILNLILSNI BRARIES SMITHSONIAN INSTITUTION NOILQALILSNI NVINOSHLINS S3!lyu¥yvudiIT LIBRARI J;4YVYGIT LIBRARIES jIUVUGIT_ LIBRARIES JiUVUGIT LIBRARIES ISTITUTION STITUTION STITUTION a i Oh my . J is i] 4 i) = } i 1 } it ie t ~~ ~ —~ ' _ \ » o™, ’ | => z “ 4 t ~ ms i ( ' . : Ver i i ‘ ( vs ’ ny { ‘4 +} hi ‘ r ‘ Aa} { { ’ | i ; JOURNAL AND PROCEEDINGS OF THE ROYAL SOCIETY OF NEW SOUTH WALES PARTS |- 4 VOLUME 10l 1967-68 PUBLISHED BY THE SOCIETY, SCIENCE HOUSE, GLOUCESTER AND ESSEX STREETS, SYDNEY Royal Society of New South Wales OFFICERS FOR 1967-1968 Patrons His EXCELLENCY THE GOVERNOR-GENERAL OF THE COMMONWEALTH OF AUSTRALIA THE RIGHT HONOURABLE LORD CASEY, P.c., G.C.M.G., C.H., D.S.0., M.C., K.St.J. His EXCELLENCY THE GOVERNOR OF NEW SOUTH WALES SIK RODEN CUTLER): V-cC:, K:G:M:G., (C.B.E. President ANGUS H. LOW, ph.p. Vice-Presidents ALAN A. DAY, pPh.p. W. H. G. POGGENDOREE; sisemer: IK. J. W. LE PEVINE, biSc:, F.R:Si, 7h. AbAe A EV OISEY, p.sc. Honorary Secretaries J. L. GRIPPITA, &.A., Msc. Ay (REICHEL, ph.D:., M.Se; Honorary Treasurer H. F. CONAGHAN, m.sc. Members of Council R.Ay BURG, AS-T.C, D. B. LINDSAY, B.Sc... M.A.) Pll: J.C. CAMERON, M.a.,B.Sc. (Edin.) D.I.c. J. W. G. NEUHAUS? ese: R. J. GRIFFIN, B.sc: J. P. POLLARD, pip-App:chem: T. E. KITAMURA, B.aA., B.Sc.Agr. M. J. PUTTOCK, 38 7sc. (eng.), A-tnstae. M. KRYSKO v. TRYST (Mrs.), B.sc., Grad-Dip. W. H. KOBERTSON, Bsc. NOTICE The Royal Society of New South Wales originated in 1821 as the ‘‘ Philosophical Society of Australasia ”’ ; after an interval of inactivity it was resuscitated in 1850 under the name of the “ Australian Philosophical Society ’’, by which title it was known until 1856, when the name was changed to the ‘‘ Philosophical Society of New South Wales’’. In 1866, by the sanction of Her Most Gracious Majesty Queen Victoria, the Society assumed its present title, and was incorporated by Act of Parliament of New South Wales in 1881. - : JOURNAL AND PROCEEDINGS ee : oe a OF THE ROYAL SOCIETY. & OF NEW SOUTH WALES» ss CONTENTS The Livetsidge: Leste ic ~ Organic Metals ? 2 the Electrical Conductance of {Organic Solids. L. E. 2. 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LYONS Professor of Physical Chemistry, University of Queensland, Brisbane, Australia Introduction This paper discusses electrical conduction in organic solids, leaving aside the spectral and photo phenomena in which I have been greatly interested for a number of years and omitting also the organic superconductivity recently discussed by Little (1964). Let us ask: How nearly can the electrical conductivity of an organic material be made to approach values typical of metals ? This question at the moment is partly but not completely answered. Therefore I hope that the discussion tonight will encourage research in what in the last few years has become a very active front in the scientific advance ; thus may I fulfil Archibald Liversidge’s aim in establishing this lectureship, with the award of which the Royal Society of New South Wales has honoured me this year: my gratitude goes to Liversidge now just as it did when I entered the University of Sydney with a Liversidge scholarship. Liversidge worked in the Department of Physiology in Cambridge University and of Chemistry in the University of Sydney, and was intimately concerned with the development of science as a whole; and the subject of electrical conduction in organic materials is related to chemistry and also to certain important aspects of physiology such as vision, as well as to solid state science to photosynthesis and to the mechanisms of some enzymic pro- cesses. The breadth of application of the subject of conduction in organic materials matches the extent of Liversidge’s own scientific interests. Professor Gutmann and colleagues (1966) have recently invented a new battery which uses organic solids, and yields 1-5 V, and is of potential use for space craft, being very light. *Acknowledgement is gratefully made for financial support by a grant, Number AF-AFOSR-863-65, from the Directorate of Chemical Sciences, U.S.A.F. Office of Scientific Research, for work described herein. A No metal is necessary, Also, The General Electric Co. in U.S.A. have made a non-metallic wire. These results indicate that some extra- ordinary practical developments may arise from the studies we are discussing, but they are not the subject of this talk. A recent publication discusses all aspects of the subject [Gutmann and Lyons (1967) |]. The Electrical Conductance of Metals and Inorganic Semiconductors When there is but one type of charge carrier, an electron or a positive hole, the conductivity o at a given temperature T and pressure p is given by the product of n, the number of carriers per cubic centimetre, and the mobility uw of the carriers : ora Uae er ee Oe (1) li @ 1s measured in cm volt sec4 then co gives the number of electrons flowing per second in a field of 1 volt cm~!. The significant but relatively minor differences between the Hall mobility and the drift mobility need not concern us in this discussion. Table 1 summarizes some of the basic data on the electrical properties of metals and in- organic semi-conductors. For metals, trom Table 1, it is seen that (i) n approximately equals the number of atoms cm ; (ii) o drops as T increases ; (i) w drops as T increases; and (iv) at room temperature, vu is often 10 to 100 cm? volt-! sec}. For the inorganic semiconductor, CuO (i) n is much lower than the number of atoms cm-?; (11) o and n both increase as T rises ; (i) as in metals, ux10 to 100 cm? volt-! Sec.+; and (iv) as in metals, uw drops as T increases. 2 L. E. LYONS TABLE 1 Data on Electrical Conductivity of Some Metals and Inorganic Semiconductors (o, conductivity ; wu, mobility ; n, concentration of carriers) Number of ap fo) Ue n & (1S) (ohms em?) (Cmaavin® “SeCrs) (coi) toms (cm-) Ag 290 6-2x 10° (—) 50 1 lore 5°9 x 102? Ag 15 Paix 10? (—)11,000 6-3 x 1072 Cu 290 5°8x 108 (—)28 13-0 x 102 8-55 x 102? Na 293 5:8x 106 (—) 60 2:5 x 1074 2:55 X 1022 Zn 293 eax 10 (+) 6 19-0 x 10? 6-6 x 1022 Ni 293 1-4~x 106 (—)90 1-05 1072 9-1 x 10?2 graphite (in plane) 10° (-E) 20,000 3 x 1018 1-13 x 1022 graphite (plane) i =) do Cu,O 163 220 >10=8 (—) 200 6-3 x 10° 2:5 x 102 Cu. ate 9-9x10-? (—) 20 5°6x 1011 Ge (high purity) 200 2°4 (—)4,000 3°5 xX 10"4 4-4 x10”? Ge (0-005A1) 100 140 (-+)6,000 Lb x POL 4-4 x10”? Ge (Sn) 100 83 (—)7,000 TOCA? 4-4 x10”? Source: Ehrenberg (1958). For germanium semiconductors (i) w is much higher than pw in Cu,O is in metals ; (i) n (and thus oc) can be determined by the concentration of an additive such as Al. Conductivity of Organic Solids (In this lecture the work of many workers is referred to; the contribution of our research group has been to propose and test the general theoretical framework for organic conduction.) The general result is typical of the behaviour of semiconductors G—6,1exp (-HjZk hai (2) E is the thermal energy necessary to form carriers. When the carriers are generated thermally within the crystal and when wp is independent of temperature Go—Nu (3) where N is the concentration of centres capable of yielding carriers. Measurements of co, and of uw thus enable N to be deduced. Mobility in organic crystals The pulse method of Le Blanc (1960) and Kepler (1960) yields values of uw in anthracene and naphthalene which are all of the order of 1 cm? volts sec. Positive holes and ‘electrons differ slightly in mobility ; in either cases pw is anisotropic, as is shown in Table 2. The mobility can be explained by band theory. Essentially a band of energy levels is formed for each molecular orbital, because of the overlap of the molecular orbitals in the crystal lattice. Fron the widths of the bands and from a theory of scattering the mobility can be calculated. On reasonable assumptions the results of theory agree with experiment. TABEBR2 Experimentally Measured Values of Mobility in Anthracene and Naphthalene ut - Anthracene Crystal; | (001) 0-4 0:3 0-98-+0-04 0:-54+0:-03 0-43 -+0-05 Crystal; || (001) 1-3 2-0 Cast slab 0-48 Crystal; ? direction> 2-3 Crystal 5 x 10-3 Crystaly ai 1 -O ie Crystal, Mp 2-0 1-0 Crystal, 4u¢¢ 0-8 0-4 wtf = 2-13 Crystal; || (001) 0-8 0-4 Naphthalene Crystal 0-9 0-7 Crystal, 4u,, 1-4 0-7 Crystal, 4u.¢ 0-4 0-4 “1. represents the component of the mobility tensor t24;, when 1=j=a, where a is a crystal direction ; a, b, and ¢ are mutually perpendicular. Source: Gutmann and Lyons (1967). ORGANIC METALS ? 3 The “ overlap ” or “‘ band ”’ theory of mobility is supported by the observed decrease of w with a rise in T, and by the observed increase of u with a rise in p (Figs. 1 and 2), after Kepler (1962). 3.6 3:2 20° to a axis 7 2.4 8 Parallel to i, 2.0 ab plane Te) > w_ 1.6 E E 20° to b axis ee 0.8 0.4 Perpendicular to ab plane 0 -—100 —80 -60 -40 —-20 0 20 40 Temperature, °C Fic. 1 Temperature dependence of electron mobility ; Kepler (1962). after All values of 4 might be expected to be of the same order of magnitude in a given class of crystal, e.g. in similarly structured molecular crystals of aromatic hydrocarbons. Values of o and of E are determined empirically from plots of log co vs 1/T. If uwx1 then oy, indicates the number of sources of carriers. Intrinsic conductivity would require o, to be ca. 1074 cm-. Extrinsic con- ductivity would be undetectable if og< ca. 1¢° cm-3, unless E were very small. Figure 3 summarizes the results of many workers on more than 160 substances. Nearly all lie within the expected limits for o,. The conductivity itself ranges over more than 20 orders of magnitude. In Figure 3, the lower on the diagram does a number (denoting a compound) occur, the greater is log o; and the more to the left does a number occur, the less 18 Gp. Most observations of conductivity are therefore consistent with extrinsic rather than intrinsic mechanisms. The common occurrence of extrinsic mechanisms is con- sistent also with the known difficulty of obtaining hyper-pure organic compounds. None is yet available commercially in a grade com- parable with that of the best germanium. From Figure 3 it is clear that less than one part in 10! of an active impurity in many cases can affect the observed conductivity. A new technology of purification and operation is therefore called for. Many experiments should be done in the absence both of light and of oxygen. The Energy Gap, E In equation (2), E ranges from 0 to more than 3eV. An explanation of E was given by Lyons (1957). For intrinsic conductivity thermal generation of carriers requires an energy given by equation (4). A | Ge eee ens (4) where I, and Ag, are the energies of subtracting and of adding an electron to the crystal. Values of I, can be obtained by photo- emission experiments. I, can also be related to the molecular ionization energy Ic by the polarization energy P, through equation (5) ; ie Pao ats 9k ace (5) We have established that I, is less than Ie, usually by about 2 eV. Values of Ic—I, (=P) are shown in Table 3. 25 20° to a axis , 2.0 Parallel to _ ab plane t 2 1.5 ("e) Fr = 20° to 6 axis > Xe o-1'0 =] 0.5 Perpendicular to ab plane 0 1000 2000 Pressure, atm Bic, 2 Pressure dependence of electron mobility; after Kepler (1962). 3000 iE LYONS 10849% = his CU ee 1S ST. gee (64 B Cy bl ss 33 e 3 47 Cag dh —» $8) 5 34 5 20 @ IS ry aes / 4b / es 57 q GO $3 a 4/ /o8 75 39 Eire Jo $2: 3/ aes b4 wL Gus), fe ee @ “s 21ND SE 5/7 78 7Y- 12@ 3°/S/ Jk O89 a — . / O 02 0. 0.6 0-9 ; /-o /2 /-44 Wf E(eV) in o = o, exp (-E/kT) FIGs 3 Values of o, for observed E and o in reported experiments on dark conductance. (o, is in amps X 10!?) ORGANIC METALS? D Calculation of P was made from the formula Peo 3-8, Sly. «7 — or 27 7 p= wetn Br Pr FI aN Ne Nd Na] N-1 ; 2 oe 24e a/Ty. More complicated expressions involving higher terms and anisotropic molecular polarizabilities are given by Mackie (1964) and by Batley (1966) who used also a computer programme to increase the accuracy. The theory assumes (i) crvstal TABLE 3 Values (eV) of Ig-T, Equated to the Polarization Energy P of a Single Charge Anthracene rs Perylene 1-9 Chrysene eel Phenanthrene 1-4 Coronene 2-4 Phthalocyanine, 9, 10-Dibromo- 7n l anthracene 1-9 to Pinacyanol 29 2-4 Pyrene bea n-Hexane a, Ouinoline blue 2-0 Indigo blue I 8 Rhodamine 6G 1-6 Merocyanine 2-2 Water 5G 20 Naphthacene L-6 7:0 Naphthalene a3} Source: Gutmann and Lyons (1967). structures from x-ray work and (11) molecular polarizabilities, available in many instances from the work of Professor Le Févre and collea- gues. [Le Févre and Sundaram (1963) ]. When account is taken both of ion induced- dipole and dipole-dipole interaction the theory calculates P to lie within a few tenths of an electron volt of the observed difference between Ig and Ic. Since there are errors in experiments and necessary approximations in the theory, the agreement is satisfactory. In this way the theory of photoelectric emission thresholds in organic solids has been established reasonably well. Calculated values are shown in Table 4. The electron affinities Ae of certain dye crystals have been reported as 3:3-+0-3 eV (Nelson, 1956). There is no other direct measurement. However, Ac can be related to the corresponding molecular property Ac by equation (6). ING ANGE bd a.5h yee ss aes 0 (6) where P refers to the energy of the polarization produced by the negative charge, a quantity which will be very close to that produced by a positive charge. ~ 1—5, anthracene ; 11, benzimidazole ; 19, flavanthrone ; Key to Fig. 3: 10, benzene ; 18, cyananthrone ; 22, imidazole ; 23, indanthrazine ; isoviolanthrene ; 28-29, isoviolanthrone ; m-naphthodianthrene ; 37, 6—7, anthanthrene ; 12, o-chloranil ; 20, hexamethylbenzene ; 24, indanthrone ; 31, naphthacene ; m-naphthodianthrone ;_ 38, 8, anthanthrone ; 9, benzanthrone ; 13, chlorpromazine ; 14-17, coronene ; 21, hydroviolanthrene ; 25, indanthrone black; 26-27, 30, 32-35, naphthalene; 36, octohydroviolanthrene ; 39, ovalene; 40, pentacene; 41-47, perylene; 48, phenazine; 49, phenothiazine; 50-51, phthalocyanine ; 52, pyranthrene; 53, pyranthrone; 54-55, pyrene; 56, quaterrylene ; 57, o-resorcin; 58-59, 6-resorcin; 60-63, violanthrene; 64, Banfield and Kenyon’s radical; 65, Coppinger’s radical; 66, DPPH; 67-68, violanthrone-B compound; 69, 1,9,4,10-anthradipyrimidine ; 74, fluorescein-Na; 75, indanthrazine ; indigo ; 79, nacrosol black ; 70, crystal violet ; 76, indanthrone ; 80, orthochrome T ; 71-72, cyananthrone; 73, flavanthrone ; 77, indanthrone black; 78, 81, 5,6-(N)-pyridino-1,9-benzanthrone ; 82, acenaphthene: TCNE; 83, anthracene: TCNE; 84, azulene: TCNE; 85, 6-carotene triiodide; 86, coronene: iodine; 87-89, 1,6-diaminopyrene: chloranil ; pyrene: chloranil; 95, 3,8-diaminopyrene : 97, dimethylaniline: bromanil ; iodanil; 100, hexamethylbenzene : isoviolanthrone: (AICI,)5.,; 103, (ICl),-99; 105, isoviolanthrone : lithium: anthracene; 108, naphthalene : Tl@;-perylene: SbCl,; 111, perylene: fluoranil; 114-117, perylene: iodine ; TCNE ; 120, phenanthrene: TCNE ; lenediamine: chloranil ; 125-126, potassium: isoviolanthrene ; bromine; 129, pyranthrene: iodine ; 132, pyrene: TCNE; 133, pyrene: anthracene; 135, Na: 1,5-diaminonaphthalene : 92-93, 3,8-diaminopyrene : iodanil ; 98, dimethylaniline : TCNE ; isoviolanthrone : (ICl) 3.75 5 TCNE; Bins: 118, perylene : 121, phenylenediamine: chloranil ; 123, phthalocyanine : 127, potassium : 130, pyrene : TCNO; 3,4-benzoquinoline ; chloranil; 90-91, bromanil; 94, 3,8-diamino- 96, 3,10-diaminopyrene: chloranil ; chloranil; 99, dimethylaniline : isoviolanthrene: (AICI;)3..; 102, (ICl),.4,; 104, isoviolanthrone : isoviolanthrone: —(l1Cl) 3.55. LOT, 109, pentamethylbenzene: TCNE; 112, perylene: chloranil; 113, perylene: metal halides; 119, perylene: 122, p-pheny- 124, potassium: anthracene ; TCNQ; 128, pyranthrene : chloranil; 131, pyrene: iodine ; 1336, quinolinitum: (TCNQ),.; 134, Na: 136, Na: isoviolanthrene; 137, Na: 101, 106, chloranil ; isoviolanthrene ; 138, tetramethyl-p-phenylenediamine : bromanil; 139-140, tetramethyl- p-phenylenediamine: chloranil ; triethylammonium (TCNQ), ; moreerato (Vr T,)s Te 38°F) Ve 1-9, 1: 142, violanthrene : 141, tetramethyl-p-phenylenediamine: iodanil; 1410, Br,; 148-148, violanthrene (V): I,, O-118,) i: 10-01; 1: 00036, 1: 5x 10-4; 149-150, V: I,; 151, V: TCNE; 152, dipyrromethene-1l, cobalt ; 153, dipyrromethene-2, cobalt ; 154, dipyrromethene-1, copper ; 155, dipyrromethene-2, copper ; 156, dipyrro- methene-1, hydrobromide ; 157, dipyrromethene-2, nickel; 158, ferrocene; 159, phthalo- 160, phthalocyanine, Mg ; Source of data : cyanine, Cu; 161, phthalocyanine, Zn. Gutmann and Jyvons (1967) 6 CE LYONS Thus if we can get Ac we can determine A, and vice versa. In the course of our work we have used two methods of arriving at values of Ac. The first general. method derived Ac TABLE 4 ~ Calculated Values of Polarization Energy (eV) Py Pp Ion-dipole Dipole-dipole Pi+Pp naphthalene — JO) +0°-41 =—]- 60 anthracene —2 +35 -0-54 —1-81 naphthacene 281 0-66 a2 pentacene —2-08* +0-64 —]-44* coronene —2'- 21% 4+-0+37 —] -84* chrysene —2+30* +0-82 —]-48* anthracene: TNB -2-53* +0:37 —2-16* *JTon-dipole term not extrapolated to infinite radius. from polarographic reduction potentials in solution [Lyons (1950)], while the second derived Ac from charge-transfer spectra in solution [Briegleb (1961), Batley and Lyons (1962)]. In addition theoretical and other methods of various kinds have been used le.g. Hoyland and Goodman (1962) ]. All methods suffer from the difficulty of how to place the values on an absolute scale. However, when values relative to benzene are considered, the various methods yield values in reasonably good agreement with each other as Table 5 shows. [For absolute values, the discrepancies amongst the results of various methods have very recently been removed by Batley (1966). | Thus, whilst relative molecular electron affinities are available at least for the aromatic hydrocarbons the lack of an accurate absolute value is still a problem in understanding the electrical properties of solids. This appears when equation (4) is rewritten using equations (5) and (6), as E=Ig—Ac—2P The validity of this approach is seen in the case of dyes which in Figure 3 were found to obey the equation for intrinsic conductivity. Also Ac (=Ac+P)=8:3 eV typically [Nelson (1956)] and Ic (=Ic—P)=5-1 eV typically. We thus predict E as 5-:1—3-3=1:8 eV (eq. 4), a value which compares with the _ typical experimental value of 1:8 eV (Figure 3). The general mechanism is thus supported. Inciden- tally also, the molecular electron affinity of the dye molecule can be deduced to be 1 eV, because AG Nc le lc). ae es (8) There is a further set of experiments to which the same basic theoretical approach can be applied: The effect of high pressure upon the electrical conductivity of organic substances — was observed but was unexplained until recently. It had been shown (Harada e# al. 1964) that the greatly increased conductivity which is observed at high pressure is only 10%% explicable in terms of an increased mobility. The increase in o must therefore be caused by an increase in the number of carriers 1.e. by a decreased value of E. We now use equation (7) to discuss the decrease in E, The polarization energy, calculated as described above, is a function of the lattice parameters and must change when the crystal is compressed. Batley and Lyons (1966) have shown that the increase in carrier concentration can be explained by the change in the size of the unit cell with pressure (see Figure 4). Using the equation kTIn ee ! | =aP aun Oo, p ey where the subscript p denotes values at high TABLE 5 :lectron Affinity Energies AAg of Organic Molecules Relative to that of Benzene Substance AAg Mean Anthracene 1:8 2-0 1:8 2-0 2-1 2-0 2-1 Coronene 1-8 1-85 1:9 1-8 Diphenyl bel 0:8 1:3 Naphthacene 2-4 2:3 2-4 2-2 Naphthalene 1-1 Ir2 1-0 1-3 1-2 1:3 1-4 Perylene 2-1 2-2 2°3 2a, Phenanthrene 1-4 1-4 1-6 1-6 1-1 Pyrene 1-6 1-9 1-7 2°3 2-0 Source : Gutmann and I.yons (1967). ORGANIC METALS? 7 pressure and AP=P,—P the theory in fact rather over explains the observations, which however are at present subject to an unknown error. Because Eyp=E—2AP (10) an interesting situation is predicted to arise when AP is sufficient to make Ep equal to zero. In this case equations (2) and (3) yield AN ets. cin! Pinta Gif aS ene (11) so that ow10? to 104 chm cm}, a value which approaches that of metals. This behaviour has been observed, e.g. in copper and metal-free phthalocyanine. On returning to atmospheric pressure the metallic behaviour disappears, again as the theory predicts. 7 8 © © ee ee ew ee TABLE 6 Molecular Ionization Energy, Ig, and Molecular Structure Ic Substituted Ie (eV) benzene (eV) benzene 9-245 —H 9-245 naphthalene 8-12 —CH, 8:81 anthracene 7°38 —C,H,; 8:76 naphthacene 6-88 —CHO 9°45 —COCH, 9-65 —CN 9-705 —NH, 7:56 pyridine 9-32 —NH.NH, 7:64 p-benzoquinone 9:67 —OH 8-52 phenothiazine 7-14 —SH 8°33 1,5-naphthalene diamine 7:2 —o 8-27 bis-cyclopentadienyl Co 6:2 —NH,\.. 7.9 _NH, eee 2 —N.Ne.| ¢.¢ —N.Ne, f ° Source: Gutmann and Lyons (1967). : Conductivities at p=1 bar Using equation (7), and requiring E to be low, it 1s clear that in order to increase o we must (i) decrease Ic, (ii) increase Ac, and/or (ili) increase P. Since P varies only over a limited range we consider only Ic and Ag in this section. The dependence of Ic upon molecular structure is shown in Table 6 which presents only a sample of values. For example, Ic is lowered (i) by an increase in conjugation and (ii) by the introduction of —N.Me,, -NH,, —OH, and -CH, groups. The dependence of Ag upon molecular structure is such that Ac increases (i) with an increase in conjugation and (ii) with the intro- duction, e.g., of -CN, —NO,, or —Cl substituents. For crystals containing only one type of molecule conduction is favoured if there is extensive conjugation. Graphite is a limiting case here: its properties are wellknown (cf. 1.0 AE (ev) fo) 100 200 fv (k bar.) ———_—_» Fic. 4 Change AE of the energy gap with pressure, p, for the semiconductivity of pentacene. Batley (1966). Table 1). Pohl and colleagues [Pohl (1962)], as well as other workers, have made scores of polymers in which conjugation extends throughout the polymer molecule. As expected Ic is low, Ac is high and so oa is high: c=10-3 for poly dibenzpyrene (E=0-2eV); and o=10-4 for polypyrene (E=0-2eV). The lack of a perfect single crystal lowers yu to 10-2 or 10-* cm? volt-! sec! and so limits o. 2-7 2:8 29 3-0 3+ 3-2 3-3 (a4°c) = (72°C) (50°c) o% Fic. 5 Conductivity vs inverse temperature plots tor anthracene crystal containing additives. Johnston and Lyons (1966). 8 Ey LYONS Polyacenequinone radicals polymers can show o=10-5 ohm, with uw probably about 10-’, and E>0:26eV. TABLE 7 A Eimp fest) Eimp +Ag o-chloranil 0-65 hei) 2°55 pentacene 0-95 1-2 749 | anthraquinone 1-10 1-05 7 anthanthrene Te ? tetracene P23 0-95 2°2 perylene 1-6 0-9 2:5 Source: Johnston and Lyons (1966). Doping The addition to a crystal of a small amount of an additive which has a lower Ic or a higher Ac than the _ corresponding value for the host molecule should lower E and raise the conductivity. Figure 5 shows that this is in fact so. Table 7 indicates that it is Ac rather than Ic which is important here. The E values decrease as Ac is increased. Once again support is obtained for the use- fulness of equation (7). Doping with an alkali metal (Icx5eV) is expected to give similarly increased conductivi- ties. | Amongst organic materials bis-cyclo- pentadienyl cobalt (Ic=6-2eV) should be worth trying and this we plan to do. The limiting case of “doping ’”’ is found in the donor: acceptor complexes which can be, e.g., 1:1 0r1:2. Table 8 lists the resistivities TABLE 8 Electrical Resistivities of Some Donor Acceptor Complece Mole Resistivity Donor Acceptor Ratio GretGn acenaphthene TCNE 5x: 10% benzidine 1 Ll TOs caesium tetrachloss 8 pyrene 3,8-diaminopyrene domanil 10° perylene domanil 8 perylene iodine 23 3 Source: Gutmann and Lyons (1967). of some donor acceptor complexes. Of those listed the lowest resistivity is that of perylene- iodine. For the 1:3 complex p=8 ohm cm, while for the 2:3 complex o=3 ohm cm, with 2<0-01. Some 1:1 donor complexes, such as Kt chloranil-, are completely ionic and there is a resemblance to K+tCl- type solids. Using Ic and Ag values Mackie (1964) predicted the existence of a number of such substances. However, the resistivity is high—potassium — chloride is an insulator. For good conductivity it is necessary not only to have an abundance of ions such as chloranil- but also to have neutral molecules as neighbours to the ions. The electron can then move from one site to its neighbour with practically no change in energy. Steric arrange- ments should be suitable for the electron transfer. A favourable arrangement has been found amongst 1:2 complexes. Thus the conductivity of K+ TCNQ- is ca. 10-* ohm-} cm-!, while that of K+ (TCNQ)-, is ca. 107. Similar and even higher conductivities can be obtained with completely organic materials, e.g. for NEtt, (TONO)}S c= 7) =md tor QO+ (TCNQ)-,, o%100; where Q+ denotes the quinolinium ion; Et, the C, H; group; TCNO, tetracyanoquinodiemethane. TABLE 9 Number of Crystal Molecules cm anthracene 4°3x 1071 naphthacene 3-5 x 1074 naphthalene 5:4x 1074 perylene 3a x 1O2t In O+ (TCNQ)-, the mobility im pellets 1s rather small (10-7). No good independent measurement of the mobility on single crystals exists. Such measurements would allow a study of the possibility that » has been limited by impurities and other crystal defects. If this is so and » could be increased by better purifi- cation of the crystals then co would be raised to perhaps 10* ohm? cm. Ultimate Limits on High Conductivity of Organics Table 9 gives the number of molecules in a centimetre cube of some aromatic hydro- carbons. These values are all slightly more than one order of magnitude less than those found with metals. The simple fact that an organic molecule is bigger than a metal atom means that the number of sources for carriers must generally be less than in metals. _ None the less conductivities as great as those in metals are not inconceivable. What is lost in the number of carriers may possibly be offset in the mobility. Although mobilities in the anthracene type crystals so far measured are relatively low, there are already a few ORGANIC METALS? y experiments which point to higher mobilities in favourable directions in certain crystals. Conjugated polymers as single crystals and some hydrogen-bonded crystals are likely examples. It must be remembered that in graphite 120,000 cm? V-! sec-t. Conclusion The day may well arrive when organic materials other then graphite will be made with conductivities of 104 or greater. Speaking electrically, organic metals exist already at high pressures, and the theory outlined in this paper shows that at present they are not far from existing under ordinary pressures. References BaTLey, M., 1966. Ph.D. Thesis, University of Sydney. IBATLEY, M., anD Lyons, L. E., 1962. Nature, 196, 573. BATLEY, M., AND Lyons, L. E., Chem., 19, 345. BRIEGLEB, J., 1961. Elektronen-Donator-Acceptor- Komplexe. Springer, Berlin. 1966. Austral. J. EHRENBERG, W., 1958. Electric Conduction in Semi- conductors and Metals. Oxford, 22. GUTMANN, F., HERMANN, A., AND KEMBAUM, A., 1966. J. Electrochem. Soc., in press. GUTMANN, F., AND Lyons, L. E., 1967. Semiconductors. Wiley, New York. HARADA, Y., MARUYAMA, Y., SHEROTANI, I., AND INokucHI, H., 1964. Bull Chem Soc. Japan., Of, dade: HOYLAND, J. R., AND GooDMAN, L., 1962. Phys., 36, 21. JOHNSTON, G., AND Lyons, L. E., 1966. Unpublished. KEPLER, R. G., 1960. Phys. Rev., 119, 1226. KEPLER, R. G., 1962. In: Organic Semiconductors. Eds. J. J. Brophy and J. W. Buttrey. Macmillan, New York, 1. EEWDBLANG.“Oo-He 1443. Le FEvrReE, R. J. W., AND SUNDARAM, K. N., 1963. J. Chem. Soc., 4442. LITTLE, W. A., 1964. Phys. Rev., 134A, A1416. Lyons, L. E., 1950. Nature, 164, 193. LVONS, 1K, 1957s." Austral” Jc, Sct; 10; 365. J Chem. Soc. (London), 5001. MacklizE, J. C., 1964. Ph.D. Thesis, University of Sydney. NELSON, R. C., 1016. POHL, H., 1962. Modern Aspects of the Vitreous State, Ed. J. D. Mackenzie, Chapter 2. Organic \.aChem, jr L960— jeChem? Phys: 530; 1956. J. Optical Soc. Amer., 46, Journal and Proccedings, Royal Society of New South Wales. Vol. 101, pp. 11-15, 1967 Abiogenesis Leading to Biopoesis KRISHNA BAHADUR and INDRA SAXENA Chemistry Department, University of Allahabad, Allahabad Introduction As protein is the basic building material of all the living system of our earth, the abiogenesis of protein is one of the most important aspects of biopoesis. However protein formation starts with the search for the process under which the amino acids are formed abiogenically. Several processes have been discovered which form amino acids under abiogenic conditions. The formation of amino acids was observed for the first time by Loeb in 1913! who reported the formation of amino acids as glycine and alanine by passing silent electric discharge in a mixture of formaldehyde, ammonia and water. Amino acids have been synthesised by passing electric discharge in a mixture of gases by Muller?. The photochemical formation of natural amino acids was. observed’ by Bahadur®: 45 in sterilised aqueous mixtures containing organic substances and inorganic catalysts. Hasselstrom exposed aqueous solu- tion of ammonium acetate and observed the formation glycine and aspartic acid®. The synthesis of amino acids and other compounds of biological interest have been done using isocyanates’, energy from ultra violet rays® to x-rays radiations? and other sources of energies have also been used for this abiogenesis. The next important step in abiogenesis was the formation of peptide linkage. hep. synthesised peptides by heating the mixtures of amino acids to 180°C for a few hours. -Akabori#! synthesised peptide by exposing aqueous mixture of amino acids to ultra-violet light. Terenin!? suggested the possibility of effecting the reactions needing quanta of large amount of energy by radiations of shorter quanta of energy if the substrate molecules are absorbed on solid substances. Bernal!® reported the formation of peptides by the radiations available on the earth in the mud. Bahadur and Ranganayaki in 1958 observed the formation of peptides in aqueous mixture of amino acids containing colloids of iron and molybdenum oxides as catalysts on irradiation with sunlight or artificial light from an electric bulb™. Perti and Pathak! observed the forma- tion of peptides in aqueous mixtures using visible light and ultra-violet light in presence of inorganic catalysts. Briggs confirmed the observation of photochemical formation of peptides!®. The synthesis of peptides in aqueous mixtures using hydrogen cyanide as the dehy- drating agent has been observed by Lowe!’. The photochemical formation of peptides in aqueous mixtures is interesting and becomes important because, put together with the observation of photochemical formation of amino acids, it is quite probable that amino acids were first formed in the oceans of the primitive earth and then these were subsequently utilized for the formation of peptides in almost the same environment or on prolonged exposure. These photochemically formed peptides have been examined for enzymic activity. The results show enzymic function as phosphatase activity. Bahadur!® suggested that the formation of amino acids and peptides took place in aqueous environment in the prebiological era and solar radiation and visible light played an important role in the syntheses. Then on further molecular evolution proteins were formed. This theory regarding the origin of lite on the earth has been developed recently! 2°. In the present communication an attempt has been made to study the formation of amino acids, peptides, organic acids, sugars and enzyme activity in sterilised aqueous mixture containing glycine, methionine, aspartic acid cystein and anthracene as catalysts by exposing these mixtures to artificial light. Experimental A set of two mixtures in sigcol flat bottom flask of 250 ml. capacity was prepared in glass distilled water. The contents of the mixtures were as follows : Glycine ..0°05 gm. Aspartic acid. .0-05 gm. Methionine ..0-05 gm. Cystein HCl ..0-05 gm. and Anthracene 0-02 gm. as catalyst in 100 ml. of water. ; TABLE Mixture of Uncovered Flask (Light) Rf Values in Phenol] Butanol: S.No. Identifi- Remark Water Acetic cation acid : Water 80; 20° 120 30: 50 Microstructures : Hydrolysed 0-16 Q-14 Cystein Yellow 0-15 0-28 Aspartic Pinkish acid purple 0-32 0-26 Serine Purple 0-52 0-27 Arginine Purple 0-58 0-34 Alanine Purple Unhydrolysed 0-51 0-27 Arginine Purple 0-61 0-81 Peptide: Purple 0-31 Osa Peptide; Purple faint 0-28 0-69 Peptide’ ~ Purple faint Environmental Medium : Unhydrolysed 0-16 0-14 Cystein Yellow 0-75 0-58 Peptide Purple 0-52 0-59 Peptide Purple Hydrolysed 0-16 0-14 Cystein Yellow O= 15 0-28 Aspartic Purple acid (pink- ish) 0-30 0-35 Glutamic Purple acid 0-52 0-27 Arginine Purple 0-41 0-3 Glycine Purple 0-81 0-70 Methio- Purple nine 0-61 0-52 ? Purple KRISHNA BAHADUR AND INDRA SAXENA 35° in the incubator for three to four days. The mixtures did not show any bacterial growth during the exposure. These mixtures were analysed for their microstructures and environ- mental medium after separating them by the help of ultra centrifuge, each was analysed for hydrolysed and non-hydrolysed nitrogenous constituents by two way paper chromatographic technique, employing phenol-water (80: 20) and butanol—acetic acid-water (120: 30: 50) as two running solvents. Hydrolysis was done with 10N—HCI in sealed, hard neutral glass ampules, kept in boiling water for 24 hours. The hydrolysed samples were neutralised simultaneously in vacuum desiccator in presence of fused NaOH. Whatmann No. 1 chromatographic papers were used. Spots of amino acids and peptides were developed by spraying 0-2°% ninhydrin solution in acetone over the dried chromatograms, spots of organic acids by 1°% bromophenol blue. Spots of sugars were developed by ammoniacal silver nitrate. The Rf values change due to many factors such as change of solvent and also due to the degree of hydration of the same_ solvent. TABLE 2 Mixture of Uncovered Flask (Dark) dried and The flasks containing above mixtures were cotton plugged with surgical cotton, and sterilised at 15 lbs. pressure for 30 minutes in an autoclave. The mouth of the flasks was sealed with cello-adhesive tape after wrapping with polythene paper. One of the two fllasks was covered with thick black cloth and the other remained as such. The covered and uncovered flask was kept for exposure to artificial light under 1000 watt electric bulb. The temperature during the period of exposure varied from 18° to 30°C. After 560 hours of irradiation to artificial light, the mixtures of covered and uncovered flask were examined under the oil immersion microscope (D. R. P. Leitz wetzlar microscope) using aseptic condi- tions and no bacterial growth was observed. The sterility of the exposed mixtures was also checked by the culture-count method. Few drops of the exposed mixtures to be tested were introduced over the agar nutrient in the petri- dishes under aseptic conditions and kept at Rf Values in Identifi- cation S.No: a Remark Phenol: Butanol : With Water Acetic OF29% acid : ninhydrin Water in 80:20 120:30:50 acetone Microstructures : Unhydrolysed 0-16 0-14 Cystein Yellow 0-18 0-21 Peptide, Purple 0-43 0-35 Peptide Purple Hydrolysed 0°15 0-28 Aspartic Pinkish acid purple 0-81 0-70 Methio- Purple nine 0-16 0-14 Cystein Yellow 0-4] 0-31 Glycine Purple 0-51 0:27 Arginine Purple 0:56 0°73 ? Purple Environmental Medium : Unhydrolysed 0-16 0-14 Cystein Yellow 0-15 0-28 Aspartic Pinkish acid purple 0-31 0:39 Aleptide Purple Hydrolysed 0-16 0-14 Cystein Yellow 0-15 0-28 Aspartic Pinkish acid purple 0-8] 0:69 Methio- Purple nine 0:41 0-31 Alycine Purple 0-51 0-27 Arginine Purple ABIOGENESIS LEADING TO BIOPOESIS 13 Therefore the Rf values of known, amino acids, organic acids and sugars were occasionally determined and the Rf values of unknown amino acids, acids and sugars were compared with those of known ones. The two running solvents were used in all the experiments for identification. This was accompanied by two dimensional chromatography. TABLE 3 Mixture of Uncovered Flask (Light) Rf Values in Identifi- cation SNe. ooo Se eli ats Phenol: bButanol : With Water Acetic OrZ of, acid : Bromo- He© phenol 80:20 120:30:50 Blue Microstructures : Unhydrolysed Nospot No spot Hydrolysed 0-51 0-42 2 Yellow- ish 0:32 es | Benzoic Yellow- acid ish Environmental Medium : Unhydrolysed 0:32 0-21 Benzoic Yellow acid 0°51 0-42 ? Yellow ()- 24 0:21 ? Yellow Hydrolysed 0-78 0-62 Myristic Yellow acid 0-36 0-83 Oxalic Yellow acid 0-24 0-24 ? Yellow Estimation of phosphatase activity : The phosphatase activity was estimated colorimetrically employing the Klett Summerson photo-electric colorimeter for the measurement of intensity of colour produced using suitable filter. The analysis is based upon the measure- ment of the quantity of light absorbed by a coloured solution. The dilution of the solution was adjusted so as to hold Beer’s Law, ie. the scale reading was directly proportional to the concentration of phosphate ions in the mixture. To avoid the frequent change in potential of the current supply the voltage stabiliser was used. The results of the chromatographic analysis of each flask are recorded in tables 1 to 7. One more identical mixture, as described in the experimental portion of this paper, was prepared. It was sterilised, cooled, covered with four folds of thick black cloth and stored in a lead chamber the walls of which were made TABLE 4 Mixture of Covered Flask (Dark) Rf Values in Identifi- cation S.No. Be —_———— Remark Phenol: Butanol : With Water Acetic 0:2% acid:; Bromo- H,O phenol 80:20 120:30:50 Blue Mucrostructures : Unhydrolysed Nospot No spot — — Hydrolysed 0-32 0-21 Benzoic Yellow acid 0-38 0:35 sf Yellow Environmental Medium : Unhydrolysed 0-32 0-21 Benzoic Yellow acid 0-14 0:40 ? Yellow Hydrolysed 0-36 0-83 Oxalic Yellow acid 0-78 0-62 Myristic Yellow acid of 2-54 cm. thick sheets of solid lead. This mixture was analysed at the end of the experi- ment and was found to contain only the added amino acids. No other spot of amino acids, peptide, sugar or organic acid was detected in this mixture. There was no appearance of any microstructures in this mixture and the mixture had no phosphatase activity. Thus this control remained unchanged during the period of experiment. TABLE 5 Mixture of Uncovered Flask (Light) Rf Values in Identifi- cation S.No. - —Remark Phenol: Butanol: With 1st) Acetic Ammonia- acid : cal Silver ne® Nitrate Microstructures : Unhydrolysed 0-53 0-31 Mannose White 0-24 0-52 ? White 0-56 0-22 Sucrose White Hydrolysed 0-53 0-31 Mannose White 0-52 0:28 Glucose White 0-26 0:50 ? White Environmental Medium : Unhydrolysed 0°53 0-31 Mannose White 0:26 0-52 fe White Hydrolysed 0-53 0-31 Mannose White 0:52 0:28 Glucose White 0:36 0:56 ? White 14 KRISHNA BAHADUR AND INDRA SAXENA Discussion The chromatographic analysis of irradiated aqueous mixtures containing glycine, aspartic acid, methionine, and cystein and anthracene as catalyst incicated the presence of original amino acids added in the mixture together with a few peptide spots. This mixture on TABLE 6 Mixture of Covered Flask (Dark) Rf Values in Identifi- cation S.No. ———_________—— Nem aiic Phenol: Butanol: With H,O Acetic |Atmmonia- Acic.: cal Silver 11.0 Nitrate Microstructures : Unhydrolysed 0:53 0-31 Mannose White ; 0:56 0-22 Sucrose White Hydrolysed 0-53 0-31 Mannose White 0-52 0:28 Glucose White 0:36 0:56 ? White Environmental Medium : Unhydrolysed 0°53 0:31 Mannose White ; [ 0-32 Or 48°" 2 White Hydrolysed 0-53 0-31 Mannose White ; 0-36 0-56 ? White hydrolysis showed the presence of all the original amino acids and also gave newer spots which were identified as, arginine, alanine, and seriene. Similar mixture kept in dark showed the presence of all the originally added amino acids together with a few peptide spots. The mixture on hydrolysis gave the spots of the added amino acids and also of arginine, alanine and seriene as in exposed mixture. In general it has been observed that there were a few spots in unhydrolysed samples, but the same sample on hydrolysis indicated several spots which revealed the constituent amino acid of those peptides which did not appear over the chromatogram of the unhydrolysed sample. The complete identical mixtures kept in dark furnished peptide spots but these were lesser in number than those of the exposed mixture. It has been observed by Bahadur and co- worker?’ in their studies of the photochemical formation of amino acids and peptides that the control identical mixtures kept in dark also show some amino acids and peptide synthesis. They further observed that similar mixtures kept in lead chamber remained unchanged. The fact is that radiations which penetrated through the thick black cloth and reached the mixture kept in dark were also effective in the synthesis of some of these products. In the above lead chamber which had one inch thick wall of solid lead, all the radiations including cosmic radiations were cut off and no change in the mixture was effected. Microstructures were observed in the mixtures after exposure. Similar micro structures but lesser in number were also observed in the identical mixture kept in dark. It is interesting to note that the microstructures of the mixtures exposed to light and kept in dark did not show the presence of any organic acid. The micro structures on hydrolysis showed the presence of myristic acid, oxalic acid and benzoic acid. The environmental media of these mixtures also showed the presence of these organic acids after hydrolysis. A few spots of some organic acids were recorded but these could not be identified in both the cases. The micro structures formed in the exposed and unexposed mixtures showed the presence of sugars as mannose and sucrose. These on hydrolysis gave some more spots of sugars TABLE 7 Phosphatase Activity in the Mixture Examined by Kiett Summerson Photoelectric Colorimeter Boiled Unboiled S.No: = 5 = = oO rnin. 20 min. 40 min. 80 min. o rhin. 20 min. 40 min. 80 min. Spontaneous 12 13 15 15 15 14 13 13 (Control) Uncovered 14 16 20 20 9 12 16 16 (Light) Covered 30 32 35 35 16 15 15 [5 (Dark) ABIOGENESIS LEADING TO BIOPOESIS 1S along with those present in unhydrolysed ones. A similar observation was made in the environ- mental medium of the exposed and unexposed mixtures. More of the sugar was formed in the environmental medium in comparison with that of micro structures synthesised in the exposed mixture. However a larger quantity of sugar was present in the microstructures than in the environmental medium of unexposed mixtures. The exposed and unexposed mixtures were examined for enzymic activity and more of the phosphatase activity was observed in_ the unexposed mixtures. This phosphatase activity was found to be destroyed on boiling the exposed and unexposed mixtures at 100°C for five minutes. The greater enzymic activity in the mixtures kept in dark may be due to the stability of the peptides synthesised in these mixtures because of the mild source of energy affecting these mixtures and there is less of the thermo- dynamical possibility of the decomposition of these peptides in the mixture than in the similar exposed mixtures. Summary The mixtures containing amino acids as, glycine methionine, aspartic acid and cystein hydrochloride and anthracene as catalyst, on exposure to artificial light indicated the presence of some new amino acids other than originally added, organic acids, sugars and enzymic activity. The similar mixture kept in dark also indicated the presence of new amino acids, organic acids and sugars, but lesser in number as compared with exposed (light) mixtures. However enzymic activity was more pronounced in dark (unexposed) mixture than in light one, and in a lead chamber only the added amino acids were present. References 1Lors, W., 1913. Ber. dtsch. Chem. 2 MILLER, S., 1953. Science, 117, 528. 3 BAHADUR, K., 1954. Nature, 173, 1141. Ges., 46, 691). 4 BAHADUR, K., and RANGANAYAKI, S., 1954. Proc. Natl. Acad. Sci., India, 23A, 21-23. > BAHADUR, K., and RANGANAYAKT, S., 1955. Compt. vend., 240, 246. 6 HASSELSTROM, T., HENRY, M. C., and Murr, B,, 1957. Science, 125, 350. 7 Oro, J., 1963. Ann. N.Y. Acad. Sci., 108, 464, 1961, Arch. Biochem. Biophys., 94, 217-227, 1962, ibid. 96, 293-313. 8 GROTH, W., and WEYSSENTROFF, H. V., 1957. Nature wissenschaften, 510. 9 Dose, K., and BajrEssxky, N., Biophys. Acta, 25, 225. 10 Fox, S. W., Harapa, K., and VEGossky, A., Experimentia, 15, 81. 4 AKABORI, S., 1959. Proc., First Intern Symposium, “The origin of life on the Earth’’, Moscow 1957, Pergamon Press ed., 169-195. 12 TERENIN, A. N., 1955. Microchem. Acta, H 2-3, 467, 1955. Symposium. Problem of Kinetics and catalysis, XIII; Ed. Acad: Sci, U.S.S.R., 27-30. 13 BERNAL, J. D., 1961. Oceanography Am. Association of Advancement of Sci., 95-118. 14 BAHADUR, K., and RANGANAYAKI, S., 1958. Izyestiya A Kademunauk, U.S.S.R., 11, 1361-1369, 1958, Proc. Natl. Acad. Sci. India, 274A, 6, 292-295, Bahadur, K., and Srivastava, R. B., 1960. Indian J. Appl. Chem., 23 (3), 131-134, Bahadur, K., and Pande, R. S., 1965. J. Indiaw Chem. Soc., 42 (2), 75-85. 15 PerTI, O. N., BaAHapur, K., and PAtHak, H. D., 1957. Btochem. et. 1959. 1961. Proc. Natl. Acad. Sci. India, 30A, 206-220, 1961. Indian J]. Appl. Chem., 25, 90-96, 1962. Biochem. J]. U.S.S.R., Bol. 4, T. 27, 708-714. 16 Briacs, M. H., 1965. Space Flight, 7, (4), 129-131. 17 LowE, C. V., REEs, M. W., and Marxuam, R., 1963. Nature, 199-222. 18 BAHADUR, K., 1957. Report, International Sym- posium on “ Origin of life Moscow, 86—96. 19 BAHADUR, K., and Saxena, I., 1963. Vijanana Parishad Anusandhan Patrika, 6, 161-168. 20 AGRAWAL, K. M. L., 1963. D.Phil. Thesis, ‘‘ Photo- chemical and Biochemical Fixation of Nitrogen "’ University of Allahabad. on the Earth’’. Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 17-21, 1967 Aquifer Water Resistivity—Salinity Relations D. W. EMERSON Department of Geology and Geophysics, University of Sydney, Sydney ABSTRACT.—Aquifer water resistivity (Rw)-lonic concentration relations are briefly discussed. The application of some Ry estirnation methods to forty-five N.S.W. water samples demonstrates that, in the absence of ionic information, the solutions of the forward and inverse estimation problems could contain large errors. concentration in N.S.W. aquifers. Introduction In recent years it has been recognised in hydrogeological investigations that the quality of ground water is of nearly equal importance to quantity. In specifying the quality characteristics of water a complete statement requires chemical, physical and_ bacterial analyses. Griffin (1964) has discussed the quality classification of domestic, agricultural and industrial water. Electrical conductivity (EC) and its reciprocal resistivity (Rw) measurements bear a relation to the concentration of all inorganic constituents present in a water sample. Such measurements are principally a function of the mobilities and concentrations of the various ions in solution at a given temperature. The simple EC or Ry determination is the best single field method for assessing water quality. EC has become a frequently measured hydrogeological parameter. The parameter Rw is employed in the surface and subsurface electrical methods of applied geophysics in the fields of hydrogeology, mining and petroleum technology. For ie in ohm metres and EC in micromhos per cm. 10,000 Senor The term “‘salinity’’ of a water refers to its total soluble salt content in parts per million (ppm) by weight. A concentration of one ppm is equivalent to one milligram per litre or 0-07 grains per Imperial gallon. A frequent procedure in applied geophysics is the estimation of salinity from Ry determinations. Less commonly, Rw values are calculated from salinity information. In this paper estimation methods will be con- sidered. The estimation accuracy of some methods will be investigated by applying the methods to published data on New South Wales groundwaters. B Much work remains to be done in correlating Ry and Ry—lIonic Concentration and Composition The ion composition and ion concentration of underground water are both highly variable. With depth the temperature of such water can vary significantly. Ry varies with concentration in that it affects the activities and degree of dissociation of the various ions present in solution. Jonic mobility increases with tempe- rature, hence an inverse relation exists between Ry and temperature. 70,000 4000 NeC! pom, ——» 70 7 7O 100 Rw ohm m. —» Hicy«l Variation of electrical resistivity of sodium chloride solution with concentration in p.p.m. at 25°C. (Data from International Critical Tables.) For sodium chloride solutions analytic expressions relating Ry to ion mobilities and concentrations are well known (e.g. Heiland, 1946, p. 637) but graphed relations are more suitable for routine use. The usual Ry-con- centration charts supplied on request by geophysica] well logging contractors are un- 18 D. W. EMERSON suitable for hydrogeological purposes because Ry values terminate at too low a value. In addition such charts are for pure sodium chloride solutions which are not especially common aquifer waters in New South Wales. In Fig. 1 is shown the variation of the electrical resistivity with concentration of sodium chloride solution at 25°C. The Ry values are from the International Critical Tables (1929) and cover the range of usual interest in hydrogeological work. The effect of temperature on Ry for sodium chloride solutions was determined by Arps (1953). The temperature effect is of considerable importance. Arps, whose study was necessary as discrepancies had been found in existing charts, discovered a nearly linear relationship between temperature and the ratio Correction factor —e ° 40 20 30 40 sO 60 7O 80 oO JOO Temperoture °C —. Fic. 2 Correction factor to convert Ry to 25° C. of Ry at 32°F. to Ry at ¢°F. The equation of the relationship as determined by the method of least squares was : Ry (32°)=0-022906 Rwy (¢°) [¢+6-77] In order to convert Ry measured at #,°F. to Ry at ¢,°F. the above relation reduces to: oy 4 +6°77 Rw @ (4°)=Rw @ (4) Fotg-a7 Established practice is to express Rw at 25°C. (77°F.) for comparison and interpretation. Fig. 2 gives the necessary correction factors for this. This figure should also suffice for multi-ion waters. Richards (1954) gives more precise corrections if required. For waters other than simple sodium chloride solutions (the usual case in New South Wales) different procedures are followed to obtain Rw from concentration or more commonly con- centration from Ry. For fresh waters the relative contribution to conductivity of the ion compounds other than sodium chloride becomes very important (Ono, 1959). The restivity of a solution of two or more salts depends upon the relative concentration of each and upon the tendency of the ions to join to form more complex ions having a greater mass and smaller electric charge. For waters rich in ions with mobilities different from the sodium and chloride ions, especially if they contain bi- carbonate, carbonate, sulphate and magnesium ions, the use of Fig. 1 may result in considerable error. Because of the nature of the variables involved, no simple estimation method can be entirely satisfactory for all ionic combinations and concentrations possible in aquifers. A dichotomy into a forward and an _ inverse problem is instructive. The forward problem —determining Ry from a knowledge of con- centrations of the particular ions—can be solved by employing the appropriate equations of physical chemistry. However the inverse problem—determining concentrations from Ry —is incapable of unique accurate solution without auxiliary information on the type and quantity of ions present. The inverse problem is the real one in ground water geophysics. Reliable auxiliary ionic data are rarely available. To facilitate work in practice, a given relation is usually employed for the solution of both the forward and inverse problem. Some R, Estimation Methods Conaghan and Harrison (1956), from chemical analyses and conductivity measurements on the waters of twenty five wells and eight surface waters in the Upper Hunter area of New South Wales, concluded that the following empirical equation obtained : 15-4Cl where Cl is the chloride anion concentration. Conaghan and Harrison pioneered the use and development of the EC parameter in ground- water investigations. Their 1956 publication is an abridged version of an unpublished New South Wales Geological Survey Report. In the Report pertinent physical-chemical relations are discussed and a thorough review of the literature to that date (1948) is included. An estimating formula commonly used by groundwater workers for Rw in the range of 2 to 100 ohm m. is Ry=100/T (Todd, 1959, p. 181) where T is the ionic sum ie. half the sum of anions and cations in equivalents per million (epm). One epm of an element or ion is exactly equal in combining power to one epm of another element or ion. The epm values are obtained by dividing the ppm concentration Conc. (ppm)=1-14 ECia9°c) AQUIFER WATER RESISTIVITY—SALINITY RELATIONS values of the constituents by the appropriate equivalent or combining weights. Another well known estimation method for the same resistivity range is Rw=6500/conc. (ppm). An approxi- mation sometimes used in Australia is Ry= 5000/conc. at 20°C (Wiebanga and Jesson, 1962). 10,000 Jones & Buford — Sodium bicarbonate woters Jones & Buford —-—* Average noturo/ woters Jones & Buford ——— Sodium chlorige wolers Concentration ppm. ———» chOras ——— Average noturo/ woters _-- Dyson & Wiebonge R 6500 ao Kw t tom Rw ohm nS Fic. 3 Some Ry-Ionic concentration relations (25° C.). Dunlap and Hawthorne (1951) developed a method for reducing the chemical composition to an equivalent sodium chloride composition. The ppm concentration of each ion is reduced to an equivalent sodium chloride salinity by means of conversion factors. For the sodium, potassium, calcium, magnesium, chlorine, sul- phate, bicarbonate, carbonate and hydroxyl ions the factors are 1-00, 1:00, 0°95, 2-00, 1:00, 0-50, 0-27, 1-26 and 5-10 respectively. The factor for sulphate is raised to 0-55 when total concentration exceeds 10,000 ppm. Martin (1958) determined that the Dunlap and Haw- thorne factors were relatively independent of temperature but varied considerably with changes in concentration. Richards (1954) investigated a_ relation between Ry and the concentration of various average natural waters. This relation is plotted in Fig. 3. Jones and Buford (1951) presented Ry-salinity data on sodium chloride, average natural and sodium bicarbonate waters. These data also are shown in Fig. 3. Dyson and Wiebanga (1957) found : log conc. (ppm)-+0-:92 log Rw=3-68 This relation was established for some Northern 19 Territory waters at 20°C. These waters had a relatively high sulphate and chloride content when concentrations exceeded 1600 ppm and a relatively high carbonate content when con- centrations were less than 500 ppm. Their relation is shown in Fig. 3. Logan (1961) devised an empirical estimation technique in which only the nature of the principal anion and the epm value are con- sidered. Logan’s data for ‘‘ normal” (bicar- bonate), chloride and sulphate waters are presented in Fig. 4. Discussion Of the estimation methods mentioned, the 100/T, Dunlap and Hawthorne, Logan—normal, 6400/ppm and Jones and Buford average natural relations are deemed methods of general utility and applicability. To test the efficacy of these general estimation methods forty three chemically analysed groundwaters were chosen at random from the published data of Horbach (1965, 1967) and Conaghan (1961). In addition one water was taken from Conaghan and Harrison (1956) and one water from the Water Conservation and Irrigation Commission’s data on groundwaters of the Forbes district. The results of EC measurements on all waters were also available. 1000 100 6 Ss w Es 25 Noa Or Costu on 5 10 leg ay al eaaESTT UTE SESE | 5 Normal w waters Sulphate waters _ Chloride waters to 1000 =E.C. mbhos/ern. 19000 —> 700.000 100 =— 10 Rw ohm m —0i Fic. 4 Rw (and E.C.) at 25° C.—Ionic sum relationships. (After Logan, 1961.) In the Appendix the sample number, Ry value and dominant anion of each water are given. It will be noted that the bicarbonate anion is dominant in twenty seven of the 20 D. W. EMERSON samples and the chloride ion dominates in the remaining eighteen. Ry values range from 0:45 to 64:5 ohm m. Waters from deep and shallow bores in the Sydney, Murray, Clarence and Great Artesian Basins together with waters from shallow bores in coastal and inland river deposits are included. TABLE 1 Percent Percent Estimation Method Average Average Deviation Bias 100 T : co Dunlap and Hawthorne 10 —4 Logan 11 +11 6400 14 _ ppm Jones and Buford 17 —16 In Table 1, for each of the five general estimation methods, the average deviation of calculated from measured Ry values are listed with the average bias of the calculated values. To provide a better comparison of the methods, the results are given in the form of average percentage errors. An estimation error of 1-0 ohm m. for a measured Ry of 4:0 ohm m. would not be as serious as an error of equal magnitude for an Rw of 2-0 ohm m. It can be seen that the 100/T method was the most satisfactory followed by the Dunlap and Hawthorne and Logan-normal methods. It should be remarked that an 8°% average devia- tion and a +7% bias was obtained when the Logan-normal curve was used for the twenty seven bicarbonate waters only. An 8% average deviation and a +8°%% bias were obtained when the Logan-chloride curve was applied to the eighteen chloride waters only. These methods require knowledge of the nature and quantity of ions present. The 6400/ppm and Jones and Buford average natural methods gave poorer results. These two methods require a knowledge of quantity of ions and an indication that the water is not of abnormal type. In the examples the forward problem has been considered. Attempts to solve the inverse problem would lead to even larger uncertainties in the absence of data on the nature and amounts of ions in the water. For the solution of the inverse problem it is considered reasonable to predicate : 1. When the nature of the dominant anion of the waters in question is unknown and no assumptions as to the dominant anion nature are possible then, until a better correlation is available, the 6400/ppm relation should be used if — concentration in ppm is required. To obtain — concentration in epm the Ry= “ or Logan iE normal curve should be used. It should be remembered that to convert epm to ppm requires some assumption of ions present in the water. 2. When some knowledge as to the nature of the dominant anion is available the Logan curves for a particular dominant anion should be used. 3. In particular localities for particular aquifers where the Ry-ppm equation is known, e.g. the Conaghan and Harrison relation for the Upper Hunter groundwaters, then such a relation should be used. In New South Wales the state of knowledge as indicated by statement 2 above would obtain at the present time for most areas. As chemical analyses and Ry data accumulate the situation will improve. Generally, groundwater from a particular aquifer in a specific area is nearly constant in chemical quality. Dissolved solids present can be correlated with the mineralogy, texture and structure of an aquifer, the position of the well with respect to recharge areas and the rate of movement of interstitial waters which would depend on climate, surface topography and subsurface structure. Extensive psammitic aquifers commonly yield water of a fairly uniform chemical composition or a composition that changes uniformly with location. In most areas systematic changes, if any, in the family of ions generally accompany changes in the total dissolved solids. Thus the interpretation of groundwater Ry values in terms of probable concentrations and kinds of important ions is usually feasible by geological and geographic interpolation and by extra- polation between or from available well control. Conclusions Whilst no detailed conclusions can be drawn from the results of the methods’ applications to only forty five New South Wales waters the following observations are considered valid : 1. Large errors may result in attempts to solve both the forward and inverse problems if no information is available as to the nature of dissolved solids in waters. AQUIFER WATER RESISTIVITY—SALINITY RELATIONS 21 2. Every effort should be made to obtain the requisite ionic information before interpretations are commenced. 8. Ry-concentration relations should be formu- lated for particular areas as the necessary data become available. Appendix New South Wales Department of Mines Chemical Laboratory sample number; mea- sured Ry value ohm metres at 25°C ; dominant anion: B bicarbonate, C chloride. 63/479, 3-5, C; 63/486, 1-1, C; 63/490, 3°3, C; 63/500, 1-3, C; 63/513, 34:6, B; 62/566, 33-3, B; 62/568, 64-5, B; 63/4106, 6:3, C; 63/4108, 56-8, C; 63/5201, 23-6, B; 62/2093, 16-8, B; 62/483, 2-8, B; 63/2951, 0-67, C; 63/2965, 9:2, B; 63/4955, 15-3, B; 63/4956, 4-0, B; 62/321, 18-6, B; 62/1630, 2o-2, B; 62/1776, 9-2, C; 63/2655, 10-9, C; 63/3187, 1-7, B; 63/4623, 39-1, B; 63/5166, 1:3, B; 62/2148, 9-1, B; 62/2149, 8-5, B; 62/2150, 6-7, B; 62/2151, 9-1, B; 64/1776, 1-6, C; 64/1780, 0-6, C; 64/1783, 5-9, B; 64/2148, 0:45, C; 64/2795, 1-1, C; 64/2807, 41-5, B; 64/362, 19-1, B; 64/564, 41-5, C; 64/4598, 0:88, C; 64/542, 6-9, B; 64/543, 9-9, B ; 58/1037, 21-2, B; 58/1668, 3-7,C ; 58/1017, 11-9, B; 58/2049, 2-1, C; 58/1666, 5-6, C; 48/2538, 8-8, B; W.C.I.C. Bore 14824, 16-1, B. References Arps, J. J., 1953. The effect of temperature.on the density and electrical resistivity of sodium chloride solutions. Tech. Note 195, Pety. Trans. A.I.M.E., 198, 327-330. CoNAGHAN, H. F., and Harrison, E. J., 1956. Upper Hunter groundwater investigations. Part III. Field conductivity measurement in groundwater investigation. Ann. Rept. Dept. Min. N.S.W. 1948, 107. ConaGHAN, H. F., 1961. Water Analysis. Dept. Min. N.S.W. Tech. Rept., 6, 1958, 125-130. DunwaPp, H. F., and HAWTHORNE, R. R., 1951. The calculation of water resistivities from chemical analysis. Tvans. A.I.M.E., 192, 373-375. Dyson, D. F., and WIEBANGA, W. A., 1957. Final report on geophysical investigations of under- ground water, Alice Springs, N.T. 1956. Buy. Min, Res. Rec., 1957/89. GRIFFIN, R. J., 1964. Quality classification of water. Geol. Surv. N.S.W. Rept. No. 17, 10 pp. HEILAND, C. A., 1946. Geophysical Exploration, Prentice Hall, New York, 637. Horsacu, D., 1965. Selected records of the Chemical Laboratory for the years 1962 and 1963. Dept. Min. N.S.W. Chem. Lab. Rept. No. 7, 31 pp. Horspacu, D., 1967. Selected records of the Chemical Laboratory for the year 1964. Dept. Min. N.S.W. Chem. Lab. Rept. No. 12, 21 pp. Jonres, P. H., and Burorp, T. B., 1951. Electric logging applied to ground water exploration. Geophysics, 16, 115-139. LoGaN, J., 1961. Estimation of electrical conductivity from chemical analyses of natural waters. /. Geophys. Research, 66, 2479-2483. MarTIN, M., 1958. Relation entre la resistivite des eaux et leur composition chimique. Inst. francais petrole Rev.et Annales combustibles liquides, 13, (6), 985. Ono, Y., 1959. of forrnation water. 10, No. 7, 617-626. RIcHARDS, L. A., Ed., 1954. Diagnosis and improve- ment of saline and alkaline soils. U.S. Dept. Agr. Handbook Co., 160 pp. Various problems on the resistivity Japan. Geol. Surv. Buil., Topp, D. K., 1959. Ground water hydrology. John Wiley and Sons Inc., New York, 336 pp. WIEBANGA, W. A., and JEsSON, E. E., 1962. Geo- physical exploration for underground water. Bur. Min. Res. Rec. 1962/172, 12 pp. Journal and Proceedings, Royal Society of New South Wales, Vel. 101, pp. 23-36, 1967 The Stratigraphy of the Putty-Upper Colo Area, Sydney Basin, N.S.W. MALCOLM C. GALLOWAY* Department of Geology and Geophysics, University of Sydney, N.S.W. ABSTRACT.—The outcropping sediments of the area mapped are of Triassic age and include the Wianamatta Group, Hawkesbury Sandstone and Narrabeen Group. The Narrabeen Group represents the oldest outcropping sediments of the area and up to 600 feet are exposed, though, only rarely are more than 300 feet exposed at any one locality. It consists of labile and sub labile sandstone, siltstone, mudstone and scattered chocolate claystone. The overlying Hawkesbury Sandstone attains a maximum thickness of 950 to 1000 feet frorn Webbs Creek to Upper Colo and extends over almost the whole of the area mnapped. It consists of quartz sandstone and minor scattered sub-labile sandstone with rare siltstone interbeds up to 30 feet thick. Of the Wianamatta Group only a veneer remains. It is restricted in outcrop to the vicinity of the Putty Road from the Culoul Range southward. flaggy, labile sandstone. It consists of siltstone and fine grained Structurally the area is dominated by the Lapstone Monocline extending from Upper Colo to Kindarun Mountain. Gentle eastern dips occur west of the Lapstone Monocline and a series of open folds plunging southwards occur east of the Lapstone Monocline. Basic igneous necks and caps are scattered throughout the area but are most common north of 33°00’S in the vicinity of Putty and Kindarun Mountain. Introduction The earliest contribution to the knowledge of the geology of the area was that of Carne (1908) who worked over the western half of the area north of 33°15’S latitude and described many basic plugs and caps of the area. He also refers to a few chocolate claystone localities. Lovering (1954) recorded the presence of Ashfield shale capping the Wheelbarrow Ridge near Colo Heights. Crook (1956) studied the Kurrajong-Grose River district and by air photo interpretation extended his work to cover the country west of the Putty Road and south of 33°15’S. The work was used in compiling the accompanying maps, but numerous detailed modifications, as a result of the author’s field work, were necessary. Raggatt (1938) studied the Triassic sediments east of Mangrove Creek. His sub-divisions of the Narrabeen Group could not be applied in the area covered by this paper. McGarry and Rose, of Australian Oil and Gas Corporation carried out reconnaissance work in the Putty and Howes Valley districts. The results of this work are unpublished. * Present address, Bureau of Mineral Resources, Geology and Geophysics, Canberra, A.C.T. } In this paper the 1: 63,360 sheet areas mapped are :—Mount Yengo, Mellong, St. Albans. This covers part of both the Sydney and Singleton 1: 250,000 sheet areas. Regional Stratigraphy The Triassic sediments are the oldest outcropping rocks in the area studied and consist, in general, of quartzose and sub labile sandstone with less common siltstone and mudstone. Subdivisions of the sequence in areas adjoining that studied have been proposed by Lovering (1954) for the Wianamatta Group, Crook (1956) for the Narrabeen Group of the Kurrajong-Grose River district, and Raggatt (1938) for the Narrabeen Group of the Gosford- Morisset district. Of these, Lovering’s and Crook’s subdivisions have been found to be applicable in the area studied. The sequence examined is summarised in the following table. Thicknesses quoted above are maxima for the area studied and are field measured sections with the exception of the Grose Sandstone which was the thickness recorded in Exoil A.O.G., Kurrajong Heights No. 1 well*, the bore data being made available by the Bureau of Mineral Resources in accordance with the Petroleum Search Subsidy Act. Figures 2 and 3 show a number of measured sections with the probable NS and EW forma- tional equivalents. These are discussed under “ Correlation and Comments ”’. * Following their first appearance in the text, wells will be referred to only by the name of the locality after which they are named. 24 The outcropping Triassic rocks of the area are known, from A.O.G., Mount Murwin No. 1 and A.O.G., Mellong No. 1, to be underlain by the “‘ Upper Coal Measures ”’. It is most probable that these in turn are underlain by “‘ Upper Marine ’”’ sediments, as they outcrop in the Hunter Valley and along the western edge of TABLE 1 Age Stratigraphy Quaternary— Sands and gravels along the courses Recent of present streams Post Triassic Basic volcanics, dykes, necks and flows Ah Ashfield Shale of the Wianamatta R Group (75 feet) I eee ae a an 2 el A Hawkesbury Sandstone (950 feet) S S Narrabeen Group I West East Cc Burralow Formation Undifferentiated (450 feet) Grose Sandstone Undifferentiated (1385 feet) Caley Formation Not observed (217 feet) the basin; they were also encountered in Kulnura No. 1 and the Kurrajong Heights wells. Below the “‘ Upper Marine ”’ sediments a southern extension of the Greta Coal measures and the ‘‘ Lower Marine’ Dalwood Group may underlie the northern parts of the area, but their absence in the Kurrajong well possibly places limits on their southward extension. Underlying the Permian sequence it is probable that basic, then older acid volcanics occur of possible Carboniferous age. From outcrop in the Hunter Valley, as well as the A.O.G. Loder No. 1 well, and Planet’s East Maitland No. 1 well, it is evident that the Dalwood Group contains a considerable thickness of basalt and tuffs and overlies the Carboniferous acid volcanics of the Upper Kuttung Group. Along the western margin of the basin the tuffs at Rylestone overlie the Upper Devonian sandstone unconformably and are conformably overlain by the Permian sediments (Personal communication, Dr. A. J. T. Wright), and have lithological similarities with the volcanics of the Upper Kuttung Group (Day, 1961). South of the area studied, A.O.G., Kirkham No. 1 and the Kurrajong Heights wells (Stuntz e¢ al., 1963) (Stuntz, 1965) terminated in basic and acid volcanics. MALCOLM C. GALLOWAY Formation Descriptions NARRABEEN GROUP, WILKINSON 1887 This group occurs throughout the whole of the area studied, outcrops being more common toward the north. The area studied lies between two areas which have had different stratigraphic subdivisions recognised within them, those of Raggatt east of Mangrove Creek, and those of Crook south- wards from Upper Colo. Fig. 1 shows the probable E-W correlation across the basin. East of the Mount Murwin-Webbs Creek anticlines, individual sandstones are up to 100 feet thick, but are not persistent; they thicken or thin and split over short distances as indicated by the E-W Sections 4 to 19 on Fig. 2, between Mogo Hill and Melon Creek, west of Higher Macdonald. Along the Webbs Creek and Macdonald River systems south of 33°15’S, less than 150 feet of the Group exposed; north of 33°12’S 300 to 600 feet of the Group is exposed, however, neither Crook’s nor Raggatt’s subdivisions are recognisable in this area. This is evident from examination of the stratigraphic sections mea- sured in the district from which it can be seen that correlation between successive sections is most difficult (Fig. 3). North from Colo, Crook’s subdivisions are workable, but only to the west of the Webbs Creek and Mount Murwin anticlines. Following these formations as defined by Crook is progres- sively more difficult towards the north. At 33°00’S it is evident that the dominantly shale lithologies of the Burralow Formation are being replaced by up to 50°% sandstone, however, the Grose Sandstone provides a recognisable base for the Formation. A persistant, prominent sandstone about halfway between the base of the Hawkesbury Sandstone and the top of the Grose Sandstone, is possibly a correlate of the Tabarag Sandstone Member and can be followed from 33°15’S to 33°06’S. At this point the increasing occurrence of additional sand- stone units makes it progressively more difficult to distinguish the member. At Mount Wirraba. and west of it, the Burralow Formation is not recognisable, the top of the Narrabeen Group being almost all sandstone (See Section 8, Fig. 3). To the east of the Mount Murwin-Webbs Creek anticlines no subdivisions within the group have been applied. Chocolate claystones are common throughout the area but are usually very poorly exposed, or are concealed. — a STRATIGRAPHY OF PUTTY-UPPER COLO AREA, SYDNEY BASIN 25 WESTERN AREA CENTRAL AREA NORTH COAST W.of Mt Murwin- anon cron tn Webbs Creek Macdonald River Anticlines Valley | (Nomenclature ( Nomenclature | Raggatt 1938) Grook 1956 ) | BURRALOW UNDIFFERENTIATED | GOSFORD FORMATION NARRABEEN GROUP | FORMATION COLLAROY CLAYSTONE GROSE SANDSTONE TU6GERAH FORMATION MUNMORAH | CONGLOMERATE CALEY FORMATION Vertical Scale : 500ft. to an inch Fic. 1—Probable E-W correlation. For descriptive purposes the area will be CALEY FORMATION, CROOK 1956 divided into two sections, one west of the Webbs Although the area where this formation was Creek-Mount Murwin Anticline where Crook’s examined is some miles north from the nearest subdivisions can be applied, and a second, locality where Crook records it, it so closely east of the anticline where no subdivisions resembles his description that there is little will be applied. doubt that it is the same formation. 26 MALCOLM C. It outcrops only in the extreme west of the area mapped where it conformably overlies the Lithgow Coal Measures. During a brief recon- naissance trip down the Wolgan and Capertee Valleys it was examined and found to consist of interbedded grey mudstone and siltstone up to 15 feet thick with scattered labile sandstone, commonly three to six feet thick, but rarely up to 15 feet thick. Current bedding was not observed at Wolgan Gap, but both planar and festoon bedding was present at Newnes in the Wolgan Valley. The sandstones were fine to coarse grained and, in addition to quartz, contained a considerable percentage of rock fragments; these were white, angular and deeply weathered in the outcrop samples examined ; the cement consists of white clay. Bands of pebble conglomerate, especially at Wolgan Gap, contained abundant rock frag- ments, most of which were low grade meta- sediments that are readily available from the Palaeozoic rocks further west. The base of the formation coincides with the top of the Katoomba seam and it is overlain by the Grose Sandstone. At the top of the formation, green and chocolate claystones commonly occur, there being 15 feet at Wolgan Gap and 32 feet at Newnes. The formation thickens from 135 feet at Wolgan Gap to 217 feet at Newnes over an east-west distance of only eight miles, clearly showing the rapid thickening basinwards. The thickness recorded in the Kurrajong Heights well was 250 feet, revealing only slight thickening basinwards from Newnes, while the Mount Murwin well records 483 feet, almost double the thickness at Kurrajong Heights. GROSE SANDSTONE, CROOK 1956 The Grose Sandstone consists of labile sandstone with scattered discontinuous siltstone interbeds. In the area studied it outcrops only in the gorge of the Colo River and its tributaries. It is exposed well north of Upper Colo on the Colo River, west of Six Brothers Trig near the junction of the Capertee River and Wollemi Creek (730 feet exposed). A second locality is along the military track for four wheel drive vehicles where it runs for about one mile up- stream along Wollemi Creek from the junction with Putty Creek, and, thirdly, west of Cobcroft Trig where 372 feet are exposed. In the valleys of the Wolgan and Capertee a considerable thickness of the formation is to be seen. Weathering has removed all signs of the formerly overlying Burralow Formation or Hawkesbury Sandstone in this area, so the following sections GALLOWAY represent only the eroded remnants of the formation. At Wolgan Gap, 230 feet remains, overlying the Caley Formation. It consists of sandstone showing common planar type current bedding from one foot six inches thick to three feet thick, and, particularly near the base, scattered thinner planar type current bedded units from three inches to 12 inches thick. At Newnes, 737 feet of the formation remains, of which the lower 288 feet closely resemble that seen at Wolgan Gap. Above this lower 288 feet there is a break in outcrop for 44 feet in which sandstone talus was so common, that no suggestion of siltstone, claystone, or any other rock type could be found in situ. This interval of no outcrop is sufficiently widespread to be recognisable on either side of the Wolgan fi Gorge and can be seen extending down stream > to the Devil’s Pinch (Glen Davis, 278005). Above this break a further 230 feet of sandstone occurs. It is characterised by the predominance of planar type current bedded units generally from three to nine inches thick with scattered beds up to one foot six inches thick. This contrasts with the thicker units of the lower 288 feet where beds 10 to 20 feet thick predominate. Where the Grose Sandstone has been examined along the Colo River and Wollemi Creek, current bedded units up to one foot thick are predominant with rare units up to three feet thick. On the basis of field work, no estimate can be made of the maximum thickness of the formation. In two localities over 700 feet are exposed—737 feet at Newnes and 730 feet at the junction of the Colo and Capertee Rivers ; these sections are incomplete. In the Kurrajong Heights and Mount Murwin wells the thickness of the sandstone correlatable with the Grose Sandstone is 1385 feet and 1335 feet respectively. About 1200 feet of the formation occur in the A.O.G. Mellong well (personal communication, J. Stuntz, A.O.G.). These thicknesses are about twice the maximum of 700 feet proposed by Crook from two partial sections measured in the Grose Valley, where Crook’s section shows that the formation is thinning westward. BURRALOW FORMATION, CROOK 1956 This formation outcrops extensively to the west of the Putty Road, and is the uppermost formation in the Narrabeen Group. It overlies the Grose Sandstone, is overlain by the Hawkes- bury Sandstone and is from 300 to 450 feet thick. It is distinguishable from the Hawkesbury Sandstone by the dominantly siltstone and STRATIGRAPHY OF PUTTY—-UPPER COLO AREA, SYDNEY BASIN claystone lithologies with scattered lithic sand- stone and, north of the 33°10’S latitude, by the presence within the Burralow Formation of scattered beds of characteristic polymictic conglomerate. These conglomerates are rarely more than one pebble thick where observed in Mellong Range-St. Albans areas, but to the north the units become thicker and more common until in the Howes Mountain-Sugar- loaf Hill (39319404) area they are up to 12 feet thick. In the south the pebbles consist mainly of black, red, pastel blue and green jasper with some pale smoky grey, milky and colourless quartz pebbles of up to two inches diameter. They are slightly elongate and well rounded. At Putty and Mogo Hill (Section 19) pebbles of obvious acid igneous origin and other weathered fine grained rock fragments of “chalky” appearance occur. At Reedy Creek, further north, scattered quartz porphyry pebbles, and increasing amounts of weathered “ chalky ”’ rock fragments occur with less jasper and few milky or colourless quartz pebbles. At Howes Mountain, quartz, porphyry and acid volcanic cobbles occur in beds which are commonly two to three feet thick and rarely as much as 12 feet thick. Lithic sandstones are common only north of the Culoul Range, south of this, quartz sand- stones predominate; at Upper Colo these quartz sandstones are very similar, even in thin section, to those of the Hawkesbury Sandstone. Current bedding of both the planar and festoon type are common in the sandstones of the formation. About 150 to 200 feet below the Hawkesbury Sandstone, a sandstone occurs which is possibly equivalent to the Tabarag Sandstone Member of Crook (1956). It can be followed from the Culoul Range to 33°05’'S, but north of this point the greater proportion of sandstone in the section makes the Member increasingly difficult to distinguish. To the west, the formation as a whole becomes increasingly difficult to recognise because of the increasing proportion of sandstone present. At the western edge of the area, between 33°00’S and 33°15’S the proportion of sandstone is so great that the formation is extremely difficult to distinguish from the Grose Sandstone below or the Hawkesbury Sandstone above. The boundaries shown between 33°00’S and 33°15’S were determined from aerial photo interpretation with known ground control in various localities. The map shows both the lower and upper boundaries to its western edge, but the Grose Sandstone-Burralow For- -Mation boundary is very approximate at the 27 western edge and is practically unrecognisable in the field. The Hawkesbury-Narrabeen boundary in the field is a sandstone-sandstone boundary which, even in the most favourable circumstances, is subject to interpretation. The total thickness of the Burralow Formation varies from 300 feet to 450 feet. Whether the formation thins out or passes into sandstone towards the west is debatable, but the author thinks that passing into sandstone westwards is not only to be expected, but is confirmed by the Section 8 measured at Mount Wirraba. Here, the Hawkesbury-Narrabeen boundary, based on the change in sandstone types is at 1550 feet A.S.L., whereas the top of the Upper- most chocolate claystone is at 1260 feet A.S.L. Polymictic conglomerates were not found. Above the chocolate claystone scattered grey siltstone occurs, but sandstone is more common up to the proposed base of the Hawkesbury Sandstone, above which the massive and current bedded quartz sandstone of the formation continues to the base of the basalt capping Mount Wirraba. UNDIFFERENTIATED NARRABEEN GROUP The undifferentiated Narrabeen Group is to be found east of the Webbs Creek and Mount Murwin anticlines. Similar lithologies to those observed in the Burralow Formation are observed also along the Macdonald River and its tributaries and the upper reaches of Webbs Creek near its junction with Rush Creek. They consist of lithic sandstone, siltstone, chocolate and green claystone and polymictic conglo- merate. Sandstones up to 100 feet thick occur, rarely with a chocolate claystone band up to two feet thick interbedded with the sandstone. An example of this can be seen in the measured sections between the Ivory Creek-Melon Creek junction and Mogo Hill (Sections 14, 15, and 16, Fig. 3). Chocolate claystone can be found in any section examined ; it is not confined to any particular horizon and is just as common 500 feet below the Hawkesbury Sandstone as 100 feet below it. Polymictic conglomerates occur, but they have not been seen south of St. Albans. This is probably because of the small stratigraphic interval exposed. The most southern locality from which they have been found is one to two miles north of St. Albans and they occur in thicker and more numerous beds the further north one seeks them. Rarely is more than 100 feet of the Group exposed along the Macdonald River south of St. Albans. Around Upper and Higher Macdonald the conglomerates are sufficiently common to be 28 MALCOLM C. very useful in determining the base of the Hawkesbury Sandstone. A description of the pebbles and their geographic variation is given in the petrographic description of the Burralow Formation and will appear in a forthcoming paper. The sandstones within the exposed part of the Narrabeen Group are discontinuous, as demonstrated by the seven stratigraphic sections measured between Mogo Hill in the east and Melon Creek in the west (Fig. 3) the section line being about 13 miles in length. A 100 feet thick sandstone body will split into a number of smaller units and lens out into shale over very short distances. It is doubted that even these 100 feet thick, apparently non shaley sandstone bodies would, if examined in a 100°% exposure or in a diamond drill core, be found to be devoid of shale bands. Sedimentary structures, including both festoon and planar current bedding and, in one locality current ripples, were observed. The current ripples, which have not been observed elsewhere in the area, occur about two miles north of Higher Macdonald in the bed of Thompsons Creek. The planar cosets of current bedding can be as much as 10 or 15 feet thick, though these thicker units are by no means as common as in the Hawkesbury Sandstone. In the Fernances-Mogo Hill area, the base of the Hawkesbury Sandstone becomes very difficult to recognise. This is because it is commonly a sandstone-sandstone boundary. At Mogo Hill polymictic conglomerates occur 90 feet below a 130 feet thick sandstone section. The highest conglomerates are usually no more than 70 or 100 feet below the top of the Narra- been Group, so the base of the Hawkesbury Sandstone would be placed below the 130 feet sandstone section. However, the sandstones appear more lithic than is normal in Hawkesbury Sandstone and in thin section contain only 45°% quartz—the remainder being rock frag- ments and matrix. The boundary is probably at the top of the siltstone which overlies the 130 feet of sandstone resulting in the topmost conglomerates being 270 feet below the Hawkes- bury base. Erosion of the top of the Group before deposition of the Hawkesbury Sandstone is evident in the lower reaches of the Macdonald River near its junction with the Hawkesbury River. Washouts over 100 feet deep and covering an area of half a square mile are recognisable, in particular at (39458775). They have not been recognised elsewhere in the area. GALLOWAY HAWKESBURY SANDSTONE, CLARKE 1848 This formation occurs throughout the whole . _ ; of the area studied. It consists of quartz sand- ~ stones which are light grey to creamy white in colour with a white clay cement. There is always abundant colourless to milky subangular quartz with rare scattered graphite and dark black and brown grains present. The grain size is domi- nantly medium to coarse but may be fine or very coarse. Two distinct types of conglomerate occur. The first type consists of masses of angular, often rectangular, granules and pebbles of quartz ranging from one-quarter to three- quarters of an inch in diameter; the thickness of a single unit often being as much as 15 feet. These units often grade from pebble size at the base to fine sand size at the top. The second type of conglomerate consists of well rounded oval pebbles from one to two inches in diameter with rare ones up to six inches in diameter. They are commonly composed of colourless to milky quartz with very rare smoky grey pebbles. The units are very thin, usually only one pebble thick, units of two or three layers were rare. A small percentage of silstone occurs; it is usually mid-grey to buff in colour and rarely exceeds 20 feet in thickness. Bands up to four feet thick are to be found in any section mea- sured. Total thickness of siltstone in a 500-foot section is usually about 5°% and rarely exceeds 1OeZ: Compared with the Wianamatta Group, siltstone, those of the Hawkesbury Sandstone are much lighter grey in colour, are much — more sandy and do not form dense black soils or support prolific vegetation. Notable occur- rences of these shales are along the Old Great North Road leading NNW from Wisemans Ferry near the road junction to Putty township on the Putty Road and about halfway along the Upper Colo-Colo Heights road. In all cases they overlie and are overlain by undeniable Hawkesbury Sandstone. Current bedding is very common in the Hawkesbury Sandstone. It is dominantly of the planar or torrential type and occurs in units commonly up to six or rarely eight feet thick but may be even thicker. Rare beds of the festoon type occur; they average from three to nine inches in thickness and seldom exceed two feet. The angle of dip of foresets is commonly 18 to 24 degrees, but ranges from 15 to 30 degrees. The thinner beds are commonly found in finer grained sandstone and the dips of the foresets are at a lower angle than the thicker STRATIGRAPHY OF PUTTY-UPPER COLO AREA, SYDNEY BASIN 29 units which are usually more coarse grained and made up of granule or even pebble size material. The foresets dip predominantly toward the NE and occasionally to the north; rarely they may have quite anomalous dips. In such localities, additional observations at higher and lower stratigraphic levels invariably show that the majority of the units dip to the NE. This predominant dip direction of foresets in the planar type of current bedding is maintained throughout the whole of the area from Colo and Wisemans Ferry in the south to Howes Mountain in the north. The total thickness of the formation varies greatly over the area. The greatest thickness appears to be near the junction of Rush Creek and Webbs Creek where the base is at 170 feet, while the hill immediately south is still Hawkes- bury Sandstone at its crest at 1020 feet, giving a total thickness of over 950 feet for the for- mation. This is the maximum thickness recorded for this formation in the Sydney Basin. Further to the NW, between Dooli Creek and the Culoul Range, the thickness appears to be about 750 feet, but the dip thereabouts is not clear and the total thickness could be less. Further south, at Colo heights between the base of the Wianamatta Group and the Colo River, 855 feet of the formation is exposed—the section being measured along strike over a distance of three miles. Consideration of structure contours determined on the base of the Hawkesbury Sandstone and Wianamatta Group and the distance between the base of the section and the known base of the formation at Upper Colo, suggests that a further 50 to 100 feet of the formation is probably unexposed. Still further south the Kurrajong well encountered 750 feet of Hawkesbury Sandstone. The thickness of the formation above the well site is uncertain, because of the closeness of the Kurrajong Fault, but it would not be more than 50 feet. Thus the thickness of the formation would be about 800 feet at Kurrajong Heights. Further west, near Mount Tomah, between the base of the Wianamatta Group on the Bell Road and the Hawkesbury Sandstone base in Bowens Creek, the formation is only about 420 feet thick. These fgures show a rapid thickenirg to the east from 420 feet near Mount Tomah to 750 to 800 feet alorg the Kurrajong Heights-Culoul Range line followed by a further thickening to over 950 feet at Colo Heights and the Webbs Creek-Rush Creek junction. North of the Culoul Range it is impossible to measure the thickness of the formation because of the absence of Wianamatta Group. However, at Putty, between the Hawkesbury Sandstone base in Snake Valley and the Putty Rock trig, which is still in Hawkesbury Sand- stone, a thickness of 486 feet remains. Still farther north, between Darkey trig and the Hawkesbury base in Darkey Creek, 321 feet of the formation remains. A mile or so further north the southern dip takes the base of the formation above general ground level. WIANAMATTA GROUP, CLARKE 1848 Only a veneer of this group remains and occurs as ridge cappings in the area studied. It consists of dark grey fine grained siltstone with interbeds of thin lithic sandstone up to two feet thick; flaggy coarse siltstone and very fine grained sandstone one to three inches thick are common, separated by soft fissile shale. The group forms a characteristic dark black soil which supports very dense vegetation. It outcrops in isolated patches along the Wheel- barrow Ridge which runs between Portland and Colo Heights and along the Culoul Range. An outlier occurs around Hockeys Flagstaff trig to the NW of the Culoul Range. The group outcrops thinly along the tops of these ridges. Often there is no way of deter- mining whether the outcrops represent the Passage Beds (Lovering, 1954) or Ashfield Shale (op. cit.). This applies in particular along the Culoul Range. However, around Colo Heights and Hockeys Flagstaff Trig (36978985) where 50 to 75 feet of the Group occurs, there seem to be no Passage Beds, but instead there is an abrupt change from Hawkesbury Sandstone into Wianamatta Group siltstone. Lovering suggested (P175) that these occurrences probably belong to equivalents of the Ashfield Shale. Additional siltstone occurrences to the north of Hockeys Flagstaff trig on the ridge at (36978985) and along the western end of the Parr Spur track, especially around Dry Rock (36458809) and to the south of it to (36358785) are not regarded as belonging to the Wianamatta Group. Many sandstone floaters occur through the siltstone which does not yield the black soil or vegetation characteristic of the Wiana- matta Group and has a total thickness of only a few feet. These occurrences probably represent siltstone lenses high in the Hawkesbury Sand- stone. The siltstone along the Old Great North Road, north east of Wisemans Ferry is overlain in places by up to 50 feet of undoubted Hawkes- bury Sandstone. 30 Criteria for Recognition of the Hawkesbury-Narrabeen Boundary The main mapping horizon in the area studied was the base of the Hawkesbury Sand- stone. It was the only boundary sufficiently widespread to be of practical value. The base of the Wianamatta Group is restricted to ridge tops south of 33°15’S except for the small outlier at (36978985). A prominent siltstone horizon in the Hawkesbury Sandstone, out- cropping along the Old Great North Road NE of Wisemans Ferry, was mapped, but it was always doubtful whether the siltstone on neighbouring hill crests was from a continuous horizon or a number of separate ones. The lithologies regarded as diagnostic of the Narrabeen Group are listed below. Chocolate Claystones :—These occur throughout the whole of the area studied. They rarely outcrop other than under most favourable circumstances such as in a creek bed, a recent land slide, or, occasionally, under sandstone ledges where mechanical undercutting may reveal them. Because they outcrop so poorly they are a rather unsatisfactory basis for deter- mining the Hawkesbury-Narrabeen boundary. Polymictic Conglomerates :—These provide by far the most practical criteria for use in the field. In particular they consist of jasper pebbles which do not occur in the Hawkesbury Sand- stone and which resist erosion even when all other components have been destroyed. Where talus or soil alone can be found, jasper pebbles often remain on the surface of the ground and around tree roots. A detailed description of the jasper pebbles and the polymictic conglomerates and their geographic limits can be found in the foregoing description of the Burralow Formation. Sandstones:—A sequence of fine grained sandstones, in regular beds one to three feet thick, commonly separated by thin siltstone interbeds is regarded as typical of the Narrabeen Group. Such sandstones are commonly soft and deeply weathered. Thickly bedded coarse grained units common in the Hawkesbury Sandstone are equally common in the thicker units of the Narrabeen Group. The thinner sandstone units of the Narrabeen Group are commonly much darker in hand specimens and contain more rock fragments and ferruginous material than samples from the Hawkesbury Sandstone. One must be very cautious, as sandstones from the Hawkesbury Sandstone can have quantities of graphite, ferruginous MALCOLM C. GALLOWAY material and abundant white clay cement. A sandstone-sandstone boundary is somewhat unsatisfactory as it is always liable to different interpretations. Siltstone:—In localities such as the lower reaches of the Macdonald River, especially at Wisemans Ferry, only a few tens of feet of the Group is exposed and no chocolate claystone or polymictic conglomerate are to be found. In such localities where in excess of 50 feet of siltstone can be found underlying known Hawkesbury Sandstone, there is _ strong evidence that the base of the Hawkesbury Sandstone is above the siltstone. This is significant even if neither chocolate claystone nor polymictic conglomerate can be found, as, in the Hawkesbury Sandstone, siltstone rarely exceeds 10 feet in thickness and only very rarely exceeds 20 feet in thickness in the area mapped. Current Bedding :—The current bedding of the Hawkesbury Sandstone almost invariably dips to the NE and only rarely varies more than to the north or ENE. In the Narrabeen Group it dips to the ESE or S. The uppermost sandstone in the Putty district dips east but is overlain by chocolate claystone. Outcrop :—In general, poor outcrop is found on slopes facing S or SW because of the lush vegetation and deep soil developed. This is probably because of the increased moisture and humidity in such protected areas. N and NW facing slopes are often bare or only covered with light brush and sparse soil cover. Thus they are more rewarding when examined in the field. Correlation and Comments Tigures 2 and 3 show two east-west cross sections and one north-south. The correlation between 1 and 7 shows how the Burralow Formation can, with some difficulty, be followed along a north-south line west of the Lapstone Monocline. Difficulties were experienced in correlating sections, where insufficient of the Grose Sandstone was exposed to be sure that. the sandstone at the base of a section was not another interbed in the Burralow Formation. Section 7 and the Mount Murwin well confirm the validity of the Burralow Formation and Grose Sandstone divisions of the Narrabeen Group. In particular, Sections 6 and 7 cannot be correlated except on the possibility of the Grose Sandstone occurring at the base of Section €, as shown in Figure 3. STRATIGRAPHY OF PUTTY-UPPER COLO AREA, SYDNEY BASIN In spite of the difficulty in correlating these sections, it is doubted that Section 7, as shown on the cross section, is far from its correct position relative to the other sections. This is supported by Section 5 in which the thickness of the Burralow Formation is 405 feet. The underlying sandstone is known to be within the Grose Sandstone as the thickness of the sandstone unit increases to about 250 feet about two miles further up Wollemi Creek. Section 8, some three to four miles west of Section 5 and shown following Section 7 is included to demon- strate the “sanding up” of the Burralow Formation westwards. Difficulty is experienced in recognising the Grose Sandstone-Burralow Formation boundary eastwards from the Lapstone Monocline. This is shown by the east-west section from Section 7 to Sections 9 and 10 thence east to Section 11. From these sections it appears that alternating sandstone-siltstone lithologies persist for at least the uppermost 500 feet of the Narrabeen Group. From the air photo interpretation between 33°00’S and 33°15’S, the Narrabeen Group throughout the Macdonald River system is seen to have produced a stepped relief on hillsides, indicative of alternating sandstone- siltstone lithologies. Over 800 feet of the Group is exposed along the Macdonald River at about 33°07'S. This indicates that the Grose Sand- stone has become a sequence of interbedded sandstone and siltstone and as such would be indistinguishable from the Burralow Formation as seen west of the Webbs Creek-Mount Murwin anticline. Alternatively, the Burralow Forma- tion could have thickened. Between 12 and 13 the uniformity of the basal, probable Caley Formation, over this distance is in striking contrast to the problem in attempting to follow the Burralow Formation eastwards from Sections 4 to 14 and then on to 19. Some 12 sections were originally measured between 14 and 19 and it was most problematical correlating individual units between each section. Chocolate claystone and siltstone, regarded as the most reliable horizons for correlation elsewhere in the basin, were found to be useless for this purpose within the area studied. They were not confined to readily correlated horizons as are the Bald Hill Claystone and Stanwell Park Claystone of the South Coast (Hanlon, Osborne and Raggatt, 1953), but occurred haphazardly throughout the entire stratigraphic section. 31 Basic Igneous Bodies GENERAL There are a number of occurrences of basic volcanics throughout the area, some being caps, representing flow remnants, others being volcanic necks. The term basalt is used, but in a wide sense to cover all dark fine grained basic volcanic rocks. The basalt is almost invariably fine grained, very dark blue to black in colour, and lacks phenocrysts of any kind. No form of metamorphism, either as baking due to heat or fracturing of the sur- rounding sediments, was found associated with the necks or caps. NECKS The necks are more common west and north of the axes of the Mellong Syncline-Howes Valley Syncline. The number and size of these bodies increases towards the edge of the basin as 1s evident by the number and distribution recorded by Carne (1908) and Day (1961). Their position commonly coincides with the area from which the Hawkesbury Sandstone is absent. Between 33°00’S and 33°15’S, necks are absent within the area mapped, except for those west of the Mellong Syncline, but are scattered over the area south of 33°15’S. The necks invariably weather faster than the surrounding sediments and are thus always found in depressions. Often no outcrops or even floaters were found, but when they were, the rocks in them were commonly found to be breccias with fragments of sediments, especially water worn pebbles. One exception is the large neck at (38807720) where a central body of large blocks of columnar basalt occurs. This is surrounded by a wide rim of dark brown soil, probably derived from surrounding breccia. Even when no outcrop can be found, the presence of cleared lush grassland and the occurrence of a dark brown rich loam which never occurs on the Triassic sandstone country, is a very good indication of the presence of basic volcanics. One neck where brecciation occurs is at Clear Farm Hollow (36939298), and is revealed by a number of recent cuttings at the side of the Putty Road. Brecciation and inclusion of pieces of country rock including sediment and water worn pebbles, the latter being common in the conglomerate beds of the Narrabeen Group and Singleton Coal Measures, the sus- ceptibility of the breccia to weathering and its extreme softness are all evident at this locality. MALCOLM C. GALLOWAY ) we \ Nog rnontins mourant Sa ) Hf / See, TOUACONG eanoe a NS. Van 3 > “S==@ WINDSOR 4 Se See REFERENCE Anticline Track <~}+— Syncline —=>_ -. Track, very poor 4whee/ drive = Monochne Spot Height trigs. OD) beological reliability ' sub-areas aa Locality ofsection Locality of section which 's off mepin direction shown. Section lines SCALE a ag i Waa yi \JA0G EXOIL KURRAJONG ¥ HEIGHTS No.1 SS ee MILES Fic. 2,—Major structures, section lines and localities, ew ween | / AOQUNTJAIN \T. MURWIN No.1 STRATIGRAPHY OF P } Kurrajong Heights FORMATION = AN ec N S send = | [4 | ac > = | uw =a =) | — | n | Q | =z x { W } Kurrajong Heights SANDSTONE GROSE | FORMATION Fic. 3.—Localities and section FORMATION BURRALOW SANDSTONE SANDSTONE FORMATION STRATIGRAPHY OF PUTTY-UPPER COLO AREA, SYDNEY BASIN 33 URRALOW FORMATION S a SANDSTONE SANDSTONE GROSE Fic. 3.—Localities and section lines are shown on Fig. 2. GROU UNDIFFERENTIATED NARRABEEN FIG.3 LOCALITIES AND SECTION LINES ARE SHOWN ON FIGURE 2 NUMBERS ABOVE SECTIONS REFER TO FIELD LOCALITIES [ SHALE ==) [SirstoNe >=] eer LAY: ICLAYSTONE LEGEND Numbers above sections refer to field localities. Ag ne cM Ss I MouNT TAs Suny os \ ode SS Ves CAINOZOIC POST TRIASSIC TRIASSIC LEGEND [Qa] Alurivm. Shomn only where extensive Unnamed necks and caps | Tb | 4ese/s, Yolcante Breccias Wianamatta Group Shales and Flaggy sandstones 99) Hawkesbury Sandstone Sendstones,rere shales Narrabeen Group Burralow Formation Shele, chocolete oleystone, Flaggy sendsfone, sandstone Grose Sandstone [Rng | pee eta sey Undifferentiated Shales jes pasiene : —+ st + Anticline , syactine, monecline 2! ‘ To. ° a ~ FE AVMOTIVS ‘0D WIODTVN a MALCOLM C. GALLOWAY 34 "yorTystp A}yNg-0fOD 9y} Jo ABdo[oOen—'F “O17 saliW Ol g 0 000'0S2:! 31VIS eusjoovew ‘auij2uUhs € auyolfuy oe -——t— —l— sayhkP aJ!SSQf —~—e—e— - guoyskej2 246/220Y0 P daaenee “a/eYyS oe payeijuatays pup) auogshb/2 348/004 9504 ‘ geys 2404‘ WUA{SPUBS | Buy | auojspueg 98019 elas pues. 'auasspues Kb6e/4 an 9 ] SsSV WL ‘avopsheyo 248/02049 ' 9/2Y¢ au | ae Times sayeys 018s‘ sauvapspues Lu | quoyspues Kunqsaymey savojspues Kbbeyy pue s2/es | | dnolg eyJeWeuelA Sel2Iadg DUCHY ‘gyjeseg | a sde9 pue syseu paweuu/) JISSVIML 1S0d arisuayrea asaym Ajuo uMoys “WNIAN|[Y | ed | DIOZONIVD QN39431 Mow& a ss. cr ¢@ €—=—IN fo) a CAPS _ These invariably occur on or near the crests of hills with large angular blocks of basalt always evident. Kare polygonal blocks suggest that, in the fresh basalt, columnar jointing was common. The caps are generally restricted to the west and north of the area, probably ‘representing remnants of once more extensive flows. There is little reason to suppose that they are denuded intrusions, as nowhere are sediments found overlying them. None are known to occur in the area south of 33°15'S. The occurrences west of Six Brothers trig are the only ones known between latitudes 33°00’S and 33°15'S. A number of basalt caps also occur north of 33°00’S. Generally their bases are obscured by scree making it difficult to estimate the relief of their bases. Two exceptions are :— (a) The occurrences west of Six Brothers trig (85658964) appear to have been laid down on an irregular surface. This is revealed by the more western of the two bodies where basalt occurs along a spur leading down from a knob of sandstone some 30 feet higher than the base of the basalt, which it also partially surrounds. (b) The Mount Wirraba basalt (35158165) also appears to be laid down on an irregular surface, as its base is by no means flat. The hill is not all capped by basalt ; between the two occur- -rences is a knob of sandstone which is higher than the more western body. Dykes | ! | Possible dykes occur between 33°05’S and | 88°15" S (see Fig. 4). Wide fissures with sheer walls, about 50 to 70 feet wide and several ! miles long, cleave through the continuous outcrop of the Hawkesbury Sandstone. Throughout the clefts only floaters of sandstone occur. Considering the paucity of outcrop in the necks, a dyke of this thickness would be expected to be so extensively weathered that it would not outcrop. These fissures could be faults in which shearing had so brecciated the sandstone that it fell to powder on exposure and so did not outcrop. If this were the case, why did shearing stop completely at the two sandstones which border the zone of no outcrop which exists to-day ? One would expect joints, minor faulting, or shearing to be evident in the sandstone at either side, or at least to cause an irregular weathering surface on the sand- stone. Instead, two almost planar vertical walls occur. STRATIGRAPHY OF PUTTY—UPPER COLO AREA, SYDNEY BASIN 35 Another dyke occurs on Mogo Hill (40839025) in the road cutting near the base of the Hawkes- bury Sandstone. It is about one foot wide and completely kaolinised. Other dykes in a similar state occur around Howes Valley, but are only exposed in road cuttings. Narrow fissures with vertical walls occur in the sandstone at scattered localities along Wollemi Creek; these may represent the sites of now completely weathered out dykes. Peneplanation and its Relation to Bases of Caps Comparing the altitude of the base of the basalt flows on the various caps, it is seen that Mount Yengo, Poppong, Wareng and Warrawolong (42729157) all have the bases of their basalt caps at roughly the same level of 1800 feet. The Culoul Range caps further south are at 1900 feet, while due north Kindarun Mountain, west of Mount Wareng, has its basalt base at 2200 to 2300 feet ; Mount Wirraba, west of Kindarun, has its basalt base at 2400 feet ; Gospers Mountain further west has its basalt base at 2600 feet. It can be seen that these levels coincide with a surface which becomes progressively higher westwards and is higher than that of the supposed Tertiary peneplain. The Tertiary peneplain is supposed to be represented by a surface joining the highest points of the topo- graphy. The higher basalt surface is clearly above this and possibly corresponds to an earlier stage in the development of the peneplain. The additional caps, such as Box Bump (34038306), Green Hill (37298396) and Putty trig (36388305) are smaller in extent and at a much lower level, possibly representing a later stage when dissection of the Tertiary peneplain was occurring. The Putty trig basalt, in particular, is well below the surface of the other basalts and may represent an even later phase in vulcanism, following erosion of the “higher ’”’ basalts and of the Tertiary peneplain surface. Age The age of these bodies has generally been regarded as Tertiary. Recent work on the age of the Prospect intrusion, based on radioactive dating and supplemented by paleomagnetic work (Manwaring, 1963), has established it as Middle Jurassic. Paleomagnetic work on the Peats Ridge neck indicates a probable Tertiary age (Manwaring, 1963). 36 MALCOLM C. Acknowledgements This work was undertaken whilst working for Australian Oil and Gas Corporation of Sydney and completed as part of the work toward an M.Sc., degree at the University of Sydney. I would like to thank the company for allowing me to use in this paper the results of the work carried out whilst working for them. In particular I would like to thank Mr. J. Stuntz who, as Chief Geologist, organised the company work so that I was able to continue working in the same district virtually without interruption. Discussions with Mr. J. Stuntz throughout the field work and with Mr. K. Bradley of A.O.G., in the later stages of the field work helped to mould the ideas leading to this work. Discussions also took place from time to time with various members of the staff of the Uni- versity of Sydney, particularly Dr. A. J. T. Wright and my supervisor Dr. T. B. H. Jenkins. Criticism of the manuscript at various stages by Drs. T. B. H. Jenkins, K. A. W. Crook and C. T. McElroy were of considerable assistance. Finally I would like to thank my mother for her encouragement throughout this study and for typing the whole of this paper. Geological Reliability The geological reliability of the sub areas shown on Fig. 2 is as follows: Area 1.—The whole of this area has been mapped in the field by the author, except the extreme west and north west between latitudes 34°45’S and 33°00’S. Reconnaissance work was carried out to ensure that only Narrabeen Group sediments occurred throughout this area. Area 2.—No field work has been done in this area. With the guidance of field work to the south and west the boundaries have been determined by air photo interpretation. The geology of these areas has been reduced from maps at a scale of 1: 63360 and1: 50,000. Thus, the boundaries shown on Fig. 4 are regarded as very reliable. Area 3.—The air photos being used did not cover this area and no field work was carried out. The boundaries shown were extrapolated from the north, west and south of the area. However, on the scale of Fig. 4 the boundaries are thought to be reliable. GALLOWAY Bibliography Unpublished operations subsidised under the Petroleurn Search Subsidy Acts are marked *; they are available for study at the Bureau of Mineral Resources in Canberra, and at the Department of Mines, Sydney. Unpublished University theses are available for study at the University libraries. BookeErR, F. W., 1957. Studies in Permian Sedimenta- tion in the Sydney Basin. Tect. Rept. Dept. Mines, N.S.W., 5, 10-62. CARNE, J. E., 1908. Geology and mineral Resources of the Western Coalfield. Mem. Geol. Surv. N.S.W., Geol. Series No. 6. Crook, K. A. W., 1956(a): Kurrajong-Grose River District. Thesis, Univ. of Syd. Crook, K. A. W., 1956(b). The stratigraphy and petrology of the Narrabeen Group in the Grose River District. J. Proc: Hoy igsoc., N- S: Vie 90, 61-79. Day, J. A. F., 1961. Geology of the Rylstone Uppeg Goulburn River District. Unpub. Ph. D. thesis, Univ. of Syd. ENGEL, B. A., 1962. Geology of the Bulahdelah- Port Stephens district, N.'S.W. J. Proc. Row Soc. N.S.W., 95, 197-215. GaLLtoway, M. C., 1965. The Geology of an area covered by the St. Albans, Mellong and Mount Yengo One Inch Series maps. Unpub. M. S@ thesis, Univ. of Syd. GatLoway, M. C., 1967. Heavy mineral and palaeo- current studies, Hawkesbury Sandstone and Narrabeen Group (Triassic), Sydney Basin, N.S.W. In preparation. Hamtinec, D. D., and McKEtLrar, M. G., 1963. East Maitland No. 1 well completion report unpubl.* Han.on, F. N., OSBORNE, G. D., and Raccatt, H. G,, 1953. Narrabeen Group: Its subdivisions between the South Coast and Narrabeen-Wyong District. J. Proc. Roy. Soc. N.S.W., 87, 106-120. LovERING, J., 1954. The stratigraphy of the Wiana- matta Group. Aus. Mus. Rec., 23, 4, 169-210. McEtroy, C. T., 1962. Sydney, N.S.W., 1: 250,000 Series. Bur. Min. Resour. Aust. explan. Notes, 1, 56-5. McGarry, D. J., and Rosz, D. M., Geology of the Putty-Wisemans Ferry Area. Unpub. A.0.G. veport No. 112. MANWARING, E. A., 1963. The Palaeomagnetism of some igneous rocks of the Sydney Basin. J. Proc. Roy. Soc. N.S.W., 96, 141-151. OsBoRNE, G. D., 1948. A review of sorne aspects of the stratigraphy, structure, and physiography of the Sydney. Basin. Proc. Lin, SocNes. Ve 73, IV-XXXVII. OsBoRNE, G. D., 1950. The Geology of the Unpub. M. Se. The structural evolution of the Hunter-Manning Myall Province, N.S.W., Roy: Soc. N.S.W.,\ Monoge wll PERRY, R. G., and Stuntz, J., 1963. A.O.G. Loder No. 1, Sydney Basin, N.S.W. Unpub.* RaGGatt, H. G., 1938. Evolution of the Perrmo- Triassic Basin of East Central N.S.W. Unpub. D. Sc. Thesis, Univ of, tsya- StuNTz, J., 1965. Petroleurn exploration in the Sydney Basin. A.P.E.A. Jour., 59-62. STUNTZ, J., PERRY, R. G., and Wess, E. A., 1963. Well completion report, Kurrajong Heights No. 1, unpub.* STUNTz, J., and WriGurT, A. J., 1963. Mount Murwin No. 1 bore, Sydney Basin, N.S.W., well com- pletion report. Unpub.* Report of the Council for the Presented at the Annual and General Monthly Meeting of the Society held 5th April, 1967, in accor- dance with Rule XXVI. At the end of the period under review the composi- tion of the membership was 352 members, 21 associate thembers and 8 honorary members ; 17 new members were elected. Four members and two associate mem- bers resigned; the names of three members were removed from the list of members in accordance with Rule XVIII. It is with extrerne regret that we announce the Joss by death of : Sir Neil Hamilton Fairley (elected to Honorary Membership, 1952), Thelma I. Christie (elected 1953), Edward J. Kenny (elected 1924), Stephen L. Leach (elected 1936), Henry J. Meldrum (elected 1912), Archibald B. B. Ranclaud (elected 1919), Arthur Spencer Watts (elected 1919). Centenary. To cornmemorate the 100th Anniversary of the Grant of Royal Charter by H.M. Queen Victoria, the following celebrations were held : Sth, June: Ihe Centenary Dinner under the Patronage of His Excellency the Governor of New South Wales, Sir Roden Cutler, V.C., K.C.M.G., O.B.E., in the Sapphire Room, Australia Hotel, the attendance being 85 (see ‘‘ Journal and Pro- ceedings ”’, vol. 100, pp. 1-8). 28th October: The Centenary Address entitled ‘1866, the Challenge to Science; 1966, the Challenge of Science’’, was held in the Hall of Science House, and was delivered by Professor pee Pikin, (CMG. M.A., Ph.D. The Address was preceded by a Buffet Meal held in the Edge- worth David Room. Ist November to 18th December : The Centenary Exhibition was held in the Australian Museum, College Street, Sydney. Exhibits were contributed by Sydney Observatory; Institute of Medical Research, Royal North Shore Hospital; National Standards Laboratory ; Australian Atomic Energy Commission and the Museum of Applied Arts and Sciences. Several cases contained exhibits in connection with the work of K. E. Bullen, T. W. E. David, L. Hargrave, A. Liversidge, J. H. Maiden, H. G. Smith; all distinguished members of the Society. Also, an exhibit emphasizing the range of material in the Society’s library and in the “ Journal and Proceedings ”’ was displayed. Eight monthly meetings were held. The abstracts of all addresses have been printed on the notice paper. The proceedings of these will appear later in the issue of the “ Journal and Proceedings ’’. The members of the Council wish to express their sincere thanks and appreciation to the eight speakers who contributed to the success of these meetings, the average attendance being 45. The Annual Social Function was held on 30th March at the Sydney University Staff Club and was attended by 55 members and guests. C Year Ended 31st March, 1967 The Council has approved the following awards : The Clarke Medal for 1967 to Professor S. Smith- White, D.Sc.Agr., F.A.A., School of Biological Sciences, University of Sydney. The Society’s Medal for 1966 to Mr. H. A. J. Donegan, of the Mining Museum, Sydney. The James Cook Medal for 1966 to Sir William Hudson, K.B.E., F.R.S., of the Snowy Mountains Hydro Electric Authority, Cooma. The Edgeworth David Medal for 1966 to Dr. R. I. Tanner, Department of Engineering, Brown University, Providence, U.S.A. The Archibald D. Ollé Prize to Dr. R. A. Binns, Department of Geology, The University of New England. The Liversidge Research Lecture for 1966, entitled “Organic Metals ?’’, was delivered by Professor L. E. Lyons, Ph.D., Department of Physical Chemistry, University of Queensland, on 12th July (see “‘ Journal and Proceedings ’’, vol. 101, pp. 1-9). The Society has again received a grant from the Governinent of New South Wales, the amount being $1,500. The Government’s interest in the work of the Society is much appreciated. The Society’s financial statement shows a deficit of $2,133.11. The New England Branch of the Society met 3 times during the year and the Proceedings of the Branch follow this report. The President represented the Society at the Com- memoration of the Landing of Captain James Cook at Kurnell ; attended the Garden Party held at Govern- ment House in Honour of the Birthday of Her Majesty the Queen; the State Reception in the Art Gallery of New South Wales held to welcome the President of the U.S.A. and Mrs Johnson ; and, during the visit of His Royal Highness the Duke of Edinburgh, was a guest at a State Luncheon; and was present at the Australian Function on the occasion of the official opening of the South East Asia Commonwealth Cable by Her Majesty the Queen. The President attended the Annual Meeting of the Board of Visitors of the Sydney Observatory. We congratulate Professor A. P. Elkin, on the award of the C.M.G.; Dr. H. J. Hynes, on the award of a Fellowship of the Australian Institute of Agricultural Science ; Mr. J. M. Rayner, on the award of the O.B.E.; and Dr. Alice Whitley, on the award of the M.B.E. The Society’s representatives on Science House Management Committee were Mr. H. F. Conaghan and Mr. W. H. G. Poggendorff. Publications. Two parts of volume 98, volume 99 which was the W. R. Browne volume and volume 100, part 1, have been published during the year. The Centenary Volume, which will be a special publica- tion, is planned for the coming year. Council held 11 ordinary meetings and the attendance was as follows: Prof. A. H. Voisey 11; Dr. A. A. Day 7; Prof; R. J. W. Le Fevre 6; Mr. H. H. G. McKern 10; Mr. W. H. G. Poggendorff 4; Mr. J. L. Griffith 38 REPORT OF THE COUNCIL FOR THE YEAR ENDED 31st MARCH, 1967 10; Dr. A. Reichel 8; Mr. H. F. Conaghan 9; Mr. Ri Aw Bure 65 “Mr ja ©. Cameron.) ye Mins AN Harper 6; Prof. A. Keane 3 (absent-on-leave 3) ; Mri.) Katamura 02 Mis: Ms Kryskosy. “nyse (appointed 30/8/1966) 3; Dr. D. B. Lindsay (New England Branch representative as from November, 1966)0'5 Mr: J. W. G:; Neuhaus 8 > Mr: }. 2 Pollard 130 Me, W. H. Robertson 6; A/Prof. kK) LL. Stanton (absent-on-leave 8 and not eligible for the remainder of the session as the New England Branch had nomi- nated Dr. D. B. Lindsay as its representative commen- cing the current session of the Branch). Council has prepared a new set of Rules and By-laws for presentation to the members of the Society. The Libravy—Periodicals were received by exchange from 390 societies and institutions. The amount of $386.33 was expended on the purchase of 11 periodicals and book-binding. This expense was partly defrayed by an amount of $190.00 realized from Company Mem- bership subscriptions. Repairs to and binding of the more rare sets of periodicals continues, costing $242.09 during the last year. Among the institutions which made use of the library through the inter-library loan scheme were : N.S.W. Govt. Depts.—Dept. of Agriculture, Hawkes- bury Agricultural College, Electricity Commission of N.S.W., Forestry Commission, Dept. of Mines, National Herbarium, Dept. of Public Health, Railway Dept., Soil Conservation, Water Conservation & Irrigation Commission, Division of Wood Technology. Commonwealth Govt. Depts——Australian Atomic Energy Commission, Bureau of Mineral Resources, Geology & Geophysics, C.S.I.R.O. Divisions : Armidale Pastoral Research Station; Canberra Laboratories ; Animal Physiology, Prospect; Chemical Research Laboratories, Melbourne; Coal Research, Ryde; Fisheries and Oceanography, Cronulla; National Standards Laboratory, Sydney; Textile Physics, Ryde; Wildlife, Canberra. Universities and Colleges—Adelaide University, Aust- ralian National University, Sydney University, Canter- bury, N.Z. University, Flinders University of South Australia, Melbourne University, Monash University, Mt. Stromlo Observatory, New England University, University of New South Wales, Queensland University, School of Public Health and Tropical Medicine, Univer- sity of Tasmania, University College of Townsville, University of Western Australia, Wollongong Univer- sity College. Companies—Australian Cream of Tartar Ltd., A.W.A. Ltd., Australian Iron and Steel Co. Ltd., Australian Glass Manufacturers Ltd., B.H.P. Co. Ltd., Commonwealth Industrial Gases, C.S.R. Co. Ltd. Head Office, James Hardie & Co) Eman eis Lids Lysaght Ltd., McDonald Constructions, Sulphide Corp. Pty. Ltd., S.T.C. Ltd., Unilever, Union Carbide Ltd: Research Institutes—Bread Research Institute, C.S.R. Research Laboratories, Government Chemical Labora- tories, Royal North Shore Hospital, St. Vincent’s Hospital, Sydney Hospital. Museum—Australian Museum. Miscellaneous—Dept. of Agriculture, Stock and Fisheries, Papua; Institution of Engineers, Aust.; Linnean Society of N.S.W.; Newcastle City Council ; Dept. of Primary Industries, Brisbane; W.E.A., Sydney. Our Assistant Secretary, Miss M. Ogle, retired on 3lst December, 1966 after a period of 20 years with the Society. The Council wishes to express its apprecia- tion of her excellent and untiring services during this record period. Miss Ogle will be continuing for some time on a part time basis. J. L. GRIFFITH, Honorary Secretary. 5th April, 1967. | Abstract of Proceedings 6th April, 1966 The ninety-ninth Annual and eight hundred and ninth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Dr. Alan A. Day, was in the chair. There were present 55 tnembers and friends. Donald Westland Emerson was elected a member of the Society. The Annual Report of the Council and the Financial Staternent were presented and adopted. The following awards of the Society were announced : The Society’s Medal for 1965: Dr. Francis Lions. The Clarke Medal for 1966: Prof. Dorothy Hill, Beko. PAA. The Walter Burfitt Prize for 1965: Fleming, O.B.E. The Jarnes Cook Medal for 1965: Gunther, C.M.G., O.B.E. The Edgeworth David Medal for 1965: L. Dillon. Dr. W. R. Browne was presented with a specially bound copy of Volume 99 of the ‘‘ Journal and Pro- ceedings ’’, published as a tribute to Dr. Browne’s long and distinguished service to Australian science. Office-Bearers for 1966-67 were elected as follows : Eresident ;: A. H.-Voisey, D.Sc. Vice-Presidents: A. A. Day, Ph.D., R. J. W. Le Fevre, D.Sc., F.R.S., F.A.A., H. H. G. McKern, M.Sc., W. H. G. Poggendorff, B.Sc. Agr. Hon. Secretaries: J. L. Griffith, B.A., M.Sc., A. Reichel, Ph.D. j Hon. Treasurer: H. F. Conaghan, M.Sc. Blemnbers of Council: R. A. Burg, A.S.T.C., J. C. Cameron, M.A., B.Sc., D.I.C., A. F. A. Harper, M.Sc., A. Keane, Ph.D., T. E. Kitamura, B.A., B.Sc.Agr., J. Middlehurst, M.Sc., J. W. G. Neu- haus, A.S.T.C., J. P. Pollard, Dip.App.Chem., W.H. Robertson, B.Sc., R. L. Stanton, Ph.D. Messrs. Horley & Horley were re-elected auditors to the Society for 1966-67. The retiring President, Dr. Alan A. Day, delivered his Presidential Address entitled ‘‘ A Historical Outline of the Development of Geophysics in Australia ’’. The following papers were read by title only : “ Petrography of some Permian Sediments from the Lower Hunter Valley of New South Wales’”’, by J. D. Hamilton. “The Big Hole near Braidwood, N.S.W.’’, by J. N. Dr. Charles A, Dre johnei: Prof. John Jennings. “ On Lepidipteris Madagascariensis Carpentier (Pelta- ‘spermaceae) ’’, by John A. Townrow. “Precise Observations of Minor Planets at Sydney Observatory during 1963 and 1964’’, by W. H. Robert- son. At the conclusion of the Presidential Address the | retiring President welcomed Professor Voisey to the Presidential Chair. 4th May, 1966 The eight hundred and tenth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Professor A. H. Voisey, was in the chair. There were present 44 members and visitors. The following were elected members of the Society : Norman Thomas Feather, Petro Majstrenko and John Herbert Rattigan. An address entitled ‘‘ Oral Contraceptives from the Medical Viewpoint ’’ was delivered by Professor H. M. Carey, of the School of Obstetrics and Gynaecology, University of New South Wales. It was announced that as the Centenary Dinner was being held on 8th June, there would be no General Monthly Meeting held during that month. No meeting was held during the month of June, 1966. 6th July, 1966 The eight hundred and eleventh General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Professor A. H. Voisey, was in the chair. There were present 32 members and visitors. The following were elected members of the Society : Roger John Henderson and Derek Barber Lindsay. The following papers were read by title only: ‘‘ Plant Microfossils from a Shale within the Wollar Sandstone, N.S.W.”’, by R. J. Helby; ‘‘ Time Spent by Neutrons inside a Narrow Resonance’’, by C. A. Wilkins; ““Minor Planets Observed at Sydney Observatory During 1965’, by W. H. Robertson. An address entitled “‘ World Wide Water Problems ’’, was delivered by Mr. R. J. Griffin, of the Hydrology Division, Geological Survey, Department of Mines, N.S.W. 3rd August, 1966 The eight hundred and twelfth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Professor A. H. Voisey, was in the chair. There were present 25 members and visitors. Robin James Helby was elected a member of the Society. An address entitled ‘‘ Physics, Chemistry and Biology of Some Long Molecules ’’ was delivered by Professor P. Mason, School of Mathematics and Physics, Macquarie University. 7th September, 1966 The eight hundred and thirteenth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Professor A. H. Voisey, was in the chair. There were present 64 members and visitors. 40 ABSTRACT OF PROCEEDINGS, 1966 The following were elected members of the Society : Barry Deane Webby and Helmut Wopfner. Films: ‘‘ The Dead Sea Scrolls’ and ‘“‘ The Hebrew University ’’ were screened by courtesy of the New South Wales Friends of the Hebrew University and were introduced by Mr. A. D. Crown, President of the New South Wales Friends of the Hebrew University and Lecturer in Semitic Studies at the University of Sydney. 5th October, 1966 The eight hundred and fourteenth General Monthly Meeting was held in the Hall of Science House, Sydney, at 7.45 p.m. The President, Professor A. H. Voisey, was in the chair. There were present 25 members and visitors. The following were elected members of the Society : Ian Douglas Blayden, Neil Neville Gow, Krishna Kumar Sappal and Stirling Edward Shaw. The following papers were read by title only: “ The Gravity Terms in the Water Entry Problem ’’, by A. H. Low ; ‘“‘ Occultations Observed at Sydney Observatory During 1964-65 ”’, by K. P. Sims. An address entitled “‘ What is the Quality of a Musical Note ?”’ was delivered by Mr. R. S$. Caddy, Vice- Chancellor’s Division, the University of New South Wales. 2nd November, 1966 The eight hundred and fifteenth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Professor A. H. Voisey, was in the chair. There were present 87 members and visitors. The following were elected members of the Society : Charles Phillip Gabel, George Studley Gibbons and Geoffrey Harold Roper. The following paper was read by title only: ‘“‘ The Balickera Section of the Carboniferous Kuttung Facies, New South Wales ’’, by J. H. Rattigan. An address entitled ‘‘ Offshore Exploration ’’ was delivered by Mr. D. C. Edwards, of ESSO Exploration Australia, Inc., Sydney. 7th December, 1966 The eight hundred and sixteenth General Monthly Meeting was held in the Hall of Science House, Sydney, at 7.45 p.m. The President, Professor A. H. Voisey, was in the chair. There were present 30 members and visitors. George Arthur Peterson was elected a member of the Society. An address entitled ‘“‘ A Pattern for a University in New Guinea ”’ was delivered by Dr. John T. Gunther, C.M.G., O.B.E., Vice-Chancellor, University of Papua and New Guinea, Port Moresby. Members of the Society, April, 1967 A list of the members of the Society up to Ist April, 1966 is included in Volume 100. During the year ended 31st March, 1967 the following were elected to membership of the Society : BLAYDEN, Ian Douglas, B.Sc.(Hons.), Geologist, 13 Murrakin Street, Kahibah, N.S.W. Emerson, Donald Westland, M.Sc., B.E.(App.Geol.), Department of Geology and Geophysics, The Uni- versity of Sydney. FEATHER, Norman Thomas, B.A., M.A., Ph.D., Dip.Ed., Associate Professor of Psychology, The University of New England. GABEL, Charles Phillip, Forester, 59 Abingdon Road, Roseville. GIBBONS, George Studley, M.Sc., 75 Nicholson Street, St. Leonards. Gow, Neil Neville, B.Sc.(Hons.), C.R.A. Exploration, G.P.O. Box 384D, Melbourne. HeELBy, Robin James, M.Sc., 344 Malton Road, North Epping. HENDERSON, Roger John, B.Sc.(Hons.), Department of Geology and Geophysics, The University of Sydney. eoNDSAY, Derek Barber, B.Sc., M.A., D.Phil.(Oxford), Department of Biochemistry and Nutrition, The University of New England, Armidale. MAJSTRENKO, Petro, M.Sc.(Copenhagen), Lecturer in Mathematics, The University of New England, Armidale. PETERSON, George Arthur, B.Sc., B.E., 55 Roseville Avenue, Roseville. Financial The Honorary Treasurer’s Report The Society this year recorded a deficit of $2,133.11. The major factors contributing to this deficit were a loss of $462.27 on the Centenary Celebrations, increases in expenditure of $172.00 for library purchases, $104.00 for postages, $845.00 for printing and $517.00 for salaries together with an overall decrease of $159.00 in income. In addition to the subscriptions to journals and periodicals being increased, a number of rare and valuable books belonging to the Society were repaired resulting in an increase in the library purchase expendi- ture. The increased expenditure on printing was due to the increased activity in publication. Volume 98, parts 3 and 4, Volume 99 and Volume 100, part 1, of the Society’s ‘“‘ Journal and Proceedings’? were pub- lished during the year. RATTIGAN, John Herbert, Ph.D., M.Sc., 17 Mills Street, Warners Bay, N.S.W. Roper, Geoffrey Harold, Ph.D., M.Sc., Associate Professor of Chemical Engineering, The University of New South Wales, Kensington. SAPPAL, Krishna Kumar, M.Sc., Geologist, Department of Geology, Nagpur University, Nagpur, India. SHAW, Stirling Edward, B.Sc.(Hons.), Ph.D., F.G.A.A., School of Earth Sciences, Macquarie University, Eastwood. WEBBY, Barry Deane, Ph.D., M.Sc., Department of Geology and Geophysics, The University of Sydney. WoPFNER, Helmut, Ph.D., Supervising Geologist, South Australian Geological Survey, S.A. Depart- ment of Mines, Box 38, Rundle Street, P.O., Adelaide, S.A. During the same period resignations were received from the following : Burns, (Mrs.) Susan Mary (Associate). Findler, Nicholas Victor. Gow, Neil Neville (resigned as an associate to transfer to full mermbership). Jones, (Mrs.) Robin. Murray, Patrick Desmond Fitzgerald. Wilson, Peter Robert. and the folowing names were removed from the list of members under Rule XVIII: Hawkins, Cedric Arthur. Lang, Thomas Arthur. Lewis, Philip Ronald. Statement The expenditure on salaries as shown in the balance sheet includes an amount of $604.89 for long service leave payment. Company membership subscriptions amounting to $190.00 are not shown as income but are credited to library purchases, for which these subscriptions are intended. An application to the Minister for Education and Science for an increase in the Government Grant to the Society was refused but a grant of $4,000.00 towards the cost of producing the Centenary publication was approved. H. F. CoNAGHAN, Honorary Treasurer. 5th April, 1967. 42 1966 $ 384 36 153 8,570 60,030 6,376 502 $76,051 4,218 1,755 24 2 $76,051 ANNUAL REPORTS THE ROYAL SOCIETY OF NEW SOUTH WALES BALANCE SHEET AS AT 28th FEBRUARY, 1967 LIABILITIES Accrued Expenses Subscriptions Paid in Advance Life Members’ Subscriptions—Amount carried forward. Trust Funds (detailed ela Clarke Memorial Walter Burfitt Prize Liversidge Bequest Ollé Bequest Accumulated Funds Library Reserve Account .. Employees’ Long Service Leave Fund Provision. Contingent Liability (in connection with Perpetual Lease) ASSETS Cash at Bank and in Hand Investments— Commonwealth Bonds and Inscribed Stock— At Face Value—held for: Clarke Memorial Fund ‘ Walter Burfitt Prize Fund Liversidge Bequest .. ; General Purposes Fixed Deposit—Long Service Leave Fund Debtors for Subscriptions .. ss Less: Reserve for Bad Debts Science House—One-third Capital Cost Library—At Valuation ; Library Investment—Special Bonds Furniture and Office Depreciation Pictures—At Cost, Jess Depreciation Lantern—At Cost, less Depreciation Equipment—At Cost, less 4,270.32 2,426.43 1,425.04 581.26 3,600.00 2,000.00 1,400.00 9,680.00 132.85 132.85 8,703.05 57,870.28 7,520.02 $74,325.45 1,764.76 16,680.00 518.40 30,470.43 13,600.00 9,600.00 1,667.06 22.80 2.00 $74,325.45 ANNUAL REPORTS TRUST FUNDS Walter Clarke Burfitt Liversidge Ollé Memorial Prize Bequest Bequest ; $ $ $ $ Capital at 28th February, 1967 3,600.00 2,000.00 1,400.00 — Revenue— Balance at 10th ees 1966 546.01 471.52 56.33 496.76 Income for Period 190.56 105.71 74.71 84.50 736.57 577.23 131.04 581.26 Hess. sexpenditure 66.25 150.80 106.00 = Balance at 28th February, 1967 $670.32 $426.43 $25.04 $581.26 ACCUMULATED FUNDS 4 3 Balance at 10th February, 1966 60,029.63 Add— Transfer Salary Adjustment 0.10 Reserve for Bad Debts 117.05 , ——_—— 60,146.78 essa: Transfer Salary Adjustment ye 0.10 Transfer for Long Service Leave Fund.. 86.59 Subscriptions Written Off 56.70 Deficit for the Period 2,133.11 oe 2,276.50 $57,870.28 Auditors’ Report The above Balance Sheet has been prepared from the Books of Account, Accounts and Vouchers of The Royal Society of New South Wales, and is a correct statement of the position of the Society’s affairs on 28th February, 1967, as disclosed thereby. We have satisfied ourselves that the Society’s Commonwealth Bonds and Inscribed Stock are properly held and registered. HORLEY & HORLEY Chartered Accountants. Registered under the Public Accountants Registration Act 1945, as amended. 65 York Street, Sydney. 23rd March, 1967. (Sgd.) H. F. CONAGHAN, Honorary Treasurer. ANNUAL REPORTS INCOME AND EXPENDITURE ACCOUNT 10th FEBRUARY, 1966, to 28th FEBRUARY, 1967 $ Advertising 34.66 Annual Social 50.12 Audit : : 76.00 Branches of the Society 50.00 Centenary Celebrations 402.27 Cleaning 327.50 Depreciation 88.94 Electricity 75.44 Entertainment 9.62 Insurance 74.80 Legal Expenses 30.00 Library Purchases 438.42 Miscellaneous : 450.31 Postages and Telegrams 317.57 Printing— J ournal— Vol. 98, Bart 3—Vol, 100, Part 1 $4,402.08 Binding : : 105.00 Reprints 1,325.98 Postages e 193.34 Refund—Sale_ of Back Numbers .. 5.25 Fare—ve Vol. 99 $s 2.00 6,033.65 TCSSis Sale of Reprints 2,033.40 Subscriptions to Journal 849.82 Sale of Back Numbers 211.94 Refund Postages 42.15 Sale of Block .. ae te 20.00 Transfer Printing of Clarke Memorial Lecture : 65.45 Accrued Expenses 139.72 3,362.48 ne 2,671.17 Printing—General 23.88 Rent—Science House Management 2,454.25 Repairs ae 15.34 Salaries 3,329.50 Storage Expenses" = Telephones: 87.14 $11,006.93 $ Membership Subscriptions 1,948.80 Proportion of Life Members’ Subscriptions 12.60 Government Subsidy . 1,500.00 Science House Management—Share of Surplus 4,876.57 Interest on General Investments eae 525.85 Donations .. 10.00 Company Membership ar Sundry Receipts . = Deficit for the Period 2,133.11 $11,006.93 Section of Geology CHAIRMAN : G. S. Gibbons. Abstract of Proceedings, 1966 Five meetings were held during the year, the average attendance being about 12 members and visitors. MARCH 18th (Annual Meeting): Election of Office Bearers was postponed until the next meeting. Address by Dr. G. H. Taylor: ‘“‘ Recent Advances in Coal Petrology ’’’. Dr. Taylor drew attention to the fact that many minerals occur in different coals. The most comron of these are the layer silicates (chiefly clays), quartz and chalcedony, sulphides (pyrite, marcasite, sphalerite), carbonates (calcite, ankerite, siderite) and sulphates (barite, gypsum). As _ well, minerals such as apatite may be locally abundant. The modes of occurrence and associations of many of these in Australian coals were illustrated and discussed. Attention was drawn to the similarity of petrifaction structures formed as a result of replacements of plant tissue by very different mineral species. Some of the practical consequences of inorganic matter in coal during its combustion and carbonization were referred to. MAY 20th: Election of Office Bearers: Chairman : ir D. S. Bridges; Hon. Secretary: Mrs. M. Krysko w [ryst. a) Address by Professor A. H. Voisey: “ Some observations on the Geology of the United States and Miexico.”’ Using colour slides, Professor A. H. Voisey surmmar- ized the geology of the United States and Mexico emphasizing the influence of the main geosynclinal belts and cratonic blocks on the thicknesses and structures of the sedimentary sequences. The wide- spread occurrence of limestone over the cratonic areas and development of Florida was contrasted with the rise of greywackes and turbidites contributing to the development of Puerto Rico and ultimately to portions of the continents. (2) Notes and Exhibits: Mr. E. Lassak exhibited phosphatic rocks from the Sydney area and reported as follows : a. Garie Beach—Thelma Head Area : Three types of rock have been noticed : 1. green gray phosphoritic nodules and pebbles in sandstone (13% P,O,). 2. bands of calcitic phosphorite in sandstone (8% POs). 3. white, green and yellowish nodules of a phosphatic clay in sandstone. All these sarnples occurred in the Bulgo sand- stone (below Bald Hill Claystone)—Narrabeen Group. b. Mona Vale—headland north of Mona Vale Beach: bands and nodules of a dark sideritic phosphorite in sandstone. The phosphatic rocks occur in the Gosford Formation (above Collaroy Claystone)—-Narrabeen Group. Hon. SECRETARY: (Mrs.) M. Krysko v. Tryst. JULY 15th: Notes and Exhibits accompanied by short addresses : a. Professor L. J. Lawrence exhibited specimens and spoke on some mesostructures and macrostructures in orebodies in high grade metamorphites. In such ore- bodies, where ore and country rock have been meta- morphosed at high grade, masses of sulphide-silicate material apparently “‘ intrusive ’’ into the recrystallized orebody as a whole exhibit textures similar to peg- matites. Other intrusives consist of “reef quartz ”’ with sulphides and still others comprise traditionally low temperature minerals such as zeolites, chalcedony, amethyst etc. Professor Lawrence considered these various facies to be the products of a differentiated anatexis (or partial melt) of pre-existing ore. This belief is supported by phase studies in the system Fe-Zn-Pb-S. b. Dr. Koch, in a short paper entitled ‘‘ Mineralo- gical and Gem Treasures of Europe’’, reported on and illustrated by colour slides, outstanding mineralogical and gemstone specimens seen and in part examined by him, in public and private collections of seven European countries. c. Mr. L. Hamilton exhibited specimens of : 1. Devonian ignimbrites from central N.S.W. He pointed out that many of the Silurian-Devonian rocks mapped as rhyolites in N.S.W. are actually ignimbrites. 2. A ‘‘ Fossil fumerole’’, or pyroclastic vein in a Carboniferous ignimbrite from near Seaham, N.S.W. This was compared with similar structures in the Waitahina Ignimbrite in N.Z. 3. Slices of bore cores of the Matahina Ignimbrite from N.Z. arranged in order of depth to show the wide range of textural variations found in ignimbrite cooling units. 4. Slightly pumiceous rhyolite from the flank of Tarawera Volcano (N.Z.) and forms of the basalt involved in the 1888 eruption of the volcano. SEPTEMBER 16th: Address by Dr. A. D. Albani: ‘“ Courses in Geology at Italian Universities and the Organization of Geology in Italy.”’ Dr. Albani gave a brief account of university educa- tion in geological sciences in Italy and introduced the subject by a general review of the primary and second- ary school education with special emphasis on the different type of secondary schools (classical and otherwise). A detailed analysis of the matriculation certificate and its difficulties preceded the description of the University courses (i.e. compulsory as well as optional courses) including class roorn hours, text books generally used, examination systems and extent of independent studies expected of the student. The analysis of the university courses was concluded with the description of the Doctoral Degree system and including the associated three theses. The very few governmental and private enterprises in the field of geology were then examined in the light of the growing demand for positions for geologists. 46 NOVEMBER 18th : a. Dr. Golding exhibited specimens of variolitic spilite and derived metasomaties from Mt. Lightning, in the Coolac Serpentine Belt, N.S.W. The spilite appeared to be of post-peridotite age and its micro- texture indicated that it had cooled rapidly under little cover. The altered rocks included prehnitized and epidotized types, substantially monomineralic prehnite rocks and zoisite rock and a garnet-chlorite rock. b. Mr. G. Gibbons pointed out that an unusual feature was exposed in the Minchinbury Farm diatreme (Fitzpatrick’s quarry) in 1959. This was an irregular sandstone dyke, of which three successive exposures in the quarry wall were sketched at the time. The sandstone consisted almost entirely of quartz grains of medium size, cemented by calcite. Field relations indicate that the sand must have intruded into its present position in some way, presumably by entrainment of the grains in a moving fluid. The origin of the grains was by disaggregation of sandstone, possibly from the Wianamatta Group nearby. The suggestion by A/Prof. Vallance that the calcite cement might be a post-emplacement replacement of clays or other matrix would support an origin from the polymictic Wianamatta sandstones; and the former presence of finer material would certainly make fluidiza- tion a more likely process of emplacement. SECTION OF GEOLOGY c. Mr. L. Hamilton drew attention to the unusual shapes of the igneous fragments in the breccia pipes near Sydney. The irregular shapes of many of the — fragments suggest they were plastic at the time the breccia was formed. These shapes have been further complicated by corrosion and replacement. d. Mr. Jones exhibited specimens of crinoids and “ ™~ brachiopods from Holland as well as a piece of marble used as a tharker to designate the boundary between ancient Egypt and Israel. e. Dr. F. M. Quodling exhibited specimens of Lepto- phloem australie collected from an im situ position close to the rim of the Wolf Creek explosion crater, seventy rhiles south of Halls Creek Township in the Kimberley Division of Western Australia. The stem impressions are preserved in orthoquartz- ites, mapped as Kearney Beds ?Upper Proterozoic, which must now be considered as Devonian in age. The genesis of the crater, whether meteoric or crypto- volcanic was discussed during a showing of colour slides. f. Professor T. G. Vallance exhibited specimen’ from the Undola sill, near Stanwell Park, N.S.W.- Evidence of plastic moulding of sediment adjacent to the uppermost contact with igneous material suggests that the Undola body was emplaced among uncon- solidated detritus and may be, in fact, a L. Triassic flow. Similar moulded contacts are typical of Permian flows in the Port Kembla-Kiama district. Annual Report of the New England Branch of the Royal Society of New South Wales Officers : Chairman: G. L. McClymont. Secretary: D. B. Lindsay. Committee Members: J. H. Priestly, D.-D. H. Fayle, R. L. Stanton, R. H. Stokes, N. T. M. Yeates, J. V. Evans. Branch Representative on Council: D. B. Lindsay. Four meetings were held as follows : 9th May : Dr. R. J. Goldacre, Chester Beatty Research Institute, London. ‘‘ The Chemotherapy of Can- Cena 24th June: Professor G. E. Blackman, F.R.S., Sib- thorpean Professor of Rural Economy, University of Oxford. ‘‘ The limits of primary production ”’. 13th October : Professor F. Fenner, F.A.A., Professor of Microbiology, Australian National University. ““ Recent advances in animal virology ’’. 15th February, 1967: Professor A. Frey-Wyssling, Professor of General Botany, Swiss Federal Institute of Technology, Zurich. ‘“‘ Structure and Ultra-Structure of bell Organelles ’’. Financial Statement Credit : Balance at University of New England Branch, C.B.C. Sydney at May 1966 $205.54 Remittance from Royal Society of New South Wales 1966 as 50.00 4.15 4.59 Interest to June 30th, 1966 Interest to Decernber 30th, 1966 Debit : Honorarium to Miss C. Betteridge for Secretarial Assistance 6.00 Balance $258.28 D. B. LInpDsay, Secretary| Treasurer. Obituaries 1965 - 1966 Robert L. CORBETT (1933) Thomas J. HOLM (1952) Charles W. R. POWELL (1921) George F. SUTHERLAND (1919) Harold B. TAYLOR (1915) Sir Robert D. WATT (1911) 1966 - 1967 Sir Neil Huamilto FAIRLEY (1952) Thelma I. CHRISTIE (1953) Edward J. KENNY (1924) Stephen L. LEACH (1936) Henry J. MELDRUM (1912) Archibald B. B. RANCLAUD (1919) Arthur Spencer WATTS (1919) Sir Neil Hamilton Fairley, who died on 19th April, 1966, was elected an Honorary Member of the Royal Society of New South Wales in 1952. Neil Hamilton Fairley was born at Inglewood, Victoria, in 1891, the son of James Fairley. He was educated at Scotch College. He studied medicine at Melbourne University, gaining thany awards and qualifying M.B., B.S. with first class honours in 1915. He joined the Australian Army Medical Corps and in 1916 he went to Egypt as pathologist to 14 Australian General Hospital where, influenced by Sir Charles Martin, F.R.S., previously Professor of Physiology in Melbourne, he carried out his classical investigations on the pathology, epidemiology and diagnosis of schistosomiasis and published work on malaria, typhus and dysenteries. At the end of the war Fairley worked under Sir Charles Martin at the Lister Institute in London and in 1920 obtained the D.T.M. & H., and M.R.C.P. He then returned to the Walter and Eliza Hall Institute in Melbourne and shortly after accepted the position of Tata Professor of Clinical Tropical Medicine at the Haffkine Institute, Bombay. Returning to Melbourne in 1926 he again worked at the Hall Institute but in 1928 he left for London, where he was appointed to the staff of the Hospital for Tropical Diseases as Assistant Physician and Director of Pathology, and later as Physician and Director of Clinical Laboratory Research. He also established himself in clinical practice in Harley Street and joined the teaching staff _of the London School of Hygiene and Tropical Medicine. _At the outset of the Second World War he was a leading figure in Tropical Medicine, and soon after was elected a Fellow of the Royal Society. | Fairley was Consulting Physician to the Australian Imperial Force shortly after Australian units had reached the Middle East. He was a mainstay of the Australian Army Medical Corps and his influence and _ teaching soon extended throughout the service, and beyond. At the commencement of war in the Pacific, Fairley was Director of Medicine at Land Headquarters and was later adviser on tropical health, as Chairman of an Inter-Allied Committee, to General MacArthur. The troops were now engaged in highly malarious places of unprecedented difficulty. From the outset, Fairley had already decided to replace quinine with ‘‘ Atebrin ”’ as a Suppressive. Within a few months, the measures now introduced had reduced malarial casualties to neghgible proportions. Atebrin suppression of malaria became the order of the day, to the benefit of all. This was Fairley’s greatest contribution to medical science, and his greatest triumph. The importance and value of his findings, freely acclaimed by those in authority at the time, have been in no way diminished by the passage of the years. His work remains an inspiration to those researching in this field. On his return to London after the war, he was appointed as the first Wellcome Professor of Clinical Tropical Medicine at the London School. He made frequent visits to Australia, on one of the last of which he delivered the McCallum Memorial Lecture. The James Cook Medal for 1950 was awarded to Sir Neil Hamilton Fairley in recognition of his distinguished contributions to science and human welfare. He is survived by Lady Fairley and three sons. Thelma Isabel Christie, a member of the Society since 1953, died on 5th July, 1966. After graduating B.Sc. from Sydney University, Miss Christie spent one to two years part-time teaching at both Meriden Girls’ School and the Presbyterian Ladies College after which she was employed for fourteen years as full-time teacher of Geology and Chemistry at Meriden Girls’ School. From 1952 to 1954 she was employed by the Univer- sity of New South Wales where she carried out chemical research under the guidance of Professor R. S. Nyholm. From 1955 until her death she was employed by Colonial Sugar Refining Co. Ltd. as Senior Analyst attached to Central Laboratory, Pyrmont. Miss Christie was also a member of the R.A.C.I., a tember of the Chemical Society of the University of New South Wales, an associate mernber of the Austral- asian Institute of Mining and Metallurgy and a life member of the Sydney University Women Graduates’ Association. E. J. Kenny was born at Marrickville (N.S.W.) on 6th September, 1895. He received his early education at Marist Brothers High School Darlinghurst where Leo J. Jones, then an officer of Geological Survey of New South Wales, and afterward Government Geologist, was a tutor in geology. Later he attended Sydney Technical College. In 1915 he entered the University of Sydney, where he studied geology in the Faculty of Science, as a cadet of the Mines Department. At that time cadets were not permitted to study a full degree course with the result that his studies were restricted to Geology. The result of this was that despite a brilliant academic career he never possessed a degree. He gained High Distinctions in Ist Year and 2nd Year and Honours in Palaeontology at the end of 3rd Year, as well as Professor David’s prize for first place in 2nd and 3rd Years. 48 Mr. Kenny joined the Public Service of New South Wales in December, 1913. His first position was with the Public Works Department where he was engaged on drafting work connected with the proposed Warra- gamba Dams. In April, 1914 he was appointed to the Geological Survey of New South Wales as Field Assistant. During 1917, he acted as part-time Demon- strator at Sydney University by arrangement between the University and the Mines Department. (Sir Warold Raggatt, former Director of the Bureau of Mineral Resources and former Secretary of Department of National Development was one of his students.) The first field assigninent of E. J. Kenny was as an assistant to L. F. Harper in the survey of the Hill End Gold Field in 1918 and soon after with the same gentleman in his survey of the Yerranderie Silver-Lead Field. For the next three years E. J. Kenny acted as field assistant to E. C. Andrews at Broken Hill. With the help of a subsidy from the mining companies a geological survey of the Broken Hill field was under- taken by Andrews during these years, and the results embodied in Memoir 8 of the Geological Survey “‘ The Geology of the Broken Hill District = E: Jo ikenny compiled the chapter summarizing information on the numerous mines outside the Broken Hill Lode and he also surveyed the Pinnacles area (some 10 miles south- west of Broken Hill) in company with E. M. Holder and W. A. Rain. During this time, he also mapped in detail the geology of the then accessible workings of the Broken Hill Mines and did most of the sketch mapping of the geology of the outlying districts such as Thackaringa, Apollyon Valley, Purnamoota, Torro- wangue and Euriowie. This early opportunity of intensive work at Broken Hill was the commencement of a long association with the Barrier Mineral Field involving periodical examina- tion of developments in the various mines as reported in appropriate Annual Reports of the Department. The appointment of E. J. Kenny as Geological Surveyor in 1925 was for the express purpose of creating a position for the study of underground water, thus opening up a new field of investigation to him. This appointment was the inception of the Department’s systematic approach to the problems of the study of ground-water hydrology (previously all investigation had been solely of the Artesian Basins). The initial reconnaissance in the programme embraced four years’ coverage of the Dunedoo-Binnaway and Coonabara- bran-Gunnedah Districts, the report on the latter having been published recently as Mineral Resources No. 40 (although it was forwarded for printing in 1934). During the vears 1929-31 the reconnaissance of the ground-water of the West Darling District was under- taken and the completed report was published as Mineral Resources No. 36. Mr. Kenny’s assistant in this task was another former Under Secretary, Mr. C. St. J. Mulholland. During this survey, for the first time, an official geologist of N.S.W. regularly used a motor car on field work. Following the West Darling survey, geology and rhining activities of the Central North-coast Region (from the confines of Kempsey to Woolgoolga) received his attention for a long period. E. J. Kenny was promoted to Senior Geological Survey in March, 1937 and was then also appointed a member of the Prospecting Board, and in 1937 and 1938 he undertook a survey of the Captains Flat Field, the old mines having been reopened. Although most of his work in the preceding decade dealt with hydrology, another field had also claimed OBITUARIES some of his energy—the study of oil shale and the problems of extraction of oil from it. During 1930-31 he was Technical Assistant to the Shale Oil Investiga- tion Committee. During 1933-34 he was a member (as a N.S.W. Government Nominee) of the Newnes. Investigation Committee and in 1938 he went overseas. as N.S.W. Government Delegate to the Glasgow Con- ference of the British Petroleum Institute. The proceedings of this Conference were related entirely to shale oil. He was deputed to investigate when abroad, problems affecting fuel research and methods of mining thick coal seams. Kenny’s overseas tour in 1938 began with a journey from Mascot to Southampton by air—probably the first example of a N.S.W. State Public Servant travel- ling air on official business and certainly the first. example from this Department. Apart from the research and commercial aspects vf production of oil from coal and shale he made visits to the mines and works of Scottish Oils Limited ; to the Leuna Hydro- generation Plant in Germany producing petrol from brown coal; to the Fischer Tropsch Gas Synthesis. Works at Oberhavsen-Holten in Germany producing petrol and other derivatives; to shale oil plants in Iestonia ; to Unibenzol in Paris; to the British Fuel Research Station at Greenwich and to the I.C.I. Hydrogeneration Plant at Billingham-on- Tees, England. In the United States he spent some time at the U.S. Bureau of Mines Field Research Station, and on the Scranton Coalfield investigating hydraulic storage. His last assignment in the U.S.A. was an unusual one for a geologist. He was to make enquiries and report upon the latest method of taking and recording notes at sessions in Parliament Houses. After receiving relevant information he visited Sacramento, the capital city of California where a mock session of Parliament was arranged to give an opportunity to see the electric system of recording votes in action. His report was forwarded to the then Speaker of the Legislative Assembly in N.S.W. With the outbreak of World War II and resulting petrol rationing, a number of shale oil works producing ““vapourizing spirit’’ came into being. It was part of his duty to ‘“‘ keep an eye”’ on the relevant mining and processing activities. A number of reports of the various activities were published and also furnished to the Excise Branch of the Customs Department. At the request of the Hon. the Minister for Mines he was appointed a Director of National Oil Pty. Ltd., in August, 1941, to watch the interests of the State Government as a debenture holder. He was elected Chairman of the Company in August, 1942, upon the resignation of Sir George Davis from the Board. His association with National Oil Pty. Ltd., at Glen Davis occupied some ten years, for most of the time as Chair- man of Directors, and for eighteen months in 1946-47 with the additional post of full-time Managing Director resident at Glen Davis. The appointment of E. J. Kenny, in 1944, to the position of Assistant Under Secretary established the principle of appointment of technical officers to top adrninistrative positions in the Department. He was _ appointed Under Secretary on 2nd April, 1951. During his Under-Secretaryship in 1956 the Department moved from its quarters in the Lands Department building to Goldsborough House, Loftus Street. He retired on account of ill health on 3rd October, 1957. E. J. Kenny was active in several spheres outside his official duties with the Mines Department. He / OBITUARIES 49 joined the Royal Society of N.S.W. in 1924 and was a Council Member in the period 1940-1942 and was elected Vice-President in the period 1942-1943. In 1940 he was honoured by the invitation to present the Clarke Memorial Lecture to the Royal Society of N.S.W. At the time of his death he was a Life Member of the Society. In 1926 he joined the Australasian Institute of Mining and Metallurgy as Associate Member. Trans- fers to Member and Senior Member followed in 1939 and 1960 respectively. He represented New South Wales on the Council of the Institute in 1955-1956. On a less academic plane his interests were denoted by his membership of the Cricketers Club of N.S.W. and the Pratten Park Bowling Club. In the latter Club he played an active part, holding several adminis- trative positions including that of President, which post he held at the time of his breakdown of health. After his retirement he maintained club membership and continued contact with club activities, but was not able to engage actively in club business or sport. In yet another area of activity E. J. Kenny was intimately connected with the Australian Museum. He was appointed to the Board of Trustees in 1947 and was Chairman of the Standing Committee at the time of his death. After his retirement from the Department of Mines his health improved considerably and it was during this period, when engaged in part-time consulting work, that he became something much more than a name to many of the younger geologists of the Department. The reputation which was known on a personal basis by older geologists and mining men _ became shared with the younger members of the staff, who will remember his courtesy, approachability, wide knowledge and active mentality, which he retained till his death at the age of 71 on 4th February, 1967. Stephen Lawrence Leach, who died on 24th March, 1967, had been a member of the Society since 1936. Mr. Leach received his education at St. Alovsius College, Milson’s Point, where he graduated as Dux and then passed on to Sydney University, where he had a distinguished academic record, graduating as N.A., B.Sc.(Hons.) and later on B.Ec. He was commissioned in the C.M.F. in February, 1934, and throughout World War II he was a major in the Scientific Liaison Bureau. He had many interests in the scientific, academic and community service fields. He was a fellow of the R.A.C.I. and President of the N.S.W. Branch in 1956 ; he was also a Fellow of the Australian Institute of Management. In the academic field, he was a member of Convocation of all three Universities-—Sydney, New South Wales and Macquarie. Mr. Leach was associated with BALM Paints for 27 years, first as Chief Chemist and later as Director of Research and Development. In 1956 he joined Taubmans Industries Ltd. as Group Personnel Con- troller, a position which he held at the time of his death. He is survived by Mrs. Leach, two daughters and a son. Henry John Meldrum, a member of the Society since 1912, was born on 3rd August, 1882, in the small village of Felled Timber Creek near Turmbarumba, in southern New South Wales. 28th June, 1966. During his lifetime he made an outstanding contribu- tion to mathematical education in Australia. His early years were spent in the country around Tumbarumba where he was a pupil under his father at Tumbarumba Public School. Indeed, he finished his formal schooling at this school, but not his education. He did not attend a secondary school, and this fact makes the chronology of his educational development a most interesting one. He died at Manly on On 8th July, 1898, he was appointed a pupil-teacher at Tumbarumba and served in that capacity for 3 years and 9 months. He qualified as a first class pupil-teacher in 1901 and was awarded a full scholar- ship to the Fort Street Training School from the beginning of 1902. His age was then 19 years and 5 months. At the Training School he continued the study of some academic subjects which no doubt helped him to qualify for matriculation at the Univer- sity of Sydney in March, 1903; it also earned him a 2A Classification as a teacher in the Department of Education. His first appointment as a teacher was to the Fort Street Model School in 19038, and at the end of that year he was granted permission to enrol in the Faculty of Science in the University of Sydney where he graduated Bachelor of Science at the pass level in 1907. In 1911 he qualified by examination for a 1B Classi- fication in the Department of Education. He read for an Arts degree by evening study and in 1912 he graduated B.A. with first class honours and_ the University Medal in Mathematics, and was awarded the Barker Scholarship. Following this achievement Mr. Meldrum was invited by Professor Carslaw to assist the evening lectures in Mathematics in the University of Sydney for a number of years. Following his graduation in Science he was appointed as teacher of science at the Model School, Fort Street, in 1907 and in 1912 was promoted to the position of Master in charge of Science. He remained at Fort Street until he was appointed as Lecturer in Mathema- tics to the Teachers’ College from the beginning of 1913. Soin 1913, work in his chosen field, the improve- ment of the teaching of Mathematics in this State, began. Mr. Meldrum’s work at Teachers’ College extended over a period of 34 years. Mr. Meldrum was a foundation member of the Mathematical Association (N.S.W. Branch) and _ its Secretary or Joint Secretary from 1920 until his retirement in 1946. He was President in 1955-56. The papers he read to the Association reflect his wide interests—Approximation, Computation, Courses in Secondary School Mathematics in the Australian States, Ability and Performance in Arithmetic, Statis- tics Applied to Educational Questions, Mathematics in English Schools, Standardised Tests. Like a number of other persons he had felt for a long time that Mathematics teachers in Australia should have their own journal, and when in 1944 the idea of starting such a journal began to take shape, he entered into the project enthusiastically. The journal came into being as The Australian Mathematics Teacher in 1945. Other ways in which he influenced the teaching of Mathematics stemmed from his work with Syllabus Committees and as an Examiner for the Intermediate Certificate courses in Mathematics. 50 OBITUARIES Mr. Meldrum was highly esteemed by his colleagues not only for his efficiency but also for his courtesy to all. Archibald Boscawen Boyd Ranclaud, who died at Newcastle on 22nd January, 1967, was well known in academic circles. The eldest son of the late Colonel and Mrs. Charles Mark Ranclaud, he spent most of his life in Sydney until the past few years when his health began to fail and he returned to Merewether, N.S.W. Mr. Ranclaud graduated a bachelor of science and bachelor of engineering at the University of Sydney. For many years he was head of the physics department at Sydney Teachers’ College and for a period was on loan to the University of Sydney as a physics lecturer. On his retitement Grom the. Teachers .@ollece he accepted a post in the physics department at the university. During the war years he gave special lectures in radiology to technicians. Mr. Ranclaud was well known as an organist. He played at the Great Hall of the University of Sydney on many occasions and at his home church, St. Augus- tine’s Church of England, Merewether. Also, he was an active member of Christ Church) St... Laurence; Sydney. Mr. Ranclaud was a hfe member of the Royal Society of New South Wales having been elected to membership in 1919. Three papers by him were published in the “‘ Journal and Proceedings ”’. He is survived by his two sisters, Mrs. E. Hingston and Miss I. Ranclaud and a brother, Mr. D. Ranclaud. Arthur Spencer Watts was born at Kidlington, Oxfordshire, England on 27th March, 1881, the youngest son of the late Sidney and Martha Anne Watts; his father being a landholder in that district. Mr. Watts was educated in England. A trained horticulturist and seedsman, he came to Sydney in the early years of this century and it was in this field he carried on business until 1951 when he relinquished these interests. Always interested in the affairs of international and national commerce, he was very active in the Chambers of Commerce—both local and _ international—and following is a list of the offices he held in those organiza- tions : President: Australian National Committee of the International Chamber of Commerce—from 1936 to 1940—and Vice-President for several years before, and remained on the Executive Committee of this body until the time of his death. President : Sydney Chamber of Comnmerce—1932/33 and 1933/34. President: Associated Chambers of Commerce of the Commonwealth of Australia—1933/34. Chairman: Taxation Committee, Sydney Chamber of Commerce, from its inception in 1925 until he resigned in 1937. Vice-President : New South Wales Branch Institute of International Affairs, and Member of the Common- wealth Council. Representative, Sydney Chamber of Commerce, in 1926 in the matter of the reorganization of the financial relations of the Commonwealth and State and the coordination of Loan Policy at the Perth Conference. Gave evidence for the Sydney Chamber of Cormmerce before the Royal Commission on Taxation in 1932. Stated the case for the Sydney Chamber of Commerce before the Select Committee of the Senate on the Central Reserve Bank Bill. Gave evidence for the Sydney Chamber of Commerce and the Employers’ Federation before the Royal Commission on Banking in 1936. When Chairman of Parliamentary Sub-Committee of the Council of the Sydney Chamber, gave evidence before Royal Commission enquiring re matters con- cerning the promotion and operations of certain Companies in N.S.W. Was Leader of the Australian Delegation to the International Chamber of Commerce Conference in Washington in 1931, one outcome of which was the Hoover Moratorium of that year, and in 1935 led the Australian Delegation to the Paris Conference of the I.C.C.—one important result of which was the Tri- partite Monetary Agreement of September 1936 (Great Britain, U.S.A. and France). Asa result of the active part taken in discussion on the international conflict between the three great sections, viz. sterling area, gold bloc, and the dollar group, was invited by the German representatives to go to Berlin and discuss monetary and currency matters with Dr. Schacht, then head of the Reichsbank—which invitation was accepted. In 1939 led the Australian Delegation to the Copen- hagen Conference of the International Chamber. Leader of the delegation arranged by the Australian National Committee of the International Chamber of Commerce to represent Australia at an International Business Conference held at Westchester Country Club, Rye, New York, U.S.A. in 1944. Also Leader of the Australian Delegation to the International Chamber Congress held in Lisbon in 1951. In 1939 attended the International Wool Conference in Brussels as the representative of the British National Committee of the International Chamber of Commerce. In 1935 visited China and Japan calling at Tokyo, Shanghai, Hong Kong, Peking etc. and attended conferences of various organizations on trade rela- tions. Report of his conclusions published in 1936 re the Far Eastern situation with particular reference to Japan is significant in view of subsequent develop- ments. In 1941 he made a tour of N.S.W. country districts on behalf of the War Loan drive. Mr. Watts was a member of the Society for many years, having been elected to membership in 1921. Medallists, 1966-67 Citations Clarke Medal for 1967 Professor Spencer Smith-White, D.Sc.Agr., F.A.A. Professor Smith-White, Professor of Biology (Gen- etics), University of Sydney since 1963, was born in Sydney on 14th April, 1909. He is a graduate of the University of Sydney and, after holding various early appointments, including a research position in plant breeding with the N.S.W. Department of Agriculture, he joined the scientific staff of the Museum of Applied Arts and Sciences in 1937 as officer in charge of the Botanical Section. Here he laid the foundations for his lifelong interest in cytology, particularly of the Australian Flora. This interest was transferred to the Botany Department of the University of Sydney to which he was appointed lecturer in 1947, subsequently receiving promotion to senior lecturer and then to reader. In 1961 he was Acting Professor of Botany and during the following year he was elected a Fellow of the Australian Academy of Science. The W. B. Clarke Medal for 1967 is conferred on Professor Smith-White in recognition of his distin- guished contributions to Botany, more especially in the field of cytology, genetics and evolution of the Australian Flora. The Society’s Medal for 1966 Mr. H. A. J. Donegan, M.Sc., F.R.A.C.1., F.R.LC. Mr. Donegan was born in England in 1902 and came to Australia in 1912. After forty-seven years of service with the Depart- ment of Mines N.S.W., he retired as Chief Analyst. Mr. Donegan was the first in Australasia to investigate coal and oil shales by low temperature carbonization, to determine the explosibility of coal and shale mine dusts and other dusts; to test self-contained breathing apparatus used in mine work; to investigate and recommend use and conditions of use of diesel loco- motives in underground mines; to determine ash fusion points of Australian and New Zealand coals and to thoroughly appraise the oil shale seam at Glen Davis. He is the author of a number of Departmental publications and reports and many articles in technical journals both in Australia and Great Britain. Mr. Donegan was elected to membership of the Society in 1929 and was made a life member in 1964. He served on the Council for 13 years, being Honorary Treasurer in 1952 to 1957, was Vice-President 1958 to 1959 and President in 1960. This award is made to Mr. Donegan in recognition of his scientific contributions and for his services to the Society. James Cook Medal for 1966 Sir William Hudson, K.B.E., F.R.S. Sir William Hudson was born in New Zealand and was educated at Nelson College. He studied at the University of London, from which he graduated B.Sc. in Engineering with First Class Honours. He took a post-graduate course in Hydro-Electric Engineering at Grenoble, France. Sir William has had a long career in hydro-electric work and dam construction. Early in his career he was an Assistant Engineer with the hydro-electric section of Armstrong, Whitworth & Co., London. Returning to New Zealand he was the Engineer-in-Charge of construction of the Arapuni Dam. After further experience in New Zealand he came to Australia and joined the Sydney Water Board as Assistant Resident Engineer on the construction of the Woronora Dam, later becoming Chief Construction Engineer and then Engineer-in-Chief of the Sydney Water Board. During this time he was associated with such major projects as the Captain Cook Graving Dock and Warragamba Dam. The Cornmonwealth Government, in 1949, invited him to accept the appointment as Commissioner to launch and implement the Snowy Mountains Hydro- Electric Scheme. Under his direction the Snowy Mountains Hydro-Electric Authority has carried out a vast and complex programme of river diversion works, dam construction and hydro-electric projects, great by world standards. 52 CITATIONS The Edgeworth David Medal for 1966 Roger Jan Tanner, Ph.D. Dr. Tanner was born on 28th July, 1933. He gained the B.Sc. degree with First Class Honours in Mechanical Engineering in the University of Bristol in 1956. He proceeded to the United States for further study on a King George VI Memorial Fellowship graduating M.S. in Electrical Engineering in the University of California at Berkeley in June, 1958. After serving as Lecturer in Mechanical Engineering in the University of Manchester from 1958-61 he took up a position as Senior Lecturer in Mechanical Engineer- ing in the University of Sydney early in 1962 being promoted to a Readership in 1964. He moved to an Associate Professorship in Engineering at Brown University, Providence, Rhode Island, in August, 1966. Dr. Tanner’s research interests are very wide and he has made contributions in a number of areas. His list of publications is very extensive; twenty-three were written during the five-year period he was in Sydney. Archibald D. Ollé Prize Raymond Albert Binns, B.Sc.(Syd.), Ph.D.(Cantab.) Dr. R. A. Binns was awarded the degree of Bachelor of Science with First Class Honours in Geology in 1959 and shared the award of the University Medal and the Deas Thompson Scholarship. He spent the period 1959-1962 working in the Department of Mineralogy and Petrology at Cambridge University, gaining the degree of Doctor of Philosophy for his thesis entitled ‘‘ Metamorphism at Broken Hill’’. Dr. Binns accepted an appointment as lecturer in Geology at The University of New England, Armidale, in Septemnber 1962 and was promoted to the position of senior lecturer in January 1966. Following more detailed research work at Broken Hill, Dr. Binns turned his attention to New England where he studied the distribution and metamorphism of the little known Permian rocks. It was for a paper on this work, accepted for the Browne Volume of the Society’s publications, that he has been awarded the Ollé Prize, the title( of the paper Jbemg = Cranitie Intrusions and Regional Metamorphic Rocks of Permian Age from the Wongwibinda District, North-eastern New South Wales ’’. Rules 1. The aims of the Society The aims of the Society shall be to encourage studies in Science, Art, Literature and Philo- sophy, to promote and further the development of Science and allied disciplines and their applications, to facilitate the exchange of information and ideas amongst the members of the Society and others on Science and kindred topics and to disseminate knowledge relating to Science and allied disciplines and for that purpose the Society may (i) hold meetings for reading and discussing communications ; hold and promote congresses, conferences and exhibitions ; print, publish, sell, lend or distribute the proceedings or reports of the Society or any papers, communications, works or treatises ; make grants of money, books, apparatus or otherwise for the purpose of promoting research or otherwise advancing know- ledge ; promote and encourage education and training in Science, Art, Literature and Philosophy and subjects related thereto ; invite the co-operation of kindred societies and technical bodies, in any manner calcu- lated to promote the objects of the Society ; establish and maintain libraries and collec- tions ; institute and establish and accept trust funds for the purposes of scholarships, grants, awards, prizes and other distinc- tions ; publicise any significant achievements and endeavours in Science, Art, Literature and Philosophy ; provide reading, writing and social rooms and facilities for members of the Society, their friends and guests ; speak and act publicly or privately on matters of interest to the Society. purchase hire lease or otherwise acquire and hold for the purposes of the Society real and personal property and any mghts and privileges and (so far as the law may from time to time allow) sell demise let mortgage or dispose of all or any such real and personal property rights and privileges. (iii) enter into any arrangements or contract (vi) (vii) with any government or other companies, corporations, public body or other authori- ties with a capital Supreme, municipal, local or otherwise that may seem conducive to the Society’s objects or any of them and to obtain from any such government, com- pany, corporation, public body or other authority any rights, privileges and con- cessions which the Society may think it desirable to obtain and to carry out exer- cise and comply with any such rights, privileges and concessions. hire and employ such persons as may be considered necessary for the purposes of the Society and to pay to them and to other persons in return for services ren- dered to the Society salaries, wages, gratuities and pensions and make pay- ments towards insurance and form and contribute to provident and benefit funds for the benefit of any person employed by the Society. invest and deal with any monies of the Society not immediately required for the purpose thereof upon such securities and in such manner as may be determined and from time to time vary and realise such investments. enter into any insurance agreement in respect to any matter in keeping with the objects of the Society. draw accept endorse discount execute and issue cheques promissory notes bills of exchange warrants debentures and other negotiable or transferable instruments or securities. (viii) borrow money from time to time and for such purpose give debentures liens mort- gages charges or other securities over whole or any part of the property real or personal of the Society (so far as the law may allow) enter into agreements bonds or covenants with the lender stipulating for a collateral advantage. 54 RULES (ix) establish subscribe or make advances or donations to promote become a member of affiliate with support or co-operate with any other association or person (whether incorporated or not) whose objects are altogether or in part similar to those of the Society or will promote those of the Society. (x) do all or any of the above things in any part of the world. do or concur in the doing of such acts deeds matters and things and enter into and make such arrangements as are incidental and conducive to the attaining of the above objects or any of them and establish funds for the carrying out of the above objects. In fulfilling the above objects particular attention shall be given to such topics as tend to develop the resources of Australia and to illus- trate its natural history and production. 2. Patrons The Governor-General of the Commonwealth and the Governor of New South Wales shall each be invited to accept the office of Patron. 3. Members of the Society Members of the Society shall be persons desirous of furthering the aims of the Society and who have been elected in accordance with the Rules and By-laws of the Society. 4. Rights, Privileges and Obligations of Members (a) Members shall have the right and privilege (i) to attend meetings of the Society, its Branches and Sections ; (ii) to receive a copy of each publication authorised by Council for gratis distribution to members ; (iii) to use the library in accordance with the By-laws ; (iv) to submit papers and to take part in discussions. (b) No person shall be considered for election unless he has signed the following Obliga- tion : I, the undersigned, do hereby engage that I will endeavour to promote the interest and welfare of the ROYAL SOCIETY OF NEW SOUTH WALES, and to observe its Rules and By-laws as long as I shall remain a member thereof. 5. Termination of Membership (2) Any member of the Society not indebted to the Society for subscription or other- wise may resign membership by giving notice to the Honorary Secretaries. (b) Any member unfinancial for two yearsmay be expelled by resolution of the Council. Such member may be re-admitted on giving a satisfactory explanation to the Council and meeting his financial obligation to the Society. (c) The Council shall have the power to expel any member from the Society provided that such resolution is agreed to by at least twelve (12) of the members present. Before a resolution for expulsion is passed the member concerned shall be afforded any opportunity of presenting any explanation or defence he may think fit. 6. Honorary Members A person of eminent learned attainment or a person who has been a benefactor of this or some other Australian state or a distinguished promoter of the Society may be admitted as an Honorary Member of the Society. The number of Honorary Members shall not at any time exceed twenty. Honorary Membership shall be bestowed in accordance with the By-laws of the Society and on not more than two persons in any one year. Honorary Members shall be exempted from payment of fees and contributions; they may attend the meetings of the Society and they shall be furnished with copies of the publications of the Society but they shall have no right to hold office, to vote or otherwise take part in the business of the Society. 7. Associates Persons may be admitted as Associates of the Society or have their Associateship terminated in accordance with the By-laws. The rights and privileges of an Associate are as set out in the By-laws. 8. The Council of the Society The Business, Properties and Affairs of the Society shall be managed by the Council of the Society which shall consist of (i) The President ; (ii) Five Vice-Presidents of whom one shall be the immediate Past-President if available ; (iii) an Honorary Treasurer ; (iv) an Honorary Librarian ; RULES (v) two Honorary Secretaries ; (vi) one representative from each of the Branches ; (vii) eight ordinary Members of Council. 9. The Executive Committee (a) There shall be an Executive Committee which shall deal with any matters referred to it by Council and with any matters which concern the Council with regard to which action should not, in the opinion of the Executive Committee, be postponed until a meeting of the Council. In respect to all such matters the Executive Committee shall have and may exercise between meet- ings of the Council all powers and functions of the Council except (i) to make, alter or repeal By-laws ; (ii) approve of the expulsion of a member or an associate under Rules 5(b) and 6; (iii) create or dissolve a Branch or a Section of the Society or vary the geographical territory of a Branch ; (iv) declare the office of a member of Council vacant ; (v) fill a vacancy on the Council. The Executive Committee shall report on any action taken under (a) above to the Council meeting immediately following such action. The Executive Committee shall consist of the President, the Honorary Secretaries, the Honorary Treasurer, the Honorary Librarian and the immediate Past-Presi- dent. The quorum for an Executive Committee meeting shall be three. (2) 10. Election of Members of Council (2) The President, Vice-Presidents, Honorary Treasurer, Honorary Librarian, the Hon- orary Secretaries and the eight ordinary Members of Council shall be elected at the Annual General Meeting ; The representative of any Branch shall be chosen by that Branch ; The declaration of the result of the election of Members of the Council shall be the last item of formal Business at the Annual General Meeting. The newly elected Council shall take office immediately the declaration is made ; DD 55 (ad) Any financial member of the Society shall be eligible for nomination for any position on the Council of the Society except that no member shall be eligible for election as (i) President if he has served as Presi- dent for the whole of the preceding year ; (ii) an ordinary Member of the Council if he has been elected to the Council for the five preceding years ; Provision shall be made for any financial members of the Society to record an absen- tee vote as set out in the By-laws ; No ballot for the election of members of the Council shall be valid unless twenty members at least record their votes ; Election shall be conducted in accordance with the By-laws ; Any vacancy on the Council may be filled by election at a Council Meeting. Mem- bers of the Society shall be notified at the first general meeting following such action. 11. Subject to these rules, questions arising at any meeting of the Council or of the Executive Committee shall be decided by a majority of the votes cast by members and their proxies. Each member present shall have one vote. The Chairman shall have a deliberative vote and a casting vote. 12. Termination of Membership of the Council The office of a Member of the Council shall be vacated if (i) he ceases to be a member of the Society ; (ii) he, by notice to the Society, resigns his office ; (iii) he absents himself from three consecutive meetings without reasonable excuse ; (iv) his office is declared vacant by a resolution of the Council on the grounds that he is no longer able to carry out the duties of his office through prolonged illness or other causes ; he, not being a representative of a Branch, his office is declared vacant by a resolution of a general meeting of the Society at which at least 25 financial members are present ; or being a representative of a Branch, his office is declared vacant by a resolution of a meeting of the members attached to that Branch ; he becomes bankrupt or makes any arrangement or composition with his creditors ; S (vi) 56 RULES (vii) he is found lunatic or becomes of unsound mind ; (viii) he is directly or indirectly interested in any contract or proposed contract with the Society and fails to declare the nature of interest to the remaining members of the Council. 13. Council Meetings (a) The Council shall meet during the fort- night preceding each general meeting of the Society. (6) The Honorary Secretaries shall call a meeting of the Council (i) by resolution of Council ; (ii) at the request of the President ; (ili) at the request of three members. (c) Due notice, in writing, shall be sent to each Member of the Council at least three days before such meeting. (d) The quorum for meetings of Council shall be six members. (ec) The representative of a Branch may, by instrument in writing, appoint a member of the Society as his proxy to act on his behalf at any or all meetings of the Council which he is unable to attend. At meetings of the Council and of the Executive Committee, the President or in his absence the Past-President or in his absence one of the Vice-Presidents shall be chairman. In the absence of the President and Vice-Presidents the mem- bers and proxies present shall choose one of their number to be chairman. 14. Duties of the Executive Members of Council The duties of the Executive Members of Coun- cil are as set out in the By-laws. 15. Committees (a) The Council may appoint Committees consisting of such member or members of the Council and such other persons as it thinks fit. (b) The President, the Honorary Treasurer and the Honorary Secretaries shall be members ex officio of all such Committees. (c) Any Committees so formed shall (i) work within the terms of reference prescribed for it by the Council and (ii) report its findings and/or actions to Council. 16. Branches (a2) To further its objects the Society may establish Branches on a _ geographical basis. ; (6) The Council may establish or disestablish a Branch, or vary the geographical territory of a Branch. (c) Each Branch shall be constituted and its affairs shall be carried out in accordance with these Rules and with the provisions of the By-laws from time to time in force. (2) Except as otherwise provided in the By- laws the members of the Society normally resident in the territory of a Branch shall be members of that Branch. 17. Sections (a) To further its aims within specific subjects, the Society may establish Sections. (b) The Council may establish or disestablish a Section. (c) A Section shall be constituted and its affairs shall be carried out in accordance with these Rules and with the provisions of the By-laws from time to time in force. 18. Meetings of the Society The meetings of the Society shall comprise the Annual Meeting, Ordinary General Meetings and Special Meetings. At least seven days’ notice of each meeting shall be given to members. (2) The Annual General Meeting of the Society shall take place during the month of April. Unless the Chairman decide otherwise the Business shall be transacted in the following order: Minutes of the preceding Annual General Meeting Ballot for Election of Members | Introduction and Admission of New Mem- bers Announcement and Presentation of Awards Presentation of the Annual Report of the Council Presentation and Annual Report of the Honorary Librarian Presentation of the Annual Income and Expenditure Account and the Balance Sheet of the Society Election of Auditor Ballot for Election of Members of the Council (if required) RULES 57 The Address of the Retiring President Announcement of the Result of the Election of Members of Council Installation of the President-Elect (b) There shall be at least eight Ordinary General Meetings each year. These meet- ings shall be held on the first Wednesday of the month unless otherwise decided by the Council. Unless the Chairman decide otherwise, the Business of the Ordinary General Meeting shall be in the order prescribed in the By-laws. (c) The Council may whenever it thinks fit and shall on the receipt of a written request signed by at least 30 members convene a Special Meeting. 19. Subject to these Rules questions arising at any meeting of the Society shall be decided by a majority of the votes cast by the members present. Each member present shall have one vote. The Chairman shall have a deliberative vote and a casting vote. 20. A notice may be given by the Society to any member either personally or by sending it by post to him at his address supplied by him to the Society for the giving of notices to him. 21. Visitors Visitors may be admitted to the meetings of the Society in accordance with the provisions of the By-laws. 22. Publications The conditions relating to the submission, acceptance or otherwise and publications of material by the Society shall be as prescribed in the By-laws. 23. Subscriptions (2) Conditions relating to the payment and remission of application fees, annual sub- scriptions and levies of members and associates shall be as prescribed in the By-laws. (5) Members and Associates may not be levied in any one year in excess of one annual subscription over and above the annual subscription fixed for that year. (c) Council shall have the power to waive or alter the application fees, annual sub- scriptions and levies in special circum- stances. 24. Alteration to the Rules of the Socrety No alteration or addition to the Rules of the Society shall be made unless (i) the full text of the resolution proposing the alteration or addition shall be com- municated in writing to the Honorary Secretaries who shall place it on the next notice paper for an ordinary general meeting ; the resolution is placed on the notice paper for and submitted to a subsequent ordinary general meeting or special meet- ing held not less than 6 days after the meeting referred to in (i) above, at which at least 30 members are present and two- thirds of the members present support the motion ; the resolution is placed on the notice paper for and submitted to a further meeting held not less than 6 days after the meeting referred to in (ii) above at which at least 25 members are present and the majority of those voting support the motion. E (iii) 25. By-laws The Council shall make, alter or repeal such By-laws as it deems necessary to regulate the affairs of the Society provided that such changes in the By-laws shall be notified to all members of the Society not less than 7 days before an ordinary general meeting. Such amendment shall become operative after that meeting unless a resolution to the contrary is passed at that meeting. 26. The Seal The Council shall provide for the safe custody of the Seal which shall be used only by authority of the Council and every instrument to which the Seal is affixed shall be signed by two members of the Council. 27. Management of Funds and Property (2) The Council shall have control over the management of the funds and of the property of the Society. (0) Accounts and Audit (ba) The Council shall cause books of account to be kept in such a manner as properly represent the state of the Society's affairs and explain its transactions and to enable them to be conveniently and properly audited. 58 (06) (6c) (od) RULES The books of account shall be kept at the office of the Society or at such other place as the Council shall think fit and shall always be open to inspection of members of the Coun- cil. They shall be open for inspec- tion by members during business hours and shall be subject to any reasonable restrictions which may from time to time be laid down by the Council. The financial year of the Society shall terminate on the last day of February. The Council shall cause to be pre- pared and placed before the Society at its Annual General Meeting an Annual Income and Expenditure account and Balance Sheet made up to the end of the financial year immediately preceding the Annual General Meeting. (be) The Annual Balance Sheet shall be signed on behalf of the Council by two members thereof and shall have attached to it a report by the — Council with respect to the state of the Society’s affairs and the auditor’s report, all of which shall be printed in the Proceedings of the Society. One or more auditors who shall be Chartered Accountants or Public Accountants shall be elected each year at the Annual General Meeting to audit the affairs of the Society for the ensuing year. An auditor may be removed from office by a resolution passed by not less than two-thirds of those voting at a Special Meeting called for the purpose. The quorum for such a meeting shall be 30 members. Council shall have the power to fill any casual vacancy in the office of auditor of the Society. By-Laws 1. Members of the Soctety (2) (0) Every candidate for admission as a mem- ber of the Society shall be recommended according to a prescribed form of certi- ficate (Appendix A) by not less than two members to one of whom the candidate must be known personally. The certificate together with the entrance fee and the first annual subscription shall be delivered to one of the Honorary Sec- retaries and shall be considered at the next ensuing Council Meeting. The names shall be placed on the notice paper of the following two ordinary general meetings of the Society and shall be read at those meetings. The vote for election of a new member shall take place at the meeting at which the certificate is read for the second time, provided not less than twenty members are present ; otherwise it shall be deferred until the first meeting thereafter at which not less than twenty members are present. The election shall only be agreed to if at least four-fifths of the members eee express their approval. Any candidate whose election has not been agreed to shall have the annual subscrip- tion refunded. Every new member shall be notified of his election and shall be supplied with a list of members and a copy of the Rules of the Society. At the first ordinary general meeting at which a new member attends after election he shall be presented to the Chairman who addressing him by name shall say “‘ In the name of the Royal Society of New South Wales I welcome you as a member thereof.”’ 2. Associates (2) On the recommendation of one member of the Society on a prescribed form of certi- ficate the Council may admit as an associate (i) a person under the age of 25 years or (ul) a close relative of a member. (b) An associate shall have the right (i) to receive notice of and attend meet- ings of the Society, its Branches and Sections (ii) to read in the library (iii) to submit papers and to take part in discussions at meetings of the Society, its Branches and Sections. (c) An associate shall not have the unqualified right (i) toreceive, free of charge, any publica- tion of the Society (11) to borrow books or periodicals from the library (iii) to vote at any meeting of the Society, its Branches and Sections (iv) to hold office on the Council. (zd) Associateship shall be terminated (i) by the associate submitting a notice in writing to the Honorary Sec- retaries (1) by the associate ceasing to qualify under (a) above (iii) by motion of the Council if not less than two-thirds of those voting express approval of such termination. (e) Every new associate shall be notified of his admittance. (f) The name of each new associate shall be placed on the notice paper of the ordinary general meeting immediately following his admission. 3. Honorary Members Honorary Members shall be elected on the unanimous vote of Council. The election shall be communicated to members at the next following general meeting of the Society. 4. Fees, Subscriptions and Levies (a) Honorary Members of the Society shall not be required to pay any application fee, annual subscription or levy. BY-LAWS All matters of doubt relating to fees, subscriptions or levies shall be decided by the Council. An application fee as set out hereunder shall accompany each application for membership or each application to become an associate of the Society. This fee shall remain the property of the Society. Fee for application to become a member when (i) applicant is not an associate $3.00 (11) applicant is an associate $2.00 Fee for application to become an associate $1.00 (da) The annual subscription to be referred to the Finance Committee for decision by April. Annual subscriptions lodged with applications shall be returned to the applicant if for any reason the applicant does not become a member or associate of the Society as the case may be. The annual subscription shall become due on the first day of April for the current financial year. Life membership to be compounded by members over sixty (60) only. (db) x\N 10 15 . 20 25 30 35 60 78 72 64 50 30 0 65 72 66 58 48 30 0 70 66 60 52 44 28 0 75 60 54 48 40 28 0 N=number of subscriptions already paid by a member. x =age of thember. (de) The annual subscriptions for an associate who has paid a Life Com- position fee and who transfers to membership shall be the difference between the annual subscription for a member and for an associate. The life composition fee in such a case shall be the difference between the appropriate fees corresponding to the age of the applicant at the time he compounds his membership sub- scription. 5. Election of Council (2) Any financial member who is not dis- qualified by the Rules of the Society may be nominated for any position on the Council. Such nomination, signed by two members of the Society and counter- signed by the nominee, shall be notified to the Honorary Secretaries before the first day of January. After receipt of nominations from members of the Society, the Council may make additional nominations, if deemed necess- ary, and shall ensure that there are, at least, sufficient candidates to fill all posi- tions on the incoming Council. A complete list of the names, in alpha- betical order, of those correctly nominated for each position, together with the nominators, shall be posted to each financial member of the Society not less than 21 days before the day appointed for the Annual Meeting. The retiring Council shall appoint a Returning Officer for the election. Should no ballot be necessary, the Return- ing Officer shall advise the Council and those nominated shall be declared elected at the next Annual General Meeting. Where an election is required, such election shall be by secret ballot. Each member voting shall be entitled to vote for as many candidates as there are vacancies to be filled. Those candidates receiving the greater number of votes shall be declared elected. The ballot for the election of the Council shall take place at the Annual General Meeting. However, any member may make a postal vote if desired. The ballot paper for the election of the Council shall contain in alphabetical order names of candidates correctly nominated for each position on the Council. 6. Postal Vote for the Ballot for Election of the Council (2) A member desiring to cast a postal vote shall notify the Returning Officer in writing in sufficient time before the date of the ballot, and in any case at least fourteen days before such date. On receipt of sucn notification, the Return- ing Officer shall forward a ballot paper to the member. The ballot paper duly marked shall be invalid unless returned to the Returning Officer before 12 noon on the day which the ballot takes place. 7. Duties of the Honorary Secretaries (2) The Honorary Secretaries shall (i) conduct all the correspondence of the Council and the Society (0) BY-LAWS (ii) attend all meetings of the Council and all meetings of the Society and take and record the minutes of such meet- ings (iii) edit the Journal and Proceedings of the Society (iv) be responsible for the safe custody of books, maps, specimens and other property of the Society (v) acknowledge all donations to the Society (vi) give due notice of all meetings of the Society and the Council (vii) keep a record of attendances at the Council meetings. With the approval of the Council, the Honorary Secretaries may delegate any of the above duties to a member of the Council or to an employee of the Society. 8. Duties of the Honorary Treasurer (a) (6) The Honorary Treasurer shall (i) receive all monies paid to the Society and deposit such monies into the account or the accounts of the Society (ii) make such disbursements as shall be authorized by Warrant from the Council (iii) keep all financial books and financial records of the Society (iv) arrange for the audit of the Society’s accounts at such times as shall be directed by the Council (v) prepare and present a duly audited Annual Balance Sheet for the finan- cial year of the Society. With the approval of the Council, the Honorary ‘Treasurer may be assisted in any of the above duties by a member of the Council or by an employee of the Society. 9. Library (2) (0) To assist the Council in the control of the Library, the Council may appoint a Library Committee, the powers, duties and terms of reference of which shall be determined by the Council. The Library shall be open for the use of members daily, Monday to Friday, from 9.30 am. to 4.30 p.m. except in the absence of the staff. (c) 61 Any publications or other item in the Library shall be available for reference by members in the Library, and shall not be removed without the Librarian’s per- mission. Members may borrow a publication from the Library for a period not exceeding fourteen days subject to signing for it in the Librarian’s record. Borrowing shall normally be for a period not exceeding fourteen days but an extension of time may be arranged on application. Any publication not returned when reques- ted by the Honorary Librarian, or returned damaged, shall be replaceable at the expense of the borrower. Members requiring a copy of an article must first obtain the consent of the Honorary Librarian and must bear the expense of reproduction. 10. Order of Business at an Ordinary General Meeting Minutes of the previous Ordinary General Meeting Minutes of all Special Meetings held after the previous Ordinary General Meeting Business arising out of the Minutes Announcement of names of candidates for membership Ballot for election of members Introduction and Admission of new mem- bers Communications from the Council Communications from the Branches and Sections Motions from the preceding Ordinary General Meeting Announcement of papers accepted for publication in the Journal General Business Special Business The Chairman shall be the sole arbiter on the nature of the General Business transacted at meetings. The Chairman shall have a deliberative and a casting vote on any motion. 11. Visitors It shall be competent for the Council or the Chairman to restrict attendance of visitors at meetings. 62 BY-LAWS 12. Publications (2) Material submitted by members for pub- lication or by communication to the Society shall be addressed to the office of the Society, Science House, 157 Gloucester Street, Sydney. Material submitted for publication shall be in duplicate and accompanied by four copies of an abstract and shall be submitted in accordance with the Society’s “ Instruc- tions to Authors ”’. The receipt of material shall be acknow- ledged by the Honorary Secretaries. No material shall be published or formally communicated to members except with the approval of the Council. Material not accepted by the Council shall be returned to the author forthwith. The original copy of any material accepted for publication by the Society together with illustrations, diagrams, etc., shall become the property of the Society and will not necessarily be returned to the author. (fa) The author of material which is accepted for publication by the Society shall not publish such mat- erial elsewhere, except with the permission of the Council until the paper or an abstract thereof shall have appeared in a publication of the Society. Reproduction of a paper, or part thereof, by any mechanical or photo- graphic means whatsoever is pro- hibited except with the written consent of the Council. Except in special circumstances, material from non-members will not be accep- ted for publication. The author shall be liable for costs occa- sioned by alterations or additions made to material, at his request, at or after the submission of the printer’s proofs. Reprints shall be supplied to authors under the following conditions : (1a) Twenty-five (25) free copies shall be provided of each paper published. (2b) Additional copies of reprints may be obtained at rates obtainable from the Society’s office provided that such reprints are ordered when the printer’s proofs are returned to the Honorary Secretaries. 13. Branches (2) (0) There shall be a New England Branch of the Society whose region shall extend fifty miles from Armidale. (ba) A member of the Society who is normally resident in a region in which there is a Branch shall be deemed a member of that Branch. Membership of the Branch shall cease (i) on the resolution of the Council at the request of the Branch Committee or (ii) if the member submits his resignation from the Branch in writing to the Honorary Secretaries of the Society or the Honorary Secretary of the Branch or ceases to be a member of the Society or ceases to reside within the region of the Branch. (oc) A member not normally resident within the region of a Branch may at his own request and with the agreement of the Branch Committee be made a member of a Branch by the Council. Membership of a Branch shall not entail any additional application fee or membership subscription from a member of the Society. (06) An associate of the Society may be attached to a Branch and the provisions of the preceding By-law for membership of the Branch shall apply, mutatis mutandis, to such attachment. A Branch may frame Rules for the conduct of its own affairs within the framework of the Rules and By-laws of the Society ; such, Rules shall be subject to the approval of the Council. (ea) The management of a Branch shall be vested in a Branch Committee which shall consist of a Chairman, Vice-Chairman, Honorary Secretary, Honorary Treasurer and such other members as may be decided by the Branch. One member of this Com- mittee shall be the representative of the Branch on the Council. The offices of Honorary Secretary and Honorary Treasurer may be com- bined. (f) BY-LAWS Only members of the Branch shall be eligible for election to the Branch Committee. The first Committee of a Branch shall be elected at a meeting con- vened by the Council to inaugurate the Branch. At such a meeting only members of the Society nor- mally resident within the region of the Branch shall be eligible for election or eligible to vote. The Committee of a Branch shall be elected annually at the Annual General Meeting of the Branch. No member of the Branch Committee shall retain office if he ceases to be a member of the Branch. In the event of the position of Chair- man of a Branch becoming vacant this position shall be filled by the Vice-Chairman or if he is unavailable the Branch Committee shall elect a Branch Chairman from among the members of the Branch. A casual vacancy on a Branch Com- mittee, other than in the position of Branch Chairman, shall be filled by the Branch Committee at _ its discretion. An Annual General Meeting of the Branch shall be held each year in the month of March at which a written report of the activities and finances of the Branch shall be presented and at which officers shall be elected for the ensuing year. A copy of the written report shall be forwarded to the Council before 15th March each year. Ordinary meetings of a Branch shall be convened by the Committee at such times and places and in such manner as the Committee decides. The Committee may when it thinks fit convene a Special Meeting of the 63 Branch. It shall convene such a meeting on receipt of a request signed by at least ten per cent of the membership of the Branch or by five members, whichever is the greater. No business shall be transacted at the Annual General Meeting or Special Meeting of a Branch unless ten per cent of the membership of the Branch or five members, whichever is the greater, are present. The Council may contribute from the funds of the Society towards the formation and maintenance of a Branch. The Committee of a Branch shall have power to accept monies and spend these in addition to those granted to it by the Council provided such monies are used solely to further the objects of the Society. 14. Sections There shall be a Geological Section of the Society. Any member of the Society shall be entitled to become a member of a Section without any additional fee. The management of a Section shall be vested in a Committee which shall consist of a Chairman, Honorary Secretary and such other members as may be decided by the Section. (ca) The first Committee of a Section shall be elected at a meeting con- vened by the Council to inaugurate the Section. The Committee of a Section shall be elected annually at a general meeting of the Section to be held in March. A report of the year’s proceedings shall be made in sufficient time for inclusion in the Annual Report of the Council. (cb) OFFICERS FOR 1967-1968 Ae - His Fuca nee: THE ‘Governor ¢ OF Ne EW ieoure ‘Watss, a RODEN CUILER, v. VC K.C.M. fs C.B.E. a ee se a =. ae "President - Ee aoa He aes "ANGUS H. Low, A) ee te cane ope Bie, oe he eee _Viee-Presidents: : = Paes he 3S en ve ALAN A DAVY run We HG. POGGENDOREF. B.ScAg, RE WwW. Le FEVRE, ‘D.Se., ERS. F.A.A. weit yaad OTE D.Se, ri, , . < ie Xetra / iw 2 : “e . 5 ee AO SS ali ee eae ag Honorary Secretaries : ‘L. GRIFFITH, ee Q aa eae ie A REICHEL, rh. Dd. M.Sc. MA FETT IN ay Se us tlie by Vase 4 me oe ae i e) meee Pr ee ra "Honorary, enue Bite Ge oes eo hae . WLR. CONAGHAN, Mie a ee ye es. eee oe ne Os. ye | Members of Council’ 1 ie aX BURG, AST... po ee te pe B. LINDSAY, B.Se., M.A., D.Phil, ei on ‘CAMERON, M.A., B.Sc. ea) 3 DLC. ka, pee Gy NEUBAUS? Mmse.30 7). a As GRIFFIN, B.se. | ~. J. P.. POLLARD, pip.app.chem, © 4 es eas BA. B.seag. -—s—~—Ss M, J. PUTTOCK, Base. (ng.), A.mnst.r. ¥SKO v. et ois B. Sey Grad, Dip. a i) H, ROBERTSON, Se . Sr ye ee vai h x ap ce tee : z at = ee Fria ~ E y om Bn, fe ee x fi SN \ om <7y = . a — \G ) Cin Ae v ; 4 j : ; & eS us} mee Fy = ‘ ea tee Sky = = ; ! = BE fe bk \ 2 a5 Rae 7S: a ?, ey ieee “NOTICE ‘The Royal Bociciy of ‘Hew South ‘Wales ain’ in. 1821 2 as ihe fe # Philosophical Society of. ustralasia ”; after an interval of inactivity it was: resuscitated in 1850 under the name of the™ ‘ Australian Philoso ophical: Society”, by which title it was known until 1856, when the name was changed to the ‘‘ Philosophical Society of New South Wales’. In-1866, ‘by. the sanction of Her _ ee oe ious ee ae Victoria, the oes assumed its Bue ees hue, 2 and was s incorporated arliat sf es i : vet ks : X ae ee + i a 1 > : 5 SS S jay = xs OE ee c z Sat Ww. Hh. Robern sua ee ie ene ae SO ee ee Some ‘parang of the © Toolong Range K Kosciusko State Park, New South Ae OT ee “PUBLISHED BY THE socInTY: PAR earn = ee ge SCrENCE ‘HOUSE. GLOUCESTER AND ESSEX STRERTS, ‘SYDNEY one é Sak ie z ie Sees Nea ob pay te eS Coen ee oe 26, aoe ee ~ Sydney, NOTICE TO AUTHORS — So oe General. Manuscripts should be addressed to the Honorary Secretaries,-Royal Society of New South Wales, 157 Gloucester Street, Two copies of each manuscript are required: the original typescript and a carbon copy; together with two additional copies _ of the abstract typed on separate sheets. » Papers should be prepared according to the” They. should be as concise as possible, consistent. with general style adopted in this Journal.” adequate presentation. Particular attention should be given to clarity of Ged et ‘and good prose style. The typescript should be double-spaced, preferably on quarto paper, with generous side margins. Headings should be typed without underlining ; if a paper is long, the headings should also be given in a table of contents typed on a separate sheet, for the Suidance of the Editor. The approximate poettoks of ee Plates and Tables should be indicated’ in the text between parallel ruled lines, Captions of Figures and Plates should be typed on a separate sheet. The author's paper, in cases of papers written jointly. - Abstract. An informative ‘abstract ‘should be provided at the commencement of each paper for the guidance of readers and ok use in abstracting journals. Tables. Tabular matter should be tye: written on separate. sheets, arranged for the most economical presentation on the printed page. Column lines should not be ruled in. Units of measurement should always be indicated in the headings of the columns or rows to which they apply. Tables incorporating both text and © line diagrams (including dotted lines and shading) should be submitted in a form suitable for direct eo by eee = blocks. References. year of publication, e.g.: Vick (1934); the end of the paper they should be “arranged with the atmospheric humidity. geological subjects. ped Geological ‘Papers, | circumstances, authors submitting of or comment on the new - appropriate ‘nomenclature -sub-comz the Geological Society of Australia. ‘Society’ receive 25 copies of ‘each ‘paper | Additional copies may be -purchased ‘provided — BS » they are erent by the euticr baay return ning a eee OTe a s ce Tee 3 ; Retsrences are to be ated: ae the text by giving the author's. name. and he alphabetically giving the. authoret name Pees: initials, the year of publication, the title of the a paper (if desired), the abbreviated title of. ries a journal, volume number and pages, thus: — Vick, C. G., 1934. Astr. Nach., 253, 277, : J. Proc. Roy. Soc: N.S.W.~ _ Captions of Figures and Plates should whe q _ typed in numerical order on a Lsecernte sheet. ig ‘Line Dispennd: Line’ ms, fully lettered, should be made with dense “Wade ink» on either white bristol board, blue linen or pale-blue ruled graph paper. ‘Tracing paper is unsatisfactory because it is subject to attack by silverfish and also changes its shape in sympathy - The thickness - of lines and the size of letters and numbers — should be such as. to permit Bhotbgraphic. reduction without loss of de Dye-line or photographic » seopies- ee ‘each diagram should be sent. so that the. originals - need not be sent to referees, thus beeen ge Z: possible damage to a diagr Ss while in Sage a ~ institutional | or residential - address should be given in the title of the the relevant author's initials being. attached in brackets to the appropriate, aie®, preferably mounted on white car , and should — show as. much contrast as possible since contrast _ is lost in reproduction - of ‘hall in photographs of distant scenery and When several p are to be combined in one Plate, the photographs. should be mounted. on a sheet of white” bristol board in the Be gedie eure for final reproduction. - *s Pe gi “ieee in” “special manuscripts in which new stratigraphical “habia are o proposed must also submit the letter of af approv: iedee 9g ‘the | ni see ofa — of the. Reprints. Authors who are me STATEMENTS MADE AND THE OPINIONS EXPRESSED THEREIN. bc He Res Po 7 4 “6S ‘ce Ps ee abbreviated form of the title of this aoe! 2 os a 4g he eg Hhokderaplen -Photberaphs: Saanilis te in- 4 cluded only where essential, should be glossy, 5 pe. _ f-tone blocks. “J 4 Particular attention should be paid to contrast _ j se , Ws "THE AUTHORS OF : PAPERS ARE ALONE RESPONSIBLE FOR THE = et an Ee ) Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 65-71, 1968 Precise Observations of Minor Planets at Sydney Observatory during 1965 and 1966 W. H. ROBERTSON The programme of precise observations of selected minor planets which was begun in 1955 is being continued and the results for 1965 and 1966 are given here. The methods of observa- tion and reduction were described in the first paper (Robertson, 1958). All the plates were taken with the 23 cm. camera (scale 116 ” to the millimetre). Four exposures were made on each plate. In Table I are given the means for all four images for the separate groups of stars at the mean of the times. The differences between the results average 08-028 sec § in right ascension and 0”-40 in declination. This corresponds to probable errors for the mean of the two results from one plate of 08-012 sec 6 and 0”-17. The result from the first two exposures was com- pared with that from the last two by adding the movement computed from the ephemeris. The means of the differences were 08-012 sec 3 in right ascension and 0”-15 in declination. It is expected that the two results from each plate will be combined into one when they are used. However they are published in the present form so that any alteration of the positions of the reference stars can be conveniently applied by using the dependences from Table II. No correction has been applied for aberration, light time or parallax but the factors give the parallax correction when divided by the distance. The observers at the telescope were W. H. Robertson (R), K. P. Sims (S) and Harley Wood (W). In accordance with the recommendation of Commission 20 of the International Astrono- mical Union, Table II gives for each observation the positions of the reference stars and the dependences. The columns headed ‘ R.A.” and “‘ Dec.” give the seconds of time and arc with proper motion correction applied to bring the catalogue position to the epoch of the plate. The column headed “Star” gives the number from the Yale Catalogue (Vols. 11, 12, 13, 14, 16, 17, 20, 21). The plates were measured by Miss R. Bull, Miss J. Doust and Miss B. Frank who have also assisted with the reductions. Reference ROBERTSON, W. H., 1958. j. Roy. Soc. N.S.W., 92, 18. Sydney Observatory Papers No. 33. TABLE I R.A. Dec. Parallax No. (1950 - 0) (1950-0) Factors h m S fe) hi a” S A 1 Ceres 1965 U.T 673 July 05° 81154 00 23 27-844 —10 35 18-08 +0:008 —3-46 S 674 July 05-81154 00 23 27-782 —10 35 17-98 675 July 13-80071 00 27 23-096 —10 45 41°34 +0:033 —3°44 W 676 July 13-80071 00 27 23:017 —10 45 41-14 677 July 15-78215 00 28 10-742 —10 49 36°07 —0:009 —3-43 W 678 July 15-78215 00 28 10-702 —10 49 36-20 679 July 21-77002 00 30 07-078 —ll 04 41-08 0-000 —3:39 R 680 July 21-77002 00 30 07-098 —ll 04 41-96 681 July 26-76185 00 31 10°614 —ll 21 00-59 +0:-015 —3-35 S 682 July 26- 76185 00 31 10-594 —ll 21 00-24 683 August 09-71560 00 31 15-149 —12 23 28-93 —0-010 —3-21 R 684. August 09-71560 00 31 15-118 —12 23 28-62 685 August 31-65207 00 22 36:912 --14 36 11-36 —0:003 —2°-89 R 686 August 31-65207 00 22 36-898 —14 36 11-43 66 W. H. ROBERTSON TABLE I—continued R.A. Dec. Parallax No. (1950-0) (1950-0) Factors h m S 2) ut Y Ss u 1 Ceres—continued 687 Sept. 15- 61603 00 ll 42-856 —16 06 45:82 +0:037 —2:67 W 688 Sept. 15-61603 0O ll 42-914 —16 06 45-63 689 Sept. 20- 58802 00 O7 36-012 —16 32 19-66 0-000 —2:-60 R 690 Sept. 20- 58802 00 O7 36-064 —16 32 20-24 691 Oct: 12-50649 23 50 03-882 —17 35 35-94 +0:030 —2-45 W | 692 Oct. 12-50649 23 50 03-833 —17 35 37-12 | 693 Oct. 21-49097 23 44 31-124 —17 34 00:38 +0:012 —2:45 R | 694 Oct. 21-49097 23 44 31-054 —17 34 00:10 | 695 Nov. 08- 43273 23, 38: 26°156 —16 44 21-54 —0:004 —2°57 R | 696 Nov. 08 - 43273 23 38 26-077 —16 44 21-92 | 697 Nov. 18-40361 23 38 13-266 —15 54 09-30 —0:009 -—2:70 R | 698 Nov. 18-40361 23 38 13-269 —15 54 09-06 7 Iris 1965 U.T. 699 May 31-77350 21 10 09-520 —12 Ol 41-36 +0:008 —3-26 W 700 May 31-77350 21 10 09-508 —12 Ol 40-44 701 June 09- 74388 21 13 00-438 —ll 18 02-17 —0:014 —3:36 R 702 June 09- 74388 21 13 00-398 —ll 18 01-82 703 June 15:-74716 21 13 46-520 —10 52 35-97 +0:046 —3:42 §S 704 June 15: 74716 21 13 46-523 —10 52 35-88 705 July 05: 69467 21 O29 07-554 —09 56 07-96 +0:0638 —3:°55 S 706 July 05 - 69467 21 09 07-557 —09 56 08:38 707 July 22-61245 20 56 48-540 —09 48 04:06 —0:022 —3-57 R 708 July 22-61245 20 56 48-544 —09 48 04-45 709 July 26- 60502 20 53 02-404 —09 51 29-90 —0:003 —3:°56 §S 710 July 26- 60502 20 53 02-348 —09 51 30-48 711 August 09-55706 20 38 47-832 —10 16 24-92 —0:003 —3:50 R 712 August 09-55706 20 38 47-830 —10 16 24-88 713 August 17-55516 20 30 53-993 —10 36 50:44 +0:076 —3:46 S 714 August 17-55516 20 30 53:973 —10 36 49-40 715 August 23-52342 20 25 38-266 —10 53 21-80 +0:040 —3:42 W 716 August 23-&2342 20 25 38-264 —10 53 21-74 717 August 31-48326 20 19 55-716 —1ll 15 26-07 —0:005 —3:36 R 718 August 31-48326 20 19 55-668 —ll 15 24-90 719 Sept. 14- 43689 20 14 37-264 —ll 48 42-21 —0:019 —3-28 R 720 Sept. 14-43689 20 14 37-301 —ll 48 41-92 721 Sept. 23-41498 20 14 42-618 —12 03 32:90 —0:011 —3°25 W 722 Sept. 23-41498 20 14 42-606 —12 03 33-21 123 Oct. 06-39631 20 19 40:014 —12 12 25-12 +0:0383 —3-24 § 724 Oct. 06-39631 20 19 39-982 —12 12 24-66 725 Oct. 12-38625 20 23 43-859 —12 10 41-18 +0:042 —3-:23 R 726 Oct. 12-38625 20 23 43-883 —12 10 40:94 11 Parthenope 1965 U.T. (OA March 01-72257 14 04 56-372 —06 12 52-50 —0:007 —4:05 W 728 March 01-72257 14 04 56-334 —06 12 52-88 729 March 10-70067 14 03 43-932 —05 40 53-80 +0:004 —4:14 R 730 March 10-70067 14 03 43-922 —05 40 54-35 731 March 23-66026 13> 58132573 —04 37 15-03 +0:001 —4:26 W 732 March 23-66026 13 58 13-566 —04 37 14:64 733 April 20: 56286 13 35 44-018 —Ol 52 21-52 —0:016 —4:62 R 734 April 20: 56286 13 35 44-023 —O1 52 21-38 735 April 27-55678 13 29 34-403 —0O1 17 40:44 +0:038 —4:-70 §S 736 April 27- 55678 13 29 34-364 —0O1 17 40-56 737 May 04: 52854 137 1237 56-701 —00 50 02-96 +0:021 —4:76 W 738 May 04. 52854 13 23 56-722 —00 50 02-84 7139 May 17-47233 13 15 52-037 —00 21 37-32 —0:025 —4:82 R 740 May 17-47233 13 15 52-030 —00 21 37-90 741 May 26-44784 13 12 34-512 —00 20 37-84 —0:018 —4°82 R 742 May 26- 44784 13 12 34-506 —00 20 37-88 743 June 01-43211 13 Il 32-575 —00 28 21-44 —0:014 —4:80 R 744 June 01-43211 13 1l 32-573 —00 28 21-86 PRECISE OBSERVATIONS OF MINOR PLANETS DURING 1965 AND 1966 67 TABLE I—continued R.A. Dec. Parallax No. (1950-0) (1950-0) Factors h m Ss o 4 a Ss v 11 Parthenope—continued 745 July 01-37447 13 19 53-248 —02 32 09-88 +0:043 —4-54 W 746 July 01°-37447 13 19 53-216 —02 32 10°34 747 July 15-34153 13. 30 24-600 —04 06 11-70 +0:037 —4:33 R 748 July 15-34153 13 30 24-602 —04 06 11-68 2 Pallas 1966 U.T. 749 July 26: 78892 Ol 20 47-134 +02 14 00-04 —0:010 —5-17 W 750 July 26- 78892 01 20 47-170 +02 13 59-64 751 August 04-77095 Ol 25 08-183 +01 09 04:57 +0:001 —5:03 R 752 August 04-77095 Ol 25 08-179 +01 09 04:22 753 August 08-76919 Ol 26 37:386 +00 34 32-70 +0:026 —4:96 §S 754 August 08-76919 Ol 26 37-401 +00 34 33-44 755 August 22-71912 Ol 29 20-961 —Ol 54 21-41 —0:012 —4:64 R 756 August 22-71912 Ol 29 20-962 —0Ol 54 21-30 Tia Sepe. 06-67632 Ol 27 38-178 —05 20 56-44 —0:018 —4:18 § 758 Sept. 06: 67632 Ol 27 38-204 —05 20 56:24 759 Sept. 19-64275 01 22 12-690 —08 49 13-54 0-004 307k 760 Sept. 19: 64275 Ol 22 12-656 —08 49 14-04 761 Sept. 27-62315 Ol 17 218-596 —ll 02 31-94 +0:017 —3-40 S 762 Sept. 27:°62315 Ol 17 18-554 —ll 02 32-70 763 Oct. 10-58137 Ol O7 42-524 —14 29 54-70 +0:018 —2-90 R 764 Oct. 10:58137 Ol O7 42-546 —]14 29 54-20 765 Oct. 20-5420] 00 59 54-634 —16 48 06-90 +0:020 —2:57 S 766 Oct. 20-54901 00 59 54-630 —16 48 06-88 767 Nov. 15:46577 00 44 41-138 —20 27 31-26 +0:014 —2:03 W 768 Nov. 15:46577 00 44 41-038 —20 27 31:18 11 Parthenope 1966 U.T. 769 July 11-77308 00 O06 26-645 —02 35 02-69 —0:026 —4:-55 R 770 July 11-77308 00 06 26-633 —02 35 02-28 771 July 26- 75282 00 15 10:°002 —02 28 51-42 +0:019 —4:57 W ihe July 26- 75282 00 15 10-068 —02 28 51-52 713 August 08-70256 00 17 58-810 —02 58 07:42 —0:031 —4:-50 S 774 August 08-70256 00 17 58-776 —02 58 08-34 775 August 22-67774 00 15 34-006 —04 05 42-02 +0:014 —4:°35 R 776 August 22-67774 00 15 33:978 —04 05 42-37 lely| Sept. 06 - 62436 00 O7 13-322 —05 48 47-84 —0:007 —4-12 S 778 Sept. 06: 62436 00 O7 13:°304 —05 48 47-80 779 Sept. 19-58118 23 56 51-206 —07 25 32-32 —0:008 —3-:90 R 780 Sept. 19-58118 23 56 51-202 —O7 25 31-94 781 Oct. 20-49010 23 35 42-000 —09 47 15-37 +0:017 —3-57 S 782 Oct. 20:-49010 23 35 42-024 —09 47 15:53 783 Nov. 15-41903 23 35 32-236 —09 O7 54-54 +0:017 —3:67 W 784 Nov. 15-41903 23 35 32-250 —09 O7 54-60 40 Harmonia 1966 U.T. 785 June 01-75792 20 55 37-249 —18 52 43-86 —0-°003 -—-2-25 R 786 June 01-75792 20 55 37-250 —18 52 44-20 787 June 16:71747 20 58 50-555 —19 20 23-00 —0:008 -—2-19 W 788 June 16:71747 20 58 50:572 —19 20 24-46 789 June 20-70488 20 58 31-138 —19 33 29-28 —0:0138 -—2-15 R 790 June 20- 70488 20 58 31-156 —19 33 29°53 791 June 27° 703877 20 56 42-562 —20 02 06-82 +0:050 —2-10 S 792 June 27°70377 20 56 42-546 —20 02 07-52 793 July 11-64754 20 48 38-174 —21 16 42-60 +0:009 —1:90 R 794 July 11-64754 20 48 38-155 —21 16 42-80 795 July 25-60917 20 35 56-077 —22 42 06-76 +0:038 —1-69 W 796 July 25-60917 20 35 56-082 —22 42 06-94 797 August 04-:57681 20 25 48-461 —23 38 19-98 +0:045 —1-55 R 798 August 04-57681 20 25 48-405 —23 38 21-14 799 August 08-55057 20 21 53-946 —23 57 54-45 +0:003 —1:49 S 800 August 08-55057 20 21 54-014 —23 57 54-46 68 W. H. ROBERTSON TABLE I—continued R.A. Dec. Parallax No. (1950-0) (1950-0) Factors m Ss ° c u s a | 40 Harmonia—continued 801 August 22-50127 20 10 24-188 —24 48 48-18 —0:008 —1:36 R 802 August 22-50127 20 10 24-220 —24 48 48-80 803 Sept. 01-46349 20 05 30:798 —25 06 44-04 —0:032 —1:32 R 804 Sept. 01-46349 20 05 30-890 —25 06 43-60 805 Sept. 12-44629 20 04 O1:830 —25 09 43-77 +0:015 —1:31 §S 806 Sept. 12-44629 20 04 O1-816 —25 09 43-38 807 Sept. 27-41151 20 O08 39-607 —24 49 02-48 +0:025 —1-36 W 808 Sept. 27-41151 20 O08 39-651 —24 49 O1-71 809 Oct. 05-39518 20 I3 57-798 —24 27 41-03 +0:031 —1:42 §S 810 Oct. 05:-39518 20 13 57-769 —24 27 40-40 8ll Oct. 11-40051 20 19 04-664 —24 07 15-64 +0:092 —1-51 W 812 Oct. 11-40051 20 19 04-732 —24 07 15-08 TABLE II No. Star Depend. R.A Dec No. Star Depend. R.A Dec 673 57 0- 288671 24-715 54:61 687 40 0-458238 56-594 41-73 76 0-439788 29-846 48-79 51 0- 258996 57-735 57:64 85 0- 271542 06-060 53°59 70 0- 282766 21-412 05-86 674 56 0- 212724 48-904 37-40 688 36 0: 249963 28-508 30-02 75 0-496203 48-737 11-04 0-441758 41-057 32-86 87 0- 291073 15-907 10:66 0-308279 26-772 28-22 675 81 0-415412 38-547 38°74 689 0-381833 53-792 56-52 97 0- 288122 33-164 34-36 0- 292764 34-842 16-69 98 0- 296466 41-493 44°54 51 0-325403 57-735 57-64 676 715 0: 194240 48-736 11-04 690 0: 235842 34-183 41-86 90 0:-516692 55-930 33°84 0-443218 47-064 34-80 107 0: 289068 35-335 48-70 0-320940 34-600 12-20 677 76 0: 272952 29-846 48-79 691 8770 0:419940 37-818 15:94 93 0-430556 58-764 57-00 8787 0- 239914 22-724 29-32 108 0- 296491 51-685 28-78 9948 0-340145 51-274 16°47 678 81 0-308198 38-547 38-74 692 9930 0: 363094 58-852 43-30 98 0-467330 41-493 44-54 8778 0:439031 10-572 27°15 107 0: 224471 35-335 48-70 8797 0: 197875 01-084 44-88 679 90 0: 272273 55-931 33°85 693 9898 0-304466 05-398 58:18 107 0:315274 35-335 48-70 8742 0- 281934 34-721 13-46 108 0-412454 51-685 28-78 8770 0-413599 37-819 15-94 680 88 0: 233834 38-319 28-26 694 8735 0-374544 18-335 00-97 97 0-417666 33-164 34:37 8778 0- 221586 10-573 27-16 116 0: 348500 19-924 08-96 9912 0: 403869 56-619 13-41 681 90 0:397071 55-933 33°85 695 8720 0-500423 08-601 02-78 111 0: 253868 30-927 31:91 8722 0-288221 38-422 53°42 115 0-349061 18-492 20-18 8742 0: 211356 34-720 13-46 682 88 0- 267248 38-319 28-26 696 8713 0-327801 48-814 19-76 107 0- 230272 35-335 48-70 8725 0-321552 59-438 04-88 113 0- 502480 51-497 01-77 8735 0-350647 18-335 00-97 683 99 0:401848 48-146 57:96 697 8705 0-309191 21-445 58°75 102 0- 284358 27-046 06-93 8726 0-346488 20-483 04-36 118 0:-313794 01-595 52-26 8737 0:-344320 26-658 25-53 684 88 0-372826 38-319 28-26 698 8715 0-383203 02-330 29-62 106 0: 266076 18-166 58-59 8728 0: 430345 30-315 39°37 122 0:361099 42-841 39-65 8739 0- 186452 48-555 38-31 685 89 0- 236224 39-885 33°95 699 7500 0: 340555 51-060 42-30 96 0360646 32°399 08-90 7525 0- 432522 11-349 41-05 128 0-403130 12-277 15-29 7536 0: 226923 09-370 03-14 686 86 0: 290580 14-541 31-98 700 7515 0: 490044 37-361 16-84 110 0-394862 32-930 16-51 7520 0- 279356 19-281 31-67 131 0:314558 44-116 11-46 7523 0- 230600 05-977 18-57 PRECISE OBSERVATIONS OF MINOR PLANETS DURING 1965 AND 1966 TABLE I[I—continued No. Star Depend. RAG Dec. 701 7519 0-318395 03-651 02-49 7528 0- 295928 28-657 56-35 7556 0-385677 36-486 13-16 702 7523 0-346615 05-977 18-57 7533 0-318298 43-978 30-90 7547 0-335087 13-907 30-81 703 7519 0-403124 03-651 02-49 7545 0-313397 38-430 09-68 7567 0- 283478 06-580 44-99 704 7520 0- 222994 19-281 31-67 7522 0-359816 58-180 07-74 7566 0-417190 03-022 59-65 705 7508 0-330046 02-268 50-43 7511 0-360076 32-113 57-68 7522 0- 309878 58-180 07-74 706 7494 0- 237168 30-069 16-43 7531 0-317514 41-847 24-04 7600 0-445318 30-890 36-80 707 7413 0-300648 11-355 51-63 7451 0-383288 38-913 24-02 7517 0-316064 51-297 00-73 708 7415 0-332572 11-267 39-82 7458 0: 283278 05-022 20-60 7525 0-384151 39-975 25°18 709 7391 0- 299062 02-225 16-31 7413 0-318054 11-355 51-63 7511 0- 382884 25-593 10-73 710 7388 0-429242 17-865 19-72 7423 0- 248068 24-334 25-87 7427 0-322690 12-162 37°59 711 7307 0- 305582 09-594 11-39 7322 0-314690 01-833 27-70 7331 0-379718 43-706 22-90 LZ 7298 0-378390 48-803 30-50 7328 0- 241060 32-694 22-04 7340 0-380550 38-921 31-28 713 7248 0-329132 21-235 14-68 7261 0-362110 37-420 13-20 7287 0- 308758 56-162 20-83 714 7237 0-303586 52-348 10-28 7271 0-379685 46-339 18-91 7286 0-316729 43-001 42-05 715 7210 0-271482 25-797 16-23 7222 0- 429626 08-544 52-03 7248 0- 298892 21-232 14-68 716 7205 0- 266947 41-466 36-48 7225 0: 439554 34-766 46-20 7249 0- 293499 24-359 34-49 717 7162 0-322819 14-760 38-01 7192 0- 233623 07-145 42-19 7193 0- 443558 15-209 24-87 718 7163 0-356175 17-408 10-42 7183 0-307879 57-691 42-71 7205 0-335946 41-469 36-48 719 7124 0-343598 02-409 27-43 7147 0-329152 11-455 03-37 7177 0-327250 48-729 20-32 720 7130 0- 306596 03-893 35-06 7150 0-430792 50-663 23-95 7162 0: 262612 14-761 38-01 721 7137 0-452545 04-986 11-16 7150 0- 276510 50-663 23-95 7163 0- 270944 17-408 10-42 722 7124 0-351584 02-409 27-43 7156 0-331228 10-258 48-20 7162 0-317188 14-761 38-01 No. 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 Star 7177 7180 7192 7158 7175 7212 7180 7210 7236 7192 7208 7228 4998 5022 5038 5013 5040 5021 5016 5022 5024 5006 5023 5038 4981 5000 5001 4987 4996 5019 3609 3615 3624 3605 3610 3626 3589 3593 3597 3583 3595 3606 3569 3580 3586 3572 3577 3593 3557 3559 3568 3552 3563 3566 3541 3557 3559 3546 3553 3563 3538 3553 3563 3541 3557 3559 Depend. eoeocoocdocoocqcoocoodocococ@e@cocecocqcooqooqooqooqooqooqooooqocooooooqooooooocococoooooococoqooooooooqoooqooqoooocmhnee -441044 -337951 - 221006 - 331580 - 329882 - 338538 - 216517 -456632 326850 - 300872 - 232734 -466394 - 378780 - 218333 -402887 -439532 - 237424 - 323043 - 375200 - 259276 > 365523 - 359952 -394371 - 245677 -176882 - 334100 -489017 - 263308 -558879 -177813 - 296558 361347 - 342096 -339118 - 354316 - 306566 - 243036 -432365 -324598 -404154 - 283376 -312470 -387916 - 336146 - 275938 - 291323 - 507938 - 200739 -405513 » 232266 - 362220 - 296998 -415542 - 287460 -172808 -555700 - 271491 - 241704 - 505264 - 253032 -324084 -401994 - 273922 -392147 - 343300 - 264553 R.A. 48- 49- O7- oo: 42- 32° 49- 25° 44 O7- - 269 48- 20: 05- 50- 35: 54: 18- 00- 05- 14- Zs 15- 50- 08- 06- 05: 22: 14- 25: 59- -476 38- 13- 09- 19- 08- 10- 10- 21- 02- 18- 46- 55> 12s 40- 10- 10- 49 - 52° 54: 32° 24: 34: 10- 49- 52: 33° 37° 24- 20- 37: 24: 10- 49- 52: 57 21 729 978 148 763 560 301 979 797 269 147 160 168 152 953 340 330 933 801 152 807 182 O11 953 747 661 749 229 252 147 675 285 660 629 476 702 753 050 643 114 455 185 463 960 052 ae 753 027 858 873 O77 272 026 555 027 858 918 132 271 383 132 271 555 027 858 Dec. 20: 33° 42- 41- 59- 52: 33° 16- 32° 42° 03- 45- 09- 46- 27° 41- 19: 26: 24- 46- 37: 14- 33° ya 7 -08 27 33° 31- 35> 10- 47- 42: 13- O7- 58: -97 21 00- 06- 55° O7- 44- ras JC 35° 13: 06- 21- 49- 40- 55° 33° 16- 04- 27° 23° 35° 47- 33> 16- 46- 39° 23° 16- 39: 23° “41 47 33° 16- 32 79 18 20 65 21 79 23 28 18 20 95 12 96 25 68 717 70 50 96 03 56 91 25 04 19 65 84 67 52 19 21 26 76 74 42 29 60 56 57 94 09 42 60 15 42 55 27 26 19 89 36 41 55 27 44. 99 90 06 99 90 55 27 69 <0 No é A. Dec. No. Star A. t 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 Star 4815 4844 3574 3561 3576 4833 4864 4879 4888 4861 4875 4890 365 380 388 360 369 399 262 278 406 261 285 399 268 275 294 263 287 288 333 362 286 277 346 368 300 337 347 331 360 298 277 296 297 276 307 295 257 272 281 254 265 291 273 289 291 268 293 296 249 258 261 243 259 262 Depend. SoOSoSCC OCC OO OS OCC COC OSC SSO OCC OS OOO SSS SO SOS OS SO SOS SS SSSSSSoSSSSSososoSoosoSoSsososooesoses -331268 » 245879 *422853 - 364569 -375163 - 260268 -343478 -355560 -300961 -306515 - 229185 -464300 - 212358 - 266716 -420926 -285815 - 293594 °420591 - 199146 - 523386 - 277469 - 188580 -344867 -466553 265520 315690 418790 274238 -481893 - 243869 - 232202 -425794 - 342004 -309374 -378663 -311963 - 265862 -381474 - 352664 -318760 -317306 -363935 -473978 - 214348 -311674 -400778 - 279398 *319824 215010 -481521 - 303469 -303772 - 255728 -440500 -403210 - 194504 -402286 -383166 -311550 -305284 - 295762 - 144476 -559762 - 238450 - 325862 -435688 R.A 46: 26: 49- 20: 39° 52: 09- 33° 48- O7- 40- 56- 45: 02: 05- 19: 43° 33° 52: 11 11 521 883 343 483 135 081 494 236 669 402 664 419 172 569 514 969 488 166 060 -978 -654 40- 21: 33° 45- 50: 25° 24: 34: 37: 23° 13: 27° 06- 43° 19- 30° 55° 15- kee 08- 45- 08- 58: 58: 54: 41- 33° 39: 22: 06- 18- 28: O7- Mabe 22: 25: 57: 36- 29- 38: 00- 04- 57: 53° 20: 392 968 166 644 014 250 258 650 943 090 905 193 846 350 133 192 221 849 234 768 503 676 244 584 713 068 520 176 077 045 585 361 730 149 816 835 012 351 494 850 912 731 789 465 123 W. H. ROBERTSON TABLE II—continued 03-93 767 172 09-30 195 13-79 214 08-38 768 183 55°90 199 56-46 206 00-04 769 5 20-34 24 43-24 41 53°76 770 13 32-09 1h 05-90 31 32:21 771 42 28°15 61 10-88 65 08°75 772 46 11-23 51 12-49 72 22-23 773 54 12-07 58 28-97 cy 54°98 774 59 07-80 65 12-49 72 04-30 775 46 04-92 52 53°27 73 31-22 776 39 03-50 54 36-84 74 56:30 117 8 19-77 21 45-38 25 45-34 778 18 24-59 14 48-09 32 33°13 7179 8428 46-22 8446 58-94 8458 38°45 780 8433 24-79 8448 08-43 8449 08-49 781 8229 12-24 8240 21-63 8363 48-88 782 8217 58°46 8244 20-41 8372 48-87 783 8357 13-51 8372 35-36 8238 25-46 784 8348 13-82 8375 56:58 8229 11-64 785 8973 33°71 8998 11-66 9009 45-41 786 8965 30°61 8996 58-46 9015 32-65 787 8984 33°88 9027 45-56 9028 16-04 788 8995 40-49 9015 07°15 9033 Depend. 236152 437828 326020 342006 225501 432493 -426172 - 340767 - 233061 -361256 - 228162 -410582 -440274 » 266837 - 292889 -313418 -474386 - 212196 » 237824 °311521 -450655 400268 255918 343814 273216 -471240 255544 » 244751 *445947 -309302 -379268 -317136 -303596 » 257548 462011 - 280441 » 255228 -416084 - 328688 -344514 -428618 - 226868 - 213300 -393014 - 393685 - 350268 *328284 -321448 -459250 - 246465 » 294284 - 364183 -412682 - 223135 - 309006 - 293269 -397724 - 262362 - 530258 - 207380 - 238214 - 530760 - 231025 - 339502 - 212580 -44.7918 52: No. 789 790 791 792 793 794 795 796 797 798 799 800 PRECISE OBSERVATIONS OF MINOR PLANETS DURING 1965 AND 1966 Star 9006 9009 9029 8985 9014 9033 8991 9006 9007 8979 9020 8996 8921 8945 8961 8929 8953 14462 14314 14324 14333 14299 14320 14353 14191 14197 14240 14178 14212 14250 14141 14149 14198 14127 14160 14181 Depend. SEO) SOO. Yoo a SS SSI OOOO SO OOOO SS 2 OO Ooo Sooo oS - 355428 - 208444 -436128 -208114 -493362 * 298494 » 221354 - 269401 -509245 - 290184 - 364240 -345576 -354800 - 280686 -364514 - 271220 391183 -337596 -241993 »549054 - 208953 - 256706 402438 340856 332444 -413958 » 253598 -500734 - 189479 - 309787 315832 -362454 321714 - 235625 -323483 -440892 R.A. 06: 17- 15- 44- 36- 00- O7- 06- - 264 58: 26- 08: 26- 55> 31- 22° 15: 34: -704 52: 00- 28° 11 07 31 11 294 052 633 303 400 205 691 294. 289 447 244 646 244 498 028 S79 185 959 361 023 -614 16: 45- 12: 10- 33° » 243 12- 50: 41- ie 24: 47 - 50: 747 177 190 719 667 086 086 314 451 023 514 998 TABLE IIl—continued Dec. -83 -87 -88 -69 -08 -96 “19 -83 -79 2 Thal -81 92 »24 -20 -38 -47 No. 801 802 803 804 805 806 807 808 809 810 811 812 Star 14035 14043 14067 14030 14054 14061 13980 14003 14023 13986 13989 14042 13961 13986 14023 13965 13989 14024 14020 14035 14042 14003 14043 14062 14062 14078 14106 14061 14080 14085 14124 14127 14152 14108 14141 14144 (Received 20 September 1967) Depend. Sooqooooeooqqoeqqcocooqooceoqoonooooooo°d 3 oO oo o:0' o' -397517 -329714 - 272769 -394132 - 237536 -3€8332 - 206309 -331430 -462261 - 268424 - 392890 - 338686 - 330856 -233771 -435372 - 304108 -370481 -325411 -314816 -348052 -337133 -424997 - 265498 - 309505 -498907 - 163746 -337348 - 258903 - 277580 -463517 - 350996 - 358920 - 290085 - 278068 - 365589 - 356343 R.A. 01 49 21 11 01 -471 -500 06- 16- 09- ll: 13- 21- 05- 56: 35: 47- 46- 56: 05- 55° 35: 27° 02: Ol- 47- -250 49- ll: 1l- 46- 40- -670 -894 54: 14- 24- 55: 40- 50: 10- 600 280 946 670 375 250 891 115 192 463 245 115 891 104 192 183 555 471 463 500 930 930 077 622 381 956 023 278 074 086 rise Dec. 42- 16- 15- 02: 02: 02- 04- O7- 27° 39> 16: Ue 09- 39: yy i 17: 16- 23° 54: 42- 19: O7- 16- 18- 18- -22 25: 02: -02 14- 19: 38: 37° 54- 25° 22: 51 37 27 13 30 63 17 15 76 79 76 26 23 74 24 26 76 15 23 13 92 27 74 79 13 66 69 76 15 13 13 76 61 75 87 73 71 uf : 4 ‘ A t — t 1 iv * Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 73-76, 1968 Minor Planets Observed at Sydney Observatory During 1967 W. H. ROBERTSON The following observations of minor planets were made _ photographically at Sydney Observatory with the 23 cm. lens. Observations were confined to those with southern declina- tions in the Ephemerides of Minor Planets published by the Institute of Theoretical Astronomy at Leningrad. On each plate two exposures, separated in declination by approximately 0-’5, were taken with an interval of about 20 minutes between them. The beginnings and endings of the exposures were automatically recorded on a chronograph by a contact on the shutter. Rectangular coordinates of both images of the minor planet and three reference stars were measured in direct and reversed positions of the plate on a long screw measuring machine. The usual three star dependence reducticn retaining to bring the star positions to the epoch of the plate. Each exposure was reduced separately in order to provide a check by comparing the difference between the two positions with the motion derived from the ephemeris. The tabulated results are means of the two positions at the average time. No correction has been applied for aberration, light time or parallax, but in Table I are given the factors which give the parallax correction when divided by the distance. The serial numbers follow on from those of a previous paper (Robertson, 1967). The observers named in Table II are W. H. Robertson (R), K. P. Sims (S) and H. W. Wood (W). The measurements were made by Miss R. Bull and Miss B. Frank, who have also assisted in the computation. second order terms in the differences of the Reference equatorial coordinates was used. Propet’ Ropertson, W. H., 1967. J. Roy. Soc. N.S.W., motions when they were available, were applied 100, 181. Sydney Observatory Papers No. 55. . TABLE I R.A. Dec. Parallax No. Planet Ul (1950-0) (1950-0) Factors h m S ° 4 we S wu 2190 8 1967 May 22-68325 17 37 22-44 —17 39 20-9 +0-11 —2-5 2191 55 1967 May 03-67628 16 33 26-29 —30 10 22-7 +0:07 —0°-6 2192 55 1967 May 31-56412 16 07 51-30 —30 13 45-0 0:00 —0-5 2193 58 1967 May 04-65342 16 12 05-82 —13 15 50:7 +0:04 —3-1 2194 58 1967 May 30-54226 15 50 34-56 —l1l1 51 10-6 —0:°04 —3:-4 2195 64 1967 May 01-68420 16 27 48-90 —23 38 23-2 +0:09 —1:-6 2196 64 1967 May 09-64940 16 21 40-84 —23 26 03-9 +0:06 —1-6 2197 70 1967 May 22-70670 18 10 42-31 —33 36 31-5 +0°-12 —O-1 2198 94 1967 Aug 02-51798 18 55 05-79 —33 37 48-9 +0:04 0-0 2199 95 1967 May 17-59552 14 50 42-01 —21 O07 56:7 +0:16 —2-0 2200 101 1967 May 22-65894 16 21 43-53 —38 32 24-9 +0:26 +0°3 2201 108 1967 Apr 19-55926 13 08 12-31 —10 54 06-9 +0:02 —3-4 2202 108 1967 Apr 27-52058 13 02 33-85 —10 26 24:6 —0:02 —3-5 2203 116 1967 Aug 08-55104 20 30 28-82 —23 50 23-6 —0:02 —1:°5 2204 116 1967 Aug 25-48564 20 17 37-69 —24 27 26-9 —0:05 —1-4 2205 127 1967 Aug 02-54821 19 51 52-67 —33 35 14-8 +0:01 —0-2 2206 128 1967 Aug 02-61363 21 46 32-67 —22 52 51-1 —0:04 —1-7 2207 128 1967 Aug 08-62726 21 41 40-72 —23 29 39-7 +0:07 —1-6 2208 145 1967 Jul 13-52998 18 21 12-69 —30 37 40-2 —0:03 —0°-5 2209 150 1967 Aug 08-52305 19 34 32-11 —18 16 08-3 +0°:02 —2:-3 2210 150 1967 Aug 15-48949 19 30 16-26 —18 30 37-8 —0:02 —2-3 2211 159 1967 Jul 31-66381 22 31 57°62 —1ll 16 28-7 0:00 —3-4 2212 159 1967 Aug 10-63080 22 26 15-09 —12 07 05-1 0:00 —3-3 74 W. H. ROBERTSON TABLE I—Continued R.A. Dec. Parallax No. Planet Use (1950-0) (1950-0) Factors h m s 2 if UL Ss u 2213 160 1967 May 01-65328 15 35 33-46 —23 20 03-2 +0:10 —1:6 2214 160 1967 May 31-52257 15 08 41-20 —22 07 48-3 0-00 —1:8 2215 163 1967 Apr 18-58100 13 53 29-74 —05 11 14-6 —0:02 —4:2 2216 209 1967 May 29-67668 18 32 09-66 —33 39 59-3 +0-03 0-0 2217 209 1967 Jul 11-51855 17 55 45-39 —34 06 52-4 —0:03 +0:-1 2218 211 1967 May 30-57062 16 23 21-91 —23 08 05-5 —0:02 —1-6 2219 237 1967 Aug 01-53770 19 28 11-29 —30 30 45-4 +0:02 —0:5 2220 266 1967 May 30-60734 17 12 08-28 —16 19 21-7 —0:01 —2-6 2221 292 1967 Jul 12-58314 18 53 58-54 —44 53 34-6 +0:08 +1:-7 2222 332 1967 Jul 12-54583 18 42 08:36 —27 32 55-0 —0:-03 —1-0 2223 334 1967 May 04-61568 14 57 07-68 —10 12 11-1 +0:09 —3:°5 2224 334 1967 May 17-54317 14 48 46-16 —09 37 35-8 —0:01 —3-6 2225 356 1967 Apr 27-54722 13 28 59-21 —16 41 04-6 +0-01 —2-6 2226 356 1967 May 04-53986 13 23 14-98 —16 14 50-4 +0:06 —2-6 2227 364 1967 Aug 08-59907 21 21 44-91 —21 17 17-9 +0:02 —1-9 2228 364 1967 Aug 31-49557 20 59 39-27 —23 43 53-1 —0:06 —1:6 2229 366 1967 Aug 02-61363 21 51 24-09 —21 19 24-1 —0:05 —1:9 2230 382 1967 May 31-66495 18 19 18-47 —31 59 17-7 +0:04 —0-3 2231 382 1967 Jul 12-5151) 17 43 38:35 —30 33 43-7 0-00 —0-5 2232 389 1967 Aug 03-60578 21 16 55-46 —08 16 44-0 +0:01 —3-8 2233 389 1967 Aug 29-47688 20 54 15-28 —09 10 15-4 —0:12 —3-7 2234 393 1967 Apr 19-55927 13 10 07-60 —ll 52 48-4 +0:02 —3:°3 2235 393 1967 Apr 27-52058 13 03 51-10 —10 23 49-2 —0:02 —3°5 2236 412 1967 Aug 02-64645 22 23 32-85 —23 22 25-9 —0:02 —1-°6 2237 425 1967 May 09-64940 16 18 41-68 —21 15 46-6 +0:06 —1-9 2238 431 1967 Apr 18-6164] 14 41 15-41 —12 58 22-8 —0:01 —3-1 2239 462 1967 May 31-60368 17 06 15-80 —20 21 40-2 0-00 —2-0 2240 478 1967 Apr 27-60037 14 00 58-48 —19 11 23-8 +0-11 —2:2 2241 478 1967 May 10-53710 13 51 52-04 —17 29 05-6 +0:04 —2-4 2242 481 1967 May 17-64145 16 52 16-71 —22 58 24-5 +0:03 —1-6 2243 486 1967 May 29-61683 17 13 23-10 —14 59 15-6 +0:01 —2°8 2244 503 1967 May 11-63088 16 36 47:81 —21 23 39-0 —0:02 —1-9 2245 506 1967 Apr 04-55386 11 45 20-76 —21 15 33-8 +0:06 —1-9 2246 506 1967 Apr 18-49950 11 35 18-68 —20 12 11-6 +0:03 —2-0 2247 519 1967 Apr 18-65326 15 21 10-83 —18 18 23-8 +0:02 —2:-3 2248 519 1967 May 09-57206 15 02 37-29 —18 14 34-2 —0:02 —2-3 2249 607 1967 Apr 04-63058 13 33 20-22 —26 36 58-1 +0:06 —1-1 2250 674 1967 Jul 10-69784 21 15 01-51 —33 55 06-4 +0:12 —0O-1 2251 674 1967 Aug 10-59686 20 48 38-05 —36 31 02:4 +0:13 +0°3 2252 686 1967 May 17-64145 16 53 20-23 —21 03 23-4 +0-03 —1-9 2253 701 1967 May 09-64940 16 14 30-10 —22 05 20-7 +0:-07 —1:8 2254 702 1967 Jul 11-65920 20 55 42-83 —08 35 10-7 +0:03 —3-7 2255 702 1967 Aug 02-57486 20 36 58-82 —07 31 08-5 —0:01 —3-9 2256 704 1967 Apr 27-57012 13 33 14-18 —33 33 06-4 +0-08 0-0 2257 704 1967 May 03-56238 13 28 30-62 —32 54 58-1 +0-:12 —0-2 2258 712 1967 Aug 03-53967 19 33 30-21 —02 20 49-2 +0:03 —4-6 2259 715 1967 Jul 13-63093 20 31 42-77 —40 35 51-9 +0:01 +1-0 2260 736 1967 Jul 13-55723 18 41 25-86 —18 28 33-2 +0:02 —2°3 2261 736 1967 Aug 01-50293 18 26 40:17 —19 56 36-1 +0:04 —2-1 2262 751 1967 Aug 01-61152 21 18 55-16 —37 50 01-2 +0:01 —0-6 2263 751 1967 Aug 29-50470 20 52 18-21 —40 30 06-4 —0:04 +1-0 2264 760 1967 May 04-57319 14 09 30-43 —33 09 40-9 +0:07 —0-1 2265 760 1967 May 11-52378 14 03 20-38 —32 43 55-5 —0:03 —0-l1 2266 762 1967 May 04-57319 14 13 13-89 —33 32 10-7 +0-06 0-0 2267 762 1967 May 11-52378 14 07 27°31 —32 57 12-1 —0-04 —0-1 2268 852 1967 Apr 17-64926 14 56 48-55 —26 09 29-2 +0:05 —1-2 2269 852 1967 May 03-59320 14 33 25-54 —28 50 19-9 +0:07 —0-8 2270 952 1967 Jul 05-65016 19 42 35-14 —37 27 44-4 +0°13 +0°5 2271 952 1967 Jul 13-59078 19 34 32-40 —37 52 08-7 +0:01 +0-6 2272 967 1967 Aug 10-66276 22 54 04-35 —18 13 47-9 +0:04 —2-4 2273 1021 1967 Aug 02-61363 21 56 42-19 —23 13 28-9 —0:06 —1-°6 2274 1021 1967 Aug 08-62726 21 52 25-95 —24 28 14-7 +0:05 —1-4 2275 1264 1967 May 17-59552 14 50 19-45 —20 22 08-8 +0°-16 —2-1 2276 1264 1967 May 30-51143 14 41 45-24 —17 05 26-9 +0:02 —2°5 2277 1278 1967 Oct 26-56594 02 03 13-28 —07 35 37-2 —0:02 —3-9 MINOR PLANETS OBSERVED AT SYDNEY OBSERVATORY DURING 1967 Yale Yale Yale Yale Yale Yale Yale Cape Cape Yale Cape Yale Yale Yale Yale Cape Yale Yale Cape Yale Yale Yale Yale Yale Yale Yale Cape Cape Yale Cape Yale SAO Yale Yale Yale Yale Yale Yale Yale Yale Cape Cape Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Yale Cape Cape Yale Yale Yale Yale Cape 12 13 13 ae 11 14 14 17 17 13 18 dd 16 14 14 17 14 14 17 12 12 11 iT 14 14 div 17 17 14 Li: 12 Comparison Stars I 6343, 6348, 6356 II 10373, 10387, 10401 II 10131, 10139, 10171 5624, 5639, 5645 5504, 5519, 5520 11470, 11492, 11511 11437, 11470, 11482 9744, 9791, 9798 10280, 10314, 10317 I 6177, 6178, 6191 8094, 8121, 8139 4712, 4714, 4728 4700, 4717, 11 4702 14256, 14263, 14293 14108, 14120, 14123 10822, 10834, 10872 14922, 14932, 14960 14896, 14904, 14922 9886, 9909, 9943 II 8377, 8393, 8426 II 8349, 8368, 8379 7956, 7971, 7974 7919, 7939, 7947 11040, 11069, 11077 10821, 10859, 13 I 6284 4967, 4979, 4981 10029, 10061, 10063 9589, 9611, 9633 11466, 11470, 11492 10614, 10623, 10657 I 6159, 6172, 6188 229363, 229380, 229429 II 12175, 12212, 12227 5243, 5251, 5260 5203, 5206, 5224 I 5094, 5106, 5108 I 5075, 5079, 5094 I 9158, 9177, 14 14749 14538, 14556, 14559 I 9333, 9351, 14 14980 9857, 9877, 9917 9425, 9454, 9456 7650, 7654, 7667 7488, 7502, 7525 4723, 4728, 4739 4700, 4717, 4702 15217, 15232, 15236 I 6742, 6751, 6759 5159, 5162, 5190 I 6972, 7013, 12 II 6996 II 5904, 5917, 5933 I 5198, 5222, 5228 I 11677, 11708, 11718 I 6170, 6173, 6204 I 6799, 6813, 6826 I 5127, 5153, 5156 II 5069, 5091, 5093 I 5641, 5664, 72 II 6371 I 5543, 5559, 12 II 6252 9963, 9987, 10015 11612, 11616, 11643 10778, 10801, 10807 6897, 6901, 6920 11387, 11421, 13 I 6733 7502, 7521, 7525 7347, 7364, 7385 6872, 6894, 6912 TABLE II SSSsesesSeSSeSo SSS SSSSoSososooosoosoososossosooosossoosoososoosososososossosososososoosesosososooscscso °39277 * 26494 -31589 - 39292 - 20523 - 16226 -31095 -21455 -27873 - 23653 -38750 -39605 -37761 °46544 - 25888 - 20035 -37417 -32145 -32471 > 29309 - 30425 -43090 34144 - 23909 -15901 - 21166 -30194 »38526 -38763 29236 33868 22151 30655 32814 31571 - 18583 -11412 * 27335 - 24600 -31406 17879 34350 20493 -27005 °44413 -09755 -35340 - 20187 38210 * 24844 * 27002 > 28685 -46579 36054 32082 45045 45961 °42391 -08889 - 26063 *37299 *37575 » 26713 - 11083 -17516 -26198 -34649 Dependences eooooeosooooSSeossosesooSssesosososoSSSososooSoSSSoSSSoSSCSSCSSOSCSOSOSOSSOOSSOOSSOOSOSSOOSSOSOSOSOSOS - 22939 - 36264 - 29303 39180 67554 39557 31087 49813 45009 -30117 -27414 - 26375 » 24573 -32048 °37725 -37720 - 28342 -49640 -33638 - 26307 - 26602 - 34030 -34005 -46014 - 29168 -37733 -31458 - 34578 *29581 °28571 - 25049 -33496 - 29764 19733 32183 - 29828 - 62360 -31342 -28361 -33619 50491 35613 52866 * 27545 -37526 47407 23358 35544 32212 53934 47064 37547 30945 24106 34492 17309 13117 * 23249 51020 -31110 33097 °35445 -38820 -31182 -65315 *44286 -29118 -37784 *37242 -39109 *21528 -11923 *44217 -37818 * 28732 -27118 46230 -33836 - 34020 -37666 - 21407 - 36387 °41245 *34241 -18215 33891 44384 42972 22880 -31851 -30077 - 54931 -41102 -38348 * 26897 - 31656 °42193 -41082 *44353 - 39582 °47453 36246 -51590 * 26228 °41323 -47039 - 34975 -31630 30038 26641 -45450 -18061 °42838 -41302 -44269 29578 * 21222 - 25933 33768 22476 39840 33426 37646 40922 - 34360 -40092 *42827 - 29604 - 26980 »34467 °57735 -17168 - 29516 - 36233 ADA BNNDON DDD DODO DAO DM MOSM NSD SO ORR IOs dss 75 W. H. ROBERTSON TABLE II—Continued No. Comparison Stars : Dependences 2257 Cape 17 6837, 6841, 6852 0°37159 0: 25930 0-36911 W 2258 Yale 17 6695, 6709, 6735 0-35861 0: 36492 0- 27648 R 2259 SAO 230266, 230283, 230298 0:21152 0: 54532 0- 24316 R 2260 Yale 12 II 7838, 7875, 7894 0-33090 0-48522 0- 18388 Kk 2261 Yale 12 II 7714, 7749, 13 I 7731 0:43179 0-04150 0-52671 R 2262 Cape 18 11008, 11012, 11039 0-31759 0:45509 0-22732 R 2263 SAO 230412, 230430, 230450 0- 18382 0- 25690 0-55927 R 2264 Capesl7 7 1257,. 7299, 1290 0-32469 0- 40690 0- 26841 WwW 2265 Cape 17 7171, 7199, 7214 0-41067 0: 20450 0:38483 R 2266 Cape 17 7290, 7306, 7338 0-50069 0- 20502 0- 29429 WwW 2267 Cape 17 7214, 7251, 7259 0- 30520 0-35971 0-33509 R 2268 Yale 14 10715, 10737, 10751 0- 20076 0:48607 0-31317 R 2269 Yale 13 II 9197, 9209, 9226 0-21982 0:52414 0: 25604 WwW 2270 Cape 18 10221, 10241, 10245 0-19687 0:37554 0:42759 WwW 2271 Cape 18 10142, 10195, 10196 0-38588 0: 20346 0- 41066 R 2272 Yale 12 II 9650, 9669, 9672 0: 28959 0: 24938 0-46103 S) 2273 Yale 14 10513, 10523, 10544 0- 19369 0-50437 0-30194 R 2274 Yale 14 14970, 14989, 14992 0: 29624 0: 29472 0- 40904 S 2275 Yale 13 I 6170, 6191, 12 II 6192 0-45831 0-19251 0-34918 S 2276 Yale 12 I 5436, 5450, 5452 0-39275 0-31241 0- 29484 R 2277 Yale 16 437, 442, 463 0-35380 0-44818 0- 19803 S (Received 11 March 1968) Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 77-91, 1968 Magnetic Studies of the Canobolas Mountains, Central Western New South Wales R. A. FACER* Department of Geology and Geophysics, Umiversity of Sydney, 2006 ApstTRAcT—Field and laboratory magnetic investigations have been carried out on rocks of the Mt. Canobolas volcanic complex, near Orange, Central Western New South Wales. The complex consists of acid to basic lavas and pyroclastics, with some intrusives, built up on Palaeozoic rocks. The field magnetic results correlate in style and trend with the anomalies shown in existing aeromagnetic maps of the surrounding region of Palaeozoic rocks, suggesting that they largely delineate the structure of these rocks beneath the volcanic pile. Detailed laboratory investigations of the petrology, mineralogy and magnetic properties of the basalts from near Orange indicated a definite correlation between these properties. The basalts could be divided into two rock-types, titanaugite olivine basalt and olivine basalt, the first type having a stable magnetization, the second type unstable magnetization. This study has shown the need for complementary petro- logical studies in rock magnetic investigations. Introduction The Canobolas Mountains form a cluster of moderately high mountains west and south-west of the City of Orange (see Figure 1). The maximum elevation is about 4,600 feet (or 1,425 m.), whereas the surrounding peneplain has a general level of 2,800 to 3,000 feet (900 to 1,000 m.). The stream valleys towards the centre of the mountains are youthful, while Orange itself is situated in a mature valley. This stream pattern reflects the relief in the mountains. The foot- hills are generally low and undulating, with little or no outcrop, and there is a considerable increase in relief towards the centre of the complex, where the slopes are very steep. Even on these steep slopes, however, the outcrop is not good, and this lack of readily- available fresh rock created difficulties in sampling for palaeomagnetic purposes. In brief, the igneous complex forming the Canobolas Mountains is an accumulation of alkaline lavas and basalts (with minor intrusions) of presumed Tertiary age—the order of eruption being acid to basic. This accumulation has been built up on folded and eroded Palaeozoic rocks which vary in age from Ordovician to Devonian. Little detailed work has been done on the complex itself. David (1890) described the Old Man Canobolas; Curran (1891) described some thin sections of rocks from just to the north of this peak ; and Sussmilch and Jensen (1909) carried out a brief reconnaissance of * Present address: Department of Geology, Wollongong University College, Wollongong, 2500. B the complex. The central portion was examined in some detail by Penrose (1948). Several authors have referred to the Canobolas complex, commenting mainly on the possible order of eruption. For example, Sussmilch (1933) considered that the Canobolas Mountains occur adjacent to (or along) a north-south scarp, and that this is an example of an implied causal relation between the alkaline rocks of Blayney ce) ime) - : ——E—E——— Scale mn Mites FIGURE 1l1—Locality map. Area studied is shown, with that portion described herein shaded. Geographic coordinates of Orange are: lat. 33°17’S., long. 149° 06’ E. Roads are shown by full lines, and railways by broken lines. 78 R.A, FACER eastern Australia and the north-south trend of the Eastern Tableland, formed by the (Pliocene) Kosciusko Uplift. This conclusion may be expanded slightly to say that the Canobolas Mountains are located at a small change in trend of the Palaeozoic rocks, this change forming a favourable locus for volcanic activity. Other references to the complex are mainly found as brief notes on the “ Tertiary igneous rocks overlying the older sediments, etc.”’. No definite age can be assigned to the complex, however, without the aid of radiometric dating. The only geological evidence available is in the presence of a diatomaceous earth deposit and “Cinnamomum ”’ leaf fossils occurring at the western edge of the area studied, near Black Mountain. Although no definite relationship with the volcanics was seen, this does indicate a Tertiary age (Crespin, 1949). LEGEND V Basalts, Andesites Agglomerates A gg | Trachy tes : Ph [‘Ancesite, Sediments” SCALE Kell 10) Miles ¢ (@) ; 2 Km. 3 Figure 2—Simplified geological map of the Canobolas Mountains—showing the extrusive rocks of the complex only. The grid is taken from the Orange Military map. The major traverses” are shown: MAGNETIC STUDIES OF THE CANOBOLAS MOUNTAINS 79 In the magnetic field survey, the intensity of the vertical component “ Z ”’ of the geomagnetic field was measured. The intensity measured is not a simple intensity, but rather a sum of more than one magnetic field. There is a field induced in the rock by the earth’s field, and a field “‘ fixed ”’ in the rock (a “‘ remanent magnet- ization’). It is only recently that this second field has been considered important in magnetic field studies (e.g. Hays and Scharon, 1963 ; Strangway, 1965). The two fields are added vectorially : j =e; y; J J; Total Remanent Induced For a detailed treatment of rock magnetism, reference should be made to Nagata (1961). In keeping with recent practice, the following standard abbreviations are used in this paper : NRM (natural remanent magnetization) ; TRM (thermoremanent magnetization) ; PTRM (partial thermoremanent magnetization) ; IRM (isothermal remanent magnetization); VRM (viscous remanent magnetization); and CRM (chemical remanent magnetization). Instruments and Methods The field instrument used was a McPhar M500A portable fluxgate magnetometer. The field technique consisted of taking readings every 0-25 mile (0-4 km.) along roads and tracks with some closer-spaced stations surveyed on foot. Each station value was normally the average of four readings taken over an area of several square feet in order to minimize the effect of local fluctuations of the field. The whole survey was tied to a Base Station, which was used as an arbitrary datum and also as a diurnal control station and to intermediate Base Points. The field measurements were reduced by correcting for diurnal variation and by smooth- ing of the profiles using a five-point running average, to damp short-wavelength variations of near-surface origin : | jee V.=-— Dd v, i 5 Ame U; where V,; is the smoothed value and v,; is the actual value, at the 2 point. A regional correction was not applied because the field near the Bureau of Mineral Resources geomagnetic station near Orange was disturbed (Parkinson and Curedale, 1960, and field notes taken during their survey). In any case, the regional correction would only be of the order of magnitude of one contour interval over the whole area. The results were plotted on a map and contoured. Rock samples were generally collected as the field survey was being carried out. Where possible, fresh oriented material was collected, the orientation procedure being simply to mark a strike and dip on to a face of the sample before its removal from the outcrop. Even where fresh outcrop was not available, unoriented samples were collected and the rock-type noted so as to provide correlation with the magnetic survey results. Specimens were prepared from: the samples by coring in the laboratory. Orientation of the specimens during storage was random. Since petrological and mineralogical cor- relation with magnetic properties was one of the main aims of the investigation, both thin sections and polished surfaces of the samples were made. In order to maintain maximum practicable control, the thin sections and polished surfaces were prepared from discs cut from the cores. The specimens were all measured using the astatic magnetometer housed in the Old Geclogy Building at the University of Sydney. This instrument was designed and constructed by Kazmi (1960). The methods of measurement and reduction of readings were essentially the same as those employed by Kazmi (1960) and Manwaring (1960). Tor a detailed summary of palaeomagnetic theory and practice reference should be made to Irving’s excellent book (1964). As yet, palaeomagnetic theory is incomplete, many assumptions being necessary and with considerable magnetic/petrological work of the type described by Wilson and Ade-Hall, and Cox, Doell and Dalrymple still necessary (e.g., Wilson, 1964 ; Ade-Hall, 19640 ; Cox, Doell and Dalrymple, 1964). Because magnetizations acquired subsequent: to a IRM (considering igneous rocks only here) are likely to cause a scattering in the direction of the NRM, it is necessary to remove these “secondary ’’’ magnetizations in order to determine the direction of magnetization at the time of consolidation. Two methods have been used in this present study—alternating field demagnetization and thermal demagnetiza- tion. The former method entails the application: of high alternating magnetic fields to the specimen to remove “ weak’”’ magnetizations, and the latter the application of high temper- atures in zero field and an inert atmcsphere (e.g., nitrogen gas) to prevent oxidation of the specimen. (The attainment of an inert atmos- phere is, however, difficult, because of trapped gases, and must be considered a_ potential limitation, especially when demagnetizing 80 R. A. FACER vesicular basalts.) Thermal demagnetization has the advantage of giving an indication of the Curie temperatures of the opaque minerals— because all PTRMs acquired below a certain temperature are removed by the application of that temperature. The A.F. method was carried out using apparatus designed by Chan (1963). A more extensive summary of the methods used may be found in Facer (1964). Field Results In all, 485 field stations were established along 90 miles (144 km.) over 65 square miles (166 sq. km.) of the survey. The results established a reasonable correlation between field results and surface geology in many cases— provided that these geological features were not too localized (e.g. a small dyke). A few very strong but localized anomalies were discovered, and were probably sites of lightning strikes. € Main Sites eee LEGEND A -Mt Canobolas m -Base Station fP-Quarry - Site CANQ @®-Site CAN46 375 TN =Traverse —Contour-Interval 19007 SCALE _FIGURE 3—Magnetic contour map showing the major traverses and the collection sites near Orange discussed here. Grid as for Figure 2. MAGNETIC STUDIES OF THE CANOBOLAS MOUNTAINS 81 Figure 3 is a summary magnetic contour map of the eastern portion of the area (the western edge having been covered in a reconnaissance fashion only). The contour interval of 100y was chosen to damp out minor fluctuations associated with strongly magnetic rocxs. At the centre is a broad ““ Low”’ anomaly, divided into three more-localized Lows. Of these, the two northern Lows are associated with the central volcanic vents of the Canobolas Mountains, including Mt. Canobolas, Towac Mountain and The Pinnacle. The third (local) Low is not connected with any previously recognized igneous centre. However, it is an area of considerable agglomerate outcrop, and it is possible that this Low represents a volcano buried by the agglomerates. The twe small Highs associated with this broad Low might indicate parasitic cones, or be simply normal “balancing anomalies ”’. The two intense anomalies (a High and a Low) in the north of the area are probably not caused by the surface geology alone, which is basaltic, andesitic and trachytic, but are more likely to be caused by the Palaeozoic rocks of prebable Ordovician age which outcrop on the northern edge of the area. The rocks strike approxi- mately N.-S., and are altered augite-rich rock and light-coloured shales or phyllites. South- ward extensions of these outcrops would place them under the main High and Low respectively. A quantitative evaluation of the remanent moment contribution at depth in the vector equation above is not possible. However, the only available outcrop provides useful clues to the possible contribution. This is likely to be considerable, especially should the “ andesite ”’ be a flow of considerable thickness, since the NRM moment of the augite-rich rock, which is probably an altered andesite, is about 1200 x 10-6 e.m.u./c.c. The phyllitic shales were unsatisfactory for preparation of specimens, but from their lithological appearance their moment is likely.to be no more than one- fundredth that of the “andesite ’’. To determine the depth to the body (or bodies) causing these anomalies, a profile was drawn perpendicular to the anomaly trend, and conventional depth-determination procedures carried out. These gave depths of the order of 2,000 to 4,000 feet (700 to 1,300m.), thus showing that the surface geology has not damped the influence of the Ordovician rocks to any apparent extent. North of the area studied the trend of the Palaeozoic rocks is N.—S., whereas to the south this trend is N.W.-S.E. This change in the regional structural trend is reflected by thé magnetic contours—and the location of thé volcanic centre over the change in regional trend gives further weight to the idea that the Canobolas Mountains are associated with crustal fractures, possibly opened during the Kosciusko Uplift (Sussmilch, 1933). The sharp magnetic High near the Base Station corresponds to the outcrops of columnar basalt in this corner of the area. Subsequent to the completion of this survey, the Bathurst 1 : 250,000 total field aeromagnetic map published by the Bureau of Mineral Resources became available. The more important features encountered in the ground survey are reflected in the air survey, although in the latter case the plane’s altitude has had a damping effect. The central triangulate Low is still apparent, as is the High associated with the basalt in the north-east. More importantly, the anomalies and trends which are here considered due to the Palaeozoic basement are quite noticeable on the aero- magnetic map. One important feature of the aeromagnetic map is that the contouring of readings is made less accurate by the rather wide flight-line spacing, which at times is more than two miles. This spacing is apparently controlled by the topographic relief of the Canobolas Mountains. In an area of such_ localized anomalies and steep gradients as were found here, this contouring uncertainty imposes limitations on interpretation of aeromagnetic results. Laboratory Results The magnetic remanence of a suite of samples from localities distributed over the area was measured. The studies were only of a recon- naissance nature, and since the directions of magnetization between most samples were found to be widely scattered the results are given in summary form only in the Appendix. The scatter of magnetizations appeared to be due to IRM and, in some cases, CRM components (Kobayashi, 1959). Only one group of laboratory results justifies detailed discussion here—those bearing upcn the relationship between muineralogy/petrclogy and magnetic properties of some basalt samples from a small quarry near Orange. The quarry referred to is situated adjacent to the railway line near the Base Station in the north-east corner of the area _ studied (Figure 3). A brief note on the petrology has already appeared (Wilshire, 1958). Wilshire considered that the quarry was situated in a 82 R.A. FACER single basalt flow. The basalt in this quarry and in the surrounding outcrops is quite remark- ably columnar (some columns being twisted), with columns up to 6 feet (2 m.) across—although there are patches which show little or no columnar development. Petrological Data Broadly speaking, the basalts can be described under two main names (titanaugite olivine basalt and olivine basalt). The modal com- positions are: Group 1 Group 2 Plagioclase 50% 30-35% ae ; (AN50- 60) (AN55— 60) Olivine + augite as 30-35% 15-20% Opaques 5-6% 15% Glass te 10% 30-35% (slightly dusty) (very dusty) Wilshire (1958) showed that the composition of the olivines fell in the range Fo,,4, and the augite had 2V of 48°-50°. In the glass of Group 2 the opaque granules are arranged in strings, forming a variolitic texture. Most of the opaque content of Group 2 is concentrated as equant anhedra of titanomagnetite, with a very little ilmenite (and pyrite and chalco- pyrite in CAN 9E). Group 1 opaques are present mainly as randomly-oriented, corroded (serrated) needles of ilmenite, with smaller equant anhedral to euhedral grains of magnetite and titanomagnetite. Weathering is moderate, but the alteration of the olivine (and glass) to red and green smectite-chlorite (and patotinite and goethite) noted by Wilshire (1958, pp. 132-133) is not well developed in the thin sections studied, although, in the case of CAN 9F, the formation cf magnetite from the olivine is more noticeable in the darker “ column rind ’’, and there appears to be a higher proportion of coloured alteration products in this rind. There is a slight difference in the weathering products (when developed) of the two -groups. In the first, the “ serpentine’? and clay/chlorite alteration products are dark green to brown (and red in the rind), whereas in the second there is development of a pale green product. In neither group is there any exsolution visible in the opaque grains—even up to magnifications of 1000. There is a little martization visible in CAN 9A. ‘The modal analyses for the cpaques are higher than the normative values calculated from Wilshire’s chemical analyses (see Table 1). It can be seen that the Group 1 and Wilshire’s unaltered basalt contain a similar percentage of opaques. The apparent higher percentage TABLE | Opaque Oxide Content of the Basalts Il- (Titan) tmenite | Mag- Total netite % % % Mode (this study), Group 1 ~l1 4-5 5-6 Mode (this study), Group 2 ila: 14-15 15 Norm (calculated from Wilshire, 1958) Norm (calculated from Wilshire, 1958) 3°04 LAG 4-20 3°19 7:89 11-08 Wilshire’s analyses (his Table 4B) are of “‘ olivine basalt ’’ and “ altered olivine basalt ’’ respectively. TABLE 2 Results of NRM Measurements True Direction of Number | Intensity NRM Sample of of NRM Number | Speci- | Jnx10-4 | Declina- Inclina- mens} 6-1. ul/c.ce tion tion De i n (Azimuth) CAN 9A 6 14-1 088 —43 CAN 9B 3 18-7 150 —42 CAN 9C 2 11-0 148 +17 CAN 9D 6 4-9] 001 —44 CAN 9E 2 3°33 187 — 56 CAN 9F 6 12-2 321 — 56 The tagnetic susceptibilities of all samples are of the order of 10-4 c.g.s. units. J,» D and I are all averages of the n specimens. Inclination is negative when ‘“‘normal’”’ in the Southern Hemisphere. of opaques in Group 2 is not simply an over- estimation from thin section study but also includes an estimate from polished surface study. Magnetic Data The magnetic results are listed in Tables 2 and 3. Table 2 contains the NRM results and Table 3 the results of the two demagnetization procedures. It can be seen in Table 2 that the directions of NRM are quite scattered—although in each case the intra-sample agreement was good, and deviated from the earth’s present field direction (D=11° E., [=—64°). However, the most striking feature of this Table is the close cor- relation between intensity /, of NRM and the petrography. Group 1, the (titan)augite olivine basalts all have an intensity in the range 10 to 20x10-*e.m.u./c.c., whereasAGreup, 2 (olivine basalts) have about one-third of this intensity (3 to 510-4 e.m.u./c.c.). This might MAGNETIC STUDIES OF THE CANOBOLAS MOUNTAINS 83 be a reflection of the opaque grain sizes in the two groups. The opaque grains in the first are mainly equant to elongate grains with sizes ranging from 0-1 to 0-5mm., whereas the second group has only a few grains in this range, most being only approximately 5 to 15u, which is sufficiently large for the formation of more than one domain (Stacey (1963) notes that magnetite grains can be multidomains in the range 0-1u to 1000p). Because of the scatter in directions, and in order to investigate the magnetic properties further, specimens from each sample were demagnetized by alternating field and thermal methods. These results are summarized in Table 3, and Figures 4 to 7. Figures 4 and 6 show the demagnetization curves for the two processes, the values having been normalized, and Figures 5 and 7 show the stereographic plots of direction relative to each sample. 0 2. Ficure 4 (a)—Alternating field dernagnetization curves for the basalts from site CAN 9. the peak demagnetizing field and /J/J, is the normalized value of intensity. -2 Hp ce x 10 TABLE 3 Stability of Magnetization Estimate of the Sample Estimate of Stability | Direction of the Number |————_,-______- TRM A.F Thermal D°T 1° CAN 9A Stable Mod. stable ne —53 CAN 9B Stable Mod. stable 152 — 40 CAN 9C Stable Mod. stable 143 +20 CAN 9D | Unstable Unstable c.180 |c. —5l1 CAN 9E | Unstable Unstable c.114 |e. —25 CAN 9F Stable Stable 015 —5l1 The stability is estimnated from the demagnetization characteristics. The direction is estirnated from both sets of de- magnetization results. CAN 9D and CAN 9E directions are rather doubtful because of their low intensity and their instability. | oO | 4 Hp» is GLOUpe lacs SAA); 9B (a), 9C (+) and 9F (<). 84 O 2 FIGURE 4 (b)—Alternating field demagnetization curves for the basalts from site CAN 9, the peak demagnetizing field and J/J, is the normalized value of intensity. -2 H, ce x 10 R. A. FACER 1Q 14 Hp is Group’ 2:2) SDA) iE The correlation between petrography and NRM noted above is once again obvious from the demagnetization results. The difference in magnetic properties is not due to simple differences in the extent of the weathering since care was taken in obtaining specimens away from the column rinds. If anything, weathering is very slightly more obvious in the stable Group 1 basalt. Group 1 demagnetization curves (Figure 4) are all moderately stable insofar as they show a steady and gradual decrease after the removal of only a small secondary component probably acquired during weathering. In addition, the directions of magnetization show little variation other than slight experimental errors. On the other hand, Group 2 results show little systematic behaviour. The demagnetiza- tion curves show a rapid decrease in J which is most likely due to VRM (and some IRM). However, the intensity then increases and decreases in a random fashion with each successive stage. In addition, the directions change rapidly—and randomly (Figure 5). Such anomalous behaviour is not an experi- mental coincidence, since each specimen of Group 2 was demagnetized at the same time as a specimen from Group 1. The thermal cleaning bas produced an even more ncticeable difference between the groups. Up to 400° C. Group 1 directions show only a slight change (Figure 7), although after this point most of the magnetization seems to have been removed, and the remainder is more scattered in direction; whereas the Group 2 basalts have random directions up to 400° C. Figure 6 shows that Group 1 probably contain ilmenite (Curie temperature 100° C. to 125° C.), titanomagnetite (with varying Curie temper- atures due apparently to slight variations in titanium content), and a small magnetite com- ponent (550°C. to 600°C.). These mineral MAGNETIC STUDIES OF THE CANOBOLAS MOUNTAINS (a) (b) FIGURE 5—Alternating field demagnetization plots (stereographic equal-angle projection) relative to each sample for the basalts from site CAN 9. KW is relative north. Circled symbols are N-seeking directions plotted on to the Upper Hemisphere, those points not circled being plotted on to the lower hemisphere. The points correspond to those in Figure 3. Symbols as in Figure 3. (a) Group 1. (6) Group 2. 85 86 Re A aC (a) J 4 n 5 1@) rd] —2 6 TG xo FIGURE 6 (a)—Thermal demagnetization curves for the basalts from site CAN 9. T is the demagnetizing temperature, otherwise the symbols are as in Figure 4. Group l. components were all detected during polished surface examination. The instability of Group 2 renders any positive estimate of the Curie temperature(s) impossible. As a check on these results, similar work was carried out on another basalt sample collected about 1-5 miles (2:4 km.) north of the quarry. This sample was collected from a trench about 4m. deep, dug for the laying of pipes, and the basalt appeared fresh despite a rather strong weathering rind about 2cm. thick along the joint faces. This basalt is a (titan)augite olivine basalt with ophitic to subophitic texture, slightly porphyritic, containing about 65°%% plagioclase (An,;; .)), 209% olivine and titan- augite (2V about 60°) in approximately equal proportions, 5°% opaques (titanomagnetite and ilmenite) and 10% “dusty” pinkish-brown glass, and is very similar to Group 1 basalts. Weathering has produced _ green/brown “serpentine ’’, clay and chlorite alteration products, mainly from the olivine and glass. As would be expected from the composition, the magnetic properties are similar to the Group 1 basalts (although the direction of magnetization does not agree). A _shelf-test conducted over several months suggested stability. Figure 8 shows the A.F. demagnetiza- tion curve and plot. It can be seen that a low coercive-force magnetic component (either due to the ilmenite or to the weathering) is first removed, and then there is a very gradual decrease in intensity indicating high stability. The stereographic plot also indicates this high stability. Discussion As can be seen from the present field results, subsurface structures can be readily detected if there is sufficient magnetic susceptibility and NRM contrast in the subsurface rocks, and provided some elementary precautions are taken in the survey. In particular, strong anomalies have been found over volcanic MAGNETIC STUDIES OF THE CANOBOLAS MOUNTAINS 87 °) FIGURE 6 (b)—Thermal demagnetization curves for the basalts from site CAN 9. demagnetizing temperature, otherwise the symbols are as in Figure 4. centres, and “ basement’’ trends under a volcanic veneer have been delineated by magnetic trends. This investigation has emphasized the close relationship between the petrological and mineralogical properties of rocks and _ their magnetic properties. Not only the _ initial composition and conditions of formation of the rock control these characteristics, but their subsequent history also seems to have an effect. In general, the relationships between the mineralogical composition and the magnetic properties is best investigated through the behaviour of the intensity and direction of magnetization during the demagnetization experiments, and this has provided good evidence here. The comparison cf these demagnetization results with observations on both thin sections and polished surfaces obtained in the present investigation evidences the need fer further detailed study of the ccrrelation problem. EecoL 6 T is the Group 2. A more detailed study of these basalts is necessary to understand their magnetic properties fully, and the techniques employed by Ade-Hall (1964a, 1964) and Wilson (1964) in their study of the Mull lavas in Scotland would be most useful. It is evident, for example, that there is a noticeable similarity in the weathering variations in the two areas. The Mull rocks with normal polarity showed development of pale green secondary silicates, and the reversed rocks contained dark green and brown “secondaries ”’. Althcugh no polarity difference has been found in this present study, the Group 1 basalts contained dark green and brown secondary silicates, whereas the second grcup contained pale green alteration products only, and so they fall into the same petrographic grouping as the Mull basalts. Further, the Mull reversed lavas exhibited stable moments and the normal lavas exhibited instability (Ade-Hall and Wilson, 1963), which is exactly as detected in the Orange 838 RAL PACER (a) FiGuRE 7—Thermal demagnetization plots up to 400° C. (stereographic equal-angle projection) relative to each specimen for the basalts fromm site CAN 9. The symbols are as in Figures 4 and 5, with the 100°C. steps as in Figure 5. (a) Group 1. (b) Group 2. MAGNETIC STUDIES OF THE CANOBOLAS MOUNTAINS (a) (b) Sze H, ce x10 FIGURE 8—Alternating field demagnetization results for CAN 46A. Symbols and explanation as in Figures 4 and 5 except that (-) is not to be confused with CAN 9D. (a) Plot. (b) Curve. The large decrease in J, up to 60 oersted is due to the high J, (100x10-¢ emu/cc). 89 90 R. A. FACER basalts. The correlation noted by Ade-Hall and Wilson with the opaque minerals was not established here, although ilmenite was only detected as a minor accessory in Group 2. While bearing in mind the bmitations of the sampling, the overall mean magnetic vector direction after partial demagnetization for the Canobolas Mountains volcanic rocks is: declination =132° T., inclination = —44° (assum- ing all inclinations to be negative). This corresponds to a palaeomagnetic pole position of latitude 15°N., longitude 105° E., which does not agree well with previously published Tertiary poles for Australia. (This disagreement is probably due to the probable large error in the mean magnetic vector above, which has a 95°% confidence circle of radius about 30°.) Concluding Comment The correlations between magnetic properties and petrology (etc.) that have been recorded are as yet insufficient for broad conclusions to be drawn—but they shcw the necessity of studying “rock magnetism’”’ together with ‘“ palaeomagnetism ”’. Future investigations into this problem, and increased understanding of the history of the geomagnetic field (especially the aspect of reversals) may in fact prove that the results reported here are simply coincidental, but this does not obviate the need for a petro- logical study as an important adjunct of palaeomagnetic investigations. Acknowledgements This study was mainly conducted in 1964 during candidature for an honours degree, and I would like to thank the Head of the Depart- ment, Professor C. E. Marshall, and my supervisor, Dr. A. A. Day, and other members of the staff of the Department of Geology and Geophysics, University of Sydney. Thanks are also due to K. M. Chan, R. J. Henderscn and E. P. Shelley for helpful discussions, and also Drs. R. L. Wilson, J. M. Ade-Hall and N. D. Watkins for their interest. Many citizens of Orange gave ready and valuable assistance, especially Mr. V. O’Connell. I am grateful to the District Forester at Bathurst and Mr. G. Windsor, Forester, N.S.W. State Forestry Commission, for access to the Cancbolas forests, and to the management of Orange Blue Metal Pty. Ltd. for permission to sample from the quarry and supplying drill core. Finally, I would like to express appreciation to Miss E. J. Ward for typing the manuscript and to Dr. Day for critically reading the manuscript and giving helpful comments. The work on sample CAN 46A was carried out during the tenure of a Commonwealth Post-Graduate Research Studentship. References ADE-HattL, J. M., 1964a. Electron probe microanalyser analyses of basaltic titanomagnetites and their significance to rock magnetism. Geophys. J. R. GSU SOG. 15, 3. Ul alae ADE-HaLL, J. M., 1964b. A correlation between remanent magnetism and petrological and chemical properties of Tertiary basalt lavas from Mull, Scotland. Geophys. J. R. astr. Soc., 8, 4, 403-423. ADE-HALL, J., AND Witson, R. L., 1963. Petrology and the natural rernanence of the Mull lavas. Nature, 198, 4881, 659-660. Cuan, K. M., 1963. Studies in rock magnetism. Unpublished M.Sc. thesis, University of Sydney. Cox, A., DoELL, R. R., AND DALRYMPLE, G. B., 1964. Reversals of the earth’s magnetic field. Science, 144, 3626, 1537-1543. CRESPIN, I., 1949. Diatomite. Min. Resour. Aust., Sumih. Rept. No.-12, 33° pp. CURRAN, J. 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JENNINGS 98 ‘SUOTJEALDXO OU} JO UOI}P9OT OF Z 9INSIT 99S DEPTH SEDIMENT SURFACE HEIGHT SEDIMENT DEPTH SURFACE HEIGHT v NOILVAVIX4 X14}OW Ul S¥907q }}DSDg y WV3Y1SHI018 ‘p pue gE SUIVOI]SYIOTG UW90M40q IPIAIP 9} JO puke | UTeeI{SyOOTq Jo o1njOnIWGS—F TAUNOIY ayu019 4+ + y0s0g a4 >490uN038 sjyuawb01y poom s]Osauiw 3}1u016 ‘QUI pud pa}}}OW Ayyonsn ‘ko,9, sydiowopnasd 4ods}aj pud oo1w *Zy40Nb jONpisay puos puo yaaos6 z340NH SNWAH woo} AyV!S $490)q })0S0g LX > SLISOd3G VWIDISd3adNS Lea 00z Sayd14W €EWV3AYNLSHIO1E 40 S a9Gla NO Y¥OL W034}S490)q a10g sar WW AY LS %-9018 | 4 NOILVAVIXS © L WWau1SH9078 X14}OW Ul S490)q })0S0g H1d30 IN3WIG3S LHOISH 39V38NS njzIs ul })0s0g SOME BLOCKSTREAMS OF TOOLONG RANGE KOSCIUSKO STATE PARK 99 blockstream 3) the basalt columns are tightly locked together at a depth of 60cm. or less with no weathered material between them, although parts of their tops are covered with a biscuit-coloured weathered rind (Plate 1). Situated between the basalt cap and the top of blockstream 1, section 8 has a surface layer of basalt blocks in a matrix grading from very dark brown crumbly loam above to yellow brown silt loam below. This 80cm. layer sharply overlies granitic materials, consisting chiefly of quartz gravel which has been transported in some degree. The topmost 63 cm. is organized into a soil profile with an organic-rich clay horizon ; below this at 157 to 178 cm. depth a silty layered horizcn contains woody fragments. Below 213 cm. the material has the character- istics of residual weathered granite. Section 8 belongs to an apron of rather uniform slope below the steep margin of the basalt cap, with no valley development in it and with no exposures of granite. Where bare blockstreams reach through it to the basalt cap above, they are notably narrower than further down but are at the level of the intervening ground (Figure 4c). This vegetated intervening ground commonly has basalt blocks projecting through the soil or else a very dark brown crumbly loam forms a surface layer. In section 4, between blockstreams 3 and 4, this completely stone-free layer is 60 cm. thick, and below is a layer with basalt blocks in a matrix similar to that already described for section 8. Underlying this is a thin layer of granitic material including small pieces of basalt above residual granite grus and mottled red clay. The top of this residual granitic material lies 25 m. below the top of the range, but it is thought that the basalt cap is considerably less than this in thickness. Below this zone the slopes carry valleys. These are well developed on the south-facing part of the western slopes with the bare block- streams sitting well down in them. The west- facing part is very much flatter and surveying and excavations were necessary to prove that the bare blockstreams occupy the lowest parts of these slopes (Figure 4b). The ridges and low swells between the blockstreams are largely covered with basalt blocks in a loam matrix, though granite gravel and granite outcrops appear over their lower parts. Bedrock granite is exposed most extensively, and to its greatest altitude, below the projecting south-west corner of the basalt cap; less basalt would have been shed on to this ridge from the retreating edges of the cap. Granite is exposed here only 30 m. below the crest of the range. Section 3, between blockstreams 3 and 4, has a similar sequence to that of section 4, though the block-free surface layer is rather thinner and the residual granitic material includes no heavy clay layers. Sections 1, 2 and 3, below the toe of block- stream 1, all have a surface layer of basalt blocks in a dark loamy matrix, overlying residual weathered granite (Plate 8). The surface layer belongs to a flat-topped tongue of valley fill below granite slopes on either side. Similar tongues project down valleys below some of the other blockstreams. The Origin of the Blockstreams The general character of the blockstreams, but especially their elongation downslope at a very low angle for such materials and the frequently sharply unconformable contact of the basaltic material with the decomposed granite place these features amongst the products of mass movements associated with periglacial conditions rather than amongst convergent forms found in tropical monsoonal areas such as Hong Kong (Wilhelmy, 1958). Two processes of mass movement associated with frost climate are relevant: a solifluction or congelifluction movement at a time when the interstices between the blocks, at present void, were filled by a fine matrix material such as 1s now present in the lowest layer only of the blockstreams, and a flow movement when these interstices were filled by ice, perhaps resulting from Balch ventilation between the blocks (Thompson, 1962). The first process of solifluction with a matrix seems undoubtedly to have taken place in some degree since the lowest layer of the blockstreams and the top of the underlying granitic material show a mixing of fragments of basalt with finer particles of granitic origin. This process may also account for the layers of basalt blocks with loam matrix on the ridges and slopes between the blockstreams and also in the valleys below their tces. These layers resemble very much periglacial solifluction mantles described from Tasmania (Nichols and Dimmock, 1965). Never- theless, the stone-free lcams overlying some parts of these layers are difficult to explain except by their subsequent emplacement either by surface wash or less probably by aeolian action. The possibility that at least some of the loam matrix in the block layers may be of similar origin cannot be excluded. On the other hand, narrow lanes and small patches of matrix-free blocks within areas where block layers with loam matrix are found at 100 the surface seem to be due to the washing out of fines subsequent to the emplacement of a solifluction mantle. That emplacement of blockstreams without sediment matrix, and so implicitly with inter- stitial ice as the lubricant, was important, seems to be borne out by various pieces of evidence from the Toolong Range blockstreams. Substantial proportions of certain blockstreams consist almost entirely of basalt columns ; these columns can be seen at the heads of certain streams to have been fed into them devoid of matrix from the bedrock and the summit excavation demonstrates the absence of weathered material between the columns still in situ. It seems that frost wedging has produced matrix-free block material in this way. The irregular pattern of pits on the surface of the blockstreams can also be explained by the melting of large bodies of the interstitial ice which permitted downhill movement at modest angles; if these pits had been due to fluvial removal of material from beneath the blockstreams, they would tend to occur in lines downslope. The bulging form of the toe and the flat or slightly hollowed area immediately above it on some of the blockstreams also favour this kind of origin. It seems unlikely that suffosion by wash processes would succeed in removing the fine material from the entire toe and leave such a bulging form. Sections 3 and 4 in the blockstream 1 profile, respectively immediately below and just above the toe, suggest an unconformable contact between the blockstream and the tongue of solifluction blocky earth below it. This lends further support to the hypothesis of movement of blocks with interstitial ice between them as responsible for some of the blockstreams (cf. Talent (1965) on Victorian blockstreams). Nevertheless the mechanism of deformation cannot be the same as that inferred by Wahrhaftig and Cox (1959) for Alaskan rock glaciers in which interstitial ice is regarded as essential. Employing a viscous flow model, they find strong similarity between the movement of the rock glaciers and that of true glaciers. The Toolong blockstreams are in fact too thin for shear stress at their base to reach the critical minimum value of about one bar for such movement (Wahrhaftig and Cox, 1959). Movement of the blockstreams is not con- tinuing at the present time. This is proved by the presence of lichens on the upper surfaces only of the blocks, by the occurrence of freshly frost-shattered blocks which exhibit no sign of N. CAINE AND J. N. JENNINGS movement, and by the lack of mixing of the lower two layers of blockstream 1. Moreover, plants are actively colonizing the margins and narrow parts of bare blockstreams (Plate 6) and organic debris is filling up the voids between the blocks. At many points a gradual lateral change from bare blocks with empty interstices to blocks completely enveloped in this way can be seen. Podocarpus lawrence: Hook f., Eucalyptus mphophila Maiden and Blakely, and Drimys lanceolata Baill. are the chief plants involved in this process of colonization and show no sign of the damage activity of the blockstream would cause. The vegetation around the blockstreams is, of course, responsible for the humic matrix of the second layer in vertical structure. The instability of occasional blocks, and their settling and rolling, do not deny the interpretation of the essential movement and emplacement of the blockstreams in terms of frost action in a more severe climatic phase than at present. However, not all the material present in the blockstreams need have been produced by periglacial weathering. It may be that the regularly shaped blocks of the upper parts of the streams are the result of frost wedging of the well-jointed basalt, whilst the more rounded smaller blocks lower down have been derived from earlier and different weathering processes. This has been suggested previously for material involved in the blockfields of Tasmania (Caine, 1966). The sudden change in shape and size of the blocks in at least one of the streams of the Toolong Range supports this double origin of the blocks themselves. Chronology and Climatic Change The wood from the quartz gravel in section 7 beneath blockstream 1 has been dated by radiocarbon at 35,200 Ble years B.P. (A.N.U. 76) and this provides a maximum age for the deposits above it. The interval between this date and the emplacement of the blockstream may not have been very long since the protective effect of the overlying material would be needed to maintain sand and gravel on this slope of 8°. A. B. Costin has investigated an analogous situation at Munyang in the Snowy Mountains not far to the south in which a humic soil is buried by solifluction fill of periglacial origin and has provided a date of 32,000 years B.P. It is likely that these periglacial mass movements, the most substantial of their kind in both areas, occurred during the cold phase responsible for cirque and valley glaciation SOME BLOCKSTREAMS OF TOOLONG RANGE KOSCIUSKO STATE PARK in the highest parts of the Snowy Mountains. Costin has dates which suggest that this glaciation occurred prior to 15—20,000 years B.P. It would seem, therefore, that the blockstreams can be allocated to a cold phase broadly equivalent to the final and maximum phase of the Weichsel-Wisconsin Glacial Period. The occurrence of the blockstreams, some of the evidence from which implies interstitial ice for their movement, indicates a mean annual temperature below 0° C. when they were active. The present mean annual temperature in the vicinity of the blockstreams is estimated from the lapse rate derived from the nearest climato- logical stations at 5-5:5°C. (41-42°F.). A lowering of 6° C. at least for the late Pleistocene may be compared with the 9°C. argued by Galloway (1965) for the area on other grounds. Since thick and long persistent snow cover would be inimical to their development, there may be as well a suggestion of lowered absolute precipitation, which has also been inferred for south-eastern Australia by Galloway. The wood of section 7 was originally obtained by auger, but subsequently a small excavation was made to get a larger sample. The shape and disposition of the wood were such that Dr. P. W. Williams and the one of us present (J.N.J.) accepted it without question during extraction as the remnant of a tree stool 7m situ. Unfortunately in view of subsequent findings no attempt was made to measure and draw up a section which would have demonstrated this. The wood has been identified by Dr. H. D. Ingle (pers. comm.) from a number of pieces as “in all probability Nothofagus of the southern group cf. N. cunninghamu’’. The humic gravel around the top of the stool was analysed for pollen and spores, and Dr. D. Walker’s report is included below. We concur with his inter- pretation that the spectrum most probably indicates at least a substantial proportion of vemanié Tertiary pollen. Lacustrine and fluvial sediments beneath Tertiary lava are common in the area; although no section or boring has demonstrated a similar occurrence beneath the Toolong Range lava capping, inference to this effect can be made with some confidence. The detrital gravel beneath the blockstream must have derived its content of Tertiary pollen from such a source. Thus the Nothofagus wood is the only reliable floristic indicator of conditions shortly preceding the emplacement of the blockstream. At least it proves that about 33,000 B.c. there was a period warmer than the succeeding cold period 101 in which the main periglacial, and probably the glacial, phenomena of the high mountains of southern New South Wales developed. Scarp Retreat An approximate calculation of the retreat of the basalt cap necessary to provide the material in the solifluction mantle and the blockstreams can be made. The thickness of the basalt cap may be put at 10 m., 1.e. slightly more than the greatest height of the steep marginal slope ; if at fault, this will be an under- estimate. The average thickness of slope material above the granitic layer in the eight holes excavated down to it is 1-15 m.; this is probably an overestimate when used as a measure for the whole slope, since the block- streams are thicker and over-represented in the sample. Reducing this 1-:15m. to 1m. to allow for porosity is also erring on the generous side for the volume of displaced basaltic material. With an area of 341,000m.2 from a basalt front of 1,040 m., the mobilized basalt regolith represents a retreat of the basalt margin of 33m. This retreat, almost certainly maximized in the estimation, lies within the width of the uniformly sloping apron below the steep marginal slope of the basalt residual. As has been mentioned in discussion above, it cannot be assumed that all the basaltic waste is the product of periglacial weathering, though it is largely of this origin. But since it has reached its present disposition by periglacial processes, and since the dated section 7 lies quite close to the residual basalt, it appears that virtually all this retreat has taken place since 35,000 B.P. Acknowledgements We are particularly grateful to Dr. H. D. Ingle of C.S.I.R.O. Forest Products Division for the wood identification ; to Dr. J. Lovering and Mr. H. Polach for the C-14 data from the A.N.U. Radiocarbon Laboratory ; to Dr. Walker and Mrs. J. A. Williams for the pollen analysis. Dr. A. Costin generously allowed us to refer to unpublished data and commented on the manuscript. Dr. P. W. Williams and Mr. A. Hodgkin gave valuable help in the field. References CAINE, N., 1966. The blockfields and associated landforms of north-eastern Tasmania. Ph.D. thesis, Australian National University, Canberra. CaRR, S. G., AND CosTINn, A. B., 1955. Pleistocene glaciation of the Victorian Alps. Proc. Linn. Soc. N.S.W., 80, 217-227. 102 DERRUAU, M., 1958. Précis de Géomorphologie, Paris. FEZER, F., 1953. Schuttmassen, Blockdecken und Talformen in nordlichen Schwarzwald. Gd6ttinger Geogrl. Abh., 14, 45-177. GaLitoway, R. W., 1963. Glaciation in the Snowy Mountains: A reappraisal. Proc. Linn. Soc. N.S.W., 88, 180-198. GaLLoway, R. W., 1965. Late Quaternary climates in Australia. J. Geol., 73, 603-618. JENNINGS, J. N., 1967. Some karst areas of Australia. Ch. 12, pp. 256-292. Landform Studies from Australia and New Guinea. Eds. J. N. Jennings and J. A. Mabbutt, Canberra. Nicuots, K. D., AND Dimmock, G. M., 1965. Soils, pp. 26-29, in Atlas of Tasmania, Ed. J. L. Davies, Hobart. Appendix 1 POLLEN ANALYSIS OF A SOIL FROM TOOLONG, N.S.W. D. WALKER Australian National Umiversity, Canberra The material was prepared for examination by a standard acetolysis method. A total of 533 pollen grains and 50 spores was examined, 500 of the former being allocated to living taxa and all of the latter being placed in morpho- logical groups. The pollen grains and spcres were in uniformly good condition after preparation. Of the taxa identified, Nothofagus subsect Bipartitae, Dacrydium, Mzucrocachrys, Phyllo- cladus and cf. Pinaceae do not grow on the Australian continent today. Excluding cf. Pinaceae, which is a common contaminant of preparations made in Canberra, this group, together with WNothofagus cf. cunninghamu, Casuarina and Podocarpus, forms an assemblage commonly recorded from Tertiary deposits. Indeed, after allowing for differences in the nomenclatural systems used, all these identi- fications can be matched with determinaticns from the supposed Early Tertiary (and certainly “ pre-basalt ’’) strata at New Chum Hill and other sites near Kiandra, about 40 km. distant from Toolong. Quintina, Eucrypma and Hypericum are genera represented in the modern Australian flora but also in highland forests of New Guinea, a region which they share with Nothofagus subsect. Bipartitae spp., Phyllo- cladus sp., Podocarpus spp., and, less character- istically, Dacrydium sp., and Casuarina sp. N. CAINE AND J. N. JENNINGS TALENT, J. A., 1965. Geomorphic forms and processes in the highlands of eastern Victoria. Proc. Roy. Soc. Victoria, 78, 119-135. THompson, W. F., 1962. Preliminary notes on the nature and distribution of rock glaciers relative to true glaciers and other effects of the climate on the ground in North America. Union Géod. Geophys. Int. Ass. Int. Hydr. Sci. Comm. Neiges Glaces. Colloque d’Obergurgl., 10-9-18-9, 1962, 212-219. THORNBURY, W. D., 1954. morphology. New York. WAHRHAPTIG, C., AND Cox, A., 1959. Rock glaciers in the Alaska Range. Bull. Geol. Soc. Amer., 70, 383-436. Principles of Geo- WILHELMY, H., 1958. Klimamorphologie der Massen- gesteine. Braunschweig. TABLE 1 Pollen and Spore Analysis of a Soil Sample from Toolong, N.S.W. Number Counted Pollen grains : Casuarinaceae : Casuarina .. a5 oe ns f Cyperaceae oe sa a brs 48 Eucryphiaceae : Eucryphia .. es bg sits 1 Fagaceae : Nothofagus subsect. Bipartitae 158 Nothofagus cf. cunninghamii re 15 Nothofagus Pe ud ihe 7 Gramineae sis ny, se wd 1 Hypericaceae : cf. Hypericum uf ae oe i ee EO Myrtaceae Ze att a a 17 cf. Pinaceae | ;. i a oe 4 Podocarpaceae : Dacrydium rh a oe 8 Microcachrys A: at ae 2 Phyllocladus a i. #5 4 Podocarpus .. ite ui sind 98 cf. Resedaceae a? Bh soe 10 Saxifragaceae : Quintinia .. a: ae A 93 cf. Umbelliferae BA o bie 13 Indet..3-< i$ gi ys Si 33 — 533 Spores : Monolete : Psilate a Ae: ae a 2 Verrucate a). a: si iy 4 Trilete : Psilate AR ne me we 14 Gemmate —~. aa “a bt 16 Verrucate-echinate ath ”) >”, Petrography of Coal Seam See Tables 3 and 4 for maceral and micro- lithotype analyses. Vitrinite The vitrinite content of the coal plies varies from 31% to 73%, averaging 42% for the full section and 52°% for the full section excluding shale bands. The vitrinite typically occurs as fine layers and small lenses associated with PETROGRAPHY OF A COAL SEAM FROM CLYDE RIVER GORGE, N.S.W. 111 TABLE 3 Maceral Analyses Ply No. Vitrinite Exinite Micrinite Semi- Fusinite Minerals Total fusinite 1 40 10 20 20 5 5 100 2 58 i 17 10 2 6 100 3 31 10 23 21 zi, 8 100 4 68 6 12 10 Trace 4 100 5 Shale Band 6 37 10 25 18 3 7 100 ri 64 5) 13 8 3 7 100 8 45 + 17 10 Trace 24 100 9 Shale Band 10 45 10 16 9 Trace 20 100 11 Shale Band 12 73 5 8 7 1 6 100 Composite including shale plies Sse 42 7 19 11 1 20 100 Composite exclud- ing shale plies .. 52 6 19 12 2 9 100 Calculated com- posite excluding shale plies = 52 a 17 12 3 9 100 TABLE 4 Microlithotype Analyses Ply, No: Vitrite Clarite Duro- Claro- Durite Fusite Carbar- Clay Total clarite durite gilite 1 8 2 47 29 1 12 1 — 100 2 22 6 49 12 1 6 3 1 100 3 Ta 3 22 25 14 23 if ] 100 4 36 12 42 5 1 2 1 1 100 5 Silty carbonaceous shale with about 10-20% quartz in the fine sand and silt size ranges. 6 5 1 55 31 2 5 i ci 100 7 21 7 62 3 ire 4 3 iste 100 8 1 I 61 + 1 6 25 ] 100 9 Clay with 10-20% quartz as in ply 5. Coal mainly as duroclarite, clarodurite and fusite. 10 7 I) 64 , 8 1 4 12 3 100 11 Similar to ply 9 but coal slightly more abundant. 12 36 8 39 2 tit ~ 11 Bae 100 Composite including shale plies .. 1B 3 38 12 3 7 7 13 100 Composite excluding shale plies .. 20 4 43 9 3 11 8 2 100 Calculated composite excluding shale plies .. 17 5 47 13 3 8 6 i 100 * Trace. afd other macerals (Fig. 3) and in places filling cells in fusinite or semifusinite (Fig. 4). The micro- lithotype analyses show that the major portion of the vitrinite occurs as clarodurite or duro- clarite. Sore of the vitrinite has a layered or striated appearance, with a lower reflectance than the more massive vitrinite. The two vitrinites, ‘higher and lower reflecting, are con- sidered to be analogous to vitrinites A and B described by Brown, Cook and Taylor (1964). Some of the vitrinite contains disseminated fine micrinite (Fig. 2). Exinite The exinite content varies from 49% to 10%, averaging 7°% and 6°% for the composite sections including and excluding shale bands respectively. It is present mainly as microspores and leaf cuticles (Fig. 2), with minor resin bodies, rare megaspores and some sporangia. Inertinite Micrinite is present generally as small irregularly shaped grains aligned parallel to A.C. COOK, AND EE W. READ the bedding, with some larger fusinized resin bodies (Fig. 5) up to 200 microns diameter in places exhibiting a lower reflectance rim. Most of the micrinite present falls into a reflectance range of 1:3% to 3-0%, relatively little occur- ring with a reflectance close to that of the vitrinite. The maximum reflectance recorded for micrinite was 5:5°%. Fusinite and semifusinite occur mainly as bands and lenses about 100 microns thick in places with cell cavities filled with material of the reflectance of vitrinite (Fig. 4). Cell structures are usually well preserved in the higher reflectance material. Only a _ few examples of bogen structure were noted in fusinite. The maximum reflectance recorded for fusinite was 3-5%. Minerals Mineral matter is represented by clay and quartz with occasional traces of carbonate, apatite and pyrite. The clay is very fine grained and generally disseminated within or between the macerals. Detrital quartz grains Fic. 2 Vitrinite, grey, with exinite, dark grey, occurring as leaf cuticles and microspores. light, oil immersion. Reflected 10x? PETROGRAPHY OF A COAL SEAM FROM CLYDE RIVER GORGE, N.S.W. 113 Fic. 3 Thin layers of vitrinite, grey, with micrinite, light grey to white and exinite dark grey. Reflected ght, oil immersion. are abundant at some horizons and range up to 100 microns diameter. The shale bands consist of fine grained clay with 10°% to 30°% of detrital | quartz grains typically about 100 microns in diameter. Comparison of the Clyde River Coal Measures Coal Seam with Coals from Greta Coal Measures There is a striking resemblance between the Clyde River coal and coal from the Greta Coal Measures (Table 5). The resemblance is present 700 x . at all scales from gross hand specimen features down to the fine structure of the vitrinites. Whilst the Greta Coal Measures coals show a range of petrographic composition they all have certain characters in common. These they share with the Clyde River Coal Measures coal described above. Major similarities noted are : (i) Overall maceral composition. Al- though the Clyde River Coal has a lower vitrinite and higher inertinite content than the typical Greta Seam TABLE 5 Maceral Analyses of Some Greta Coal Measure Coals Location and Seam Vitrinite Exinite Micrinite Semi- Fusinite Minerals Total fusinite Muswellbrook Brougham, Upper He Be 60 7 1] 15 2 5 100 Brougham, Lower os ar 55 10 10 15 2 8 100 Pinetrees Ss om ne 5l 9 12 19 3 6 100 Clyde River ae ne ay 52 7 17 12 3 9 100 114 (ii) (iii) (iv) (v) (vi) A. C. COOK AND H. W. READ anne » . . Fic. 4 Semifusinite showing scalariform pitting. reflectance. coal (Taylor, 1963), its maceral com- position lies well within the range reported for other Greta Coal Measures seams (C.S.I.R.O., 1967) (Table 5). The small size of the phyterals gives a very finely layered structure with small fragments of semifusinite, micrinite and exinite intimately mixed (Figs. 3, 5). The relative abundance of exinite. The abundance of fusinized resin bodies, often of very high reflectance (Fig. 5). The reflectance profile of the vitrinite, also the general similarity of the vitrinite which often has a finely striated appearance, probably due to the presence of exinite-like material (Taylor, 1965). The presence of significant amounts of durite, an unusual feature in N.S.W. Permian coals. (Note: Durite quoted in analyses of the Bulli Seam (Taylor, 1963) would now in the main be referred to as microite and fusite.) Cell lumens filled with material of vitrinite Reflected light, oil immersion. 1005<2 (vii) Dominance of trimaceral over birnaceral and monomaceral micro- lithotypes (Table 4). The Significance of the Similarity between the Clyde River and Greta Coal Measures Coals The Clyde River Coal Measures have been considered to be a time equivalent if not a southern continuation of the Greta Coal Measures (Harper,1915). Brown, Campbell and Crook (1968) suggest that the Clyde River Coal Measures might be “‘ somewhat older ”’ than the Greta Coal Measures. This view is supported by Helby (1968) who assigned an Upper Allan- dale age on the basis of the spore assemblage. The similarity in the petrography of the coals suggests that the depositional facies were similar in many respects. It is difficult to equate the general sedimentary environment of a small closed basin situated in an isolated depression in the basernent with that over the extensive areas in which the Greta Coal Measures were BREePTROGRAPHY OF A COAL SEAM FROM CLYDE RIVER GORGE, N.S.W. 115 Fie. 5 Durite containing a large fusinized resin body. Reflected light, oil immersion. deposited. However, the only dissimilarities between the coals attributable to this difference in scale are the relative abundance of detrital quartz grains in some coal plies and perhaps the greater inertinite content of the Clyde River coal although some Muswellbrook Greta seams have a similar inertinite content. This apparent lack of dependence of the coal type on the size of the coal forming basin is more in accord with an autochthonous origin than the allochthonous origin for the coal sears which Booker on balance appeared to favour (Booker, 1957, p. 40). In both the Greta and Clyde River Coal Measures coals large plant fragments are very rare. This may be due to greater comminution of plant material than was common later in Permian times but is more probably due to an absence of large tree-like vegetation and an abundance of smaller forms. The presence of abundant detrital quartz of sand size in certain layers in the Clyde River Coal Measures coal, the absence of brecciated T00 x. coal, together with the regularity of bedding, makes it difficult to accept the inttinesgre floating raft theory of peat formation put forward by Duff (1967). Currents strong enough to bring in even relatively fine detrital sediment could probably cause disruption of floating rafts of peat, unless they were very firmly anchored. This could produce disturbed bed- ding analogous to that found at the margins of washouts in British coals (Raistrick and Marshall, 1948, pp. 84-85). As disturbed bed- ding has not been reported for the Greta coals, nor the Clyde River coals, it seems more probable that the peat constituted a coherent layer which was occasionally inundated by sediment-carrying water. Further, the small size of the phyterals could be indicative of the small types of plants often found in a marsh environment. An explanation must be sought both for the similarity of these two groups of coals and the differences they exhibit compared with the Newcastle and Illawarra Coal Measures. The presence of marine rocks above the Clyde River 116 and Greta Coal Measures could be held to account for such features as the locally high sulphur contents but seems unlikely to have influenced the gross petrography of the coals. Climate, by controlling both the type of flora and the peat-forming conditions, can influence the petro- graphic features. It is therefore suggested that the similarity of the Clyde River and Greta Coal Measures coals is due to a similar climate. Rank Vitrinite reflectance measurements were made on six of the coal plies and on the composite sample excluding shale plies (Fig. 6). The maximum reflectance was measured in each case because this is independent of grain orientation. Following Brown, Cook and Taylor (1964), an attempt was made to distinguish vitrinites A and B. It proved to be more difficult to distinguish vitrinites A and B by their appearance for the Clyde River Coal Measures coal than is normally the case for coals of comparable rank. Subjective estimates of a suitable reflectance value for use as a cut off between the vitrinites were made for four samples during the measurement of the reflec- tance. Figures of 0-79°9% (composite), 0:79%% (ply 2), 0-82%% (ply 3), and 0:83°% (ply 12) were obtained. Subsequent inspection of the fre- quency diagrams suggested that 0-80°% provided the most natural separation of the higher and lower parts of the reflectance range and this figure was used. Smyth (1968) suggested that by selecting only the vitrinite occurring as vitrite a less subjective method would result for determining the reflectance of vitrinite A. This procedure did not provide a reliable criterion for the sub- division of vitrinite in the case of the Clyde River Coal Measures coal, since considerable amounts of high reflectance vitrinite occur in bimaceral and trimaceral microlithotypes and conversely low reflectance vitrinite occurs in vitrite. Comparison of Table 4 with Fig. 6 shows, for example, that plies 3 and 6 have very low vitrite contents (119% and 5°% respectively) but a relatively high mean maximum reflectance for the vitrinite (0-83°% in both cases). The range of reflectance found in the six plies and the composite sample is 0-79°% to 0-85°% for the mean maximum reflectance of all the vitrinite suitable for reflectance measure- ment and 0-82°% to 0:86°%% for the vitrinite A as defined above. The mean maximum reflec- tance of the vitrinite A in the composite sample, 0-84°%, is considered to be the figure most suitable for use as an indication of rank. AC, COOK AND Tee READ Comparison of the Rank of the Clyde River Coal Measures Coal with That of Some Other N.S.W. Coals The Clyde River Coal Measures coal (R max. vitrinite A 0-84°%%) is of much lower rank than the stratigraphically higher coals of the Illawarra Coal Measures in, for example, the Wollongong area sorne 80 miles to the N.N.E. where the Bulli Seam vitrinite A has a mean maximum reflectance in the range 1-277 =" 457. The rank of coal is generally considered to be a function of the temperature attained during burial metamorphism (Francis, 1960). Increased cover results in increased temperatures and therefore rank. For any given cover rank will be a function of the geothermal gradient. Igneous activity can, by locally increasing the supply of heat, cause a rise in rank (see e.g. Kisch, 1966). At the sample location the Clyde River Coal Measures have a cover of about 1,800 feet to the top of the Nowra Sandstone. The strati- graphically higher Berry Formation, Illawarra Coal Measures and the Triassic rock units are unlikely to have been in excess of 1,000 feet in total thickness since all of these units thin to the south in the region of Nowra (see locality map, Fig. 1). Therefore, the maximum cover on the Clyde River Coal Measures is unlikely to have been greater than 2,800 feet. The total cover on the Bulli Seam in the Wollongong area to the top of the Wianamatta Group is also unlikely to have exceeded 3,500 feet, a figure of 2,500 feet being more probable. In the Planet Oil East Maitland bore, Greta Coal Measures coal from 4,635 feet has a vitrinite reflectance of 17449, (C.SdR2Os 1964) sy the coals of the Tomago Coal Measures which out- crop near the East Maitland bore have a vitrinite A mean maxirnum reflectance of 0-83°% (Taylor, 1968), so that in this case it is possible to associate a change of reflectance from 0-83%% to 1:44°% with an increment of cover of about 4,000 feet. The difference between the rank of the Clyde River Coal Measures coal and the Bulli Seam in the Wollongong area is almost the same. If the Hunter Valley data is used for the Southern Coalfield an additional 4,000 feet of cover for the Bulli Seam would appear to be necessary to explain this difference on the basis of depth of cover. This in turn would necessitate a long and important episode of post-Wianamatta sedimentation ; an episode of which there is now no trace. There remains the possibility that the geo- thermal gradient was much greater in the PETROGRAPHY OF A COAL SEAM FROM CLYDE RIVER GORGE, N.S.W. 117 Ply | Ply 6 max. all Vitrinite °79 Di max. all Vitrinite 83 Di Di 40 Measurements max. Vitrinite A 82 40 Measurements mox. Vitrinte A ° 85 FREQUENCY % FREQUENCY % a.7 0-8 09 Ce a Ge Reflectance %& Reflectance % 7: a! Ply 2 max. all Vitrinite °80 max. Vitrinite A °83 max. all Vitrinite -8] Ply 7 max. Vitrinte A ~83 15 Al Dl 164 40 Measurements 40 Measurements ° ° o is > > ole {S) Z é wi =) =) o Qo Ww od rd wr ws La O-7 o8s o9 Ory’ 0-8 Oo:9 Reflectance % Reflectance ¥, max. all Vitrinite 83 Ply ped R max. all Vitrinite 84 Al Ply 3 40 Measurements | max. Vitrinite A °85 78 Measurements R max Vitrinite A °85 te) ) x o > rel 6) z 2 WW ra) 2) =) (e] g Ww uJ fig a “5 od On 0:8 0-9 OF 0-8 O29 Reflectance % Reflectance % Clean Coal Composite max. all Vitrinite 81 m1 Wl mox. Vitrinite A -84 84 Measurements 1S 32 VITRINITE REFLECTANCE PROFILES FOR Se SOME PLIES AND CLEAN COAL 2 COMPOSITE. a us Or os Reflectance % oS Fic. 6 Vitrinite reflectance profiles for some plies and clean coal composite. 118 Wollongong area, perhaps due to extrusive and intrusive igneous activity. Any such thermal effect would have to be regional rather than local since, apart from very localized contacts and areas of carbonized coal, the rank of coal in the Wollongong area varies gradually and does not appear to be affected by any of the known igneous bodies. The Wollongong area certainly is affected by post-Permian intrusions and there appears to have been a major area of Permian vulcanicity in the Port Kembla to Kiama area. The rank of the Bulli Seam, however, declines shghtly to the south (that is, towards Kiama) from Wollongong (Wilson and Cook, 1968). The Clyde River Coal Measures are not intruded by any igneous bodies but there are extensive areas of Tertiary basalts immediately north and north-west of the Clyde River gorge and there is the large mass of the Milton Monzonite which outcrops about eight miles to the south-east. It is therefore difficult to explain the difference between the rank of the Clyde River Coal Measures coal and that of the Bulli Seam in the Wollongong area, either on depth of burial or on the relative abundance of igneous activity. To this extent the difference can be held to be anomalous. Conclusions 1. The Clyde River Coal Measures coal is only moderately rich in vitrinite and _ contains significant amounts of exinite, mainly micro- spores. The phyterals are typically relatively small with trimaceral microlithotypes pre- dominating. 2. The petrography, chemical analyses and rank of the Greta and Clyde River Coal Measures coals are closely similar. 3. The similarity of petrographic composition and characteristics between the Greta and Clyde River Coal Measures coals probably reflects a similarity of the types of vegetation which gave rise to the coals. This in turn could reflect a similarity of climate. 4. Although there may have been local zones of allochthonous accumulation in the coal basin, the bulk of the Clyde River Coal Measures coal is essentially autochthonous in origin. 5. The mean maximum reflectance of the vitrinite A is 0-84°%, indicating that the rank of the coal lies in the lower part of the range of bituminous coals. 6. It is difficult to relate the rank of the Clyde River Coal Measures coal to that of the Bulli A.C, COOK AND AW. READ Seam in the Wollongong area on the basis of maximum depth of cover. Acknowledgements The authors gratefully acknowledge the donation by the Joint Coal Board of a grant to Wollongong University College for the purchase of a photometer, and Jena Glaswerk Schott and Gen. for the donation of the glass standards used with the photometer in the reflectance determinations. The proximate and chemical analyses were carried out by the laboratories of Australian Iron and Steel Pty. Ltd., Port Kemibla: References Booker, F. W., 1957. Studies in Permian sedimenta- tion in the Sydney Basin. N.S.W. Dept. Mines Tech. Reports, No. 5, 10-62. Brown, D. A., CAMPBELL, K. S. W., and Crook, K. A.W.,1968. The Geological Evolution of Australia and New Zealand. Pergamon Press. Brown, H. R., Cook, A. C., and Tayvtor, G. H., 1964. Variations in the Properties of Vitrinite in Iso- metamorphous Coal. Fuel, Lond., 43, 111-124. C.S.1.R.O., 1964. Report on the Deep Seams of Greta Age from the A.O.G. Loder Dome No. 1 and the Planet Oil (East Maitland) No.1 Bores. C.S.I.R.O. Division of Coal Research Misc. Report, 246. C.S.1.R.O., 1967. Characteristics of coals from the Liddell District, Northern Coalfield N.S.W. Coal esearch Laboratory, Division of Mineral Chemistry, Tech. Comm., 49. Durr, P. McL. D., 1967. Cyclic Sedimentation in the Permian Coal Measures of New South Wales. Journ. Geol. Soc. Aust., 14, 293-308. FRANCIS, W., 1960. Coal. Its Formation and Com- position. Edward Arnold, London. HARPER, L. F., 1915. Geology and Mineral Resources of the Southern Coalfield. Memoirs Geol. Survey of N2S:W.,.No 7; MELBY, Kk... 1968: Kiscu, H. J., 1966. Personal communication. Carbonization of semi-anthracitic vitrinite by an analcime basanite sill. Econ. Geol., 61, 1043-1063. McELrRoy, C. T., and Rose, G., 1962. Reconnaissance Geological Survey: Ulladulla 1 Mile Military Sheet and Southern Part of Tianjara 1 Mile Military Sheet. Geol. Survey of N.S.W. Bulletin, No. 17. RaISTRICK, A., and MARSHALL, C. E., 1948. The Nature and Origin of Coal and Coal Seams. E.U.P., London. SmyTH, M., 1968. The Petrography of some New South Wales Coals from the Tomago Coal Measures. Proc. Aust. Inst. Min. Met., No. 225, 1-9. Taytor, G. H., 1963. Petrographic Data on some New South Wales Coals. C.S.J.R.O. Division of Coal Research, Investigation Report, 49. TayLor, G. H., 1965. The Electron Microscopy of Vitrinites, in Advances in Chemistry Series, No. 55, ““ Coal Science ’’, 274-281. TayLor, G. H., 1968. Personal communication. TayLor, G. H., and ZEIDLER, W., 1962. Embedding Coals and Cokes in Plastic for Microscope Examina- tion. Jour. Roy. Microscopical Soc., 80, 287-290. WItson, R. G., and Cook, A. C., 1968. Unpublished. work. (Received 21 May 1968) AUSTRALASIAN MEDICAL PUBLISHING CO. LTD, SEAMER & ARUNDEL STS., GLEBE, SYDNEY, 2037 iS ae ie ~ ” < 1 Fy is oh Ryans a i~ Ni A P?. Sa ee = SAS aah coy go, Ci Go eA > Seah. — x is Sen be sr 2 eae % > ts ON ae nae ae ~ if; a Meee - é 2 oo L =e t hae ee ge ee: $F tet =e Oy “an: co =) ( , Bae PEC RACES sa gsr a Patrons ee Cer ee Ole 1s caeicy- THE. ‘GoveRNOR-GENERAL OF. THE CommMonWEALTH ‘OF AUSTRALIA, oat Ruger, HONOURABLE LORD CASEY, P.C., G, c. M.G., C H., D.S.0., M. c, K.St. Je His EXcELLENCY. THE Governor. OF New Sourn Wares, : SIR RODEN CUTLER, VG, K.C. M.G., “C.B.E. x ee a Le President eo} y eae on eae oay 2 ) fs 5 Seri aes ANGUS +H. Low, Bite ee As ag ae as = “ 2 | Vice-Presidents Seas AB oes : Fie Ot OWS BG) POGGENDORFF, B.Sc.Agr, Se, F.R.S:, LS oan ae A. H. YOIREY, | D.Sc, # eke “Honorary Secgetavics | oe 3 A. REICHEL, ‘Ph. D., M86. S Honorary Treasurer os is : = ee oi ‘CONAGHAN, bea) SEN bey ei Oe | es Ye fe Members of Council hea eA BURG. wcrc. iS so DB. LINDSAY, B.5c., uta, D.Phil, CAMERON, ‘M.A., B.Sc. (sala), D.I. ya ee aaa Sr fe eS NEUHAUS, msc. __ J. GRIFFIN, B.sc. — tage _ J. P. POLLARD, pip.app.chem. E. KITAMURA, B.a., B.Sc, Agr. ta. 1 RB Thermal neutrons .. ae 2-5 Fast neutrons a ws 10 Protons ee ae at 10 Naturally occuring «-radia- tion. i ee a 10 Heavy recoil nucleii .. Bs 20 TABLE 1 Maximum Permissible Doses Extract from the Regulations under the Radioactive Substances Act, 1957, No. 5 and Including Amendments, 1962, No. 245 and 1963, No. 112 (Government of N.S.W., 1957) Categories Organs and Lenses of the Eyes (for “‘ whole body ”’ exposure) Gonads, Blood Forming Maximum Permissible Doses Skin and Thyroid Gland Skin, Deeper Tissues of (for ‘‘ whole body ”’ Hands, Forearms, Head, exposure) Neck, Feet and Ankles Radiation Worker over 18} 5 rem per year or 3 rem| 8 rer per 13 weeks from| 20 rem per 13 weeks, but years of age. per 13 weeks from external and/or internal sources. external sources only. not more than 3 rem to the lenses of the eye over the same period. Radiation Worker over 16,| 1-5 rem per year, external] 3 rem per year, external but under 18 years of age.| or internal radiation. Occupationally Exposed| 1-5 rern per year, external Workers. or internal radiation. General Population. 0-5 rer per year. to an absorption of 5-24 x 101% eV, or about 83 ergs (1 eV = 1-6 X 10-” ergs) per gram of air. Rad: The unit of absorbed dose and equal to an absorption of 100 ergs/gram, of absorbing substance. This latter need not be air. Roentgen—equivalent-man (rem.) : Biological measure of absorbed dose. The absorbed dose of any ionizing radiation which has the same biological effectiveness as one rad of X-radiation with average specific ionization of 100 ion pairs per micron of water, in terms of its air equivalent, in the same region (this is approximately equivalent to the effect of 200 k.v.p. X-rays) Gos fe fe 18S15)9))e Dose (rem) ose (rad) x "KBE. where R.B.E. = Relative Biological Effectiveness. == thei inverse ;ratios of “the energy absorptions of different radiations which produce equa] biological effects. or internal radiation. 3 rem per year, external or internal radiation. Considerations in Assessing Radiation Dosages with Film Badges Since there is a considerable difference between. the nature of a film emulsion and human tissue there is also a corresponding difference between the response of film and of tissue to ionizing radiation. This difference is not only one magnitude but also of energy dependence. Further, there is a lack of linearity in the relation between the exposure to a particular type of radiation and the corresponding photo-. graphic density. For this reason the dose is usually measured in rads and then, at least in principal, it can be translated to an absorbed dose by means of conversion factors which allow one to arrive at the R.B.E. dose (as defined), rems. Another consideration is that some organs. are more sensitive than others to radiation and for this reason the Maximum Permitted Dose: is weighted in favour of whether the exposure: is “whole body ” or only to extremities, such. THE FILM BADGE SERVICE IN NEW SOUTH WALES as hands or feet. These considerations and the nature of the particular source of radiation serve also to determine the location of the film badge on the wearer’s body. In some cases, more than one badge may be worn at the same time. UNFILTERED 300mg jem2 PLASTICS 0-040" DURAL 0-028" Sn + 0-012" Pb FILM RESPONSE RELATIVE TO COBALT 60 10 100 1000 PHOTON ENERGY~keV hie, 2 Response of photographic film to various photon en- ergies, all for the sarne dosage (Heard and Jones, 1965) 10000 Figure 2 shows the response of a photographic emulsion to various photon energies. It also illustrates the effect of the various filter sections used in film badges. THE BADGE Generally the field to be monitored contains different types of ionizing radiations at a variety of energies. Since, from Fig. 2, these divers energies cause different effects on the film for the same dosage, one can only hope to calculate a correction factor to relate the exposure to the density of the film. For this reason, a number of filter sections have been incorporated in the badge and Fig. 2, also shows the response of the films behind the various filter sections used, while Fig. 3 and 4 show the R.P.S. (Radiological Protection Service, Sutton, U.K.) and the A.E.R.E./R.P.S. (Atomic Energy Research Establishment, Harwell) badges respectively. A set of filters commonly used for normal photon monitoring are (1) plastic with a density of 300 mg./cm.?, (2) plastic plus a 0-040” duralumin filter, (4) plastic plus 0-028” tin plus 0-012” lead, (5) an open window. In the earlier R.P.S. holders the filter section were adjacent to one another (Fig. 3) and it was found that there was an error introduced in that radiation passing through the tin filter was being scattered into the dural region and vice versa ; and, further, there were insufficient filter sections to allow an adequate dosage formula to be 121 developed. The later A.E.R.E./R.P.S. holder overcame this by placing a cadmium filter between the dural and the tin and also improved the performance of the badge by using two different thicknesses of plastic filter sections. The cadmium would, of course, still cause side scatter but due to its lower atomic number not to as great an extent. Apart from the one use mentioned above the cadmium also fills the function of a slow neutron monitor. For the A.E.R.E./R.P.S. holder a formula has been developed to cover (X + y) photon radia- tion and using a special Kodak Radiation Monitoring Films. With D to represent the apparent dose behind each filter section, we have: Photon dose D to Badge= D D.4, — D [Dun + cha zl 300 7" = which is effective over the energy range 15 keV to 2 MeV (Heard and Jones, 1965). This latter badge is coming into general use in place of a variety of badges previously used. In New South Wales, the R.P.S. holder is at present being used concurrently with the A.E.R.E./R.P.S. one, but as more of the latter become available, it will replace the former. PLAN SECTION FQ) NIN B-hylon filter ~aiaseae open window Ae- ourg/s nylon ude filter As Ai-ting nylon Bs filter pp Eefilm one efter nylon hinge tine nylon filter The film holder designed by the R.P.S. consists of a plastic case with two pairs of metal filters Fic. 3 The R.P.S. Film Badge (Heard and Jones, 1965) | 122 Although neutrons can be monitored with the new badge, there has never been a real problem outside of atomic energy research establishments, since very little industrial use is made of them. At present there are only two or three commercial neutron sources in New South Wales ; these being used in portable soil moisture meters. THE FILM Since the degree of darkening is dependent on dose, though not in a linear manner, it is clear that the larger a range of optical densities the film can cover the larger will be the range of dosages it can record with any degree of accuracy. For this reason, Personnel Monotoring Films frequently are either of the type that have two emulsions on the one acetate base or they consist of two separate single-emulsion sheets in the one pack. FILTER TYPES Window 50 mg/cm’ plastics 300 mg/cm’ plastics 0:040” Dural 0028” Cd+0:012” Pb 0028” Sn+0:012” Pb 0-012” Pb edge shielding 0°4 g of indium PNA YN > Fic. 4 The A.E.R.E./R.P.S. (Heard and Jones, 1965) In each case, one emulsion is generally of high sensitivity so that, for example, a dosage of 1 rem of y-radiation will cause a net density of 3, while the other is a low sensitivity emulsion in which 100 rem will cause a net density of about 2. Various combinations of measurements are used. In the twin emulsion case, most measure- ments are made through both emulsions together and only for apparently high dosages is the high sensitivity emulsion stripped off and measurements are made through the remaining one. This is the more convenient method since only one film instead of two has to be developed and, in any case, most dosages are relatively low, this making it rarely necessary to use the slow emulsion. The films are 3cm. X 4cm.: which is the same as dental X-ray films. As a matter of fact, for many years, dental films were used in Film Badges. The emulsions vary in thickness from 2 to 5 X 10-2cms “depending con athe ‘manufacture. A. W. FLEISCHMANN Mechanics of the Film Badge Service The Film Badge Service can be divided into two distinct categories as far as its actual operation is concerned. On the one hand, there is the purely clerical side which is concerned with the sending and receipt of films and also with the recording of results, while on the other hand, the Physical side of the service is concerned with calibrating and developing films, measuring density corresponding to the various filter sections and calculating the radiation dosages. Fic. 5 Developing the films As far as the sending and receipt of films is concerned, this has been automated as far as possible by use of items such as addressograph machines to print organizations names and addresses on to envelopes and assessment sheets ; assessment sheets backed with copying ink to simplify carbon copying; visible index card systems with plastic signs to indicate who should receive films next, when the last films were returned, and other necessary information. The developing of films is carried out under rigidly controlled conditions of temperature, solution quality, and agitation, and about 300 films are developed twice a week. After this, THE FILM BADGE SERVICE IN NEW SOUTH WALES each film has an identification code stamped on it to record the week in which the film was developed, the year and a wearer’s identification number. Next, the density of the various filter sections is measured and recorded on a measuring sheet prior to the calculation of actual dosages. Every batch of new films is calibrated for a variety of dosages against a Co-60 standard source (Fig. 7) and also for a variety of X-ray energies. After a calibration for the particular Fic. 6 Measuring the density of films batch of film has been carried out, it is sufficient to calibrate with Co-60, and the X-ray exposures are purely made for purposes of checking previous results. New, unused films, are sealed in plastic tubing together with silica gel, and are stored in a refrigerator until required. Results to Date While the dosage of radiation received by a person in the course of his duties may fluctuate somewhat, the general approach is to look for one or more of three possibilities in the light of limits set by the maximum Permitted Dose Rates as specified by the Radioactive Substances Regulations. These considerations are (1) the whole body dose rate approaching, or in excess of 3 rem in 13 weeks or 5 rem per year, which classifies it as an Excessive Dosage (Regulation 3) ; (2) the whole body dosage known or suspected to exceed one rem in one week, or 3 rems in one month which again is an Excessive Dosage (Regulation 6 (2) (b)); (8) the dosage simply higher than the average expected dose. Although a number of radiologists, medical radiographers and veterinary surgeons have on occasions recorded Excessive Doses the majority, by far, have occurred in the field of industrial radiography. For this reason, Cumu- 123 lative Dosage cards are kept for all Industrial Radiographers and for a few people in the other categories shown in Fig. 1. Over a period of 6 years the cumulative dosages for industrial radiographers have been as follows : TABLE 2 Cumulative Dosages for Industrial Radiographers Dose Range} 0-1 | 1-2 | 2-3 | 3-4 | 4-5 |Over| Total (rem) 5 Number of persons 27 9 5 5 2 ly 49 1962, |_| ——, —— , —__ ,—__ —_.. —_|—_ Percentage of total 55 | 18 | 10 | 10 4. 2 — Number of persons 34 6 6 3 1 5 55 1963, | | —— —_ | ,—_—_ —_ —— ———— Percentage of total 62 | ll | 11 5 2 9 — Number of persons 51 6 5 2 3 1 68 1964 .———_. ———. —__ ____ ____. —__ ___ Percentage of total 75 9 7 3 5 1 —_ Number of persons 61 7 2 3 1 4 78 1965 |__|, —_|—__|—___ |__| Percentage of total 78 9 3 4 1 5 — Number of persons 61 | 10 6 2 1 6 86 1966 >-———— | —_— Percentage of total 7 ie 7 2 1 7 == Number of persons 73 9 1 4 1 1 89 1967 ——— | — | —_ |_| Percentage ot total 82 | 10 1 5 1 It is noteworthy that although the number of industrial radiographers has increased by 90°%% over the period, the percentage dose distribution has remained substantially constant as a result of increased precautions and improve- ment of equipment. Industrial radiographers are particularly likely to receive high dosages of radiation because (1) the nature of the work may make adequate shielding difficult, (2) it is not always possible for the operator to move far away from the exposed source, (3) they use comparatively large radioactive sources or high voltage X-ray machines, and (4) they are generally totally unskilled operators who have been given only the most rudimentary instructions. The final 124 point is probably the most important one, and it is hoped to improve this matter in the near future by the introduction of an Industrial- Radiography course. Nearly all other people working with sources of ionizing radiation have had at least some training which will acquaint them with the properties and safe handling of ‘sources of Jonizing Radiation. It is significant that of 12 “‘ Radiation Incidents ” in New South Wales over the period April, 1956 to October 1964, ten involved industrial radiographers (Fleischmann, 1965). EIGe 7 Calibration of films with Co-€0. Accuracy of Film Badges A number of experiments have been carried out by a variety of personnel to determine the accuracy of the Film Badge method of dose assessment. The problem has been approached in two ways. On the one hand, a central organization has subjected a number of badges to a variety of dosages at various energies and has then required some commercial or governmental bodies to assess the dosages. On the other hand, a number of controlled experiments have been carried out where each facet of the film badge service has been examined, and on estimate of accuracy and reliability arrived at. A. W. FLEISCHMANN In February, 1965, Gorson, et al., at Jefferson Medical College (U.S.A.) ordered thirty film badges from each of 12 suppliers and at the same time the Radiation Safety Officer at the University of Pennsylvania ordered 28 badges from each of 11 suppliers (the same suppliers being involved in each case). The companies were informed that the badges would be exposed to X- and y-ray exposures only, and to mixtures thereof. The badges were exposed to y-rays from Co-60 and Ra-226 and X-rays in the H.V.L. (Half Valve Layer) range 1-4 mm. Al to 3-3mm. Cu. A noamber of duplicate exposures were also made. To quote the authors (Gorson é al., 1965) : “ Results showed a considerable range in both accuracy and consistency among the 12 companies tested. The percentage of the reported values in error by more than -+50%, ranged from 7 to 50. The percentage of duplicate exposure readings differing by a factor of 1-5 or more ranged from 0 to 75. Most companies were considerably more successful in evaluating exposures to Co-60 and Ra-226 than they were in reporting the exposures to X-rays on to mixed X- and y-radiations ”’. The paper does not describe the actual form of any of the badges and the types of films used by the various suppliers, but the A.E.R.E./ R.P.S. badges with British Kodak RM film would certainly not have been included since neither existed at that time. In another paper, also in 1965, the School of Medicine at the University of Miami (Menker and Dauer, 1965) acquired film badges from 16 companies in the U.S.A., exposed them to X- or y-radiation, but not to mixed radiation, and then asked the companies to make a close assessment. They also informed the companies of the type of radiation that each film received. The films were also stored under carefully controlled conditions of temperature and humidity. The percentage deviation from the correct dose found in this survey was, for each type of radiation, in the range (quote) : “ Radium 226 —T2% to+ 50% Cobalt 60 —86% to + 52% 250 K.V.P. X-rays —62°% to + 119% 80 K.V.P. X-rays —63°% to +2635%% ”’ No two companies had used the same type of film holder in this test. Thirteen companies used various types of plastic holders and three companies used metal badges. It is clear from this survey that the companies do not go anywhere near the +20°%% that most THE FILM BADGE SERVICE IN NEW SOUTH WALES of them advertise and actually have trouble staying in the range +509. It is remarkable that the y-radiation assessment should be so inaccurate when one considers that most films are calibrated with y-radiation, and hence there is no need to use the filters to determine an X-ray correction factor. It is also regrettable that the greatest range of error is in the 80 K.V.P. (Kilo Volts Peak) range which is that used for most medical diagnostic radiography. The next series of experiments was carried out by H. Brodsky and others for y-radiation dosage assessment only, over a period of time in 1963 and was reported in Health Physics (Brodsky et al., 1963, 1965; Kathren, 1963). These workers made an experimental study of the various sources of error that are likely to influence the assessment. These include such factors as (1) temperature, (2) humidity, (3) how often the films are replaced, (4) how long they are stored, etc. They also found that most of the serious errors were also applicable to other systems in some respects. Under ideal con- ditions, they found that the assessment should be accurate to +20%. More recently in 1965, a survey was carried out in Britain to compare the A.E.R.E./R.P.S. badge with an earlier metal badge used by the Radiological Protection Service. This experi- ment was performed by Langmead and Adams (Langmead e¢ al., 1967) and essentially they compared tests carried out on the new badge plus film with tests carried out on the older badge in 1961. Both sets of experiments were carried out on @-, y- ; X- and mixed radiations. The results of the two experiments were summed up in a table, which is reproduced ere : TABLE 3 Summary of Accuracy attained in the two Experiments 1961 Experiment | 1965 Experiment Range of pressed tin-plate AVE KE /K: PS: Accuracy badge (percentage | badge (percentage (+%) of 94 assessrnents) | of 84 assessments) 0-20 63 70 21-40 16 19 40 21 ll It is clear that the newer badge offers a greater degree of accuracy ard that, in par- ticular, the number of assessments, out by more than 40%, has been greatly reduced. These results are further pleasing in that, in this experiment, both mixed radiation and y-radia- tion were included. 125 In New South Wales, the Film Badge Service has been checked in two ways. One is by asking a number of operators to wear pocket dosimeters alongside their film badges, and the other is by exposing films to a variety of dosages and types of radiation and at the same time measuring the dosages on a calibrated standard dosimeter. The former method is, of necessity, inaccurate in that one relies on an instrument (the dose- meter) whose qualities and accuracy maybe unknown, and also on unskilled persons who are asked to daily record the readings on the Pocket Dosimeter. Further, the devices have to be recharged from day to day and this, coupled with sources of error in reading a difficult scale, makes the method only a rough check. The second method, that of comparing films with standard dosemeters, has been carried out on a number of occasions. Experiments carried out in the Division of Occupational Health using High Energy X-rays and a source of Ir!? on both tne Kap. S, and the Aan a Eo PS, holder have shown that for a single type of radiation pure X-ray or purely y- the badges are accurate to the extent that they read 159% to 20% low but for a mixture of X- and y-rays they read up to 40% to high. The interpretation of X-ray dosage in this latter case is accurate to within 10°% (low, as before) but the y dosage is over 100°%% too high. The cause for this is that the harder X-rays are of sufficient energy to penetrate the tin filter and cause an over estimate exaggeration of the apparent y- dosage. The formula proposed by Heard and Jones (1965) overcomes this error and produces a gross assessment as against a separate X-ray and y-ray dosage but to date we have not had the opportunity to check this because we have not been able to obtain the same films as the ones they used. Other Methods of Dosimetry Another type of dosimeter often used in conjunction with film badges is known as the “ Pencil’? or ‘‘ Pocket’”’ Dosimeter. As _ its name implies, it is shaped more like a propelling pencil, and is worn clipped on to the operator’s pocket lapel. It operates on the “ gold-leaf electroscope ” principal in that charging the dosimeter induces a charge on to a fibre, which causes it to move away from a second electrode inside the chamber. Ionizing radiation causes the change to leak away and the fibre tends to return to its rest position. As it returns, it moves axial to a ¢ 126 graduated scale in the focal plane of a lens system, and the dosage can then be read off by looking through the instrument. As mentioned, Pocket Dosimeters are sensitive to heat and humidity and also to mechanical damages. They also have the disadvantage that they (a) are relatively expensive, (0) require a charging unit, which is also expensive, (c) do not provide a permanent record of their readings (whereas Film Badges are always available for reassessment) and (d) they are made of relatively heavy metal, which in itself will act as a filter to the radiation, and will effect the “ energy dependence’”’ of the response, particularly in the lower energy ranges. A more recent addition to the field of Personal Dosimetry is the Thermoluminescent Dosimeter. This relies on the principle that some crystalline substances store the energy of absorbed ionizing radiation and release it as light when heated. The dosimeter, then, consists of (1) the powder, which is commonly lithium fluoride (Lif), (2) a device to weigh out the powder, (3) the dosimeter which contains the powder either in a glass or plastic phial or on a metal surface, and (4) the dose reader and print-out mechanism. Thermoluminescent dosimetry systems have the great advantage that their dose responses are substantially energy independent, and that they suffer little fading with time. The main disadvantage is that of initial cost and that a direct substitute for the film badge has not been developed. By this latter point, it is meant that generally the Thermoluminescent Dosi- meter is used as a dose reader in radiation therapy procedures. Most personnel dosimeters developed to date are similar in form to the Pocket Dosimeter, where the inner element has been replaced by a glass phial containing the thermoluminscent powder. The combination of metal case and glass phial would seriously impair the ability of the device to measure X-ray dosages. One organization has developed a flat metal plate which contains the powder in a recessed section but this is still in the developmental stage. In spite of the above problems, which may have been solved by now, the main obstacle is, as mentioned before, that the cost of setting up and maintaining such a system is very far in excess of the same two factors for a film- badge service. Other methods of dosimetry will not be mentioned here since they are mainly designed for measuring large or massive dosages and rarely are capable of going below 1 rem. A. W. FLEISCHMANN Concluding Notes The radiological Advisory Council (N.S.W.) has recently decided to adopt a recommendation made by the I.C.R.P., that “ workers who have been identified as being in conditions of work such as that their exposure is most unlikely to result in doses exceeding 309% of the annual maximum permissible doses, individual moni- toring and special health supervision are not required. For these persons, monitoring of the working environment will usually be sufficient, even though in some cases individual monitoring may be desirable, for example, to obtain statistical information on the exposures”’ (Recommendations I.C.R.P., 1965). The conditions under which this recom- mendation is to be applied in New South Wales, will be that (1) the organization must consis- tently record less than 30% of the maximum permitted dose, (2) the organization must have been using film badges for at least two years, and (3) annual inspections of the premises must be carried out. This change will considerably reduce the number of persons wearing film badges in New South Wales. At present, for example, about 900 dentists are wearing film badges and all three of the above conditions apply to most of them. Other categories of workers will be affected to a lesser extent. Consideration is also being given to the use of computers. This has particular reference to the new A.E.R.E./R.P.S., holder, where, as previously shown, a fairly straight forward formula exists to evaluate dosages. This formula is further aided by short cut steps that allow one to avoid making numerous calculations if the measured densities are below predeter- mined values. The use of computors would be aided by having the output from the densitometer connected directly to a tape printer via a digital voltmeter, then the densities could feed straight to a computor once the measurements are completed and the final print out can be so arranged that it can be sent directly to the person concerned. It is not a difficult task to organize the programme to give any required statistical information, such as how many persons in each category received film badges, how many high or excessive dosages have been received, etc. These changes are still in the planning stage and could considerably simplify the system if implemented. THE FILM BADGE SERVICE IN NEW SOUTH WALES The author wishes to thank the Director- General of Public Health for permission to publish this article, and Mr. R. deVries, of the Division of Occupational Health, who took the photographs. Summary It was endeavoured to give a general survey of the Film Badge Service in New South Wales as it exists to-day. The service is still increasing in the number of persons and organizations served, in spite of the removal of numerous organizations that consistently show low dosage returns. At the present time a computer programme to eliminate all the calculations, and much of the clerical work, has been prepared and it is hoped to commence the use of this in the very near future. The results given show that, with improved equipment and techniques, industrial radio- graphers are tending to fall into lower accumu- lated dosage groups. In the discussion of the accuracy of Film Badges it is seen that there is little point in quoting an accuracy of better than 20%, particularly, in cases such as ours, where this is no control of the actual handling and usage of the films and the radiation to which the films have been exposed is only known approxi- mately. In closing it is indicated that a thermo- luminscent dosimetry system would be more accurate than a film badge one, but consideration of economics make it unlikely that a change to this system will occur in the near future. Further there is some doubt on whether the increased accuracy would really be worth the expense. References APPLETON, G. J., AND KRISHNAMOORTHY, P. N., 1960. Health Physics Addendum. Safety Series No. 2, Safe Handling of Radioisotopes. International Atomic Energy Agency, Vienna. 127 BRITISH JOURNAL OF RADIOLOGY, 1955. Recommenda- tions of the International Commission on Radio- logical Protection. B.J.R. Supplement No. 6, 4-10. Bropsky, A., 1963. Accuracy and Sensitivity of Film Measurements of Gamma Radiation. Part II. Limits of Sensitivity and Precision. Health Physics, 9, 463-471. Bropsky, A., AND KATHREN, R. L., 1963. Accuracy and Sensitivity of Film Measurements of Gamma Radiation. Part I. Comparison of Multifilm and Single-Quarterly-Film Measurements of Gamma Dose at Several Environmental Conditions. Health Physics, 9, 453-461. Bropsky, A., SPRITZER, A. A., FEAGIN, F. E., AND BRADLEY, F. J., 1965. Accuracy and Sensitivity of Film Measurements of Gamma _ Radiation. Part IV. Intrinsic and Extrinsic Errors. Health Physics, 11, 1071-1082. DEPARTMENT OF PUBLIC HEALTH, NEw SOUTH WALES, 1959-1967. Annual Reports, Radiation Branch. FLEISCHMANN, A. W., 1965. Radiation Incidents in New South Wales. Brit. J. Industrial Safety, 6 (72), 270-277. Gorson, R. D., SUNTHARALINGAM, N., AND THOMAS, J. W., 1965. Results of a Film Badge Reliability Study. Radiology, 84 (2), 333-345. GOVERNMENT OF NEW SouTH WALES, AUSTRALIA, 1957. Radioactive Substances Act, No. 5, plus Amendment, and the Regulations under the Radioactive Substances Act, 1957. New South Wales Government Printing Office, Sydney. HEARD, M. J., AND JONES, B. E., 1965. A New Holder for Personnel Dosemetry. A.E.R.E.—M 1178, Harwell. KATHREN, R. L., AND Bropsxy, A., 1963. Accuracy and Sensitivity of Film Measurements of Gamma Radiation. Part III. Effects of Humidity and Temperature during Gamma Irradiation. Health Physics, 9, 769-777. LANGMEAD, W. A., AND ADAMS, N., 1967. Investiga- tion of the Accuracy Attained in Routine Film Badge Dosemetry. Health Physics, 13 (2), 167-180. MENKER, R. F., AND DavErR, M., 1965. Evaluation of Film Badge Dosemeters for Occupational Radiation Exposure. Industrial Medicine and Surgery, 34, 700-704. RECOMMENDATIONS OF THE INTERNATIONAL CoM- MISSION ON RADIOLOGICAL PROTECTION, 1965. Publication 9, Section D, General Principles for Operational Radiation Protection, paragraph 112. Pergamon Press, New York. UNITED STATES DEPARTMENT OF COMMERCE; NATIONAL BUREAU OF STANDARDS (N.B.S.) HANDBOOK 78, 1968. Report of the International Commission on Radiological Units and Measurements (Coke): Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 129-133, 1968 A Tesselated Platform, Ku-ring-gai Chase, N.S.W. D. F. BRANAGAN Department of Geology and Geophysics Umiversity of Sydney ABSTRACT—An unusual sandstone platform consisting of patterned joint-blocks is described. Although reminiscent of columnar jointing, the ‘‘ columns ”’ do not continue vertically into the rock. Thin section examination shows little evidence of contact metamorphism. The patterns are considered to be due to metamorphic processes although no igneous intrusion crops out in in the vicinity ; however, there is a possibility that they could be of sedimentary origin. Columnar jointing in the Hawkesbury Sand- stone has been recognized at a number of localities, of which North Bondi and West Pymble (Curran, 1899; Morrison, 1904 ; Sussmilch, 1914; Osborne, 1948) are perhaps Well marked edge vy of pavement ye - region ™ Present | rae Location of Tesselated Pavement Ku-ring-gai Chase Scale: 1:19,000 approx. Fic. 1—Locality sketch map. best known. Following a query from Mr. J. Pierman of Sydney Teachers’ College, I visited an area in Ku-ring-gai Chase National Park adjacent to the West Head road (locality 1, Fig. 1). This area was studied by Campbell (1899), who recorded aboriginal carvings, but he did not comment on the unusual character of the sandstone. At least three separate but closely adjoining areas at this locality are covered by patterns reminiscent of columnar jointing. However, in most cases the “ columns ”’ do not appear to continue vertically through the rock for more than a few feet. The best exposed of the areas is an undulating platform approximately 500 ft. x 100 ft., immediately adjacent to the West Head road (Fig. 2). The other areas of comparable size lie to the east and north-east. There are smaller areas (a) west of the road at the same locality, and (b) on the Coal and Candle Creek road (locality 3, Fig. 1). Although the phenomenon may possibly be attributed to contact metamorphism, the out- crops are not noticeably hardened as at North Bondi, and thin section examination shows no sign of recrystallization of the quartz grains. Thin sections of altered sandstones close to intrusions at Gladesville, North Bondi, West Pymble, Bundeena and Hurstville show marked changes along grain boundaries of quartz which are not evident in any of three samples from the West Head road site, but incipient alteration of kaolinitic material is similar in all slides. No intrusive rocks have been found to crop out adjacent to the pavements, but there are several large lineaments which may be weathered dykes visible on the aerial photograph of the region (Broken Bay, N.S.W., Run 8, 236—5036)* trending approximately 30°. No dyke material has been found in these and there is no increase in the number of joints adjacent to the linea- ments. The nearest visible dyke, trending approximately 290°, crops out at locality 2, Fig. 1. The area immediately south of the * Photographs on this run have north points incor- rectly marked pointing south. 130 D. F. BRANAGAN Fic. 2—View of platform looking south-west. The elongate ‘‘ columns ”’ in the foreground are gradually replaced by uniform five-, six- and seven-sided blocks. A TESSELATED PLATFORM, KU-RING-GAI CHASE, N.S.W. pavements at locality 1 is a low-lying swampy area which could conceivably contain igneous material in a neck-like intrusion. The north-western edge of the main jointed platform coincides precisely with the edge of a channel sandstone. This channel is clearly 131 some suggestion of columnar development on the west side where only the ferruginous sand- stone occurs. Variations in the patterns in area 1 are shown iny big, Zand my Figs. 4 and 5. Phere is a clear change in dimensions and shape of the Fic. 3—Sandstone channel exposed in road cutting. The tesselated platform forms the upper surface of this sandstone. [Note—The drill marks formed during road construction should not be mistaken for columns. | There is evidence of considerable migration of iron through the channel sandstone. exposed in the main road cutting (Fig. 3), where it overlies a very ferruginous sandstone. The eastern edge is not so clearly exposed. Along the base of the channel a thin layer (maximum 3 in.) of soft clay occurs. Columnar jointing is not apparent in the rocks exposed on the east face of the road cutting, but there is patterns along the platform, possibly related to the position of the postulated heat source but also affected in part by the undulations of the surface and the character of the sandstone. Near the north-western edge of the channel, which is sharply defined by a low cliff line, the patterns appear to dip inwards towards 132 the channel centre. One area, where the sandstone has been contorted by slumping, shows no patterned jointing. The apparent restriction of the unusual jointing pattern to the channel sandstone east of the road suggests that the base of the channel may have been the locus of a sill-like intrusion, possibly related to nearby dykes. Heat escape could have been largely upwards, causing recrystallization of the overlying sandstone. D. F. BRANAGAN Conclusions There is no clear evidence of contact meta- morphism of the sandstone at the various localities examined, but such metamorphism is postulated despite the apparent lack of vertical penetration of the patterns. Spry and Solomon (1964) have dealt in detail with the possible causes of buchite formation adjacent to a basaltic intrusion and have pointed out the similarity of their altered sandstones to those Fic. 4—Typical pattern near the south-west edge of the platform. Width of the polygons varies between 1 ft. 6in. and 3 ft. in this area. The heavy iron-staining in the underlying sandstone may have been derived through chemical weathering of igneous rock, as is typical around the North Bondi intrusions. However, the clay seam underlying the channel sand contains quartz grains and mica flakes, indicating a sedimentary origin. West of the road similar patterns, less well- developed, occur in a sandstone bed strati- graphically below the ferruginous sandstone unit. There are both vertical and horizontal columns which cannot be easily related to a possible heat source. The similar jointed sandstone at locality 3 has no obvious source of alteration but is close to several strong lineaments (Fig. 1). A small irregular neck- shaped body could be present in the valley between localities 1 and 3 but no breccia outcrops have been observed. Similar areas yet to be studied have been noted further north along the West Head road. of the Sydney district. The absence of evidence of such metamorphism is one of the character- istics of the area herein described, and an origin somewhat akin to mud crack development cannot be rejected at this stage. The changes involved in development of such phenomena are a neglected phase of geology which deserve attention. A detailed survey is proposed so that the specific relations between column shapes and sedimentary properties can be studied. Mr. Erskine, Chief Ranger of the Ku-ring-gai Chase National Park, believes there are other similar areas within the park and is compiling a list of localities which will also be studied. It is fortunate that this interesting exposure lies within the National Park and is being preserved ; the road to West Head was, in fact, diverted for this reason. It is a park feature well worth a visit by geologists, but care is needed to preserve the surface from excessive wear. A TESSELATED PLATFORM, KU-RING-GAI CHASE, N.S.W. 133 Fic. 5—Typical platform. The well-defined elongate ‘‘ columns ”’ of Figure 2 become longer and less evident towards the north. The circular depressions common on the platform may have been artificially worn by aborigines as the sandstone is soft, especially in the centres of some of the equi-dimensional pattern Columns . at the northern end of the There are numerous large carvings on the platform. Acknowledgements I wish to thank Mr. E. Armstrong for prepara- tion of thin sections, Mr. A. Potts for printing of black and white prints from colour slides, Miss J. Forsyth for preparation of diagrams, and Miss S. Binns for typing. References CAMPBELL, W. D., 1899. Aboriginal Carvings of Port Jackson and Broken Bay. Mem. Geol. Surv. N.S.W., Ethnological Series No. 1. Curran, Rev. J. M., 1899. The Geology of Sydney and the Blue Mountains. 2nd ed. Angus & Robertson, Sydney. Morrison, M., 1904. Notes on Some Dykes and Volcanic Necks of the Sydney District with Observations on the Columnar Sandstone. Ree. Geol. Surv. N.S.W., 7, 241-281. OsBorNE, G. D., 1948. Note on the Occurrence of Tridymite in Metamorphosed Hawkesbury Sand- stone at Bundeena and West Pymble, Sydney District, N.S.W. Proc. Roy. Soc. N.S.W., 82, 309-311. Spry, A. H., AND Sotomon, M., Buchites at Apsley, Tasmania. Soc. Lond., 120, 519-545. Sussmitcu, C. A., 1914. Geology of New South Wales. Sydney. 1964. Columnar Quart. J. Geol. Journal and Proceedings, Royal Society of New South Waies, Vol. 101, pp. 135-136, 1968 A Note on Convex Distributions JAMES L. GRIFFITH Depariment of Pure Mathematics, University of New South Wales It is known that a convex function /(%) defined and locally bounded on the real line is necessarily continuous (Rudin, 1966, Th. 3.2, p. 60 ; Boas, 1960, p. 142 e seq.). Also, if a convex f(%) possesses a second derivative, then f')(%) >0. If, instead of functions, we considered distributions, there are (at least) three possible definitions of convexity which reduce to the ordinary definition when the distribution is a function. These are : (a) T’)>0, which has a meaning since distributions are infinitely differentiable ; (6) T(x+h)+T(x—h) —2T (x) >0 for all 4, which has a meaning if the distribution is defined over D; (c) T(% +h) +T(%)—Ao) —2T (%o-) =O for all x) and ho, where T(x )+h,), T(*%)—h,)) and T(x») signify the values of T taken in the sense of Lojasiewicz (1957) at the points %)+/5, %)»—hy and %, respectively. (In definitions (a) and (b) we understand T>0 to mean >0 for all o in D such that o(x%) >0 for all x. Considering first (a), we note that >0 for all positive » in D implies that for all » in D (7, 9)= | ola)aule where uw is a positive measure on the Borel sets on the real line (Gelfand and Vilenkin, 1964, oh. 1, p. 142). Since pu is positive, we may write [oman in the Stieltjes form [ecoao, where v(x) =| du. [a,x] Here we take a to be any real number less than the support of » and [a,x] to be closed. Then v(x) is an increasing positive function. Now (To) = = | ° o(x)do(s) x a _ o2)(x)dex { v(q)dq (using integration by parts). Thus in a distributional sense T (2) = S(2) where S= { " w(a)ag is a continuous function. From which we see that T=S+ax+b (a, b constants) (Friedman, 1963, p. 56). B 136 JAMES L. GRIFFITH We do not know whether S‘) exists as an ordinary derivative or not. However, it is easy to see that S(%-Lh) +S (x%—h) —2S(x) = [--%@a—f" v(q)dq>0. Thus S and T are distributions generated by continuous convex functions. Now suppose that 9>0 is in D. Then (T®,¢>=lim h-*(T(x-+h) +7 (x—h) —2T (x)),9(X)). h—o If (0) holds, then the right side of this equality >0. Thus T')>0, and (d) implies (a). The value T(% ) of a distribution I at a point %, is defined by Lojasiewicz as follows : Suppose that PE Neral 2) 12) ee oa, for all g in D, and that C is a constant distribution. Then EG Ce We assume that 7%) exists for every %). Then Lojasiewicz (1957), Th. 5.7 shows that T'(% ) considered as a function of % is a Baire function of class 1 and is thus measurable. Corollary of section 5.2 of the same reference proves that if T(%))=/(%,), then T(x) =/(«) in the distributional sense. So if we assume that S(% +h) +f (%—h) —2f (x) >0 T(%+h) +T(%—h)—2T (x) >0 in the distributional sense, which is the assumption in (0). Thus in case (c) T(*) again is equal to a continuous convex function. then References Boas, R. P., 1960. A Primer of Real Functions. GELFAND, I. M., and VILENKIN, N. Ya, 1964. Math. Assoc. of America. Generalised Functions, Vol. 14. Academic Press, FRIEDMAN, A., 1963. Generalised Functions and New York. Partial Differential Equations. Prentice Hall, Rupin, W., 1966. Real and Complex Analysis. Eaglewood Cliffs. McGraw-Hill, New York. Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 137-146, 1968 Geological Techniques* ALAN H. VOISEY ABstTRACT—Geological techniques are demonstrated by an approach towards the history of the growth of land masses from an original basaltic crust of the earth. The gradual formation of complex continents through the sub-areal decomposition of basalts and subsequent tectonism is proposed. Successive stages in development are illustrated by types of land mass existing at present, e.g. oceanic islands, and those in island arcs. The suggestion is made that vulcanism and tectonism are essential to the maintenance of life on earth through the supply of unstable rocks which provide new soil and energy through their breakdown under surface conditions. The word used for descriptive work on the earth’s materials in the 18th century was “geognosy’’. This study was defined by Abraham Gottlob Werner as the “Science which inquires into the constitution of the terrestrial body, the disposition of fossils (meaning both minerals and petrified organisms) in the different rock layers and the correlation of the minerals one to another ”’ Today some people are still inclined to accept this as the definition of geology. Under the name “ geology ’”’ suggested by De Luc, Werner would only recognise specula- tions about the origin and history of the earth but it was James Hutton who gave modern geology its start in his paper on the “ Theory of the Earth’’, read before the Royal Society of Edinburgh in 1785. Hutton here presented his ideas on the origin of rocks, the development of the earth’s crust and the pre-existence of older continents and islands from which the more recent land areas must have been derived. He likewise discussed the evidence for the previous existence of faunas and floras from which present types of life must have sprung. Hutton understood more clearly than his pre- decessors a number of phenomena such as the slow processes of subaerial denudation and deposition. He consequently introduced ways of thinking which do not appear to have been exploited by them. As Zittel (1901, p. 71) pointed out, the great feature which dis- tinguished Hutton’s theory and marked its superiority was the strict inductive method applied throughout. Every conclusion was based on observed data that were carefully enumerated. No supernatural or unknown forces were resorted to. Events and changes * Presidential Address delivered before the Royal Society of New South Wales, 5 April 1967. in past epochs were explained by analogy with the phenomena of the present age. Geology as envisaged by Hutton is really Earth History and consequently is related to our concept of time. Events follow one another in sequence. Each is related to its predecessor and its successor. Parts of a sequence are related as cause and effect. In the context of the availability of long periods of time it is usually difficult to find a beginning and even more difficult to foresee an end. It is possible to recognise a process slowing down or accelerat- ing. Extrapolation of observations in either direction has to be done cautiously. Data can be plotted just as if experiments had been carried out. Geological techniques therefore, involve both space and time without necessarily having recognisable limits. To illustrate this point let us consider a granite decomposing to a soil. The granite exposed at the earth’s surface breaks down slowly to a soil made up of quartz grains, clay, limonite and organic matter. The products of breakdown become stable as a result of the chemical and physical conditions existing on the earth’s surface at that place and over a certain period of time. The granite had been stable under conditions deep in the earth’s crust where it was formed, probably through melting of rock materials which them- selves had an earlier history. It was not stable near the surface. The geologist does not have to devise an experiment to show how the mineral feldspar in a granite breaks down to form clay. Indeed, the process takes a long time and cannot be conveniently carried out in a laboratory. The observation of the stages of breakdown from granite to soil gives a more complete picture of the nature of the chemical change than is 138 usual in an experiment of similar type because the intermediate products all exist at the same time. sir Charles Lyell’s “ Principles of Geology ”’ was described by him as “an enquiry how far the former changes of the earth’s surface are referable to causes now in operation’’. The uniformitarian doctrine developed by Lyell is just one application of our belief in the continuity of natural processes and in the operation of the laws of physics and chemistry which have been formulated and on which progress in our knowledge of science depends. TAHITI yeerenny Ww, oe Sei Ly ES: a ceaeees ty, su \ pppanans 5 Ne 17°40' § Wes etee wir Seite Gas SBB aBB8 eae aaa eae BBB aan =a =: Rae (Tied . Aa’ ‘ii ee: s in s i ‘ninth vues ai t cit BASALTIC VOLCANIC ROCKS CALCAREOUS CORAL REEFS ALAN H. VOISEY which the layered rocks were deposited and his his correlation of them by means of the contained fossils led to the formulation of “the law of super-position ’’ and provided the means of determining the sequences of events in the history of the earth. It is of interest to note that biologists have been able to confirm some of the findings of geologists by similar techniques—e.g. observing stages in the growth of some organisms. In their development these forms pass through adult stages of their ancestors—‘‘ the ontogeny recapitulates the phvlogeny ” Aine ss iN, Vi osee. mi “hae 149°20' W Fic. —Tahiti. Collection and selection of the data to be used in the attempt to work out a particular problem, and not infrequently its preparation for study, occupy most of a geologist’s working time. William Smith, an English engineer, carried out field observations over many years and was able to produce a geological map of England and Wales from his knowledge of the distribution of the rocks. His recognition of the order in Dr. M. K. Hubbert (1963, p. 375), in his Presidential Adress to the Geological Society of America pointed out that “‘ the evclution of science is, in fact, not a progression from the simple to the complex—but quite the opposite. It is a progression from the complex to the simple ”’ In geognosy the initial collections included a wide variety of forms. Geologists in making GEOLOGICAL TECHNIQUES their observations had to contend with a chaos of land-forms, configurations of land and water and so on. From this great mass of material they have managed to decipher much of the history of the earth. Many geological techniques for dealing with selected data are not now peculiar to the subject but are the same as those of the other sciences, KOLOMBANGARA I. oe Seunsean “| REEF LIMESTONES MODIFIED FROM COLEMAN ef a/ 1959-62 139 distant past it is possible to recognise orderly sequences of events leading to the formation of the various rock types which make up the land. By reversing this sequence and observing the combinations of rocks, geological structures and land-forms we can extrapolate backwards in time. The complex continents may be dissected 40 20 30 | NEW GEORGIA I. MILES TUKAI I. fig 2a Fic. 2a—New Georgia, Solomon Islands. even to the extent of mathematical representa- tion and interpretation. The real differences between geology and other disciplines lies not in the methods used but in the problems which each attempts to solve. The history of the land masses which now rise above the oceans constitutes perhaps the most important geological problem which may be approached by the application of what may be called geological techniques. By noting processes going on at the present time on the earth’s surface and by considering those known to have taken place in the not too and a series of stages each more simple than the previous one may be recognised, with a simple volcanic island seen as possibly the earhest land-mass. Analogous stages in continental development may be selected from existing islands today. —?—?—? = Dark well bedded Chert, Wagonga 5 lavas, Volcanic breccia Wagonga Formation 34 and tuff. Beds Se —_——________---——————___ Older Series Wagonga Series Wagonga Beds BS sa Slate phyllites boulder ae beds arenites and some Bogolo B chert. Formation & E 4) — ? — ? — Junction not specifically defined. 148 the N.S.W. State Geological Survey to regard the upper limit of the Wagonga Beds to be the chert-greywacke boundary, this being apparently based on the assumption that the undifferentiated greywacke sequence overlies the cherts unconformably. No evidence for or against an unconformity has been seen in this area and it is the author’s belief along with other workers (M. A. Etheridge, P. F. Williams, and R.G. Wiltshire, personal communication) that LOCALITY MAP LEGEND OF AREA C. 1) Ly WILSON In this paper, it is proposed to deal with the © general geology of the area and to subdivide © the undifferentiated sequence into two forma- tions; a detailed description of the structure will be described elsewhere. Co-ordinates are — given for field localities from the Bega Geo- logical Sheet. The five figure numbers retem to specimens and sections in the collection of the Department of Geology and Geophysics, University of Sydney. Tertiary Basalt Ce aed Tertiary Sandstone Ka Cretaceous Mt. Dromedary Monzonite Complex ue Upper Devonian Sediments ey fs okew iat, Ye. 5a) if me ie haere! Upper Devonian Volcanics eee ae Slate and Arenites Moruya Granite NEW SOUTH WALES Data from Bega Geological Sheet prepared by the N.S.W. Geological 1965, Canberra @ Survey Ordovician Sediments ©— pte ont te? z Cg Chert, Basic Volcanics we <) . . . . . . e . . . . . MONTAGUE ISLANO eal vol. ay See vie: Ls) iat itel cal ce me mede lg] NAROOMA BiGan to the north and south of the Narooma area the cherts and greywacke sequences are possibly conformable. The above nomenclatural history for the name ‘“‘ Wagonga’”’ is summarised in Table 1], and there appears to be no justification in assigning these rocks to the Cambrian. It is also evident that the name has been inadequately defined with its use in several different senses at different times even since the introduction of the Australian Code of Stratigraphic Nomen- clature. Stratigraphy The stratigraphy of the sedimentary rocks in the Narooma area is summarised in Table 2. The pre-Tertiary sedimentary sequence has been intensely folded and it is not possible to measure the stratigraphic thicknesses of any formation with any degree of accuracy (cf. Cloos, 1947). The thicknesses given in Table 2 are those estimated in th: present type sections. Out- crop of these older sedimentary rocks is generally very poor and the depth of weathering and THE GEOLOGY OF THE NAROOMA AREA, N.S.W. associated secondary alteration is as great as 800 ft. in most parts of the area. This is possibly because there has been a continuation of the pre-Tertiary, or even earlier, weathering. TABLE 2 Age Formation or Rock Thickness ape Quaternary Sand, alluvium Variable Tertiary Sandstone, gravels 20’ + ( Undifferentiated Undifferentiated | greywacke and Ordovician < pelite 3000’ + Sequence | Wagonga Formation 1200’ + | Bogolo Formation... 600’ + BoGOLo FORMATION The Bogolo Formation consists of slates and phyllites with subordinate boulder and arenite beds, and chert lenses (see Plate 1, Figure 1). It is extensively exposed along the shores of Corunna Lake and on the coast from the entrance of the Lake to the Glasshouse Rocks. The type sections lie between grid references 15902650 and 15772379 on the coast and between grid references 14002279 and 14002526 on the shores of the lake. The slates and phyllites are moderately fissile and occasionally possess a strain slip cleavage. They vary in colour from light green to grey when fresh, and from yellow to light green to purple when weathered. They are generally fine-grained and are composed of white mica with subordinate pale green biotite and suartz. The quartz (up to 15%) occurs as fine-grained recrystallised aggregates or as detrital grains elongate in the plane of the foliation. The arenites (in the sense of Pettijohn, 1957) are light grey or brown in colour, are generally discontinuous and are commonly found asso- ciated with ‘‘ boulder beds’. They are usually 2 inches to 8 feet thick and are laminated due to variation in percentage of matrix material. The arenites have at least 80°% detrital quartz, occurring mainly as angular and rounded grains of 0:3 to 0:6mm. across. Feldspar (19%) also occurs in a white mica matrix, with occasional blades of a very pale green biotite. The cherts of this formation are generally small lenticular, intensely folded bodies com- pletely enclosed by slates and phyllites. These chert bodies are usually massive and similar to those described below in the Wagonga Formation, but may contain thin interbedded grey and red pelite layers alternating with 149 layers of grey and black chert, no greater than 2 inches in thickness. The lenticular nature of the chert is believed to be a sedimentary feature rather than tectonic. The name boulder bed was applied by Brown (1933) to the occasional layers of elongate “boulders” set in a slate, occurring at Bate- man’s Bay and Narooma. The “ boulders ”’ are generally arenites similar to those described above, and commonly have a shape approximat- ing to a prolate ellipsoid with their major axes varying from less than 3 inches to 3 feet in length. The boulders are generally elongate in a direction parallel to the local fold axis and are strung out along the lithological layering as disconnected pods, although some are joined laterally to their adjacent boulder by a narrow neck, composed of the same _ material. Individual bedded units in association with the boulders, are either lenticular or consist of a series of dislocated blocks, which lie, and are commonly parallel to, a layering that has formed during folding. Many of these boulders are probably related to this deformation and are boudins (Lohest, 1909) formed in a series of interbedded pelites and arenites. On the other hand some boulders are deformed conglomerates. THE WAGONGA FORMATION The Wagonga Formation comprises a group of lenticular chert and volcanic units typically developed along the coastal section of Wagonga Head to the Glasshouse or Waramba Rocks, and in the vicinity of the Wagonga Trigonometrical Station. The type section locality may be found along the Wagonga River from grid reference 09002946 to grid reference 10472951. The two distinct lithological groups will be discussed separately as (1) the cherts and (2) the volcanic rocks. (1) The Cherts In the west of the area, two distinct lenticular chert layers have been distinguished. The easternmost layer adjacent to Corunna Lake consists of two main rock types: a hard massive black and grey bedded chert with beds varying from 4 to 2 inches in thickness and a highly folded massive grey bedded chert, varying from % to $ inch. Between adjacent chert beds are fine partings of a light grey or white pelitic material, which in most outcrops has been differentially removed by weathering. The westernmost unit, which is narrow at Corunna Lake, thickens to the north of Ohlsen’s Creek where it is the predominant rock type in the hinge of the major fold. The rocks 150 making up the southern section of this unit are composed of fine-grained siliceous beds varving in thickness from } to 6 inches. Each bed consists of a dark compact chert base, eradually becoming lighter towards the top and terminating in a white or pale grey friable micaceous layer. To the north of Ohlsen’s Creek these pelitic cherts are only found to a limited extent. Much of the chert found in the hinge region is similar to that adjacent to Corunna Lake. Also interbedded with these cherts, are rare thin beds of red jasper and thin layers of carbonaceous slate. The cherts on the eastern limb of the major anticline extend as far south as the Glasshouse Rocks. These also consist of the massive dark grey and black chert bands up to 20 feet thick together with the finer laminated cherts. Related to these are thin layered grey to white pelitic cherts similar to those found on the western margin, especially in the vicinity of the Wagonga Head. The thin laminated grey to white pelitic chert consists of a mixture of secondary white mica and quartz. The laminations are defined by a series of white mica-rich layers, varying from 0:04 to 0:25 mm. in width, within which may be small veins and lenses of recrystallized quartz. The dark laminae are rich in lmonite and often mask the white mica as in 31164. The black cherts are generally unlaminated and are composed of carbon, fine recrystallized quartz and minor quantities of muscovite. Because of a metamorphosed condition, original microstructure in the rocks is often masked by recrystallization. Within the carbonaceous cherts small “ windows ”’ of clear recrystallized quartz are commonly found. These are either elliptical or spherical in shape and are believed to be the Radiolaria mentioned by W. R. Browne (In David, 1950). These structures consist of either spherical bodies with rims of fine recrystallized quartz and cores of carbon, or spheres of recrystallized quartz with bounda- ries gradational into the fine-grained chert matrix. There is no positive evidence that these small windows of quartz represent Radio- laria, for no signs of radiolarian or sponge spicules were observed. Alternatively these structures may be interpreted as small siliceous concretions. The third group of cherts makes up the largest proportion of the sequence The rocks consist of very fine-grained aggregates (less than 0-:1mm. across) of recrystallized quartz C.J, WILSON and minor quantities of mica intersected by — numerous discontinuous veins of quartz. It is considered that these rocks possibly represent recrystallized chalcedonic cherts. Quartz veins are ubiquitous, being developed | throughout all the chert beds, especially within the more siliceous members. In most rocks at least two generations of quartz veins may be observed. They are frequently parallel to prominent superimposed structural surfaces such — as an axial plane cleavage or may occur as numerous, irregular, intersecting, fine-grained, recrystallized quartz veins. (2) The Volcanic Rocks These consist of highly deformed lavas, breccias and tuffs, the outcrop of which, on the western limb of the Narooma fold, is charac- terised by two prominent layers separated by a chert lens. These two layers of volcani¢ material converge to the north of Ohlsen’s Creek to form one unit which passes into the hinge of the fold where it becomes interbedded with finely layered cherts. In the east, a nearly continuous layer extends northwards from the Glasshouse Rocks to Kianga Lake. No pyroclastic rock or lava has been found adjacent to the underlying formation on the eastern limb of the fold. Despite extensive regional metamorphism, it is possible to recognise three varieties of primary igneous rocks within the deformed volcanic sequence. These are massive igneous rocks, pyroclastics and pillow lavas. In the latter, the pillows occur as 3 inch to 3 foot elliptical bodies differentially weathered around their margins. Fresh specimens of individual pillows and associated margins can rarely be found on the coast or inland. Amygdales are present in most of the pillow lavas having either a spheroidal or tabular shape, and contain secondary fillings of chlorite, muscovite and calcite or alternations of all three minerals (30251), together with occasional quartz grains in irregular cavities of approximately 0-5 mm. to 2-8mm. across. Below the layer of pillow lava at the north end of Surf Beach, there are a number of thin injections (approximately 2 inches wide) from the pillow lava into the underlying unconsolidated volcanic tuffs. The lavas are either porphyritic or holo- crystalline, the latter variety now consisting of equidimensional feldspar crystals set in a chlorite-rich mesostasis. The porphyritic lavas contain phenocrysts of albite (An,), pseudo- morphs after a more calcic plagioclase, and ferro- magnesian minerals, set in a very fine mesostasis 151 THE GEOLOGY OF THE NAROOMA AREA, N.S.W. VONOOY, ae GVH VYONODYVM ANiOd VONVIN 5 ve ee ANAW TVO'¢2- eoe0e a = CO eae Ne ee eis oe ‘a Sty ee ty ve 0 eo & =i Lee e Cia ers @ |B BOE > é ee 5 2 ae] ANS - e e aS r g BARC 3 oe Sl eee Meee Se NN. | NR rae caiers one ee tar S| \ BE i=) Oo [e) KK Nr m OOO8ES QL ‘oDALMENY "ne? KIANGA POINT WAGONGA li | | Y GLASSHOUSE | Cp WARAMBA | BS) Sener | a ESOS | 28) 28 26 26) GEOLOGICAL MAP OF THE NAROOMA AREA EXPLANATION 44 QUATERNARY alluvium sand and sit oligomictic congiomerate sands TERTIARY and unconsolidated sand Porphyritic_micromonzonite RETACEOUS mm te REN EROS GAT’ and monzonit ROCKS DEVONIAN (7) acid and basio intrusions and lavas 22 22 UNDIFFERENTIATE Greywacke and polite JUNDIFFERENTIATED B WAGONGA chert ORDOVICIAN FORMATION volcanics Yj} SEQUENCE GOLO pelite and quartz arenite oy FORMATION with small chert lenses Y, ny Oy NEE strike & dip of lithological tayerinay bedding S. Ka trend & plunge of axis of By fold. curve indicates > a>: XK strike of vertical lithological layering layering Sy 2 sense of closure & strike of axial plane. 35 , ON strike & dip of Sp trend & plunge of B2 folds & boudins. a] strike of vertical So lane geological boundaries, dashed are apptoximately located. scale Sy FS —————ore Ped type section ». 6 dealt pe er fault rn 19000 5 10. 14 16 ‘MSN ‘VaNV VNOOUVN AHL AO ADOTORD AHL TST 152 of chlorite, biotite, muscovite, quartz and occasionally, a few grains of albite. These are stained with limonite, which is generally a weathering product. No primary flow structure has been’ recognised, although secondary metamorphic minerals are frequently aligned into a rough parallelism in a superimposed slaty cleavage. Other lavas, such as those at the south end of Surf Beach (grid reference 15662925), now consist of a fine-grained weakly foliated rock within which are numerous dark green and brown elongate “ bodies’, ranging in size from less than $ inch to 7 inches in length. They are commonly elongate and flattened in the plane of foliation and plunge gently to the north west. Hobbs (1962, Figure 6b) refers to this rock as a conglomerate. Two varieties of these “bodies ’’ are contained within a matrix of fine-grained biotite, muscovite, quartz and much goethite. The first type resembles a quartzite and consists of fine recrystallized quartz, muscovite and light green biotite. The second type is more abundant, consisting of elliptical rounded and angular mosaics of light green chlorite set in a very fine mesostasis of goethite, quartz, chlorite, green biotite, and white mica. In her collection of rocks from the Narooma area, housed in the Department of Geology and Geophysics, University of Sydney, Dr. I. A. Brown has called several of these elongate masses, “‘ boulders” (28249, 28251, 28258, 28259). In the writer’s opinion, this rock is considered to be an amygdaloidal lava flow and the “ boulders’”’ represent deformed quartz- filled cavities and recrystallized glassy areas. The chlorite-rich “ boulders’ are amygdaloidal and the amygdales are often surrounded by a very fine mesostasis which may once have been a glass, for it is intersected by a number of curved cracks which could possibly represent perlitic cracks, now filled with limonite and hematite. Volcanic breccias with a light brown weathered matrix are found along the northern cliff face of Surf Beach. Here they consist of ellipsoids or angular shaped masses which vary in length from + to 6 inches, being elongate in the plane of the foliation and parallel to the local fold axis. In thin section they consist of albite, white mica and chlorite. The breccias are commonly associated with the pillow lavas, an association which may suggest they are really pillow breccias formed by slumping and fragmentation of an unstable pile of pillows and tuff, C. J: L: WILSON THE UNDIFFERENTIATED GREYWACKES The sequence outcropping along the western margin of the area and in the northeast comprises an unknown thickness of thinly bedded, quartz- rich clastic sediments and minor pelites. The presence of ubiquitous graded bedding and an absence of cross bedding in the clastic material has allowed these rocks to be classified, using Packham’s classification (1954), as members of a greywacke suite. The greywackes along the coastal section are light brown to buff coloured, and inland they are commonly a light yellow-brown. The beds of greywacke vary from 6 inches to 6 feet in thickness. They are generally poorly sorted, medium to fine-grained rocks consisting of fragments of quartz, feldspar, muscovite and biotite set in a fine-grained recrystallized matrix of muscovite and quartz. The quartz (25 to 75°%) occurs as angular to sub-rounded detrital fragments, as large grains containing numerous subgrains, and as fine- grained recrystallized fragments. In the coarser greywackes, the inequant grains have their long axes lying parallel to the plane of bedding (e.g. 31168). The feldspar is commonly plagio- clase, which comprises up to 29% of the total rock volume and is most abundant in the medium to fine-grained rocks, being rare in the coarse sediments. The plagioclase, An,, is generally fresh and may also be found in association with small grains of microcline. Detrital plates of muscovite and biotite as well as a small percentage of pelitic rock fragments (e.g. 31169) are also present. The pelites are rarely more than two feet thick and are generally subordinate to the greywacke beds. They are fine-grained, and consist of muscovite and quartz, together with occasional ragged, weakly pleochroic biotite plates. Generally they have been significantly altered by metamorphism and it is not certain whether the grain size now seen is the original or due to metamorphism. Sedimentary structures are common and include graded bedding in the greywackes, current bedding in the pelitic rocks, together with sole markings, flame structures, and bedded units containing numerous intraformational mudstone fragments. These sedimentary struc- tures only give the local facing of a bed. From the limited evidence available, the orientation of the formations within the Narooma fold are thought to be the right way up. THE GEOLOGY OF THE NAROOMA AREA, N.S.W. DISCUSSION AND CONCLUSION The arenites and pelites of the Bogolo For- mation appear to be conformable with the overlying Wagonga Formation. The undifferentiated greywackes and pelites are lithologically distinct from the underlying Wagonga Formation. Nevertheless, there is no evidence for or against an hiatus between these two units and it is considered that they may be conformable. Brown (1928) describes a similar chert- greywacke boundary at Bateman’s Bay, as being unconformable and on this basis splits the sedimentary sequence into Upper Ordovician and Cambrian. A Cambrian age for these sediments is now open to question by the discovery of a graptolite of a (?) retiolid character by Dr. A. A. Opik, in shale from immediately above a chert layer. This was quoted by Sherrard (1962) but the specimen has since been destroyed by fire at the Bureau of Mineral Resources, Canberra. If this was a retiolid graptolite, then the chert sequence may be upper or middle Ordovician in age. Until more definite proof is available, the age of these sediments will still be open to question. The rocks of the Narooma area appear to be con- formable and as such, could be Ordovician. It is suggested that the presence of the persistent bedding and associated sedimentary structures in the greywacke may be explained in terms of turbidity current deposition in a geosynclinal environment. Such an environ- ment would also be compatible with the formation of the cherts and the presence of basic volcanics. The cherts, and especially those of the Bogolo Formation, may possibly represent a chemically precipitated deposit in a closed basin. The chert of the Wagonga formation probably represents a major accumulation, being inter- rupted by minor influxes of pelitic material and the extrusion of submarine lava flows and the deposition of tuff. This volcanism could have served as a major source for the precipitated silica. The sedimentary sequence found in the Narooma area is probably part of the Lachlan Geosyncline (Packham, 1960) which in main- land eastern Australia is dominated by quartz- rich greywacke and pelitic rocks. Sedimenta- tion would have been brought to an end by the Benambran Orogeny which is probably responsible for the major deformation of the area and the Narooma Fold. The fold is a large anticline plunging from 10 to 30 degrees to the NNW. Cc 153 THE TERTIARY DEPOSITS These occur as isolated cappings on the small hills and cliff tops adjacent to the coast. Two principal rock types have been observed, an oligomictic conglomerate and a ferruginous sandstone, both occurring some 90 to 100 feet above the present sea level. There are no microfossils in these rocks or any other indication of their relative age, so they have been tenta- tively assigned to the Tertiary on a basis of similarity to deposits found further north (Brown, 1925). The oligomictic conglomerates typically occur at grid reference 15733055 and are composed of angular fragments of chert varying from + inch to 2 inches across set in a matrix of partially cemented ferruginous quartz sandstone. Other minerals found within the sandstone include small rhombs of calcite and grains of tour- maline, zircon and magnetite. Distinct current bedding may be observed in the finer layers and bedded units usually vary from 6 to 18 inches in thickness. The complete absence of any marine Fora- manifera and the abundance of small calcite rhombs tends to suggest that these rocks are Shallow fresh water deposits, that have been deposited within a closed or semiclosed basin separated from the Tertiary shoreline by a low barrier. QUATERNARY The Quaternary System is represented in the area by river alluvium and recent unconsolidated beach sand deposits. The latter are generally bar-type deposits found between the coastal headlands and consist of two main types of sand. The higher and apparently older deposits consist of leached incoherent quartz sand with varying amounts of organic material. These older deposits also contain many lagoons now filled by fresh water swamp or estuarine sedi- ments. The younger Quaternary deposits are mainly the present day sand beaches that connect the rocky headlands, consisting of fresh quartz sand free of any organic material. Large recent sand accumulations also occur at the eastern end of the Wagonga Inlet in the vicinity of Narooma township. Igneous Rocks There have been three major phases of igneous activity in the area. These phases and the major rock types they produced are summarised below : 154 1. Devonian (?) ; (a) Fine-grained acid intrusive rocks. (0) Fine-grained basic intrusive and extru- sive rocks. 2. Permian (?) ; Intrusive trachytes. 3. Cretaceous ; Intrusions associated ‘““Shoshonite Suite ’’* Dromedary Complex. the Mt. with of the DEVONIAN (?) IGNEOUS Rocks The Acid Rocks. These occur as dykes intruding the deformed sediments and vary from 9 inches to approximately 100 feet in width ; individual dykes are seldom traceable for more than 500 feet. They are composed of a fine-grained, white quartz-rich rock, porphyritic in both quartz and _ plagioclase. The quartz (40°%%) is commonly intergrown with fine anhedral potash feldspar, both in the groundmass and as small spherulites. The plagioclase phenocrysts (79%) occur as prismatic and tabular crystals (approximately 1 x 0:5 mm. across) ; their composition ranges from An, to An,. Secondary alteration of a number of dykes has resulted in the conversion of much of the orthoclase into fine white mica. The Basic Rocks. These are composed of both intrusives and a lava together with breccias, which unconformably overlie or intrude the folded sediments but predate the Permian and Cretaceous intrusions. The assignment of these rocks and acid volcanics to the Devonian is based partly on these stratigraphic relationships together with their similarity to the highly altered basalts, spilites and rhyolites of the Eden district (Brown, 1931, 1933). Small, light green, well jointed and very weathered, epidotised basic rocks occur through- out the area. Two good examples of such rocks are found as a basaltic dyke at grid reference 12672960 and an amygdaloidal basalt out- cropping at grid reference 104267. The dyke material has an intergranular texture and consists of plagioclase (and pseudo- morphs of chlorite), titanaugite, chlorite and clinozoisite, with accessory ilmenite, leucoxene and pyrite. The border phase of this dyke (e.g. 31186) exhibits a very pronounced vario- litic texture consisting of titanaugite and interstitial chlorite. The plagioclase occurs as prismatic laths approximately 1mm. long and is now generally completely pseudomorphed by a light green chlorite. The titanaugite has also been extensively altered and now consists of f a Using the terminology of Joplin, 1964. CL) wilson small remnant leucoxene-coated grains, approxi- mately 0-4mm. across, which are angular or prismatic in shape being separated from one another by thin aggregates of chlorite. Clino- zoisite is ubiquitous, occurring as small aggregates or as individual grains approximately 0-1 mm. across. The lava (e.g. 31156) is mineralogically identical to the epidotised basaltic dyke, except that the albite has not been completely chloritised and is present as elongate laths of approximately 0-8 to 0-5 mm. in length. This lava is also characterised by small spherical amygdales varying from 0:4 to 2:5mm. in diameter. These amygdales are generally filled with anhedral grains of clinozoisite (0:1 mm. across) together with large plates of albite or very fine chlorite. PERMIAN (?) IGNEOUS ROCKS This group of intrusive rocks postdates the folding of the area and predates the Cretaceous rocks, with one of the latter apparently intruding the former at grid reference 10882601. No relationship between these and the Devonian rocks has been established. The tentative assigning of a Permian age to this group is on the basis of a magnetic survey. The trachyte dykes are the only rocks in the area to consis- tently show a negative magnetic polarity in comparison to a positive polarity in all other rocks. Although several occurrences of negative polarities have been reported from igneous rocks of the Tertiary period these are ruled out by the fact that the dykes appear to be intruded by the Cretaceous intrusions and are uncon- formably below the supposed Tertiary deposits. A number of dykes consisting of trachyte occur throughout the area together with a larger intrusion at the north end of Surf Beach at grid reference 15553000. This intrusion appears to consist of two small plugs connected by a narrow discontinuous sill, along with two very weathered dykes. The contact of the intrusions with the volcanic sequence is indeter- minable because of poor outcrop, but the chert-intrusion contacts are very clear. Dr. I. A. Brown has collected several specimens from this contact and refers to them as the “matrix of pillow lava’’, (Specimens 28262 to 28264). It is considered that the intrusions are so distinct in composition and magnetic properties as to justify separating them from the deformed volcanics. Two characteristic trachytic igneous rocks may be recognised in the area. One is por- phyritic with an orthophyric groundmass and — THE GEOLOGY OF THE NAROOMA AREA, N.S.W. the other has either an intersertal or pilotaxitic texture. In both types of rock the predominant feldspar is potassic with occasional crystals of plagioclase (An,). The interstitial material is generally authigenic chlorite, opaque iron oxides, and varying amounts of carbonate and occasion- ally quartz. In the porphyritic rocks potash feldspar phenocrysts, which vary from 0-7 to 2mm., are commonly heavily carbonated con- taining cores of white mica. THE CRETACEOUS SHOSHONITE SUITE A number of the dykes and two small stock- like bodies or monzonitic satellites found in the area appear to be related to the Cretaceous monzonite suite of Mount Dromedary (Evernden and Richards, 1962). The Dykes Other than those in the vicinity of Ohlsen’s Creek (see below), the dykes are generally too weathered to obtain fresh material for thin section examination, except for a vogesite which occurs at grid reference 16002392. This dyke is porphyritic in hornblende and minor quantities of weathered plagioclase. THE MONZONITIC SATELLITES Two such intrusions have been found and these are similar to the Monzonitic Satellites described by Boesen (1964) to the south and west of Mount Dromedary. A small intrusion of micromonzonite outcrops to the south of Corunna Lake at grid reference 133219. This intrusion has been described by Purvis (1965) and is very similar to part of a larger body which outcrops in Ohlsen’s Creek at grid reference 103260. The rock is locally inhomogeneous but is monzonitic in composition, consisting of porphyritic micromonzonite and monzonite. PORPHYRITIC MICROMONZONITE In hand specimen this is a fine-grained rock varying from grey to dark greenish-grey with distinct phenocrysts of hornblende and _ less commonly pyroxene. The size of phenocrysts varies considerably throughout the intrusion, varying from 1 to 4mm. and these phenocrysts are frequently found aligned sub-vertically. A similar arrangement of the long dimension of xenoliths of country and igneous rock is present indicating vertical flow during intrusion. The porphyritic micromonzonite has variable quantities of hornblende, clinopyroxene and occasionally zoned plagioclase. The ground mass is a very fine-grained mass of potassic feldspar within which is included fine pyroxene, plagioclase and biotite, together with accessory magnetite, pyrite and apatite. 155 The plagioclase is confined chiefly to the groundmass as small euhedral prismatic crystals less than 0:1 mm. in length. Phenocrysts also occur as euhedral crystals and as fragments with a variation in size from 2-2 x 0:5mm. to approximately 0:3 to 0-1mm. The average composition of the plagioclase is andesine with a range of Ang, to Angg. Alkali feldspar is commonly confined to the groundmass as very fine-grained granular crystals and rarely occurs as _ phenocrysts. Very small laths of carlsbad-twinned orthoclase (2V 70°) are to be observed intergrown with pyrite (e.g. 31182), apparently formed by late crystalization of locally concentrated alkali-rich portions of the magma. Hornblende may occur: (1) as primary euhedral or subhedral phenocrysts or fractured, embayed and corroded fragments; (2) as a reaction product of clinopyroxene. The pheno- crysts of primary hornblende occur either as large (5 X 0-5 mm. to 0°3 x 0-1 mm.) euhedral crystals or as small glomeroporphyritic aggre- gates. The hornblende is commonly zoned and may contain small inclusions of pyroxene, plagioclase or magnetite. It is generally moderately pleochroic, as in 31158, with: xX = yellow CSL oy olive Lo ZL brown 2V — ve The second type of hornblende is generally a reaction product formed by an almost complete replacement of the clinopyroxene parallel to the pyroxene cleavage (e.g. 31179, 31183). This hornblende has a pleochroism from greenish yellow to deep olive-green. Il ll X = yellow A—Y—0). Basically, our problem is to determine, for a fluid which is incompressible, inviscid, irrotational and without surface tension, solutions of Laplace’s equation (equation (5)), subject to non-linear boundary conditions on the resulting unknown free surface y=/(x,t) (equation (6)), which satisfy the given initial conditions (equation (9)). The lack of linearity “ deprives one, for example, of the mathematical tools of superposition of solutions ; expansion in eigenfunctions or use of Green’s functions is not possible ” ({16], p. 462). The Infinitesimal-wave Approximation The underlying principle of this approximation is to reduce the degree of difficulty of the problem by use of an approximation which replaces the non-linear equations and boundary conditions with linear ones. The original formulation is thus replaced by another for which the solutions are approximate solutions to the original problem under certain circumstances consistent with the geometry of the configuration. (A comprehensive account of the theory of approximations is given by Wehausen and Laitone [16].) For our purpose it is sufficient to obtain superficially the well-known results of “ linearized ”’ (first-order) theory which are applicable to a special class of problems involving small disturbances and which neglect terms of second and higher order. If the motion is such that the elevation of the free surface y=f/ (x,t) is always a small displacement from the initial position y=0, we obtain the following initial value problem 020 070 ’ en ays FAP ar ean ee en ren DR rer (5’) do ae j= Bd O_O ate Se i heater eta (6’) 09 _of aa ay ot Oley — OF 5 Sau ae ert eee ei es (7’) 09 _OG__ x ; oe oe lu SO SAY SOV) We eee eae es taes: crete (8’) Pras OG == (Vin ——- Oe WOT ha Oi Aycterite e cosueesieitsueieta dv Re alelee s aidcaie Genii S o-ebec (9’) Solution of the Problem (i) General Discussion The problem posed by equations (5’)—(9’) is now a linear one. Hence, the “ pressure ”’ problem appropriate to the boundary condition (6’) and the “‘ wavemaker ”’ problem specified by equation (8’) are independent and can be superimposed. Solutions to these problems have been given, 174 Jae ohs JEON independently, by Miles [12] and Mackie [10]. For both the pressure and the wavemaker problems, solutions may be obtained by a double transform method using an even Fourier transform in x and a Laplace transform in ¢ [9]. If the respective solutions for /(x,¢) to the pressure and wavemaker problems are denoted by Fi(%,t) and f,(x,t), we have ie 6 F AC | s*thk 3 i we ee Uo (10) fo(R,s) = — sera U(a,s)e—**da ; | where f(k,y,t)= -{" AGL) COS RXAG and flosy.s)= f° janie" dt. 0 Taking the inverse:Laplace transform of equations (10), we find = Dea 2 Woe k,t)=-. |- k, k(t —) dt? ee 11 Alks—=_ale | Plbse sin veklt—a)er (11) t fo(kt)=— V (k,t) cos 4/gk(t—7) dr. | ne Sh ae eee (12) where Ven= | Ula tjenda. | 0 Thus, 0 Le _ ef, plod) Sveeeaceee) oy Git (13) provided oy P(RA)=V(R,b) ake. ool ee (14) By virtue of equations (13) and (14) we may restrict our attention to either the pressure problem or the wavemaker problem. If, for example, we consider in detail the solution of the wavemaker problem appropriate to a given velocity distribution U(y,t) (equations (12)), then, corresponding to the pressure distribution obtained from (14), we find from (13) the solution to that particular pressure problem. Taking the inverse Fourier transform of (12), we find t ros) oe) fo(x,t) = — = | ae | U(a,t)da \ COS kx COS 4/ek(t—Tlen “dts eee (15) 0 0 0 Using the result ([4], p. 15) for Re B>0 oe ry 1 y? xe—®* cos xydx=— ,F,(1;4;-— = Ie ( i) where ,F,(a;c;z) is Kummer’s confluent oc function we have, from (15), Lope ie) ee oie Flt) =I ae [* Ut — Abb A(a—ix) | ° a+ix 1fa| Le, 4(a+7x) de Equation (16) allows the determination of the free surface profile due to a wavemaker of general form U(y,t). INITIAL VALUE PROBLEMS IN TWO-DIMENSIONAL WATER WAVE THEORY 175 (ii) The Free Surface Profile as a Power Series in g Using the series where equation (16) becomes 1 oe) (—g)” t : oo) 1 1 Alel=—= > omy | _ taaynde \ Ven) ant eae Tarte Say 0 Equation (17) agrees with a previous result [9] for the shape of the free surface, as a power series in g, due to a wavemaker U(y,t). (iii) The Asymptotic Expansion of ,F,(a;c;z) For large values of | z| we use the result ([3a], p. 278) e is) y, alae et a2)» 4.0(| 2 [2-8 -2) 14 (a;¢;2) ~ [T(c—a)\ z ] n=o n' I(c) ZeA—c au (c—a),(1—a),, —n 2 ei—C—-N—1! rea = a 2-"-+0(| ez \) Pietcuge—- ee tetor lim 2-0 5-1 are 2 <7: NO, 1, 2) os, * ee Pelee wate ees (18) =—1 for Imz<0 gt? Thus, for large values of —-=———., we have 44/(42 +x?) 1 een Sa 1 pest dl a—1x BT a oa\\ tact ia (eorexer Na tet tS 09 \ ) | J 2 (a —2%) \ g —ix HIN gy Lix M 3 92n ; : ay n n=O Particular Results (i) A velocity distribution consistent with the approximations of the linearized theory used is OA 1) aE) OM Reta rergatens alana ers eerie (20) where T(¢) is a (complex) function of ¢ and 8(¥) is the Dirac delta function. Equation (20) describes a concentrated velocity distribution located at y=y,. The shape of the free surface resulting from such a distribution may be obtained, as a power series in g, by substituting (20) in equation (17). Such substitution yields ss 74) ae cos [(+1)8] (’ T (x) (t—2)2"dz | n+] 2 ioe) fAlx,t)=— - x re eas (x2+yo) 2 °° | ee. (21) Tn=0 (3)n-2°" 0 where §=tan-! é) , 176 A. H. LOW For an impulsive velocity at y=, we have T (Ho) Equation (21) then becomes 2 2) (—ef?\" "cos [(7-+-1)0 fci—- 2s — . SW)... ae (22) Tv n=0 eae (x2 -+-y6) 3 where p—tan("). Yo In this case we can obtain from equations (16) and (19) the form of the free surface for large values gt of ——=——— _, namely 4a/(x* +9) V ret ( —gyol? ) 30 Fe Gi x,t)~— 2, exp 2 — 2° _( sin ee ae 23 Fale) (x? $y2) 3/8 *P 1 42 Ly2) | e A(x? +2) | - where p—tan(=), An expression for the remainder may be determined from (19). Yo The well-known results of the classical Cauchy-Poisson problem obtained by Lamb ([5], [6]) are derived (apart from a factor 2 explained by our adoption of the convention that | d(a)da = 1] 0 by substituting y)»=0 in equations (22) and (23). These results for the series and asymptotic forms of the free surface are 9 ee) (—1)” et? 2m+1 (x,t)=—_— reel ES re es an 8 24 Pale) TX m=0 Ceate, ae and eee gt gt") JolX0) Rea ies) +sin ( ‘we oS (25) respectively. By virtue of equations (12), (13) and (14), we may also determine from (24) and (25) similar expressions for the free surface profile due to pressure distributions of the form (x,t) =8(0)8(x). These are 3 (=1)"(2m-+1) (gt)? )=— ee ened Doel (en arn 26 ae a ica F 7 and p gt? . {gt ~——,/_§ 2 Asin (2 |}, aca she eee A(x.) 3 ss COs ( i) sin ( alt (27) respectively. In fact, the series form of the shape of free surface due to a more general pressure distribution p=T(f)d(x) can be obtained by use of equation (13) by first substituting U(y,t)=T7(é)d(y) in (17). For such a pressure distribution it is found that, for x>0, Ail%t)= e 3 Shige) le et (¢-—7)** 1 Tisldts eee TOX* n=0 (3) om41 4% 0 The series involved in the results (24) and (26) may be evaluated using tables computed by Lommel [7]. “Fer b INITIAL VALUE PROBLEMS IN TWO-DIMENSIONAL WATER WAVE THEORY 177 (ii) If a thin wedge, of angle 2<, moving with constant speed uw along the y-axis plunges into the liquid at rest, then Ce ee | U(y,t) =eutl —H(y—u)}, where H(y—uwt) is the Heaviside step function. From (16) we find —pr? eu? ft di 3. ot fed — Sol agama: (Sze) a) tga (HS 0 : 3 From the series form of (155) we have s eu io) t (Salome fs 1 1 rs OG a a Er ° 2 m which agrees with an earlier result [8]. References [9] Low, A. H., 1968. J. Aust. Math. Soc., 8, 269-274. Trans. Roy. Sec. [10] Macxkig, A. G., 1963. J. Aust. Math. Soc., 3, [1] CLarKE, (Rev.) W. B., 1869. IN-S-W.,) 3,: 3. [2] CockLe, Hon. Chief Justice, 1867. Tvans. Roy. 340-350. Soc. N.S.W., 1, 27-30. [11] Macxiz, A. G., 1965. J. Aust. Math. Soc., 5, [3] ErpELy1, A. (Ed.), 1953. (a) Higher Trans- 427-433. cendental Functions, Vol. 1. (b) Higher [12] MiLEs, J. W., 1962. J. Fluid Mech., 13, 145-150. Transcendental Functions, Vol. 2. McGraw- [13] Prppuck, F. B., 1912. Proc. Roy. Soc., A, 86, Hill, New York. 396-405. [4] Erp#Lty1, A. (Ed.), 1954. Tables of Integral [14] StoKER, J. J.,1957. Water Waves. Interscience, New York. Transforms, Vol. 1. McGraw-Hill, New York. [5) Lams, H., 1932. Hydrodynamics. 6th edition. Cambridge University Press. [6] Lams, H., 1904. Proc. Lond. Math. Soc., 2, 371-400. [7] LommEL, E., 1886. Abh. d. k. Bayer Akad. d. Wiss., 2& Cl, XV. [8] Low, A. H., 1966. J. Proc. Roy. Soc. N.S.W., 100, 29-32. Frontiers in [15] WEHAUSEN, J. V., 1965. Research Interscience, Fluid Dynamics, Chapter 18. New York. [16] WEHAUSEN, J. V., AND LalITONE, E. V., 1960. Handbuck der Physik, Vol. IX, 446-778. Springer-Verlag, Berlin. 7 oD oy on , gw x be fore Niet i y = rk Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 179-182, 1968 Mesozoic Stratigraphy of the Narrabri-Couradda District J. A. DULHUNTY Department of Geology and Geophysics, University of Sydney ABSTRACT—The Mesozoic stratigraphical sequence previously established to the south and south-west, was followed north-east from Narrabri to Couradda, through a narrow zone of outcrop between Tertiary volcanics to the east and Cainozoic alluvium to the west. Upper Jurassic Pilliga Sandstone, and Purlawaugh sediments with mid-Jurassic (J4) microflora, were established overlying Triassic sandstones and conglomerates continuous with Napperby and Digby sediments in areas to the south. No Cretaceous sediments were recognised in outcrop, but they may occur concealed beneath alluvium immediately to the west. Evidence was found of the possible occurrence of Garrawilla lavas beneath Purlawaugh sediments near Couradda, suggesting Mesozoic volcanic activity contemperaneous with widespread eruptions some 50 miles away to the south-east. Introduction Results recorded in this paper are the out- come of an investigation of Mesozoic strati- graphy, in an area lying immediately to the north-east of Narrabri. This area, extending from Narrabri to the locality of Couradda, along the Terry Hie Hie road (see Figure 1), lies on the eastern margin of the Great Artesian Basin. It represents a narrow corridor of Mesozoic outcrop, in places only eight miles wide, limited to the east by great thicknesses of Tertiary alkaline volcanics of the Nandewar Mountains, and bounded to the west by Tertiary and Pleistocene alluvium of the North-Western Plains. The Mesozoic outcrops in this corridor are very poor, being largely obscured by local alluvium and low relief. However, they are the only surface outcrops available between the Boggabri-Gunnedah-Coonabarabran region to the south, and the Terry Hie Hie-Gravesend- Coolatai districts to the north. Mesozoic outcrop stratigraphy, along the north-eastern margin of the Great Artesian Basin in New South Wales, has been established over long distances from Dubbo to Coona- barabran, Gunnedah and Boggabri (Dulhunty, 1965, 1967a, and 1967) ; Kenny, 1963 ; Offen- berg, 1968a and 1968); Offenberg, Rose and Packham, 1968; Rasmus, Rose and Rose, 1967 ; Wallis, 1968). In Queensland, it has been established to the east and south-east of the Surat Basin, and followed towards north- eastern areas of New South Wales (Mack, 1963). The narrow corridor between the Nandewar Range and the North-Western Plains, from Couradda to Narrabri, provided the only opportunity of following Mesozoic outcrop geology from South-Eastern Queensland to Central-Western New South Wales. In view of this, the present investigation was undertaken. Results will, it is believed, assist broad regional correlations in regard to shoreline sedimentation along the eastern and south-eastern margins of the Great Artesian Basin, and aid future studies in stratigraphy and palaeogeography. Field investigations were confined to studies of Triassic and Jurassic sediments outcropping within the area of the accompanying geological map (Figure 1). Small areas of Permian sediments and volcanics were mapped in the south-eastern corner, but not studied in detail. Similarly, the western margin of well-known Tertiary alkaline volcanics of the Nandewar Mountain was mapped, but not studied, along the eastern side of the area. To the west, along the Narrabri-Moree road and railway, there occur vast areas of Tertiary to Recent alluvium of the Black Soil Plains, possibly overlapping, to the east, marginal Cretaceous sediments to lie on eroded surfaces of Jurassic sandstone. Concurrently with the present investigation, G. R. Wallis, of the Hydrology Division of the New South Wales Geological Survey, was engaged in regional mapping within the Narrabri district and adjoining areas, and the author had the advantage of discussion and collabora- tion. Mesozoic Stratigraphy South of Narrabri Previous work immediately to the south of Narrabri (Dulhunty, 1967b), established a Mesozoic sequence of basal Digby conglomerate underlying thin but variable thicknesses of Napperby sandstone; both being almost certainly equivalent to Narrabeen sediments of the Sydney Basin. South-west of Boggabri, Triassic beds are separated from overlying Jurassic Purlawaugh sediments by erosional residuals of Garrawilla lavas, but to the north, towards Narrabri, the lavas disappear and Purlawaugh sediments, lying directly upon Triassic, become thinner. Above the Purla- waugh sediments there occur considerable thicknesses of Jurassic Pilliga Sandstone, outcrops of which occupy areas of Pilliga Scrub west of Boggabri and south-west of Narrabri. 180 Mesozoic Stratigraphy of the Narrabri- Couradda District Triassic Sediments Conglomeritic Digby sediments and overlying Napperby sandstones both occur in the Narrabri- Couradda district. Good outcrops of full sections occur above Permian sediments in the south-eastern corner of the district. In the northern half of the district, north of Spring Creek, outcrops of Triassic rocks are almost entirely concealed by Nandewar Volcanics. To the south of Narrabri, near Boggabri, Napperby and Digby beds appear to thicken and thin, respectively, with increasing distance from their shorelines of deposition (Dulhunty, 19670). In the Narrabri-Couradda district, both sections of the Triassic are somewhat more constant in thickness, as far as can be ascertained from studies of full sections in the south-eastern portion of the district. The Digby con- glomerates, lying immediately above Permian sediments, vary from 50 to 75 feet in thickness, and Napperby Beds amount to about 300 feet. There is some evidence of a gradual increase in total thickness of Triassic sediments, from some 350 feet east of Narrabri to over 400 feet north of Spring Creek. The Digby Beds consist of heavy conglo- merates, generally similar in lithology to the thin outcrops between Boggabri and Gunnedah. The Napperby Beds are slightly less calcereous and flaggy, and contain more shaley layers, than in the south. They consist essentially of light-coloured shaley sandstones and_ gritty shales, interbedded with thick beds of white massive cliff-forming sandstones. Garrawilla Volcanics Garrawilla lavas, sills and tuffs, of late Triassic or early Jurassic age (Dulhunty and McDougall, 1966), do not occur between Narrabri and Boggabri, and the present investigation has not revealed any Garrawilla Volcanics in the southern half of the Narrabri-Couradda district. However, there is evidence of their possible reappearance in the northern half of the district, between the valley of Spring Creek and Couradda. On the southern side of Spring Creek valley, near the north-eastern corner of Killarney State Forest, and immediately to the east, there occur outcrops of deeply weathered basic igneous rock at the top of the Triassic and below Purlawaugh sediments, some 60 feet beneath the base of the Pilliga Sandstone. They may well be sills, but in mode of occurrence they clearly resemble outcrops of Garrawilla Vol- canics. At the same horizon, on the northern side of Spring Creek valley, weathered basaltic J. A. DULHUNTY igneous rocks outcrop along very gently sloping hillsides, east from the Narrabri-Couradda road, for about 1-5 miles until obscured by Tertiary Nandewar Volcanics. This occurrence also closely resembles the outcrop of Garrawilla lava, and is represented by a “ query outcrop” of Garrawilla Volcanics in the accompanying map, Figure 1. No further outcrops are available to the north as Mesozoic sediments dip north-west and the surface rises, but several bores put down through Pilliga Sandstone, between Spring Creek and Couradda, have penetrated fine- grained basaltic rocks at depths of 200 to 300 feet. Basalt cuttings were provided by D. S. Blair, from a depth of 220 feet in a bore put down through Pilliga Sandstone on his property “Glencairn’’, at the point marked Bore A in Figure 1. This material together with speci- mens from outcrops along the northern side of Spring Creek valley, were sectioned and examined by T. G. Vallance of the Department of Geology and Geophysics, University of Sydney, who had previously examined Garra- willa and Tertiary basalts from the Coona- barabran-Gunnedah region. Whilst it is not possible, as yet, to distinguish conclusively between the two by petrographic means, Vallance considers that the Couradda sub- surface basalts possess features in common with basalts of the Garrawilla Volcanics, to which they could well belong. The reappearance of Garrawilla Volcanics in the Mesozoic sequence north of Narrabri, if eventually established, would represent an independent extrusion of lavas in a separate area, but on the same horizon and contem- poraneously with the Coonabarabran-Gunnedah eruptions. Purlawaugh Sediments Purlawaugh sediments outcropping from beneath Pilliga Sandstone, south of the present area and west of Boggabri, attain a thickness of about 400 feet (Dulhunty, 19675), but become thinner to the north where they extend into the Narrabri-Couradda district. They are characterised by tuffaceous-like sediments, shales, mudstones and lithic sandstones. On weathering they produce highly ferruginous rich red-brown soils containing haematitic and limonitic concretionary nodules, frequently referred to as “‘ red-bed’”’ outcrops. The occur- rence of Purlawaugh sediments at the base of the Pilliga Sandstone, is marked by a sudden change in general lithology from overlying coarse quartz-sandstone producing red sandy soil, to underlying shale and lithic sandstone with ‘ red-bed ’’ outcrops. MESOZOIC STRATIGRAPHY OF NARRABRI AND COURADDA DISTRICT = 181 LEGEND Na yin ™® a > SG TERTIARY ~=—= m= at REGENT pile @ ‘ N seer SN one TERTIARY beater 7 {S; ne 4° [= | oO @ 1 JURASSIC Hire ttle | gt ew 2 i] @ e : Garrawilla Volcanics f o¢ ' 7 oO i . ° oO } TRIASSIC Napperby and Digby x ee Wt Sediments 3 oe I i = »? —_— PERMIAN Sediments & Volcanics = ce we ' | a ce Pet { --~N * os ne 1 \- Roads a See tay | a Ss Railways a o& 4 Oo oO oO ‘ 4 Miles > x = q ow J ~ 8 a - = Kilometres < = See "*Bobbiwaa SEX TERTIARY VOLCANICS PERMIAN * Killarney ‘SE - UF. y, PILLIGA PURLAWAUGH ALLUVIUM Fic. 1—Geological map of the Narrabri-Couradda District. 182 In addition to continuity of occurrence from areas to the south, and lithological characterisa- tion, Purlawaugh sediments were established in the Narrabri-Couradda district by palynological evidence. A specimen of shale, provided by B. A. Booker of the New South Wales Forestry Commission, was collected from immediately beneath the Pilliga Sandstone in a bore in Bobbiwaa State Forest (see Figure 1, Bore B) at a depth of between 210 and 240 feet. An examination by R. J. Helby, palynologist of the New South Wales Geological Survey, established in the specimen a J4 microflora of mid-Jurassic age (Evans, 1966), characteristic of upper Purlawaugh sediments to the south and south-west. Total thickness and detail lithology of the Purlawaugh sediments in the Narrabri-Couradda district, is very difficult to determine, owing to the extensive occurrence of alluvium which obscures outcrops over most of the area. Where surface outcrops occur, direct measure- ment of thickness is prevented by low relief in almost every instance. Data recorded during the sinking of water bores is of little help, aS specimens are necessary for palynological and lithological determinations. However, as a result of consideration of all evidence, the probable thickness of Purlawaugh sediments would appear to vary from some 150 feet near Narrabri to as little as 50 feet at Couradda. The general lithology appears to be very similar to that of Purlawaugh sediments in the Gunnedah-Narrabri-Mullaley region. Pilliga Sandstone From the north-eastern corner of the Pilliga Scrub, south of Narrabri, outcrops of Pilliga Sandstone swing easterly into the valley of the Namoi River, as a result of regional dips changing from approximately west-north-west to north-north-west. At this point the river turns west and Narrabri is situated on alluvium on the northern side of the valley. Pilliga Sandstone passes beneath the river, and out- crops in a low timbered rise lying immediately to the east of the Narrabri airfield (see Figure 1). To the north of Narrabri, the dip of Pilliga Sandstone swings back to approximately west- north-west, and outcrops occur to the north- north-east of Narrabri. They form slightly elevated and timbered rises, including the State Forests of Killarney, Bobbiwaa, Couradda and Moema. All are surrounded by alluvium, and their sandy surfaces and strata dip gently to the west-north-west passing slowly beneath the plains. MESOZOIC STRATIGRAPHY OF NARRABRI AND COURADDA DISTRICT The most northerly outcrop of Pilliga Sand- stone occurs at Couradda, on the northern side of Curramanga Creek. Beyond this point Tertiary basalt flows pass down from the Nandewar Range and out onto the plains, submerging all outcrops of older rocks for some miles along the Terry Hie Hie road towards Berrygil where widespread outcrops of Mesozoic strata again appear to the north of the Narrabri- Couradda “ corridor ”’. As far as can be ascertained, the general lithology of the Pilliga Sandstone, so charac- teristic of outcrops along the eastern and southern sides of the Pilliga Scrub, persist to the north of Narrabri. It is essentially a coarse ferruginous porous sandstone, with irregular developments of conglomerate, sporadic occurrences of pebbles, and occasional interbedded lenses of yellow limonitic and gritty grey-yellow clay shales. The maximum thickness of Pilliga Sandstone is difficult to determine but would appear to be about 250 feet with an eroded upper surface between Narrabri and Couradda, and possibly 400 feet along the western side of the area shown in Figure 1. References DuLuunty, J. A., 1965. The Mesozoic Age of the Garrawilla Lavas in the Coonabarabran-Gunnedah District. J. Proc. Roy. Soc. N.S.W., 98, 105. Dutuunty, J. A., and McDovuaatt, I., 1966. Potas- sium Argon Dating of Basalts in the Coona- barabran-Gunnedah District. Aust. J. Sci., 28, 393. DuLuHunTY, J. A., 1967a. Mesozoic Alkaline Volcanism and Garrawilla Lavas near Mullaley, New South Wales. J. Geol. Soc. Aust., 14, (1), 133. DuLuHunNTY, J. A., 19676. Mesozoic Geology of the Gunnedah-Narrabri_ District. J. Roy. Soe. N.SiW: Evans, P. P., 1966. Mesozoic Stratigraphic Palynology in Australia. Aust. Oil and Gas Journal, 12 (6), 58. Prince Publishing Group, Sydney. Kenny, E. J., 1963. Geological Survey of the Coona- barabran-Gunnedah District with Special Reference to the Occurrence of Sub-surface Water. Dept. Mines. N.S.W., Min. Res., No. 40. Mack, J. E., 1963. Reconnaissance Geology of the Surat Basin Queensland and New South Wales. Bur. Min. Res., Petroleum Search Subsidy Acts, Pub. No. 40. Dept. Nat. Development, Canberra. OFFENBERG, A. C., 1968a. Gilgandra 1: 250,000 Geological Series Sheet SH 55-16. Geol. Sur., Dept. Mines, N.S.W. Sydney. OFFENBERG, A. C., 19686. Tamworth 1 : 250,000 Geological Series Sheet SH 56-13. Geol. Sur., Dept. Mines, N.S.W. Sydney. OFFENBERG, A. C., Rose, D. M., and PacKHaw, G. H., 1968. Dubbo 1 : 250,000 Geological Series Sheet SI 55-4. Geol. Sur., Dept. Mines, N.S.W. Sydney. Rasmus, P. L., Rose, D. M., and Ross, G., 1967. Singleton 1: 250,000 Geological Series Sheet SI 56-1. Geol. Sur., Dept. Mines, N.S.W. Sydney. Wattis, G. R., 1968. Narrabri 1 : 250,000 Geological Series Sheet SH 55-12. Geol. Sur., Dept. Mines, N.S.W. Sydney. Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 183-196, 1968 Progressive and Retrogressive Metamorphism in the Tumbarumba- Geehi District, N.S.W. BRIAN B. Guy Depariment of Geology and Geophysics, University of Sydney, Sydney. N.S.W. 2006 ABSTRACT—Regional metamorphism of a group of pelites, psammopelites and psammites in the Tumbarumba-Geehi district has produced a sequence of metamorphic zones centred about foliated granitic rocks. It is considered that the mineral phases originated during four main pulses in the metamorphism. Two progressive metamorphic pulses are evident. These have produced a white mica—opaque oxide assemblage at low grade, whereas biotite, andalusite and cordierite are present at medium to higher grades. Mineral assemblages allow sub-division of the metasediments into four zones, namely, low-grade, biotite, knotted schist and high-grade zones. Two retrogressive metamorphic pulses are characterised by the development of chlorite, or of biotite closer to the metamorphic focus. The distinctive chemistry of the original sediments (high Al, high K : Na ratio) and the presence of graphite in such rocks are believed to have been significant factors in producing the style of metamorphism that is typical of large areas in south-east Australia. Introduction The area to be described is underlain by granitic bodies, and by a regionally metamor- phosed pelitic—psammitic sequence that forms part of a large belt of Ordovician rocks (Joplin, 1945 ; Hall, 1952) extending throughout north- east Victoria and southern New South Wales. Two of the granitic bodies are associated with the regional metamorphism. These masses, the Corryong and Geehi granites! are biotite-rich, occasionally cordierite-bearing, frequently gneis- sic, and contain numerous sedimentary relics. They resemble the Cooma gneiss (Browne, 1914), Albury gneiss (Joplin, 1947), and the Wantabadgery-Green Hills granites described by Vallance (19535). Other granitic masses (Khancoban, Mannus Creek and _ Dargals granites) within the area appear to have been emplaced after the period of regional meta- morphism. This paper is concerned primarily with aspects of the regional metamorphism. Information pertaining to the granitic masses is to be presented elsewhere. Nature of the Metasediments The metasedimentary sequence is similar to that of the Wantabadgery area, where Vallance (1953a) noted that the relative proportions of the major rocks are pelites (209%), psammo- pelites (60°%) and psammites (20%). In the Tumbarumba—Geehi district pelites may be 1 The term “ granite ’’ as used in this paper includes all acid plutonic rocks unless otherwise stated. somewhat more abundant, carbonaceous pelites in particular being common in the lower grade areas south of Tumbarumba, and south and west of Khancoban (Fig. 2). Adelong Canberra, ty “aGeehi Fic. 1 Locality map, Tumbarumba-Geehi district, N.S. W. 184 BRIAN Bi-GUY b| er el ey ee ea xxx xxx x yy ANE 17 ‘an 4a8 a EK HK CR ete ye ioe AKER Re Ke RAK Ke x xlKR x x exe Ke xX Ke uN y x x x x xuexw ye EK KA RIK te te xxx x xn y B x ee MK y xxx KK yY YX bed sh a aek Caer WO eas 3 tet aMs tet yen Wr iur Hry eau en PF Kh Kiet og! Pay iio ‘gic SEFC) @ “x x x acl POOR ’ Sei” e x $ote4 SEtSttt eet sssetts “Ne { | TANG Ae y pasate ‘ Wy | *. £F } x oa pee: ‘B ‘ ~ tees We Or. x x x uu x HK OA we OK Se Ke RR OW RE eee ee 160 16 ~ x Kx KX x euxnyx x xnwxxnenun yx Ru x x ea KK KR HM x 2e x ae xXx Rx KR x 1] | ¥ AAA TT HHH THT ; HT} | I | HHI || HATH + ee. vl ee ood e De se aGaaD na Ht a): Wao aen aes fi be pr aty siege h M eae an ele ak gs conte ea fee ee aie &iwi+ie + + Sar Vee Sa as aaa oe I d + + + At ata tata te Tel ates Cia sis tia POM AN ccbec enn e Ga oonees Hea Aan tea Gans Gated tenes | Hp reeeeC y.ru a croetn c Pe nD | peeaer") pe so Set ier i er th (Coes Meno ene eee | eau ct= Se ee 4] ||| Miiroeatan\ Rtg t at 5 Telli & proses es eeeesesy ll * ao bey Sacre ail HII x x +teH4 +7 +f'|lll]lill) ata tot Salil x x ATT sores tag oll x x Af nt + Db t+ tSBAIE ||) 4 - ral. ; x i +747 Sire an BS 7 bipece nae: , ies eee ir ee, aera hy 14; A tack geeecas \ ar SSS ts ++ + SSS Fic. 2 Geological map of the Tumbarumba-Geehi district, N.S.W., referred to the Snowy Mountains Authority grid. -LEGEND. METASEDIMENTS (ZONES) il HIGH GRADE ut KNOTTED SCHIST mM BIOTITE nM LOW GRADE HORNFELS GRANITES CORRY ONG Me & GEEHI KHANCOBAN ++- DARGALS MANNUS CREEK bell (undifferentiated) He BASALT ALLUVIUM ~ geological / boundary Vv fault He stream PROGRESSIVE AND RETROGRESSIVE METAMORPHISM The metasediments have a north to north- west trend, with local variations. Steep dips (>65°) are typical, and some of the folding is almost isoclinal. A steep regional cleavage—at times coincident with, but often at a low angle to bedding and transposing it—is developed in the pelites and psammopelites, as also is a prominent strain-slip cleavage. This latter cleavage deforms the slaty cleavage, and is especially evident in the medium- to higher- grade area. Numerous faults, some of which extend for many kilometres with considerable displacements, post-date the folding and meta- morphism. Chemical Features.—Although only limited data are available for the metasediments of the present area, some 40 analyses have been utilized in a study of the south-east Australian occurrences of similar type. Considerably more analyses are available for the pelites than for the sandier rocks, although such groups display A K F hie, 3 AKF diagram for pelitic rocks discussed in this paper A = Al,O, — (Na,O + K,O + CaO), K = K,O, F = MgO + MnO + FeO (mol.%). Fe,0O3, has been recalculated as FeO and included in F. Stippled area: South-east Australian pelites. Analy- tical data from Howitt (1884, 1886, 1888) ; Tattam (1929); Joplin (1942, 1945, 1947) ; Vallance (1953a) ; Guy (1964). Vertical hatching: ‘‘ Average’’ analyses of North American, pelites. Analytical data from Eckel (1904) ; Clarke (1924); Schmitt (1924); Nanz (1953) ; Shaw (1956). Diagonal hatching: Japanese metasediments. Analy- tical data from Miyashiro (1958); Oki (1961). Triangles: Pelitic rocks from the Scottish Highlands. Analytical data from Higazy (1952); Snelling (1957). 185 certain chemical similarities. The south-east Australian pelites have a number of distinctive properties (see Joplin 1962). For instance, the unweighted average of Al,O, is 23°%, although Pettijohn (1957) notes that the “ average ”’ shale contains (ca) 15°% alumina, with few shales containing more than 20°, Al,O,. CaO Na,O: K,O plot for pelites used to construct Fig. 3. @ South-east Australian pelites. X North American pelites. O Japanese metasediments. + Scottish Highlands pelites. is low (<1%%) while the K,O content and the K,O/Na,0 ratio are high (Fig. 3). K,O contents of the psammopelites are usually in excess of 3%, while CaO is less than 0:5°%. Chemical variation within the metasediments from south- east Australia is limited (see Fig. 3). Graphical representation of the chemistry of the metasediments is indicated in Figs. 3 and 4. In Fig. 3 a comparison had been drawn with pelites from other areas that have experienced regional metamorphism (viz. the Scottish High- lands and Japan) as well as from areas of North America. Distribution of the Metamorphic Zones Regional Zones Four main zones of regional metamorphism may be recognised and these correspond to the zones of the same name used by Vallance (1953a) for the area north of Tumbarumba, viz., low- grade zone (chlorite zone?), biotite zone, knotted schist zone (andalusite zone”), and high-grade zone (permeation and injection zones?). The low-grade zone is defined on the basis of apparent stable co-existence of chlorite and a white mica (muscovite or sericite), although Vallance (1953a, p. 99) reports a greenish biotite in parts of this 2 Terminology of Joplin (1942) for Cooma metamor- phics. 186 zone. The biotite isograd is determined by the first occurrence of a brown biotite, whereas the first development of andalusite or cordierite defines the position of the knotted schist isograd. The biotite and knotted schist zones attain 3 to 5 km. in surface width. The high- grade zone is limited to less than 500m. in width. This zone is defined on the basis of the stable co-existence of andalusite and potash feldspar, or on the development of sillimanite. Owing to marked retrogressive effects, as well as muscovitisation of rocks within this zone, recognition of critical mineral assemblages was found difficult. Other criteria, viz: (1) develop- ment of a second generation of (pink) andalusite and (2) presence of a Jit-far-lt structure or even a granular (rather than a schistose) texture, were found to be consistent with the above mentioned “ critical ’’ minerals. All the regional isogradal surfaces appear to dip steeply. The regional metamorphic zones are generally centred around or have the maximum grade developed adjacent to the Corryong and Geehi granites (Cooma-type granites). Exceptions occur south of Tumbarumba and north-east of Geehi (near G.R. 285-0—140-7)? where there are abrupt changes of grade. In such cases there is evidence of intense shearing in the granites and metamorphics with retrogression of mineral assemblages, particularly knotted schists. The Tumbarumba Creek, Geehi Walls and Bogong Creek faults are the major dis- locations to have disrupted the zonal sequence. North-east-trending thrusts occur in_ the Khancoban district (Cleary e¢ al., 1964) but such dislocations have not produced any anomalous features in the zonal sequence. A minor focus of metamorphic intensity occurs between the Swampy Plains and Murray Rivers (Indi Range), the knotted schists in this region are presumably related to high-grade rocks and possibly granite at depth. Contact Zones Adjacent to the Mannus Creek, Dargals and Khancoban granites, contact thermal aureoles are superimposed on the regional zonal sequence. Small granitic masses at Biggera, Victoria and at the Granite Knob have produced significant hornfels zones, some of which are limited by faults. The surface width of the contact zones varies from several hundred metres to over two kilometres. Shallow dipping (40-50°) granite contacts have been established near the wider zones, e.g. at G.R. 268-2—173°6. 3 Snowy Mountains Authority Grid reference. BRIAN, B.(GUY Petrography of the Regional Zones Low-— Grade Zones Typical mineral assemblages developed in this zone are : (a) white mica—chlorite—opaque oxides— quartz—albite, (6) white mica—opaque oxides—quartz, (c) white (chlorite). Most of the pelites are very fine grained (<100u), and are composed of a colourless white mica interspersed with a pale green or yellow chlorite, with distinct preferred orienta- tion of these phases. Chlorite is subordinate in quantity and frequently absent. Although a decidedly minor phase in the pelites, quartz is prominent in granoblastic psammites and psammopelites. The grainsize of the sandy rocks ranges from 0:01 mm. to 0:1 mm., with a broadly bimodal distribution of granual constituents. Opaque oxides are common, while graphite is important in some pelites. mica — graphite — quartz — K FIG: 5 AKF diagram showing possible mineral assemblages for low-grade zone rocks from south-east Australia. Composition field for pelites is indicated. Within the low-grade zone, chlorite-rich rocks are not as abundant as, for example, at Cooma, N.S.W. (Joplin, 1942; Vallance, 1953a, p. 99). Much of the magnesium of the pelites and psammopelites is possibly located in the white micas (?phengites) and opaque oxides. Schaller (1950, p. 408) and Foster (1860) have suggested that such micas have a high Si: Al ratio. This would be consistent with the paucity of quartz in low-grade pelites as compared with higher- grade rocks. | | _may be present. q | i ] PROGRESSIVE AND RETROGRESSIVE METAMORPHISM TABLE 1 Colour and Refractive Index Variation in Biotites of the Biotite Zone with Percentages of various Types Low Prominent Colour of Z (a) Pelites : Yellow-greenish yellow .. 100% Olive to mid-brown 0% Red brown 0% (6) Psammopelites Yellow-greenish yellow .. 50% Olive to mid-brown 50% Red brown 0% In Fig. 5 possible mineral associations are noted for the south-east Australian meta- sediments. The majority of rocks lie in the field of a white mica—iron oxide association. It may be noted that the compositions of pelitic rocks from other terrains, as illustrated in Fig. 3, are slightly removed from the present pelites and such rocks would fall into fields 2 and 3 (Fig. 5) where more chlorite may be expected (cf. Barrow, 1912; Tilley, 1925; Oki, 1961). Biotite Zone The following mineral assemblages have been observed within this zone : (a) biotite — muscovite — chlorite — (opaques)—(quartz). (5) biotite—muscovite—quartz. (c) biotite —-muscovite — opaques — quartz albite—(potash feldspar). (d) (biotite)—muscovite—-graphite—quartz. There is strong preferred growth of micas (in the slaty cleavage) in this zone and some tendency for biotite to form knot-like clots up to 0:25 mm. across in higher grade sections. However, this latter feature rarely interferes with the mapping of the knotted schist isograd (cf. Tattam, 1929, p. 10). The micas are the most prominent minerals in the pelites, with biotite dominant. The variation in pleochroic scheme and y for the bioties are listed in Table 1. Red-brown biotites have not been observed in the pelites (cf. psammites) in the Tumbarumba—Geehi district although Vallance (1953a) notes that the typical biotite in the upper part of the biotite zone in the area north of Tumbarumba has Z = dark red-brown. The associated white mica is probably muscovite (with 2V, = 33--42°) but phengitic varieties Except for the lower grade E Biotite Zone Mid Biotite Zone High Y Biotite Zone 60% 35% 1-649 40%, 65%, 1-636 0% 0% Se 50% 40%, 1-649 50%, 4.0%, 1-638 0% 20% 1-640 parts of the zone, chlorite is limited and most blades are associated with retrogressive effects. In some rocks carbonaceous material is occa- sionally in excess of 60°% of the rock, with dark olive-brown biotite as an associated phase. In some pelitic and psammopelitic rocks subhedral flakes of chlorite are developed oblique to the plane of the schistosity. This mineral, which is only significant in higher- grade sections of the zone, has apparently crystallized after the other constituents of the rock. A discussion of the relation of these chlorites to the regional metamorphism is deferred to p. 190. K Fic. 6 AKF diagram showing possible mineral assemblages for biotite zone rocks from south-east Australia. Composition field for pelites is indicated. Many authors (Harker, 1939; Ramberg, 1952 and Yoder, 1959) suggest that a reaction between chlorite and white mica at the biotite isograd produces biotite. It is possible that Opaque oxides observed in the Tumbarumba- 188 BRIAN B. GUY TABLE 2 Colour and Refractive Index Variation in Biotites of the Knotted-Schist Zone with Percentages of various Types Low Knotted Schist Zone Prominent Colour of Z (a) Pelites Yellowish brown 60% Olive to mid-brown 30% Red brown 10% (6b) Psammopelites and Psammites Yellowish brown 50% Olive to mid-brown 10% Red brown 40% Geehi are magnesioferrites, so that the reaction at the biotite isograd may have been : phengite + magnesioferrite —> biotite + muscovite + quartz + magnetite Biotite zone assemblages in the Ordovician metasediments of south-east Australia are indicated on Fig. 6. Compositional variation of the white micas has been extended to include ‘“sericitic’’ varieties. Such micas_ possibly differ chemically from those of the low-grade zone. Knotted Schist Zone Assemblages developed are : (a) biotite—muscovite—quartz—andalusite. (b) biotite—muscovite—quartz—cordierite— Opaques. (c) biotite — muscovite — cordierite (?)— andalusite (?)—opaques—(quartz). (d@) quartz — biotite — muscovite — opaque —(K-feldspar)—(plagioclase). (e) quartz — muscovite — biotite — graphite —(cordierite)—(andalusite). Assemblages (a) to (d) have been plotted on an AKF diagram in Fig. 7. The pelites are distinctly schistose, with a disruption of the foliation by knots of andalusite and cordierite. These minerals increase in amount with metamorphic grade while micas decrease from 70% to 30%. Quartz forms lenticular patches that are elongated in the direction of the slaty cleavage in the pelites, with porphyroblasts of andalusite and cordierite dividing such lenses into two sections (Fig. 8). Albite is present in the psammites although in higher grade sections of the zone a calcic plagioclase (Ango)* occurs. 4 Compositions of the plagioclases were determined from the extinction angle X’, (010) _| [100] measured on a universal stage and referred to the low-temperature determination curves of Bordet (1963). Mid Knotted High Knotted ¥ Schist Zone Schist Zone 35% 10% 1-644 25%, 20%, 1-645 40%, 70% 1-639 30% 10% 1-644 20%, 10% 1-636 50% 80% 1-642 Variations in physical properties of biotites are listed in Table 2, a significant decrease in abundance of yellow-brown types being evident in higher parts of the zone, while the red-brown biotites become prominent. Haematite is often associated with the yellow-brown varieties of biotite. Some chemical data for biotites from this metamorphic belt are available (Guy, 1964). A Andalusite Biotite K F BiG. 7 AKF diagram showing possible mineral assemblages for knotted-schist zone rocks from south-east Australia. After Turner and Verhoogen (1960), for hornblende hornfels facies. Composition field for pelites is indicated. The Mg:(Mg+ Fe) ratio is 0-50 for biotites and 0-35 for cordierites (see pp. 188-189). A mid-brown biotite from knotted schist zone in the present area has the formula: (Ko. goNaq-97Caq-91) _ (Mgo- ogFe*y. op Fe**5-29Alp- 37 Ng-17 119-29) (Sle. g9AAly- 31) Oro (OH)o while from rocks of equivalent grade Vallance (1960) records a red-brown biotite with the formula : (KK. 72Nay. pola. o2) _ (Mgo. oF e?*y-93Fe?*p-ogAlo- a1 Mng: og lig. 15) (Sta 75A1,- 25) O19 (OH)e. PROGRESSIVE AND RETROGRESSIVE METAMORPHISM Retrogressive alteration of biotite to chlorite is common in the sandier rocks. Muscovite, in large blades (0-4 mm.) with 2Vy = 37-40°, occasionally develops somewhat obliquely to the schistosity. Knots of andalusite and cordierite are subhedral to anhedral in shape, but in many cases it appears that growth has proceeded during deformation, as oval shapes are common and signs of rotation are evident, small trails of inclusions displaying a sigmodial arrangement. 189 considers that arcuate shapes for trails of inclusions is not indicative of rotation during growth, but is the result of flattening (cf. Spry, 1963). Most of the knots are rather altered, and only a limited number of fresh andalusites or cordierites have been observed. Cordierite (with sector twinning and 2Va > 65°) is the more abundant of the two minerals. The cordierite is weakly zoned with an iron-rich core. Using Miyashiro’s (1957) distortion index / and the Fic. 8 Two closely associated cordierite grains (stippled) in pelite from knotted-schist zone. Note the presence of granular quartz (clear) within the knotted area. There is a definite tendency for knots in the lower grade sections of the zone to occur in small clusters, as though the knots were either ruptured by deformation during growth or deformation has been such as to affect the nucleation of the knots producing two grains growing in juxtaposition (Fig. 8). Vallance (1953a, p. 108) suggested that there has been rotation of the knots into the plane of the schistosity (regional cleavage), but in many rocks of the Tumbarumba-Geehi district the porphyroblasts are aligned in the strain-slip cleavage, suggesting a rotation into the plane of this latter cleavage. Growth of the porphy- roblasts probably continued during the forma- tion of the strain-slip cleavage although knots may also have formed prior to the period of influence of this cleavage. Ramsay (1962) refractive index 8, two unaltered cordierites were found to have 1. (21639)5: A =0-19; B=1-548; approxi- mately 30°% Fe (for Mg.). 2 (ZAMRD eae A OT mately 42° Fe. There is rather extensive pseudomorphous replacement of the knots by large blades of chlorite and white micas. Some chlorite is yellow and nearly isotropic, although most chlorite has X=Y=mid to dark green, and Z=very pale green, with anomalous inter- ference colours and numerous pleochroic haloes. These bladed chlorite pseudomorphs frequently B=1-553 ; approxi- 5 University of Sydney, of Geology and Geophysics specimen number. Dept. 190 BRIAN display mimetic growth after cordierite within the rotated porphyroblasts. Crystallisation in such cases appears to postdate the rotation and hence the strain-slip cleavage. Some chlorite, however, appears to have been deformed by this cleavage and may have developed synchronously with it. In higher grade parts of the zone there is extensive interlaying of chlorite and white mica in the pseudomorphs. As noted above for the biotite zone rocks, chlorite porphyroblasts that are oblique to both the slaty and strain-slip cleavages are developed throughout the knotted schist zone. These presumably postdate forma- tion of minerals previously discussed. They are more common in the higher sections of this zone and attain several millimeters in length, being subhedral to euhedral and somewhat poikilitic, with a small central parting (twin- ning ?) parallel to their length. The chlorite is a mid-green variety with low birefringence and anomalous blue interference colours. The distribution of the porphyroblasts is not related to the contact thermal metamorphism, their development is apparently a phase of the regional metamorphism. In knotted schists adjacent to the Corryong granite, muscovite constitutes 50-55% of the rock, as large (2.0mm.) randomly oriented blades that obliterate the schistosity. Apatite is a common accessory in such rocks. The reactions leading to the formation of andalusite and cordierite appear to involve silica on the lower grade side (cf. Miyashiro, 1958, p. 243). This is suggested by the petro- graphic evidence of knots commonly existing in quartz-rich lenses and by the tendency of knots to occur in psammopelites at an earlier stage of the progressive metamorphism than in the pelites. High-grade Zones Assemblages developed include : 1. quartz — biotite — muscovite — plagio- clase (Ango). 2. quartz — biotite — muscovite — anda- lusite—(K-feldspar). 3. quartz — biotite — muscovite — andalusite —cordierite—plagioclase—opaques. 4. quartz — biotite — muscovite — anda- lusite—sillimanite—opaques. These have been plotted on an AKF diagram stro lees 8 All of the above assemblages display retro- gressive affects, such as the presence of chlorite or biotite pseudomorphing knots, and biotite B. GUY cutting across the regional foliation. Musco- vitisation of many rocks within the high-grade zone has obscured textural features, making it difficult to establish stability relationships between the various phases. The texture of many rocks in the high-grade zone is granoblastic although many of the pelitic rocks are still somewhat schistose. The grainsize 1s larger than in the knotted schist zone rocks. Quartz grains average 1mm. in the psammites and 0:2mm. in the pelites, while knots (now mainly pseudomorphed) attain A Sr = Feldspar = Fic. 9 AKF diagram showing possible mineral assemblages for high-grade zone rocks from south-east Australia. Broken lines after Turner and Verhoogen (1960) for almandine-amphibolite facies. Composition field for pelites is indicated. The high potash content of the metasediments and the decrease of Mg/(Mg + Fe) of of the biotites with increase in grade favour formation of cordierite rather than almandine. 0-8-1-0 mm. in size. Undulose extinction in quartz grains is more evident than in the lower grade rocks while in some examples banding or even cell structure (Wilms and Wood, 1949) is discernible (e.g., 21713). Small amounts of an optically homogeneous alkali feldspar are distributed through the psammopelites and the andalusite-bearing pelites. [ine string perthites are occasionally present, with a tendency for polysynthetic twinning to develop adjacent to the exsolved sodic lamellae. The plagioclase present in this zone is Ange 3, with ZV “(caso Biotites typically have X =pale yellow, Y = Z=dark red-brown (y ranging from 1-640 to 1-645) although in some cases (<10°%), dark olive-brown to dark mid-brown varieties (y = 1-640) exist. The absorption colours of these micas are much deeper than those observed for the previous zones. Pleochroic haloes PROGRESSIVE AND RETROGRESSIVE METAMORPHISM around zircon, apatite and (?) monazite are more common than at lower grades. A red- brown biotite from the present area has a formula of : (Ko. ggNag-ogCao-o2) _(M8o- g3fe? 41. 2Fe?* 9-21 Alo- 3g Mn. 91 Tig- 19) (Stg-6s8Ah1- 32) Oro (OH) 2, while Vallance (1960) records a_ red-brown biotite from the Wantabadgery area with the formula : (Ko. 74Nap. ogg. o2) _ (Mgo- poke? +). Fe? * 9.2: Alp: 36 Mn. 911 ip- 99) (Stg- 624hs- 48) Oro (OH)2. Opaque oxides are associated with biotite, and large blades of muscovite with 2Va = 38-44° are interlayered with biotite. Muscovite is present in several varieties in the high-grade zone, viz., (i) a fine variety pseudomorphing “knots ’”’, (i) large blades developed parallel to the regional foliation and (iii) coarse blades (2-3 mm. long) often in random orientation. Types (ii) and (ii) are not always readily distinguishable from each other. This mineral becomes locally abundant adjacent to the Corryong granite margins and it is possible that there may have been local introduction of potash in these areas. Most of the knots are altered to white mica and chlorite blades, with little or no evidence of any rotation. Owing to extensive replace- ment they are not as clearly distinguishable from the mica base as are the knots of the knotted schist zone. Inclusions of quartz and brown biotite are present within the knots. Small amounts of sillimanite have been observed in this zone, frequently as fine fibrous mats localised in quartz or quartz-rich areas. Some sillimanite appears to have formed from the breakdown of muscovite, but fine needles arranged at 60° to one another are not uncommon within biotite (cf. Chinner, 1961, p. 318). Cordierite is present in small, poly- synthetically twinned grains that display little or no alteration. A yellow, nearly isotropic chlorite may be associated with this cordierite. Possibly this cordierite is of a generation different from that which existed in the pseudomorphed knots. Unaltered ragged grains of pink anda- lusite occur as cores to some knots, and also in quartz-rich areas immediately adjacent to the knots. The pink andalusite is quite different both in occurrence and appearance from that observed in the knotted schist zone. Vallance 1953a, pp. 111-112) and Joplin (1942, p. 117) have described a similar situation for this mineral in rocks of equivalent grade. Textural relationships suggest that the pink andalusite 191 developed during the time of generation of the strain-slip cleavage. Some high-grade zone rocks, especially those near the Geehi granite, contain small irregular (up to 1-0 mm.) patches of mica aggregates and chlorite minerals that presumably represent pseudomorphs after cordierite or andalusite (e.g. 21623). These patches are similar to inclusions observed in the Cooma-type granites. The replacement of the knots by green chlorite may be of a slightly later origin than the develop- ment of brown biotite inclusions (see p. 191) within the knots. X-ray examination of chlorite pseudomorphs reveals in some examples an interlayering of muscovite with chlorite. Using powder diffraction techniques, the dy), and the “b”’ parameter (Brindley, in Brown 1961) were determined on three chlorite samples indicating compositions of : (1) (Spec. 21622). Mg, Fe Al (Si, Al) Oy (OH), (Z)mlopec, 2 IS)> Me, HesJAli(si, All ©., (OH)s, (3) (spec. 21719), Mg,., Fe, Al..2 (Sin, Alj-5) O19 (OH)s. (1) and (2) were partly interlayered with muscovite while (3) showed an association with muscovite but no apparent interlayering. The high Fe value for (3) was supported by relatively intense reflections of even 00/ spacings. Chlorite is dominant over muscovite in these samples. As in the knotted schist zone, euhedral chlorite porphyroblasts are developed obliquely to the regional cleavage. Such occurrences of this mineral within the high-grade zone are not as common as in the higher grade parts of the knotted schist zone—perhaps because of extensive muscovitisation in the high grade zone. Where present, this chlorite is usually green with a birefringence of 0-015. Euhedral brown biotite porphyroblasts cross-cutting the foliation have also been observed in sections of the high-grade zone, and its restriction to this zone suggests that the chlorite and _ biotite porphyroblasts are centred around the same metamorphic focus as the main regional influences. Abundant muscovite and occasional brown tourmaline in higher grade sections of this zone suggest local metasomatism of potash and boron (cf. Vallance 1953a, p. 117). Principally because of retrogressive effects, very little critical petrographic evidence is available for the mineralogical reactions that have occurred at the high-grade isograd. It 192 appears as if there has been initial development of andalusite and cordierite at a knotted-schist grade of metamorphism and the _pseudo- morphism of these knots by white micas, the potassium for the development of the micas may have been from some external source. The second (pink) andalusite may have been produced by a general breakdown of muscovite with further increase in grade. The limited occurrence of sillimanite in the present area may be related to late muscovitisation obscuring the presence of this mineral, as sillimanite is significant in adjacent parts of the metamorphic belt. Petrology of the Contact Zones Rocks discussed in this section are of a polymetamorphic origin ; thermal effects having been superimposed on regional metamorphic assemblages. Mineral assemblages include : (1) biotite—cordierite—quartz. (2) biotite — muscovite — cordierite — quartz— (opaques)—plagioclase (An,jy— Anjs). (3) biotite — muscovite — andalusite — quartz. (4) biotite — muscovite — quartz — garnet—- plagioclase (An,;). Assemblage (4) has been located at only one locality (G. R. 283.6-142.8). The first signs of thermal metamorphism of the pelites is the incipient development of spots, now composed of white micas, and stained heavily by iron oxides (haematite and limonite). These spots may be mica clusters or represent the commencement of development of andalusite or cordierite (with subsequent pseudomorphism). It is difficult to distinghish these spotted® rocks from weakly knotted regional metamorphic rocks. With increase in grade of contact meta- morphism, cordierite and andalusite become more distinct although generally they are retrogressed. Pseudomorphs after andalusite are often recognised by euhedral outlines with (110) and (011) common. Cordierite may be present as unaltered crystals with simple e“The™ term” spotted "1s “used ime thism paperuto qualify thermally metamorphosed rocks in which there has been little or no structural control evident in crystallisation of phases such as cordierite or andalusite. The term “‘ knotted ’’ is applied to regional meta- morphics where growth of the above mentioned phases has been strongly controlled by the stress field. BRIAN B. GUY twinning on (110) (see Venketesh, 1954), and also with sector twinning, frequently of complex appearance. Some cordierites displaying such twinning were examined from near _ the western margin of the Khancoban granite. They have a rather low distortion index (A)— 0 -10—the subdistortional cordierite of Miyashiro (1957), or intermediate state cordierite of Schreyer and Schairer (1961). The low A value may reflect the rapid crystallisation that would be expected in contact metamorphism. Most biotites are deep red-brown varieties with y = 1.638 — 1-646, although a few medium brown types have been noted. The garnet noted in assemblage (4) above, constitutes nearly 79% of the rock (21678) in which it is found, and occurs in relatively large crystals up to 0-5mm. Slightly pink in appearance, the subhedral garnet has a refractive index of 1-818—probably predominantly of the pyralspite series. Some of the chlorite porphyroblasts that post-date the slaty and strain-slip cleavages (pp. 190 and 191) and have developed during the regional metamorphism have been observed in the hornfelsed rocks. In such cases the chlorite is replaced by small crystals of red-brown biotite, displaying a preferred orientation, with the z-axis of the biotite perpendicular to the z-axis of the original chlorite. This confirms that the original chlorite porphyroblasts are unrelated to the contact metamorphism. Summary of Regional Metamorphic History From the foregoing discussion the variation envisaged between grade of metamorphism, time and space has been schematically displayed in Fig. 10. Conditions postulated for the high-grade, knotted schist, biotite and low- grade zones have been indicated by curves (1) to (4) respectively in Fig. 10, whereas the main thermal impulses have been represented by peaks A, B, C.D, FE on. these curves... am considered that each metamorphic zone has successively passed through conditions similar to that postulated for zones of a lower grade, but it is important to note that since tectonic conditions varied with time no zone would have a history identical with that of a lower zone over their common P-T range. The following sequence of events is postulated for the rocks in the regional metamorphic sequence. (2) A rise in the isogeothermal surfaces in the Earth’s crust causing recrystallisation, and PROGRESSIVE AND RETROGRESSIVE METAMORPHISM producing low-grade or biotite zone conditions throughout the area, deformation associated with regional (slaty) cleavage being important in controlling mineral growth at this stage. (6) Continued crystallisation of micas together with the appearance of cordierite and anda- lusite as stable phases. The growth of these minerals under the influence of deformation associated with slaty cleavage may have been fully realised only in the rocks now designated as high grade. At this stage the present knotted schist zone rocks may not have developed andalusite or cordierite (see Fig. 10, (1) A and (2) A-B). 4 pecrrrZZTIZZ Grade a high, a Aa a knottedl schist | biotite: low Time 193 have been important here in controlling or nucleating growth of the pink andalusite. At this stage (or slightly post-dating this, owing to time involved in heat transfer) the knotted schist zone rocks were developing cordierite and andalusite as well as a strain-slip cleavage. This cleavage is not evident in all sections of the knotted schist zone and at times post-dates the development of cordierite and andalusite as well as mica crystallisation in the biotite zone (see Fig. 10, (1) B, (2) A-B, (8) A-B, (4) A-B). (ec) A decreased in grade and/or change in chemical environment or sustained lower tem- LLL CCCI Fic. 10 Schematic diagram for south-east Australian metamorphics showing the relationship between ‘ ‘grade of metamorphism ’’, “‘ time ”’ (relative to the earliest pulses of metamorphism) and “‘ space ’”’ (i.e. distance from the regional metamorphic centre). schist, biotite and low-grade zones respectively. A, B, C, D represent Curves 1—4 refer to the metamorphic history of the high-grade, knotted 6é pulses ’’ in the regional meta- morphism and E represents contact influences of Cooma-type granites during emplacement. See p. 192 for a discussion of this diagram. (c) Perhaps a decrease in temperature and/or a slight change in chemical environment such that white micas are produced pseudomorphing knots, this change being evident mainly in the high-grade zone. (2) Increase in metamorphic grade with the formation of sillimanite, pink andalusite and some potash feldspar as well as recrystallisation of micas with biotite forming partly in “‘ knotted areas ’’ from by-products of retrogression of knots (see (c)). The strain-slip cleavage may perature conditions such that some general retrogression to chlorite and white micas occurred in phases such as cordierite and anda- lusite, and rarely biotites. This situation may have involved only a variation in PH20. In some sections of the area, deformation associated with the strain-slip cleavage may have been of significance and controlled growth of chlorite and white mica (see Fig. 10, (1) C, (3) C-D). (f) A shght increase in grade with the development of subhedral chlorite and very 194 occasionally brown biotite porphyroblasts oblique to the cleavages. Most of the influences of the stress field had waned by this stage. Steps (e) and (f) are clearly definable in the high grade and upper sections of the knotted schist zone, however, in the lower portions of the latter zone these steps are indistinguishable, and in the biotite zone not of significance (Seenbie: 10) (1) Ds .(2). 1) H(3)-C-B), (zg) Muscovitisation and, occasionally, tour- malinization of metasediments occurred in the high-grade zone and rarely in the knotted- schist zone. As these processes were effective only adjacent to the margins of the Cooma-type granites, it is likely that potash and boron introduction occurred with, and perhaps pre- ceded emplacement of, the Cooma-type granites (seesrie 10 9a) cand 4(2) Several important considerations arise from the foregoing summary. The major peak of metamorphism is divisible into two main pulses A and B (lig. 10) in the high-grade zone, and the minor peak is also divisible into two main pulses C and D (Fig. 10), whereas in the lower grade zones these pulses are not clearly definable. Pulse C is not as evident in the high grade zone as in the upper knotted schist zone, owing to the steep thermal gradients in the former zone. The thermal peak in curve (1), Fig. 10, occurred at the same time that the strain-shp cleavage was effective, while this cleavage was coincident and slghtly later than the thermal peak in curve (2). As the strain-slip cleavage post-dates the develop- ment of minerals in (3), it is possible that this cleavage may be of importance at different times throughout the metasedimentary sequence. A slight time lag may have existed in the thermal pulses between (1) and (4) due to the rate of heat transfer. Comparison of Metamorphic Styles Throughout the belts of metamorphic rocks in south-east Australia, there is a definite sequence of mineralogical changes with increase in grade of metamorphism. This style of metamorphism may be referred to as_ the “Cooma type” (Vallance, 1967) since it was first described from -N.S.W. in that region (Joplin, 1942). The metamorphism is regional in extent and characterised by the presence of andalusite and cordierite. It is similar to the Central Abukuma type (Miyashiro, 1958) and not unlike the Buchan type (Read, 1952), although the latter may have almandine, staurolite and even kyanite developed. These BRIAN B. GUY various styles of metamorphism (see Miyashiro, 1961) probably reflect differing sets of physical conditions. There are probably significant physical differences between the Cooma and Central Abukuma styles (see Vallance, 1967). Winkler (1965) reports that the Japanese metamorphics have biotite developed as one of the first minerals in response to metamorphism. This is certainly not the case for the south- east Australian rocks, but it is suspected that the lower sections of the greenschist facies are not exposed in the central Abukuma and Ryoke belts (cf. Oki, 1961). One of the major differences between south-east Australian and the Japanese sequences is the development of almandine garnet in the Central Abukuma metamorphics (although the mineral is rare in the Ryoke belt). Mineralogical data on biotites from the Khancoban region (Guy, 1964) indicate a decrease in Mg,: Mg, + Fe with increase in grade of metamorphism. This partitioning of elements may have favoured formation of cordierite rather than an almandine garnet. The higher potash contents of the Australian rocks would have influenced greater development of biotite, with a consequent decrease in available Fe relative to Mg. and thus further limiting the formation of almandine. Comparison between such sequences is partly complicated by oxidation-reduction conditions in the metasediments. Recently, Chinner (1960) and Miyashiro (1964) amongst others have emphasised the importance of graphite in this regard. Miyashiro suggests that Po, is essen- tially independent of dissociation of water and in graphite-rich rocks the Po, may be sufficiently great to effect diffusion of hydrogen into surrounding graphite-free rocks, especially at higher temperatures (i.e. higher grades of metamorphism). However, Chatterjee (1966) has noted that the buffering reactions of both oxygen and hydrogen should be considered in this problem in view of the work of French and Eugster (1965), who indicated that methane may be a significant component in such circum- stances under geologically reasonable conditions. The presence of graphite may thus be partly responsible for variations within and between metamorphic sequences, a possible example occurring in the present metamorphic belt being studied. Vallance (1953a) describes red- brown biotite as a common phase in biotite-zone rocks at Wantabadgery, whereas in the Tum- barumba-Geehi area such biotites are not common until high in the knotted schist zone. Vallance also notes the paucity of graphite- bearing rocks whereas these are common in the PROGRESSIVE AND RETROGRESSIVE METAMORPHISM area described here. There is no evidence from analytical data to suggest that the mobility of oxygen has been a significant process in influencing mineralogical development during metamorphism in south-east Australia. Recal- culation of chemical analyses into the form of cationic percentage (Guy, 1964) indicates no systematic variation in associated oxygens in the lower-medium grades of metamorphism. Thus the oxidation conditions appear to be a direct consequence of the availability of graphite. The retrogression of assemblages in the present area has limited the data available on the chemistry of most phases. Although the biotites do not appear so susceptible to retrogression, they may not prove very critical for study at moderate grades, because of apparent influence of graphite on their composition. As many mineralogical reactions are a function of Po, (Miyashiro, 1964) particularly those involving elements which may readily exist in more than one oxidation state, the partitioning of elements between various phases (e.g. biotite, cordierite, garnet) may well be related to the presence of graphite. Some authors (e.g. Winkler, 1965), consider that the style of metamorphism described here is intermediate between contact thermal and regional (Barrovian) metamorphism. The areal extent of the zonal sequence, and the style of deformation within the belt indicates that the metamorphism may indeed be described as “regional”’, the assemblages having been developed under conditions of non-hydrostatic pressure. Acknowledgements I wish to thank Associate Professor T. G. Vallance for advice and criticism both during this study and in the preparation of the manu- script. I am also indebted to Mr. D. G. 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Dept. Mines. N.S.W. HarKER, A., 1939. Metamorphism Methuen, London. Hicazy, R. A., 1952. A geochemical study of the Regional Metamorphic Zones of the Scottish High- lands. Int. Geol. Congr., 19, 15, pp. 415-430. Howitt, A. W., 1884. The rocks of Noyang. Trans. Proc. R. Soc. Vict., 20, pp. 18-77. Howitt, A. W., 1886. Sedimentary, igneous and Metamorphic rocks at Ensay. Tyvans. Proc. R. Soc. Vict., 22, pp. 64-124. Howitt, A. W., 1888. Notes on certain Metamorphic and Plutonic Rocks at Omeo. Pyvoc. R. Soc. Vict., 24, pp. 100-131. Jopiin, G. A., 1942. Petrological studies in the Ordovician of N.S.W. I. The Cooma complex. Proc. Linn. Soc. N.S.W., 67, pp. 156-196. Jopuin, G. A., 1945. Idem. III. The composition and origin of the Upper Ordovician graptolite-bearing slates. Proc. Linn. Soc. N.S.W., 70, pp. 158-172. JopLin, G. A. 1947. Idem. IV. The northern, exten- sion of the north-east Victoria metamorphic complex. Proc. Linn. Soc. N.S.W., 82, pp. 87-124. Jopiin, G. A., 1962. An apparent magmatic cycle in the Tasman Geosyncline. J. Geol. Soc. Aust., 9, pp. 51-69. MiyasHiro, A., 1957. Cordierite-indialite relations. Am. J. Sci., 255, pp. 43-62. MiyasHIRoO, A., 1958. Regional metamorphism of the Gosaisyo-Takunuki district in the Central Abukuma plateau. J. Fac. Sci. Tokyo Univ., 11, pp. 219-272, MiyasHiro, A., 1961. Evolution of metamorphic belts. J. Petrology, 2, pp. 277-311. MiyasuHiro, A., 1964. Oxidation and reduction in the Earth’s crust with special reference to the role of eae Geochim. cosmochim. Acta, 28, pp. 717- 729. Nanz, R. H., 1953. Chemical compositions of pre- Cambrian slates with notes of the geochemical evolution of lutites. J. Geol. 61, pp. 51-64. Unpublished Ph.D. thesis. Uni- (2nd Ed.). 196 Ox1, Y., 1961. Metamorphism in the northern Kiso Range, Nagano Prefecture, Japan. Jap. J. Geol. Geogr., 32, pp. 479-496. PETTIJOHN, F. J., 1957. Sedimentary Rocks (2nd Ed.). Harper, New York. RAMBERG, H., 1952. The Origin of Metamorphic Rocks. University Press, Chicago. Ramsay, J. G., 1962. The geometry and mechanics of formation of ‘“‘similar’’ type folds. J. Geol., 70, 309-327. READ, H. H., 1952. in the Ythan Valley, Aberdeenshire. Geol. Soc., 40, pp. 265-279. SCHALLER, W. T., 1950. An interpretation of the Composition of MHigh-silica Sericites. Mineralog. Mag., 29, pp. 407-415. ScumitTT, H. A., 1924. Possible potash production from Minnesota Shale. Econ. Geol., 19, 72-83. SCHREYER, W. and SCHAIRER, J. F., 1961. Composi- tions and structural states of anhydrous Mg- Cordierites: A re-investigation of the central part of the system, MgO-Al,O,—SiO,. J. Petrology, 2, pp. 324-406. SHAW, D. M., 1956. Geochemistry of pelitic rocks. Pt. III. Major elements and general geochemistry. Bull. Geol. Soc. Am., 67, pp. 919-934. SNELLING, N. J., 1957. Notes on the petrology and mineralogy of the Barrovian metamorphic zones. Geol. Mag., 94, pp. 297-304. Spry, A., 1963. The origin and significance of snowball structure in garnet. /. Petrology, 4, pp. 211-222. Metamorphism and migmatization Tvans. Edinb. BRIAN B. GUY TattamM, C. M., 1929. The metamorphic rocks of north-east Victoria. Bull. Geol. Surv. Vict., 52, TILLEy, C. E., 1925. Metamorphic zones in the Southern Highlands of Scotland. Q. J. Geol. Soc. Lond., 81, pp. 100-112. TuRNER, F. J., and VERHOOGEN, J., 1960. Igneous and metamorphic Petrology. McGraw-Hill, New York. VALLANCE, T. G., 1953a. Studies in the metamorphic and plutonic geology of the Wantabadgery-Adelong- Tumbarumba district, N.S.W. I. Introduction and metamorphism of the sedimentary rocks. Proc. Linn. Soc. N.S.W., 78, pp. 90-121. VALLANCE, T. G., 1953b. Idem. III. The Granitic Rocks. Proc. Linn. Soc. N.S.W., 78, pp. 197-220. VALLANCE, T. G., 1960. Notes on metamorphic and plutonic Rocks and their Biotites from the Wanta- badgery-Adelong-Tumbarumba District, N.S.W. Proc. Linn. Soc. N.S.W., 85, pp. 94-104. VALLANCE, T. G., 1967. Palaeozoic low-pressure Regional Metamorphism in South-eastern Australia. Meddr. dansk geol. Foren., 17, pp. 494-503. VENKATESH, V., 1954. Twinning in Cordierite. Miner., 39, pp. 636-646. Wits, G. R., and Woop, J. A., 1949. Mechanism of Creep in Metals. J. Inst. Metals, '75, p. 693. WINKLER, H. G. F., 1965. Petrogenesis of Meta- morphic Rocks. Springer-Verlag, Berlin. YODER, JR., H. S., 1959. Experimental studies on Micas: a Synthesis. Clays Clay Minerals, 6, p. 42-60. Am. Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 197-205, 1968 The Martiniacean Species Occurring at Glendon, New South Wales, the Type Locality of Notospirifer Darwini (Morris) JOHN ARMSTRONG Department of Geology, University of Queensland ABSTRACT—Specimens of three martiniacean species are known from Glendon, the type locality of Notospirifer darwini (Morris). One of these specimens is considered to be conspecific with the lectotype of N. darwini, and others are assigned to Ingelarella Campbell. Specimens ot the third species are thought to be conspecific with ‘“‘ Spirifer’’ duodecimcostatus McCoy which is redescribed. The micro-ornament of each species is highly characteristic and that of the topotype of Notospirifer darwini is identical with the micro-ornaments of species currently included in Notospirifer. It is different from the micro-ornament of the specimen from Glendon which Waterhouse (1967) considered to be a representative of Notospivifer darwint, and which is herein regarded as a possible representative of ‘‘ Spirifer’’ duodecimcostatus. Introduction The lectotype of Notospirifer darwini (Morris) 1845, the type species of the martiniacean genus Notospirifeyr Harrington (1955) is from the Muree Sandstone at Glendon (David, 1907) in the Sydney Basin. However until recently no well preserved martiniacean specimens had been described from the type locality of this species and two critical characteristics of Notospirifer darwint remained incompletely defined. These were the degree of development of the dorsal adminicula and the nature of the micro-ornament of the species. When Harrington proposed the name Notospirifer, he redescribed Notospirifer darwint using plaster replicas of the lectotype and of the second specimen which Morris included in the species. He noted that the lectotype had four low plicae on each of the flanks of the valves and that there is quite a distinct median furrow on the fold. Harrington was unable to comment about the characteristics of the interior of the dorsal valve of the lectotype. Regarding the micro-ornament of Morris’s specimens he quoted a letter from Dr. Helen Muir-Wood, who stated that the specimens show “obscure traces of spines which must have covered the entire surface. I could not make out any details of the spines themselves ”’. Campbell (1959, p. 343) did not consider Morris’s two specimens of Notospirifer darwini to be conspecific or congeneric. He placed _ Morris’s second specimen (BB 6244) in Ingelarella _ Campbell. | Campbell (1959, p. 343) noted that the lectotype of N. darwin has a low ventral umbo, a transverse outline and short divergent ventral adminicula which lie outside the plicae bordering the sulcus. He considered that “dorsal adminicula, if present, must be very short’. Contrary to the findings of Muir- Wood (quoted in Harrington, 1955) Campbell concluded that the surface ornament is not shown on either of Morris’s specimens, and that the structures described as spine bases are the result of irregular decortication of the shell. Unfortunately at the time of his analysis of the Queensland Permian martiniacean species, Campbell was unable to discover any topo- typical specimens of WNotospirifer darwint (Campbell, 1959, p. 343). However, Campbell (1960, 1961) was able to recognise a number of Queensland species essentially lacking dorsal adminicula and he considered that these species. were congeneric with WNotospirifer darwint. Campbell elected to attribute the micro- ornamental characteristics of the Queensland species to Notospirifer, whose micro-ornament was consequently diagnosed as being covered with “deep closely packed subcircular or slightly elongate pits”. All of the Queensland species which Campbell (1960, 1961) placed in Notospirifer are characterised by very sho or non-existent dorsal adminicula. In a paper recently published Waterhouse (1967) figured two well preserved specimens from Glendon. Waterhouse considers one of these specimens (his Pl. 13, Figs. 4~7, 12) to be conspecific with the lectotype of Notospirifer darwimt and the second (his Pl. 13, Figs. 8-11, 198 13) he described as Notospirifer sp. The former specimen possesses short but quite strong dorsal adminicula and a characteristic spinose micro-ornament. This micro-ornament is markedly different from that of Campbell’s Queensland species of Notospirifer and indeed it is more like the micro-ornament of Campbell’s species of Ingelarella and of McCoy’s (1847) species “ Spirifer’’ duodecimcostatus (see later). Waterhouse also notes that if dorsal adminicula are present in the lectotype of Notospirifer darwint they must be very short. A collection made at Glendon in early 1968 yielded a number of martiniacean specimens and these together with Waterhouse’s (1967) figured specimens are divisible into three species. Specimens of one species (Pl. 1, Figs. 8, 10, 11, 12) which is here thought to be conspecific with “ Spirifer’’ duodecimcostatus McCoy are strongly plicate, have a furrow on the fold, and have a variably distinct median plication in the sulcus. They possess ventral adminicula and short but well developed dorsal adminicula. They have a very distinctive micro-ornament of small cylinder-like spines and narrow radially oriented grooves. Each groove runs forward from the anterior side of a spine and remains entirely superficial. Definitely included in this species is the specimen described by Waterhouse (1967) as Notospirifer sp., and doubtfully included is the specimen which Waterhouse (1967) placed in Notospirifer darwint. The second species (Pl. 2, Figs. 5, 6, 7), herein referred to Ingelarella sp. cf. I. angulata Campbell, comprises specimens which are only gently biconvex and which have gently plicate flanks, a broad fold with a median furrow, and a shallow sulcus which bears two low plicae and a median furrow. There are ventral adminicula and moderately to well developed dorsal adminicula. The micro-ornament of specimens of this species is characterised by subquincuncially arranged grooves and very fine concentric lirae. Each of the grooves arises from the front side of a small C-shaped spine. The spines of this species are broader, lower, and less prominent than those of the first species. The third martiniacean species at Glendon is represented by one specimen (Pl. 2, Figs. 1, 2, 3). The specimen has gently plicate flanks, a low flattened fold, and strong ventral adminicula. However it seems to lack developed dorsal adminicula. The micro-ornament of the species is very distinctive and is similar to that of the Queensland species which Campbell (1960, 1961) included in WNotospirifer. The micro- JOHN ARMSTRONG ornament comprises wide, relatively closely spaced grooves which are separated by narrow ridges. At the posterior end of each groove there is a small spinose knob-like protuberance. On the anterior half of the shell of this species the grooves lead antero-internally into small cylindrical pits below the surface of the shell. It is this specimen which is thought to be conspecific with the lectotype of Notospirifer darwint. Mentioned and figured specimens are desig- nated by a number prefixed by several letters which indicate the institution in which the specimen is housed. These are as follows: BB, British Museum (Natural History), London ; AMF, Australian Museum, Sydney; GPC, Commonwealth Palaeontological type collection, Bureau of Mineral Resources, Canberra ; UQF, Department of Geology, University of Queens- land; GSQOF, Geological Survey of Queensland. Localitites indexed at the Department of Geology, University of Queensland and at the Geological Survey of Queensland are nominated by a number prefixed by UQL and GSQL respectively. The only other localities referred to are Bureau of Mineral Resources localities. Details of all of the mentioned localities are given in the appendix. Phylum Brachiopoda Dumeril, 1806 Class Articulata Huxley, 1869 Order Spiriferida Waagen, 1883 Suborder Spiriferidina Waagen, 1883 Superfamily Martiniacea Waggen, 1883 Genus Notospirifer Harrington, 1955 TYPE SPECIES (original designation): S#puirifer darwini Morris (1845) from the Muree Sandstone in the Sydney Basin, New South Wales. D1aGNosis: Shell of variable size, usually wider than long; cardinal extremities rounded ; fold and sulcus present ; flanks plicate; there may or may not be a median furrow on the fold and in the sulcus; micro-ornament on the shell comprises closely spaced relatively wide radially elongate grooves separated by narrow ridges; at the posterior end of each groove at the confluence of the ridges around the groove there is a small spinose knob-lke protuberance ; in three species of Notospirifer the micro-ornamental grooves lead antero- internally into shallow cylindrical pits which penetrate below the surface of the shell but never reach the internal surface of the shell; dental plates and adminicula present in ventral valve; dorsal adminicula either absent or very low and very short. THE MARTINIACEAN SPECIES OCCURRING AT GLENDON, N.S.W. OTHER SPECIES: Notospirifer minutus Campbell, 1960. . hillae Campbell, 1961. . hillae var. plicatus Campbell, 1961. . extensus Campbell, 1961. . extensus var. tweedaler Campbell, 1961. . microstriatus Waterhouse, 1964. (?) N. spinosus Waterhouse, 1965. COMPARISON : Notospirifer generally has a more transverse outline, a lower ventral umbo and less well developed dorsal adminicula than Ingelarella Campbell. The micro-ornament of Notospirifer is distinguished from that of species of Ingelarella by its relatively shorter, wider, more closely spaces grooves. At the posterior end of each groove of the micro-ornament of Notospirifer there 1s a knob-like spinose pro- tuberance. On several species of Notospirifer the superficial grooves lead antero-internally into pits below the surface of the shell unlike the micro-ornamental grooves of Ingelarella. ZZazaS Notospirifer darwimt (Morris) 1845 Plate 2, Figs. 1, 2, 3, 4, 8, 9 Spirifer Darwint Morris, 1845, p. 279. ?Spirifer Darwini Morris; Dana, 1849, Pl. 1, Fig. 7a (non Fig. 7D). non S#irifer Darwint Morris; de Koninck, iene blo. Kies, 11; lia, 115; Pl. 11, Figs. 10, 10a; Pl. 16, Figs. 1, la. non Sfirifera Darwint Morris ; Johnston, 1888, Pao bie. 4, non Martima (vel Martimopsis) Darwini Morris ; Etheridge, 1892, Pl. 39, Figs. 5-7. ?non Notospirifer darwint Morris ; Waterhouse, 1967, Pl. 13, Figs. 4-7, 12. LECTOTYPE (informally designated by Harring- ton, 1955, p. 117 and formalised by Campbell, 1959, p. 343): BB6243 from exposures of the Muree Sandstone at Glendon, New South Wales. The only rock stratigraphic unit outcropping in the vicinity of Glendon Homestead is the Muree Sandstone (David, 1907, pp. 195, 201) which is exposed along the northern bank of the Hunter River just west of the homestead and there is little doubt that this is the type locality for Notospirifer darwin. The lectotype has been figured by Harrington (1955, Pl. 23, Figs. 7, 11, 12 and 14), by Campbell (1959, Pl. 56, Fig. 1) and by Waterhouse (1967, PI. 13, Figs. 1-3). DIAGNOsIS (based on a plaster replica of the lectotype, on Campbell’s (1959, p. 343) remarks about the lectotype, on a comment by Dr. H. 199 Brunton (pers. comm.) of the British Museum (Natural History), and on one other specimen (UQF56154) from the type locality). Shell relatively small and transverse; moderately biconvex; 3 or 4 gentle plications occur on each flank of both valves; sulcus shallow containing two weak plicae and a median furrow ; fold low and broad, bearing a shallow median furrow; ventral adminicula divergent and about one half as long as ventral muscle field; dorsal adminicula non-existent or very Short, low and divergent; micro-ornament comprises closely spaced radially oriented grooves separated by narrow ridges ; at posterior end of each groove is a small spine-like pro- tuberance ; on anterior half of shell grooves lead antero-internally into shallow cylindrical pits below the surface of the shell. DESCRIPTION OF THE SPECIMEN (UQF56154) FROM GLENDON (UQL3262) WHICH IS THOUGHT TO BE CONSPECIFIC WITH THE LECTOTYPE OF Notospirifer Darwini: The specimen comprises internal and external moulds of a shell. The shell is slightly wider than long and is moderately biconvex. There are three low rounded plica- tions on each flank of both valves. The sulcus is very shallow and bears a pair of low plicae, one on each side of a shallow median furrow. The fold is broad and low, producing a gently uniplicate commissural trace. Micro-ornament is quite well preserved on the external mould and it is of the type which is characteristic of the Queensland species placed in Notospirifer by Campbell (1960, 1961). The micro-ornament comprises closely spaced short radially elongate grooves separated by narrow ridges. At the posterior end of each groove there is a low knob-like protuberance. On the adult growth stages of the shell the superficial grooves lead antero-internally into pits below the surface of the shell. On the external mould the infillings of such pits are circumscribed by a succession of growth lines (PI. 2, Fig. 9). In the ventral valve strong ventrally con- vergent dental plates subtend the margins of the delthyrium and are underlain by short divergent adminicula. The latter plates lie along the posterior sides of the field of muscular attachment and are prolonged as low ridges along the antero-lateral sides of this field. Inner socket ridges and their conjoined crural bases are well developed in the dorsal valve, and in the apex of the valve one of the inner socket ridges is underlain by a very short adminiculum. This adminiculum is one or two millimetres long. Details of the muscu- lature of both valves are obscure. 200 REMARKS: Of the three martiniacean species occurring at Glendon the one described above is closest to the lectotype of Notospirifer darwint. Both the lectotype and the above specimen have similar proportions, a low furrowed fold, similar commissural traces, shallow sulci with two low subplicae, and apparently similar dorsaladminicula. On the topotypica: specimen the plications are slightly less well developed. Because of its quite strong divergent dorsal adminicula, its higher fold, its deeper sulcus, its more plicate commissure and its different commissural trace, Waterhouse’s (1967, Pl. 13, Figs. 4—7) specimen of NV. darwinz is not thought to be conspecific with the lectotype of Noto- spirifer darwimt. The micro-ornamentation on Waterhouse’s specimen is quite different from that of the specimen of Notospirifer darwint described here and from the micro-ornaments of the species which Campbell placed in WNoto- spirtfer. DISTRIBUTION : AMF 22792 and AMF24101 from the Gerringong Volcanics at Gerringong, New South Wales are possibly representatives of Notospirifer darwint. The former specimen has three low plications on the flanks of the valves, a low ventral umbo, a broad low furrowed fold and a shallow sulcus which bears two barely discernible subplicae and a median furrow. No micro-ornament is present on the specimen but otherwise it agrees very closely with the specimen of N. darwint from the type locality. The second specimen from Gerringong (PI. 2, Fig. 8) has a slightly higher and narrower fold, but there is no sulcal plication and the micro- ornament is most comparable with the micro- ornament of other Notospirifer species. A specimen (UQF56155) from the Muree Sandstone at UQL3264 is also closest to N. darwint. The specimen is a ventral valve which has a wide flaring sulcus and three low plicae on each flank (Pl. 2, Fig. 4). Ingelarella sp. cf. I. angulata Campbell 1959 Plate 2, Figs. 5, 6, 7, 14, 15 MATERIAL: UQF56156-56160 from the Muree Sandstone at UQL3262, on the northern bank of the Hunter River just west of Glendon Homestead, 6 miles east of Singleton, New South Wales. DESCRIPTION : The shell is gently biconvex and is wider than long. Four gentle plications are visible on each side of the sulcus and three plicae occur on each flank of the dorsal valve. The sulcus is shallow and bears two low plica- JOHN ARMSTRONG tions, one along each side of a median furrow. Correspondingly there is a broad low dorsal fold which bears a distinct median furrow. The commissure is uniplicate. The interior of the ventral vale is characterised by an elongate area of muscular attachment bordered on each side by one of the slightly diverging ventral adminicula. The adminicula reach to about the mid-length of the muscle field. Each adminiculum supports a strong low dental plate. The delthyrium is uncovered and the cardinal margin is non-denticulate. In the dorsal valve there is a pair of adminicula of moderate length. In one specimen (UQF- 56157) they are about seven millimetres long but in two others (UQF56156, 56158) they reach for between one third and one quarter of the length of the valve. The dorsal adminicula lie along or are medially placed with respect to the first plication on each side of the fold. There is a faint median ridge in the dorsal valve dividing the adductor muscle scars which are arranged as in other species of Ingelarella (Campbell, 1959, 1960, 1961). Micro-ornament of this species comprises narrow radially elongate grooves approximately one millimetre long and 10 to 15 times longer than wide. The grooves are widest posteriorly, and taper in the direction of growth of the shell, and are sub-quincuncially arranged. Each one arises on the anterior concave side of a broad low C-shaped spinose protuberance. The grooves are laterally separated by areas generally wider than themselves and on these areas there are very fine concentric lirae which number about 20 per millimetre. REMARKS: Ingelarella sp. cf. I. angulata is distinguished from “ Spirifer’’ duodecimcostatus McCoy by its lower broader fold, by its smoother less plicate flanks, by the chracteristics of its micro-ornament, and because it possesses two low plicae and a median furrow in its sulcus rather than a sulcal plication. Notospirifer darwint lacks the dorsal adminicula of Ingelarella sp. cf. I. angulata and “ Spirifer”’ duodecim- costatus, and it possesses a very distinctive -micro-oranment. The Glendon specimens of Ingelarella are compared with Ingelarella angulata because they are characterised by gently plicate flanks, a shallow sulcus which bears a median furrow bordered by low plications, a low furrowed fold, a uniplicate commissure, and dorsal adminicula of moderate length. The specimens are particularly comparable with topotypical specimens of I. angulata (e.g. UQF56161). THE MARTINIACEAN SPECIES OCCURRING AT GLENDON, N.S.W. “ Spirifer’”’ duodecimcostatus McCoy 1847 Plate 1, Figs. 1-20 ; Plate 2, Figs. 10-13 Spinifer (Brachythyris) duodecimcostata McCoy, 1847, Pl. 17, Figs. 2, 3. Notospirifer sp. B; Dickins, 1966, p. 79. ?Spirifer duodecimcostata McCoy ; Dana, 1849, Pl. 2, Figs. la, 10. ?Spirifer duodecimcostata McCoy ; de Koninck, 1877, Pl. 12, Fig. 4. Spirifer duodecimcostata McCoy; de Konmek, 1877, Pl. 12, Fig. 4a. non Spirifera duodecimcostata McCoy ; Johnston, 1888, Pl. 11, Figs. 2, 4, 9. Spiriferina duodecimcostata Etheridge, 1892, Pl. 44, Fig. 12. non non (McCoy) ; LECTOTYPE (chosen by Waterhouse, 1967, p. 278): E10644 from the Muree Sandstone in the Sydney Basin, New South Wales. The specimens of “ Spirifer’’ duodecimcostatus were sent to McCoy by W. B. Clarke from a location which is given as the “sandstone at Muree”’ by McCoy (1847, p. 320). According to David (1907, p. 200) “‘ the Muree Beds were so called by the late Rev. W. B. Clarke from the typical outcrop in the Muree Quarries at Raymond Terrace’’. The Muree Quarries are located between one and two hundred yards east of the Muree Golf Club clubhouse on Muree Hill in the eastern part of Raymond Terrace, which is on the Pacific Highway just north of New- castle. These quarries are though to be the locality from which Clarke’s specimens of “ Spirtfer”’ duodecimcostatus were collected. The lectotype was figured by McCoy (1847) in his Plate 17, Figure 2 and a plaster replica of it is figured again in Plate 1, Figures 1 and 2. DESCRIPTION OF THE LECTOTYPE (based on a plaster replica of McCoy’s specimen): The specimen is moderately biconvex and is wider than long. It has rounded cardinal extremities and a uniplicate commissure. The ventral umbo is prominent and is the most strongly convex part of the shell. On each flank of the ventral valve there are six strong plications and one very small plica. The sulcus is moderately narrow and deep and it has a distinct median plication. At least five and possibly six plica- tions occur on each flank of the dorsal valve. It is not possible to say whether or not a median furrow was present on the fold because of the poor preservation of this part of the specimen. However the fold is quite narrow and high. No micro-ornamental or internal features of the specimen are visible. 201 The second of McCoy’s specimens (McCoy, 1847, Pl. 17, Fig. 3; E10645) of “ Spirtfer” duodecimcostatus 1s a dorsal valve on each flank of which there are five strong plications. On the fold of the specimen there is a distinct median furrow. A collection made from the Muree Quarries contains a number of specimens similar to and probably conspecific with McCoy’s specimens. DESCRIPTION OF 5 TOPOTYPICAL SPECIMENS (UOF56162-5616€) oF “ Spirifer’’ duodecim- costamus McCoy FROM THE MUREE QUARRIES (UQL3264): The first specimen (UQF56162) comprises internal and external moulds of a dorsal valve. On each flank of the valve there are four strong plications. The fold is broad and bears a distinct median furrow. The sediment in which this and the other specimens from the Muree Quarries are preserved is quite coarsely grained and is very friable. Thus the dorsal cardinalia of this specimen are poorly preserved and cannot be detailed. Similarly the micro-ornament on the external surface of the shell is very obscure. On some parts of the external mould there are impressions of the micro-ornamental features. These suggest that the micro-ornament consisted of narrow radially elongate grooves in quincunx. At the posterior end of some of the grooves there appears to have been asmall protuberance. It has not been possible to figure the specimen’s micro-ornament but in all essential respects it is identical with the micro-ornaments of similar specimens from Glendon (see below). The second specimen (UQF56163) is an internal mould of a dorsal valve which has three plicae on each flank and a strong median furrow on the fold. Dorsal adminicula of the specimen are located on the first plication adjacent to the fold. The third specimen (UQF56164), an internal mould of a part of a dorsal valve also shows adminicula about 1/5 as as long as the valve located along the plicae adjacent to the fold. As before the fold is furrowed and there are a number of strong plica- tions on each flank. UQI56165 is also an internal mould of a dorsal valve on which there are four plicae on one flank and five on the other. The fold is quite high and narrow and bears a median furrow. The last specimen (UQF56166) which is thought to be a repre- sentative of ‘ Spirifer’’ duodecimcostatus is an internal mould of half of a dorsal valve. The fold is high and furrowed and on the right flank there are four plications. Adminicula are quite strongly developed, being located in 202 the second interplical furrow adjacent to the fold and extending for about one fifth of the length of the valve. Unfortunately no ventral valves definitely comparable with the lectotype of “ Spirifer”’ duodecimcostatus were collected from the Muree Quarries. The dorsal valves described above are inseparable from McCoy’s two specimens. On a number of the flanks of the specimens there are one or two fewer plicae than there are on McCoy’s specimens but no consistent differences can be detailed. Moreover specimens with a sulcal plication trom the Muree Sandstone at Glendon show quite varying degrees of develop- ment of the lateral plicae. Of the three martiniacean species from Glendon which are mentioned in the introduction it is the first one whichis here sreterreds co “ Shirifer’’ duodecimcostatus. The specimens from Glendon are better preserved than the specimens considered to be topotypes of “ Shirifer ’’ duodecimcostatus and for this reason they’ “are completely ‘described. ~Dhe™ ten (UOF56167-56176) quite well preserved specimens from Glendon are _ referred to “ Sdirifer’’ duodecimcostatus because super- ficially they are inseparable from the lectotype and because their dorsal adminicula and their micro-ornament are virtually identical with the dorsal adminicula and micro-ornament of the topotypes of “ S”’. duodecimcostatus described above. DESCRIPTION OF SPECIMENS OF “ Spirifer”’ duodccimcostatus FROM GLENDON: The shell is relatively small and in general it is wider than long. Both valves bear plications and there are from four to six strong plicae on each flank. There is a moderately high fold with a distinct median furrow, and in the sulcus there is a median plication. The areas of the valves are ornamented with grooves and ridges both parallel to and transverse to the direction of growth. The surface of the shell shows several prominent growth lamellae and it bears a micro-ornament of very small cylindrical spines and fine radially elongate grooves. Each of the grooves runs forward from the front of a spine (Pl. 2, Figs. 10-13). In the ventral valve there are well developed dental plates and adminicula. The latter plates are slightly divergent and reach to about the mid-length of the muscle-fleld, which is narrow and elongate. There is no thickening in the umbonal cavities or the delthyrial cavity of the ventral valve. Similarly there is no thickening JOHN ARMSTRONG in the posterior part of the dorsal valve. Inner socket ridges are well developed and from them arise the crural bases. Underlying each of the crural bases is a robust adminiculum. The dorsal adminicula are about one fifth as long as the valve and are slightly divergent. They lie below either the first plication or the second lateral furrow on each side of the fold. The cardinal process is small and it comprises a series of longitudinally oriented plates. DISTRIBUTION: Transverse specimens charac- terised by the above features are known from a number of localities throughout eastern Australia. The species occurs in the Muree Sandstone at the Muree Quarries and at Glendon. Specimens from the Gerringong Volcanics (UQF- 5614, UQF56177-56182, AMF24073, and AMF- 24103) and from the base of the Nowra Sandstone (UQOF56183-84) on the South Coast of New South Wales belong-.to the “species, The specimens from the Gerringong Volcanics are quite transverse with four or five plicae on each flank of their valves, a median sulcal plica- tion and the characteristic dorsal adminicula. Adminicula in the dorsal valves of specimens from Gerringong lie in the second furrows away from the fold. A specimen (AMF14123) from Bundanoon Gully, 700 feet below the site of Tooth’s old sawmill, 2 miles south of Bundanoon Railway Station is also conspecific. An internal mould of part of a dorsal valve (CPC9908) from the Branxton Formation at HV16 has several plicae on the flanks and dorsal adminicula lying outside the first lateral plicae like other specimens of “S”. duodecimcostatus. It is probably conspecific. A similar specimen (CPC- 9909) is known from HVla in the Fenestella zone of the Braxton Formation. This specimen is an internal mould showing the characteristic sulcal plication and widely divergent dorsal adminicula. An internal mould of a ventral valve (UQF56187) whose locality is given as Merlya Pass, Kangaroo Valley, South Coast of New South Wales is characterised by a sulcal plication and four strong plicae on each flank, and is a probable representative of “S”. duodecimcostatus. An external mould (UQF49596) of a ventral valve from the Malbina Formation (Member EF) is closest to “ Spirifer’’ duodecimcostatus and a small internal mould (UQF56185) from the same unit may also belong to the species. In Queensland the species is known from the “Big Strophalosia Zone” (UQF56186 from UQL3134) and from locality M416. It also occurs in the base of the Gebbie Formation at GSOLD28. Several specimens (GSQF10553, THE MARTINIACEAN SPECIES OCCURRING AT GLENDON, N.S.W. 11039, 11043-45) from locality GSQLD28 are quite transverse and display the high furrowed fold, a sulcal plication, strongly plicate flanks, and the dorsal adminicula characteristic of “ S”’. duodecimcosiatus. GENERIC ASSIGNMENT: “ Spirifer’’ duodecim- costatus is placed neither in Notosfirifer nor in Ingelarella because of its very distinctive micro- ornament and its sulcal plication. It is one of a number of eastern Australian Permian martiniacean species characterised by these features and when these species are fully understood they will probably necessitate recog- nition of a new martiniacean genus. REMARKS: The specimen from Glendon figured by Waterhouse (1967) in Plate 13, Figures 8-11, 13 is definitely a representative of ‘‘ Spirifer”’ duodecimcostatus. The specimen possesses the dorsal adminicula, relatively high furrowed fold, plicate flanks, and distinctive micro- ornament of the species. The affinities of the specimen which Waterhouse (1967, Pl. 13, Figs. 4—7) placed in Notospirifer darwini are less readily established. The specimen possesses dorsal adminicula developed to the same extent as the adminicula of the specimens of “S”’. duodecimcostatus from Glendon. It has a rela- tively high furrowed fold and its micro-ornament is identical with that of specimens of “S”’. duodecimcostatus from Glendon and_ other localities. However the specimen lacks a distinct sulcal plication and there are faint traces of two very weak sulcal plicae. It seems to have been mainly on the basis of the last mentioned point that Waterhouse placed the specimen in WNotospirifer darwini. However Dr. H. Brunton (pers. comm.) of the British Museum (Natural History) suggests from an examination of the dorsal valve of the lectotype of N. darwini that the valve lacks adminicula but has very short ridges only one or two millimetres long. Moreover the anterior trace of the fold of the lectotype is lower and broader than that of Waterhouse’s specimen of N. darwint. On the basis of its dorsal adminicula, fold, and micro-ornament, Waterhouse’s specimen is thought to be more closely allied to “ Spirifer”’ duodecimcostatus than to Noto- spirifer darwint. However the specimen is small and whether or not it is conspecific with the former of these species is uncertain. Summary Glendon, New South Wales is probably the type locality of Notospirifer darwint (Morris) the type species of Notospirifer Harrington. A 203 martiniacean specimen from exposures of the Muree Sandstone at Glendon is considered to be a topotype of Notospirifer darwim. The micro-ornament on the specimen is particularly characteristic, and all but one of the Queensland martiniacean species included in WNotospirifer by Campbell (1960, 1961) possess this type of micro-ornament. Waterhouse (1967) has figured a specimen from Glendon which he considers to be a representative of N. darwint. However in several respects this specimen is distinguishable from the lectotype of N. darwint and from the topotype of this species described herein. The micro-ornament of Waterhouse’s specimen is identical with the micro-ornaments of other Glendon specimens which are here considered to be representatives of “‘ Spirifer”’ duodecimcostatus McCoy. However although Waterhouse’s specimen of N. darwint has more features in common with “ Spirifer’”’ duodecim- costatus than it has with the lectotype of N. darwint, the specimen is small and there is uncertainty as to whether or not it is con- specific with McCoy’s species. References CAMPBELL, K. S. W., 1959. The Martiniopsis-like spiriferids of the Queensland Permian. Palaeon- tology, 1(4), pp. 333-350. CAMPBELL, K. S. W., 1960. The brachiopod genera Ingelarella and Notospirifer in the Permian of Queensland. J. Paleont., 34, pp. 1106-1123. CAMPBELL, K. S. W., 1961. New species of the Permian spiriferids IJngelarella and Notospirifer from Queensland and their stratigraphic implica- tions. Palaeontographica, 117(A), pp. 159-191. Dana, J. D., 1849. In United States Exploring Expedition during the years 1838-42, under the command of Charles Wilkes, U.S.N., 10, Geology, pp. 681-7138. Davin, T. W. E., 1907. The geology of the Hunter River Coal Measures, New South Wales. Mem. geol. Surv. N.S.W., 4. Dickins, J. M., 1966. Appendix 7m Matong, E. J., JENSEN, A. R., GreEGory, C. M., and FoRBEs, V. R., 1966. Geology of the southern half of the Bowen 1: 250,000 sheet area, Queensland. hep. Bur. Miner. Resour. Geol. Geophys. Aust., 100. ETHERIDGE, R., JR., 1892. ETHERIDGE, R., 1892. tology of Queensland and New Guinea. geol. Surv. Qd., 92, pp. 1-768. HARRINGTON, H. J., 1955. The Permian Eurydesma fauna of eastern Argentina. J. Paleont., 29, pp. 112-128. Jounston, R. M., 1888. geology of Tasmania. Govt. Pr., Hobart. Konincx, L. G. DE, 1876-7. Recherches sur les Fossiles Paleozoiques de la Nouvelle-Gailes du Sud (Australie). Mem. Soc. r. Su. Liege, Ser. 2, 6, 7, pp. 1-873. (English translation by Davin, T. W. E., et. al., Mem. geol. Surv. N.S.W., Palaeontology, 6, 1898). In Jack, R. L., and The geology and palaeon- Publ. Systematic account of the 204 McCoy, F., 1847. On the fossil botany and zoology of the rocks associated with the coal of Australia. Ann. Mag. Nat. Hist., Ser. 1, 20, pp. 145-157 ; 226-236 ; 298-312. Morris, J., 1845. In STRZELECKI, P. E. DE, 1845. Physical description of New South Wales and Van Dieman’s Land. London, pp. 270-289. WATERHOUSE, J. B., 1964. Permian brachiopods of New Zealand. Bull. geol. Surv. N.Z. Palaeont., 35, pp. 1-287. WATERHOUSE, J. B., 1965. The Permian spiriferoid genus Ambikella Sahni and Srivastava (1956) and its relationship to Ingelarella Campbell (1959) and Martiniopsis Waagen (1883). Trans. roy. Soc. N.Z. Geol., 3, pp. 159-170. WATERHOUSE, J. B., 1967. The ornament of the Permian brachiopod Notospirifer Harrington, 1955. J. geol. Soc. Aust., 14, pp. 273-280. Appendix Following are details of the localities referred to in the: text. UQL2788: Black Head, Gerroa, 2 miles south of Gerringong. Gerringong Volcanics. UQL3065: Beach below cliffs immediately east of Shot Tower, Taronga, Hobart, Tasmania. Malbina Formation (Member E). UQL3098: In Dry Creek about 1-5 miles from its confluence with Carnarvon Creek. Eddystone 1: 250,000 map, 148° 17-5’ E., 25° -5’S. Peawaddy Formation. JOHN ARMSTRONG UQL3134 : UQL3155 : UQL3262 : UQL3264 : GSQLD28 : HVla: HV16: M416: On track about 1 mile west of Mulgrave Yards west of Parrot Creek, west of Havilah Homestead. Bowen, 1 : 250,000 map, 147° 42’E., 20°50’S. Big Stro- phalosia Zone. Road cutting on Pointer Gap road, Milton, South Coast of New South Wales. Base of Nowra Sandstone. Northern bank of Hunter River just west of Glendon Homestead, 6 miles east of Singleton, New South Wales. Muree Sandstone. Small quarries on Muree Hill between 100 and 200 yards east of the Muree Golf Club clubhouse. Muree Hill is in the eastern part of Raymond Terrace on the Pacific Highway just north of Newcastle, New South Wales. Muree Sandstone. The eastern bank of Bowen River near Exmoor Homestead. Base of Gebbie Formation. Railway cuttings between 1,100 and 1,600 yards west of Branxton Station. Fenestella zone in Branxton Formation. In Redhouse Creek about half a mile east of junction of Dalwood Road with New England Highway, at junction with small tributary. Singleton 1 : 250,000 map, 438 E., 963 N. Branxton Forma- tion. Mackay 1: 250,000 map, ym Waa A POL sorsy 148° 30’ E., AKMST RON G i? TA ia WOURNAL ROYAL SOCIETY N-oS.W. ARMSTRONG PLAT ERG WOURNAL ROYAL SCCTETY IN Si. WS THE MARTINIACEAN SPECIES OCCURRING AT GLENDON, N.S.W. 205 Explanation of Plates PLATE 1 Figures natural size unless stated. Figs. 1-2—“ Spirifer’”’ duodecimcostatus McCoy. E10644. Ventral and anterior aspects respectively of a plaster replica (UQF10702) of the holotype. Fig. 3—“ Spirifer’’ duodecimcostatus McCoy. E10645. View of plaster replica (UQF10710) of second of McCoy’s specimens. Fig. 4—“ Spirifer’’ sp. cf. “ S.’’ duodecimcostatus McCoy. x2. UQF56185. Postero-dorsal view of internal mould from the Malbina Formation (Member E) at UQL3065. Figs. 5-7—“ Spirifer’’ duodecimcostatus McCoy. UQF56164, UQF56165, and UQF56166 respectively. Internal moulds of three dorsal valves from exposures of the Muree Sandstone in the Muree Quarries (UQL3264). Figs. 8-9—“ Spirifer’”’ duodecimcositatus McCoy. 8, UQF&6168. Anterior view of internal mould from the Muree Sandstone at UQL3262. 9, AMF20473. Anterior view of shell from the Gerringong Volcanics at Gerringong. Figs. 10-11—“‘ Spivifer’’ duodecimcostatus McCoy. UQF56167. Dorsal and ventral aspects of internal mould from the Muree Sandstone at UQL3262. Fig. 12—“ Spirifer’’ sp. cf. “ S.” duodecimcostatus McCoy. UQF56169. Internal mould of ventral valve from the Muree Sandstone at UQL3262. Fig. 13—“ Spirifer’’ duodecimcostatus McCoy. AMF14123. Internal mould of dorsal valve from Bundanoon Gully, New South Wales. Figs. 14-15—“ Spirifer’’ duodecimcostatus McCoy. 14, GSQF11039. Postero-dorsal view of an internal mould from the base of the Gebbie Formation at GSQLD28. 15, GSQFIJ1044. Internal mould of ventral valve from the same locality as GSQF11039. Fig. 16—“ Spirifer’’ sp. cf. “‘ S.’ duodecimcostatus McCoy. UQF49596. Cast of external mould of ventral valve from the Malbina Formation (Member E) at UQL3065. Fig. 17—‘‘ Spinifer’’ sp. cf. ‘ S.’’? duodecimcostatus McCoy. UQF56183. Interna mould of ventral valve from base of Nowra Sandstone at UQL3155. Figs. 18-20—“ Spirifer ’’ duodecimcostatus McCoy. 18, AMF24103. Ventral aspect of shell from the Gerringong Volcanics at Gerringong. 19, 20, UQF5614, UQF56177 respectively. Internal moulds of dorsal valves from the Gerringong Volcanics at Gerringong. PLATE 2 Figures natural size unless stated. Figs. 1-3—Notospirifer darwini (Morris). UQF56154. Posterior, ventral, and anterior views respectively of an internal mould from the Muree Sandstone at UQL3262. Fig. 4—WNotospirifer sp. cf. N. darwini (Morris). UQF56155. Ventral valve from Muree Sandstone at UQL3264. Figs. 5-—7—Ingelarella sp. cf. I. angulata Campbell. 5 and 7, UQF56157. Dorsal and anterior aspects respectively of an internal mould from the Muree Sandstone at UQL3262. Fig. 8—Notospirifer sp. cf. N. darwini (Morris). AMF24101. Dorsal valve of specimen from Gerringong Volcanics at Gerringong. Fig. 9—Notospirifer darwini (Morris). x10. UQF56154. External mould of micro-ornament of shell showing sediment infillings of the pits on the external surface of the shell. Same specimen as in Fig. 1. Figs. 10-13—“ Spirifer’’ duodecimcostatus McCoy. 10, x13. UQF56167. Cast of micro-ornamental spines and grooves. ll, x13. UQF56168. Cast of micro-ornamental spines, grooves, and concentric lirae. 12, x25. UQF56167. Portion of micro-ornament in Fig. 10. 13, x17. UQF56167. Cast of micro- ornamental spines and grooves. The specimens are from the Muree Sandstone at UQL3262. Figs. 14-15—Ingelarella sp. cf. I. angulataCampbell. Both x16. UQF56157. Casts of micro-ornament showing small spine-like protuberances, grooves, and concentric lirae. Same specimen as in Fig. 5. Journal and Proceedings, Royal Society of New South Wales, Vol. 101, pp. 206-207, 1968 Book Review The Logic of Special Relativity. By S. J. Prokhovnik. More than 60 years have elapsed since the appearance of Einstein’s epoch-making article in the Annalen der Physik, on the electro- dynamics of moving bodies. In the intervening years relativity became an integral part of our physical world picture, penetrating almost all aspects of contemporary physics, from school teaching to the most sophisticated realms of quantum mechanics. Yet even today there is no universally accepted agreement on the exact standing of the theory within the general frame- work of physics and the correct interpretation of its assertions. Some regard relativity as an all-embracing theory of space and time which has influenced our ways of thinking about the physical Universe more deeply than almost any other single physical theory in the history of science. Others regard relativity merely as a technical device involving forma] manipulations with Lorentz transformations and adding little (Gif anything at all) to our knowledge of the physical Universe beyond what is laid down in the equations of these transformations. Further down the scale there are those who reject altogether the basic assumptions and experimental foundations of the theory which they regard as wholly inadequate. The philosophical implications of relativity have been examined by numerous writers from Bergson to Whitehead, but no one has yet attempted a comparative survey of the current physical interpretations and controversies arising from these interpretations. Prokhovnik’s “The Logic of- Special Relativity ” is therefore a welcome and important addition to the volu- minous literature on relativity. The title of the book must not be taken too literally ; it is not so much the logic of the theory itself but that of its numerous contributors which is under scrutiny. This is particularly true of the discussion of the notorious clock paradox which appears in some form or other in nearly every chapter of the book. The author gives a faithful account of the Dingle-McCrea—Builder controversy without committing himself explicitly in either way. He gives a clear exposition of the paradox itself and the arguments surrounding it, making extensive use of a diagrammatic device due to Arzelies. One point on which the exposition is not very clear is the exact meaning of the term “absolute ’’ when applied to time dilata- tion and similar effects. In a sense any observ- able effect (such as the mass-energy relation or the relativistic Doppler-effect) is absolute, and it is hardly surprising that relativity does produce such effects—it would be a disaster if it would not. Paradoxically, the chapter which the reviewer has found most interesting is the one on absolute motion in which the author takes a more definite personal stand and in which the clock paradox is only marginally touched upon. This of course is a chapter to which the author himself has made substantial original contri- butions and he gives an excellent account of how the theory of (special) relativity looks like if the existence of a distinguished reference frame or state of absolute rest is assumed. For the cosmologist it is hardly necessary to stress the intrinsic interest of such an approach since he is anyhow forced to accept an absolute inertial frame, corresponding to the state of motion of the substratum relative to which the Universe appears to be isotropic. The “ logic of absolute motion ”’ rests on two assumptions : (a) There exists a distinguished frame of reference in which the propagation of energy is isotropic. (6) Movement of a body relative to the distinguished frame is associated with a single effect, the Lorentz-Fitzgerald contraction. These two postulates and Einstein’s con- ventions on synchronization suffice to deduce the whole fabric of relativistic kinematics. Of course in terms of absolute time, that is time synchronized with respect to the distinguished observer, light propagation becomes unisotropic when the observer is in motion, but the anisotropy effects cancel out in Michelson-Morley type experiments and the net result is the same as in conventional relativity. There are definite advantages in this approach even for those not interested in cosmology. All relativistic “‘ paradoxical ’”’ effects are reduced BOOK REVIEW to a single easily visualizable physical effect, namely contraction in the direction of motion, and the clock paradox is quite easily resolved, in favour of the conventional (non-Dingle type) solution. Another great advantage is that extension to 3-space, usually a cumbersome and dubious procedure, is achieved here with remarkable ease. Against these advantages the orthodox relativist might argue that (i) the distinguished state of motion does not show up in local (non-cosmological) observations, that is, in precisely those phenomena to which special relativity normally applies; (ii) there is an artificial anisotropy introduced into the theory which again does not show up in local observa- tions; (ili) the second postulate (B) appears to be quite arbitrary in comparison with the usual Einstein postulates of which of course it is a consequence. The first two objections are to some extent removed in the last chapter where yet another 207 postulate (McCrea’s light-hypothesis) is intro- duced in order to meet cosmological require- ments. On the cosmological scale _ the distinguished frame does show up in concrete physical effects, but this is only to be expected since the extended system is equivalent to a certain general relativistic model. The third objection cannot really be dispelled on physical grounds alone since the answers given by the new approach are identical (locally) with those given by orthodox relativity. It is the individual’s outlook towards laws of nature in general which will ultimately determine his stand towards Prokhovnik’s case for the ether. Perhaps the greatest single merit of this book is that it brings home more vividly than any previous writing the fact that relativity is perfectly consistent with an ether-like hypothesis and that our acceptance or rejection of such a hypothesis is a matter of taste rather than of substance. G. SZEKERES. AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. 71-79 ARUNDEL ST., GLEBE, SYDNEY, N.S.W., 2037 CONTENTS Part 1 The Liversidge Lecture: Organic Metals? The Electrical Conductance of Organic Solids. L. E. Lyons Biology : Abiogenesis Leading to Biopoesis. Krishna Bahadur and Indra Saxena Hydrogeology : . Acquifer Water Resistivity—Salinity Relations. D. W. Emerson Geology : The Stratigraphy of the Putty-Upper Colo Area, Sydney Basin, N.S.W. M. C. Galloway Report of the Council, 31st March, 1967 - = Balance Sheet 7 Rules of the Royal Society a New Sotth wales By-Laws of the Royal Society of New South elles Part 2 Astronomy : Precise Observations of Minor Planets at Sydney See ately, ae 1965 and 1966. W. H. Robertson ; 3 Minor Planets Observed at Sydney Operators eee 1967. W. H. operon Geophysics : Magnetic Studies of the Canobolas Mountains, Central Western New South Wales. R. A. Facer = = oe - ie = a e 5 ca Geology : Some Blockstreams of the Toolong Bem Ee Kosciusko State Park, New South Wales. N. Caine and J. N. Jennings sas - Mesozoic Geology of the Gunnedah- ene etch ii Be Dany The Petrography of a Coal Seam from the ei. River Coal Measures, Ph Rivet =r Gorge iN: A. CG. Gook and H. W. Read Parts 3-4 Medicine : The Film Badge Service in New South Wales. A. W. Fleischmann Geology : A Tesselated Sandstone Platform, Ku-ring-gai Chase, N.S.W. D. F. Branagan Presidential Address (1967) : Geological Techniques. Alan H. Voisey .. Geology of the Narooma Area, N.S.W. C. J. Walon ~ hs The Geology of the Manildra District, New South Wales. N. M. Savage Mesozoic Stratigraphy of the Narrabri-Couradda District. J. A. Dulhunty Progressive and Retrogressive Metamorphism in the Tumbarumba-Geehi District, N.S. W. Brian B. Guy The Martiniacean Species Oeeine at eiendon Neg South ales. tise Type Locality 0 of Notospirifer darwint (Morris) John Armstrong lil 11 17 23 37 42 53 59 65 73 7 93 105 109 119 129 137 147 159 179 183 197 IV CONTENTS Mathematics : A Note on Convex Distributions. James L. Griffith Presidential Address (1968) : Initial Value Problems in Two-Dimensional Water Wave Theory. A. H. Low Book Review : Review of “‘ The Logic of Special Relativity ’’, by S. J. Prokhovnik. G. Szekeres .. Index to Volume 101 List of Office Bearers, 1967-1968 : 135 171 206 208 ll INDEX Page A Abiogenesis Leading to Biopoesis, by Krishna Bahadur and Indra Saxena 11 Abstract of Proceedings, 1966 39 Annual Report, 1967. at Annual Report of the New England “Branch 46 Aquifer Water Resistivity—Salinity Relations, by DW. Emerson .. 17 Armstrong, John—The Matiniacean " “Species Occurring at Glendon, New South Wales, the Type mee of RENE darwint (Morris) Peoa lo. Astronomy 65, 73 B Bahadur, Krishna and I. Saxena—Abiogenesis Leading to oa iS Balance Sheet. 42 Biology es te all Book Review .. . 206 Branagan, D. PN Areséclated Sa ticone Plat- form, Ku-ring-gai Chase, N.S.W. 129 By-Laws of the Royal Society of New South Wales 59 C Caine, N. and A. N. Jennings—Some Blockstreams of the Toolong Range Kosciusko State Park, New South Wales 93 Canobolas Mountains, Cantal eon Ne ew Senin Wales. Magnetic Studies of the, 2 ke A Facer d es : did Christie, Thelma Isabel—Obituary, AT Citations : : 51 Clarke Medal for 1967. : 51 Clyde River Coal Measures, “Clyde River Gorge, N.S.W. The Petrography of a Coal Seam from, by A. C. Cook and H. W. Read «. LO9 eonvex Distributions. A Note on, by J. L. Griffith .. 135 Book, C. A. and H. ‘W. Read—The Petrography of a Coal Seam from the Clyde River Coal Measures, Clyde River Gorge, N.S.W. 109 D Oulhunty, J. A. = Mesozoic Geology of the Gunnedah- Narrabri District 105 Mesozoic Stratigraphy of ‘the Narrabri- Couradda District . 179 E Edgeworth David Mcdal for 1966 .. ie, D2 mmerson, D. W.—Aquifer Water Resistivity- Salinity Relations ne ify Page F Facer, R. A.—Magnetic Studies of the Canobolas Mountains, Central Western New South Wales 54 te hs Fairley, Sir Neil Elavil tone Onrnaey . 47 Film, Badge Service in New South Wales, The, by A. W. Fleischmann .. 119 Fleischmann, A. W.—The Film Badge Genjce in New South Wales 119 G Galloway, M. C.—The Stratigraphy of the Putty- Upper Colo Area, Sydney Basin, N.S.W. .. 23 Geological Techniques. Presidential Address ey IN H. Voisey 137 Geology 23, 93, 105, 109, 129; “137, 147, 159, 180, 183, 197 Geology, Section of 45 Geology of the Manildra oes oy N. M. SSaaaee 159 Geology of the Narooma Area, New South Wales, by C. J. L. Wilson . 147 Geophysics re : a7 ae a INCOSW 3 Martiniacean Species Occurring na by J. Armstrong 197 Griffith, J. L—A Note on Convex Distaittion: 135 Guy, B. B.—Progressive and Retrogressive Meta- morphism in the Tumbarumba-Geehi District, N.S.W. 183 Gunnedah-Narrabri pees tiiecozeic Geology . the, by J. A. Dulhunty.. 105 H Hydrology... La a a Be ely I Initial Value Problems in Two-dimensional Water Wave eee Presidential Address a ite tale Low Soi J James Cook Medal for 1966 se f - ol Jennings, J. N., see Caine, N. 93 K Kenny, J.—Obituary - a ade : 47 Ku-ring-gai Chase, N.S.W. A Tesselated Sand- stone Platform, by D. F. Branagan «L239 INDEX Page L Leach, Stephen L.—Obituary ie a sen 49 Liversidge Research Lecture, 1966. Organic Metals ? The _ Electrical Conductance of Organic Solids, by L. E. Lyons 1 Logic of Special Relativity—Book Review by G. Szekeres 206 Low, Angus H.—lInitial Value Problems in Two- Dimensional Water Wave Theory. Presi- dential Address, 1968 .. oh Ly, ee br Lyons, L. E.—Organic Metals? The Electrical Conductance of Organic Solids. Liversidge Research Lecture, 1966 ae te em: 1 M Magnetic Studies of the Canobolas Mountains, Central Western New South Wales, by RA. Pacer is se Se a sist ad Martiniacean Species Occurring at Glendon, NGS: Wis) by J. pues aah Or Mathematics ; oh cs 135,17 Medallists, 1967-— 1968 ey ae 3. veh Oil Medicine ae ds os WLS Meldrum, Henry Ne —Obituary oe a8 Ja BO Mesozoic geology of the Gunnedah-Narrabri District, by, j. 3s 171 Progressive and Retrogressive Metamorphism in the Tumbarumba-Geehi District, New South Wales, by 5. B.Guy = Putty-Upper Colo Area, Sydney Basin, N. S.W., The Stratigraphy of the, by M. C. Galloway 23 183 R Ranclaud, Archibald B. B.—Obituary .. eeraimes |) Read, H. W., see Cook, A. C. Review, Book—The Logic of Special Relativity by S. J. Prokhovnik—reviewed by G. Szekeres 206 Robertson, W. H. Precise Observations of Minor Planets at Sydney Observatory during 1965 and 1966 65 Minor Planets Observed at Sydney Observa- tory during 1967 .. Seen: Rules of the Royal Society of New South Wales. 53 S) Savage, N. M.—The Geology of the Manildra ister New South Wales . 159 Saxena, Indra, see Krishna Bahadur bar oe Society's Medal for 1966... yt Some Blockstreams of the Toolong Range Kos- ciusko State Park, New South Wales, by N. Caine,and J. N. Jennings: 93 Stratigraphy of the Putty-Upper Colo Area, Sydney Basin, N.S.W., by M. C. Galloway . 23 Sydney Observatory 65, 73 szekeres, G. Review ‘of The Logic of Relativity, by S. J. Prokhovnik 206 T Tesselated Sandstone Platform, Ku-ring-gai Chase, N.S.W., by D. F. Branagan, -~. 129 Toolong Range Kosciusko State Park, New South Wales, Some Blockstreams of the, by N. Caine and J. N. Jennings E 93 Tumbarumba-Geehi District, INES: W., Progressive and Retrogressive Metamorphism im the; by B. B: Guy. ; ae . 183 V Voisey, A. H.—Geological eae Presi- dential Address, 1967 . ; ee L3G W Watts, Arthur Spencer—Obituary 50 Wilson, C. J. L.—The Cooley of the Narooma Area, N:S:.W: =. . 147 re Sipe President ea ete ea NS ene NCA! Sy oe H, ‘Low, Ph.D. noe se Se ee 7 eee 27Ny AX 4 ‘ oar ros arose ENN Se ae aie > Ck He OE. D.Sc. : Honorary | Secretaries oe a re ae A REICHEL, Ph. D. M. Su oe Re mes he, Asc) ex \ ats ey ope B. “LINDSAY, B sae M. re D. Phil, aa en Ww. G. ‘NEUHAUS, M.Sc. 5% ee te - J. P. POLLARD, ‘Dip.App.chem, ne. oa PUTTOCK, B.sc. (Eng.), ALINStP. Sy, Sea at ROBERTSON, Bs. ee ! : si nf ? as Sit ea » re g | Leg aa = x 4y. ¥ aS i A ‘So =) A, QD Ss (es) n) W S URNAL ROYAL SOCIETY N JO LOWER DEVONIAN CONODONTS FROM LICK HOLE LIMESTONE 9 References Apamson, C. L., 1954. Tech. Rep. Mines Deft. N.S.W., 2, 7-15. Apamson, C. L., e al., 1966. Australian 1 : 250,000 Geological Series, Sheet SI 55-15, Wagga Wagga. ANDREWS, E. C., 1901. Geol. Surv. N.S.W. Min. Res., 10, 1-32. Benson, W. N., 1922. Rec. Geol. Surv. N.S.W., 10, 83-204. Branson, E. B., AND Ment, M. O., 1933. Univ. Missouri Studies, 8, 1-156, pls. 1-12. Dun, W. S., 1902. Ann. Rep. Mines Dept. N.S.W.., 175. HarPER, L. F., 1912. Ann. Rep. Mines Dept. N.S.W.., 179. JAcQuET, J. B., 1918. Ann. Rep. Mines Dept. N.S.W.., 74-76 MOoSKALENKO, T. A., 1966. Paleont. Zhurnal, 2, 81-92, pls. II, text-figs. 1-4. Move, D. G., SHARP, K. R., AND STAPLEDON, D. H., 1963. Geology of the Snowy Mountains Region, 1-66. Snowy Mountains Hydro-electric Authority, Cooma, Australia. PEDDER, A. E. H., Jackson, J. H., AND PHILIP, G. M., 1969. J. Paleont. (at press). Puitip, G. M., 1966. Micropaleontology, 12, 441-460, pls. 1-4. PuHitip, G. M., AND JACKSON, J. H., 1967. 41 (5), 1262-1266. J. Paleont., (Received 27 Proc. 3rd Boundary. PHILIP, G. M., AND Jackson, J. H., 1970. Intern. Symp. Silurian-Devonian Leningrad, 1968. RuHopvEs, F. H. T., 1953. Roy. Soc. London, Philos. Trans., Ser. B, 237 (647), 261-334, pls. 20-23. SHERRARD, K., 1967. Proc. Roy. Soc. Vict., 80 (20), 229-246, pls. 37-38. STAUFFER, C. R., 1938. pls. 48-53. WALLISER, O. H., 1957. Nofizbl. hess. Bodenforsch., 85, 28-52, pls. 1-3. WALLISER, O. H., 1964. Abh. hess. Landesamt Boden- forsch., 41, 1-106, pls. 1-32. ZIEGLER, W., 1956. Notizbl. hess. Landesamt Boden- forsch., 84, 93-106, pls. 6-7. Addendum While this article was at press, G. Klapper (J. Palaeont. (1969), 43 (1), 1-27) published results of conodont studies from Royal Creek, Yukon, Canada. Several of the Royal Creek forms are identical to specimens from the Lick Hole Limestone. Of special importance is the occurrence of Polygnathus lenzt Klapper (= Poly- gnathus linguiformis dehiscens Philip and Jackson), to which he assigns an early Emsian age. J. Paleont., 12 (5), 411-443, Landesamt January 1969) Explanation of Plates All figures x 40 and specimens registered in the University of New England Palaeontological Collection. Posterior view of 10304/I, locality C22. 2.—Trichonodella symmetrica pinnula Philip. Anterior view of 10304/II, locality C22. Inner view of 10304/3, locality C22. PLATE. I Fic. 1.—Hibbardella perbona (Philip). FIG. Fic. 3.—Neoprioniodus bicurvatus (Branson and Mehl). Fic. 4.—Ozarkodina typica australis Philip and Jackson. Figs. 5, 6.—Ozarkodina typica denckmanni Ziegler. Inner view of 10304/4, locality C22. 8.—Lonchodina n.sp. Philip. Lateral view of 10304/2, locality C22. Inner view of 10303/2, locality C4. Fic. 7.—Plectospathodus alternatus Walliser. Fig. Fic. 9.—Ligonodina salopia Rhodes. Fic. 10.—Lonchodina sp. indet. Fig. 11.—Trnchonodella inconstans Walliser. Lateral view of 10305/I, locality C24. Lateral views of 10307/1-2, locality C54. Posterior view of 10306/2, locality C43. Posterior view of 10304/8, locality C22. PLATE II Fics. 1-6—Polygnathus linguiformis dehiscens Philip and Jackson. 1-4. Oral views of 10307/5,11,6, locality C54, 10306/4, locality C43. 5, 6. Aboral views of 10307/10,9, locality C54. Fics. 7-10.—Spathognathodus steinhornensis optimus Moskalenko. as Oral view of 10306/6, locality C43. 8. Aboral view of 10307/14, locality C54. 9, 10. Lateral views of 10306/7, locality C43, 10303/6, locality C4. Fic. 11.—Spathognathodus primus (Branson and Mehl). Lateral view of 10304/7, locality C22. Fic. 12.—Spathognathodus linearis (Philip). Lateral view of 10302/1, locality C2. hy eta Pay f 1 s f 7 i 100 i t & ee i i F y hed . i i 1 , E \ \ e 5 4 \ — \ { = \ \ ~ o \ \ | = 4 . Se i = == . t a ‘e t \ ‘ ‘ z » \ Ke a ~ q - if 2. os i m f t < are yi \ ' in 1 i — vat i i - rl \ \ cr Jane i ‘ Nes ay 1s ay Sere thas Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 11-20, 1969 Granitic Development and Emplacement in the Tumbarumba-Geehi District, N.S.W. (1) The Fotiated Granites BriAN B. Guy Department of Geology and Geophysics, The University of Sydney, Sydney, N.S.W., 2006 AxBsTRACT—In the Tumbarumba-Geehi district some of the granitic bodies that are in part foliated display a close association in mineralogy, chemistry and field relationships with the surrounding regionally metamorphosed psammopelitic sequence. These folhated rocks—the Cooma-type granites—are characterized by the presence of clusters of biotite, occasional cordierite and patchy zoning in the plagioclases. Chemically the rocks display low Ca contents and a high K: Na ratio, features that are evident in the associated metamorphics. There is a distinct similarity in the chemistry of biotites from the granites, their inclusions, and the high-grade metamorphics. The following sequence of events is envisaged for the formation and emplacement of the Cooma-type granites: (a) high-grade metamorphism of a psammopelitic sequence, segregation of quartzo-feldspathic and biotite-rich sections, and some increase in Ca contents; (6) introduction of sodium, breakdown of micas and the formation of a partial melt, with development of alkali feldspars. Such reactions involve an increase in volume and thus a decrease in specific gravity of the granites with consequent migration and emplacement to higher levels in the crust. Introduction The granitic* rocks of the Tumbarumba- Geehi district, N.S.W. may be classified into several groups on the basis of their textural and mineralogical features and field association with regional metamorphic zones. The aim of this paper is to describe and consider the develop- ment of one of the groups—the Cooma-type granites (Vallance, 1967)—with particular refer- ence to its relationship to the surrounding regional metamorphics. The other granitic rocks present (Khancoban, Mannus Creek and Dargals granites) post-date the regional meta- morphism and will be discussed in a later paper. The distribution of rocks in the Tumbarumba- Geehi district has been noted elsewhere (Guy, 1969). The Cooma-type granites of south-east Australia include the Cooma gneiss (Joplin, 1942), Albury gneiss (Joplin, 1947), Wanta- badgery granite (Vallance, 1953), Mt. Wagra gneiss (Tattam, 1929) as well as the Corryong and Geehi granites of the Tumbarumba-Geehi district. The Corryong granite is part of a large batholith that extends from south-west of Corryong, Victoria to near Adelong, N.S.W. * Unless otherwise stated, the term ‘“‘ granitic’”’, as used in this paper, applies to deep-seated bodies that may be acid-intermediate in composition. Portions of the mass were described by Edwards and Easton (1937) and later by Hall and Lloyd (1950), the latter authors applying the term Maragle Batholith. Vallance (1953) applied the name Green Hills granite to that section of the mass to the north of Tumbarumba. The Geehi granite forms part of a south-easterly extension of the Corryong granite but no investigation con- cerning the continuity of these bodies has been undertaken in connection with this study. The Corryong and Geehi granites are medium grained, remarkably uniform rocks with a high biotite content and free from hornblende; massive in part but generally foliated. This foliation is delineated by a parallelism of bladed micas and elongated xenoliths. The foliation is steeply dipping and has a general trend north- south, and locally parallel to the contacts with the surrounding psammopelitic sequence of Ordovician rocks. Mineralogy and Petrology The normal granitic rocks vary from granits (s.s.) to granodiorite, with the bulk of the rocke being grey adamelites (Table 1). The grain size is even (1-2 mm.) though coarser types with alkali feldspars to 8-10 mm. occur and also some tendency for minerals to be present in clusters, especially biotite. Cell structures with- 12 BRIAN B. GUY in the quartz grains are evident and sometimes assume a typical polygonal arrangement (Plate la). The larger alkali feldspars enclose quartz and plagioclase, suggesting their development later than other phases. Alkali feldspars are optically monoclinic although some cross-hatch twinning occasionally occurs. The triclinicity, TABLE 1 Chemical Analyses, Barth Mesonorms and Modes of Corryong and Geeht Granites 1 2 3 4 SiO, 70-25 69-40 69-70 69-05 110, 0-41 0:49 1-15 0-29 ALO; 13:78 13-58 13°30 15:78 Fe,0, 0-41 0-75 0:27 0-22 FeO 3°04 3°87 3:60 3°62 MnO 0:07 0-11 0:05 0:05 MgO 1-49 2-04 1-66 2°15 CaO 1-80 0-92 1-92 2-50 Na,O 2°41 2-01 2°51 2°49 K,O 4-86 5°14 4-25 3°85 PO; 0-16 0-04 0°15 n.d. H,OF 1-13 1-64 0-94 0:28 H,O- 0-07 0-04 0:09 0°13 Total 99-88 100-03 99-59 100-41 QO 32-96 35°10 34-49 32°54 Or 22-12 21270 17-30 13°33 Ab 22-30 18:70 23°30 22-60 An 6-60 2:75 4-70 11-55 C 2-54 4-22 RIM Ar 3°69 Bi 11-89 15-60 13-84 15-47 Ap 0-35 0-08 0-32 — Ti 0-89 1-05 2-49 0-60 Mt 0:43 0:81 0-30 0:24 Quartz .. 30-0 39-6 39-7 31-4 Plagioclase 31-9 14:5 26-9 26-2 K-feldspar 17-6 23-8 13°2 24-0 Biotite 10:2 13-4 9-6 9-3 Muscovite 5:7 4°5 od oa Cordierite 1-4 1-2 0-2 1-0 Inclusions) BIO PC I 5:4 0:5 ALCCie S7= | sories‘») Garcia ese he oh 2) O-] 0-7 Le3 0:5 ‘a) Included pelitic fragments chlorite and quartz). {b) Apatite, sillimanite, tourmaline, rutile. 1. Spec. No. 21842. Biotite adamellite. G.R.267.0-160.2* (Corryong granite). 2. Spec. No. 21847. Biotite adamellite. G.R.284.6-139.6 (Geehi granite). 3. Spec. No. 21800. Granodiorite. G.R.276.8-165.9 (Corryong granite). 4, Spec. No. 21777. Biotite adamellite. G.R.274.9-174.1 (Corryong granite). Analyst: B. Guy. (mainly muscovite, * Snowy Mountains Authority grid reference (see Guy, 1969). /\, (Goldsmith and Laves, 1954) is in the range 0:25-0:40, and 2Va—80-90°. The K: Na ratio of the alkali feldspars may be estimated utilizing modal and chemical data (including plagioclase and biotite compositions), for specimen 21800 and for the biotite-granite from Vallance (1953, 1960). If assumptions are made as to the compositions of the micas and the accessory minerals, the K : Na ratio may also be estimated for specimens 21805, 21777. All such Or percentages fall in the range 62-68%. The plagioclases are more calcic than those noted by Vallance (1953) in the area north of Tumba- rumba, where most contain 30-35% anorthite molecule. The average composition for plagio- clases from the present area is Ang, _49*, variation being from An,; (at core) to Ang (at margin). The calcic character of these plagioclases is of interest considering the relative low Ca contents of the rocks (Table 1). Most of the plagioclase grains are twinned, with up to four laws being present. A large number of plagioclases contain small areas, somewhat irregular in shape and distribution, that are at a slightly different optical orientation from the main portion of the crystal (Plate 1b). This “patchiness” dis- played by the plagioclase is more evident in varieties where zoning rather than twinning is prominent. The outlines of these small areas is often partly controlled by twinning. Such small patches differ in optical orientation by only a few degrees from the host and do not obey any recognizable twin law. Most plagio- clases have 2Vy from 70-85°, although sodic varieties have 2Va—85-88°. Buiotite is present in clusters with blades being intergrown and occasionally twinned. Generally it is pleo- chroic red-brown, although some dark olive- brown biotites have been recorded. ‘y-ranges from 1-643 to 1-651. One red-brown biotite has been analysed from the present area (Guy, 1964) and its composition is summarized below (No. 1)—specimen 218007, together with a biotite (No. 2) from the area to the north of Tumbarumba (Vallance, 1960). 1. (Ko-75 Nag.os Cag-o4) (Alo-sg Tio-13 Bee es ue Mgo-93 Mng-o1) (Sis-74 Aly-26) O19 (OH) 2 2. {Ko-e4 Nag-o3 Cag-os) “(Alp-ape litt ee Pe: fing Mgo-23 Mng-o1) (Sig-71 Alt-29) O19 (OH). * Compositions of the plagioclases were determined from the extinction angle X’*(010) | [100] measured on a universal stage and referred to the low-temperature determinative curves of Bordet (1963). + Further details of the analysed biotites will be published in a later communication. GRANITIC DEVELOPMENT AND EMPLACEMENT 13 Muscovite is significant as large blades in the Cooma-type granites but cross-cutting other constituents, and is associated with biotite which it may be replacing. The percentage of musco- vite increases with increasing alkali feldspar content. About 2-3°% of the granitic rocks is composed of cordierite or inclusions of pelitic material. The cordierite appears as anhedral grains (1-2 mm.) in part replaced by muscovite. It is homogeneous with 2Va=80°. Patches of sheet silicates, assuming ovoid shapes and 1-3 mm. in size, are ubiquitous in the granitic rocks. They are composed of chlorite, musco- vite with some quartz, biotite and sillimanite. Texturally these micaceous aggregates appear as inclusions in the host granite. They may in part represent pseudomorphs after cordierite. Accessory minerals in the granitic rocks are opaque oxides, tourmaline, apatite, sillimanite, zircon, rutile, monazite, calcite and epidote. Marginal phases of the granites have high tourmaline and muscovite contents, with biotite being replaced by these two minerals. Throughout these granites shear zones are numerous, varying from 5 cm. to a metre in width, though Vallance (1953) and Beavis (1961) describe crush bands several hundred metres wide in similar granitic rocks. Shearing effects produce some reduction in grain size with assemblages such as “ quartz-feldspar-chlorite- muscovite ’ being produced. Aplites, pegmatites and graphic granites form significant occurrences in the Cooma-type granites. Aplites occur as_ small _ veins occupying joints. Quartz, optically mono- clinic alkali feldspar and oligoclase are the dominant phases, being in approximately equal quantities. Dark-green biotite, muscovite, tourmaline, apatite and opaque oxides are accessories. Tourmaline-rich bands characterize many of the aplitic veins. Pegmatites are mineralogically similar to the aplites, but oligoclase is subordinate. Tourmaline in the pegmatites has a basal parting (up to 0-5 mm. wide) filled with quartz and iron oxides. Associated with the aplitic and pegmatitic phases are dark, fine grained dykes consisting essentially of chlorite and tourmaline with some quartz and opaques. These rocks are prevalent in the area south of Tumbarumba and are associated with shear bands in the granite and quartz-sulphide veins. Although the ori- ginal composition has presumably been exten- sively modified, they may represent basic dykes that have been sheared and altered by hydro- thermal activity. Large inclusions (>5 cm.) are prominent throughout the Corryong and Geehi granites, being of psammitic to pelitic character and mineralogically and texturally similar to the high-grade regional metamorphics of the district (Guy, 1969). Some quartz nodules (5-10 cm. in size) are also common throughout the Cooma- type granites. Most inclusions differ from the country rocks in that plagioclase is significant in the former rock type as porphyroblasts of An3, composition. The plagioclase is euhedrally zoned with cores of An;y, and 2Vy=80-90° ; some “patchiness’’, as described for plagio- clases of the granitic rocks, is evident. Biotite is present throughout all the inclusions, and is frequently concentrated around the margins of the larger sandier types. Structural formulae for some biotites are noted below. Nos. 1 and 2 are red-brown types (y=1:645) common to most inclusions, while Nos. 3 and 4 are yellow- brown varieties (y=1-625) noted in some of the sandier rocks. No. 1 is from Vallance (1860) and the remainder from Guy (1964). Modal analyses of the host inclusions are noted in Table 2. 1. (Ko-gg Nao-rg Cao-o3) (Alo-37 To-az Fe 5, Fe2+ Mno-o2 M&y-04) (Siaegs Ali-s5) O10 1-11 (OH)» 2. (opecs 21798). (iKacg Nang Capa) meee Tig-ze Feg+, Fe?4, Mmo-o. M8o-97) (Sie-67 Alj-33) O19 (OH)e 3. (Spec. 21807) (Ko-s, Nap-3¢ Cao-00) (Alp-so Tig-os Fegt Fee, Mno-oo M8i-27) (Sle-go Alj-11) Or (OH)» 4, (Spec. 21787) ~(Ko-79 Nap-93 ©ap:93) (Alp.32 Tig.os Fest, Fett, Mion Mg, .55) Alj-29) O19 (OH)2 The Mg-rich micas (Nos. 3 and 4) have only been observed or suspected in these inclusions, whereas they appear to be lacking in the granite and regional metamorphics. The lower grade metamorphics may prove to contain some ex- ceptions (Guy, 1969, Table 1). The silica content is appreciably higher for these Mg-rich varieties. Cordierite is abundant in the pelitic inclusions as ragged crystals with a distortion index, A, (Miyashiro, 1957) of 9-19-+0-03 and B=1-553-+ 0-003, indicating (ca.) 25°% Fe substitution for Mg. Sillimanite is present in the fibrolite form, although numerous needle-like crystals are associated with the matted fibrolite. Musco- vites in the inclusions vary from large blades (2-3 mm. long), cross-cutting other minerals, (Sig. g9 14 BRIAN; B GUY to sericitic varieties which replace nearly all the phases except quartz. Chlorite, in part after cordierite, may be associated with the fine matted micas. TABLE 2 Chemical Analyses, Barth Mesonorms and Modes for Inclusions in Cooma Type Granites 1 v4 3 4 5 6 SiO, 66:27 |57-70 |54-86 [54-22 [45-73 |44-87 TIO>5 0-88 | 1-80 | 1-18 | 1-78 | 0-13 | 2-50 Al,O, 13°85 |14-17 |18-32 |21-O01 |27-83 (28-42 He,@; 0:27 | 0-28 | 2-01 | 1-79 | 1-05 | 0-26 FeO 3°55 | 7-36 | 8°01 | 5-61 | 6-80 | 7-97 MnO 0:06 | 0°13 | 0-14 | 0-14 | 0:06 | 0-26 MgO 5:50 | 7-23 | 4-16 | 2-43 | 4-95 | 4-45 CaO 2-54 | 3:35 | 1°95 | 0-49 | 0-20 | 1-49 Na,O 2°57 | 0-73 | 2-46) 127571 0-27 | 2-02 K,O 3°01 (4° 5) a+ 22 4 Fe4d eS Tel 3-7 PO. 0-01 | 0°12 — 0:31, ned 0-12 HO 0:90 | 1:90 | 1°30 | 2:46 | 4:00 | 3-40 HeO- 0:18 | 0:23 | 0-22 | 0-36 | 0°40 | 0-23 18 a — — — — 0:06 — Less O for Ea yy ae — — — — 0:03 oe Total | 99-59 | 99-51 | 99-83 | 99-76 | 99-62 | 99-70 O . 13838°05 (29-61 [16-46 |15-04 {12-14 |16-80 Or 0°62 |. 0°55 [12218 133: 107 /29-82..| W225 Ab 23°45 | 6-80 |22-60 {16-35 | 2-50 {18-75 An 9-60 | 9:90 | 5-70 0-60 — C 3°22 | 5°22 | 7-37 111-48 |20°83 (23-81 Bi 27-89 {43°44 |30-99 |19-92 |82-69 |34-32 Ap 0:03 | 0:27 — 0:67 — 0:27 Ti 1-86 | 3-90 | 2-52 | 0°33 | 0-27 | 4-08 Mt 0-28 | 0-30 | 2-16 | 1-95 | 1°14 | 0:28 Rt — — — 1-18 —— 0:44 Quartz 34:9 | 28-5 | 22-2 * * 0-2 Alara la feldspar 1:3 — 1-6 = * 0:3 Plagioclase} 32-8 | 22-3 | 24-4 = * 15-7 Biotite . 31:0 | 47-9 | 42-3 * = 20:6 Muscovite — 1:1 8-4 - * 20:7 Cordierite — — — + * 31-5 Sillimanite}| — — | (Pre- * * 3°1 sent) Acces- sories —_ 0-1) 1-0 = * 2-0 lL. Spec. No: 21807: G.R. 278.5-175.4. 2; spec. No. 217872 G.R. 274.1-155.8. 3. Biotite-rich patch in granodiorite. 4 Biotite-quartz-plagioclase rock. Biotite - rich psammopelite. Tenandra Trig. Vallance (1953). . Micaceous xenolith in granite, Mt. Wagra. (1929). 5. Pinitized cordierite Tattam (1929). 6. Spec. No. 21798. G.R. 277.2-165.2. Analysts: 1, 2, 6—B. Guy. 4, 5—C. M. Tattam. * Data not available. Tattam inclusion, Kerungah Gap. Cordierite-biotite-sillimanite rock. 3—T. G. Vallance. Chemical Data (1) Granitic Rocks. Four new analyses of granitic rocks from the Cooma-type granites are presented in Table 1. The granites are characterized by high Al,O, contents, low CaO and a K,O:Na,O ratio higher than unity. Chemical data have been summarized in Fig. 1. A K F Fic. 1—AKF diagram for the Cooma-type granites. Analytical data from Table 1, this paper (Nos. 1, 2, 3, 4) ; Tattam, 1929 (T); Edwards and Easton, 1937 (E) ; Joplin, 1942 and 1947 (J); Vallance, 1953 (V). Many of the rocks contain less than 80% norma- tive AB+Or-+C and thus would not be classified by Tuttle and Bowen (1958) as granites* (s.s.). (11) Inclusions. Three new analyses are listed for inclusions from the Cooma-type granites in Table 2, together with analyses from Vallance (1953) and Tattam (1929). An examination of modes and the analytical data for the inclusions reveals a close correspondence indicating that the phases have compositions close to the ideal normative minerals calculated. Utilizing the biotite analysis for specimen 21798, together with the modal data, the Mg: Mg+Fe+Mn value for the cordierite of this specimen may be estimated at (ca.) 0:6. The associated biotite has a value of 0-44. The Mg: Mg-+Fe+Mn ratio averages 0:40 both for the Cooma-type granites in south-east Australia and the pelitic rocks in the associated Ordovician sequence, while the associated psam- mopelites and the psammites average 0-33. Inclusions of the latter rock type (Table 2) have an Mg : Mg+Fe+Mn ratio of 0-67. * Tuttle and Bowen utilized C.I.P.W. norms, whereas Barth mesonorms have been used in Table 1. GRANITIC DEVELOPMENT AND EMPLACEMENT 15 TABLE 3 Antons Associated with Cations* in Metasediments, Inclusions and Granites (a) Psammites and Psammopelites ee ee (?) Unmetamor- Knotted phosed or Low- Biotite Schist grade Zone Zone Zone 186-55 182-17 188-06 — 185-04 = Average : 186-55 183-61 188-06 (b) Pelites 162-13 175-18 172-39 173-58 175-74 172-45 173-67 177-13 172-77 175-52 — 173-44 178-65 aa 174-80 179-22 = 175-41 185-14 = 181-81 185-67 — 183-10 Average : 177-95 176-02 174-65 High-grade Inclusions Granites Zone 174-46 169-53 178-01 167-80 170-04 181-39 — 170-94 170-95 177-95 168-67 172-57 173-45 173-76 173-85 167-13 163-96 174-75 167-22 167-07 175-36 167-67 167-86 169-41 167-89 175-41 170-19 — 175-54 171-64 — ; no 172-08 175-78 £2 = 179-89 169-29 166-70 173-92 * Cations summed to 100.00. See Figs. 1 and 2 for references to analytical data on granites, and Guy (1969) for data on metasediments. Anions associated with 100 cations in the Cooma-type granites, their inclusions and the Ordovician metasediments are listed in Table 3. The metasediments show a general trend of decrease in the number of associated anions from low grade through to the inclusions with an increase of (ca.) 4°% from the inclusions to the granites. Figures 1 and 2 summarize some of the chemical features of the metasediments, the inclusions and the Cooma-type granites. Origin of the Granitic Rocks The spatial distribution of the Cooma-type granites relative to the regional metamorphic zonal sequence and the high amount of included material in the granite suggest a close association between granite and surrounding country rock material. Mineralogically this is evident in that cordierite may be present in the granitic rocks and there is a similarity in the optical and chemical properties of the biotites in the meta- sediments and granite. The metasediments are _ characterized by a restricted chemical nature _ (Guy, 1969) being rich in alumina and potash, _ low in lime and soda, while the Cooma-type _ granites display a similar nature in that alumina _and potash contents are high, with lime being _ low but slightly more significant than in the metasediments. Soda, however, is present in appreciable proportions in the granites. Val- lance (1953) estimated the country rocks in the Wantabadgery area have an average composi- tion of a psammopelite, with the ratio pelite: Q Ne Fic. 2—Q-FI-Px diagram showing the general distribu- tion of Cooma-type granites (G), their inclusions (I,, psammopelites ; I,, pelites) and Ordovician meta- sediments (M,, psammopelites ; M,, pelites). See Guy (1969) for references to the analytical data of the meta- sediments. 16 BRIAN B. GUY psammopelite : psammites being 20 : 60 : 20. This approximation appears to be a satisfactory estimate of the relative proportions of such rocks in the Tumbarumba-Geehi district. Vallance observed that such an average ‘‘ psammopelite ”’ was chemically similar to the granite except for a deficiency in the Na and Ca in the former rock, and suggested that granites were derived largely from materials of the sedimentary pile. Joplin (1962) has postulated the idea of an oligoclase magma being added to the “ psam- mopelitic ’’ sequence to produce the Cooma-type granites. It is doubtful if such a magma is really necessary to form such granites; indeed Kolbe and Taylor (1966) have argued against this mainly on the basis of K : Rb ratios in these rocks. These latter authors, together with Pidgeon and Compston (1965), have suggested derivation of the Cooma-type granites entirely from the surrounding metasedimentary sequence. Joplin (1962) does not adhere to the idea of melting 7m situ alone because of the steep thermal gradients as indicated by the metamorphic zones surrounding the granite masses. Field relation- ships between granitic and metamorphic rocks in the Wantabadgery area led Vallance (1953) to suggest that the granites there probably developed at some lower level and were later emplaced at a higher level in the crust. Simi- lar relations exist in the Tumbarumba-Geehi district. Previous investigations of the Cooma-type granites have demonstrated that such rocks are derived primarily from metasediments similar to those exposed in Ordovician areas of south- east Australia. As yet there is little detailed information regarding the mineralogical processes involved in the transformation to such granites, or on the physical state of the metasediments during transformation. Before considering these aspects several important features of the Cooma- type granites should be emphasized. The granites are broadly homogeneous in that textural and mineralogical features are reason- ably constant throughout the various bodies. However, on the scale of an outcrop (several square metres), such rocks are characteristically heterogeneous with numerous inclusions (>2 cms.) occupying up to 10-159% of an exposure. Smaller inclusions (<2 cms.), not always readily discernible macroscopically, may occupy 5% (see Table 1) of such granites. Clustering of mineral phases is particularly evident with the micas but also present in quartzo-feldspathic sections. Thus a granite analysis as quoted in the text and figures repre- sents but an average of these features, while the bulk chemistry of, say, the Corryong granite cannot possibly be represented by “ granite ”’ analyses alone. The predominance of included country rock material in the granites, the similarity in mineral- ogical features to both the metasediments and the granitic rocks, and the textural features outlined above suggest that the inclusions are at an intermediate stage in the transformation to granitic material rather than a “ by-product ” of granitic development. Most of the inclusions contain mainly quartz and biotite with minor plagioclase feldspar as well as cordierite, silli- manite, etc. The inclusions are mica-rich and from the analytical data (see Fig. 2) contain markedly lower quantities of silica than the metasediments. Thus transformation from metasediment to inclusion may involve a segregation into a quartz or quartzo-feldspathic section and a mica-rich section. The mica-rich sections are obvious on a microscopic to a macroscopic scale. The lighter coloured por- tions are not immediately apparent in the vicinity of biotite-rich areas. The quartzo-feldspathic components may have been able to diffuse into their surroundings or migrate some distance— perhaps to contribute to the aplitic, pegmatitic and graphic granite phases that are common throughout the Cooma-type granites. The pre- dominance of quartz over feldspars in the metasediments could have resulted in the segregation of quartz-rich areas. Quartz nodules throughout the granite may be representatives of this segregation. The process of segregation is conceivably a continuation of the regional metamorphic processes with diffusion being a principal agent by which rearrangement of material takes place. Most of the inclusions contain small amounts of plagioclase. This plagioclase is somewhat similar to that observed in the granitic rocks and is reasonably calcic (cores of An;, have been recorded). The feld- — spars are discussed in more detail below (see p. 17). From an examination of Table 3, it is evident that the number of anions associated — with 100 cations decreases with increasing grade | of metamorphism. This effectively means that with increase in grade (until the stage of inclu- | sions) there is a decrease in the overall volume | of the rocks (~7°%) and a corresponding increase _ in density. | Although there is a large variation in the | degree of disintegration of the inclusions, trans- | formation of inclusions to granite is very diffi- | cult to interpret. One of the most interesting — features of the granitic rocks is that whereas © bulk calcium contents are low (as are those of © GRANITIC DEVELOPMENT AND EMPLACEMENT 17 the original metasediments) calcic cores are not uncommon in the granite plagioclases. Such cores are unlikely to from unless temperature conditions were sufficiently elevated or calcium was locally concentrated relative to sodium. It is unlikely that P—T conditions in Tumba- rumba-Geehi district were elevated enough for large scale melting to occur, and it is thus con- ceivable that in the early stages of transforma- tion to granite there has been local concentration of calcium. The rather patchy zoning of the plagioclases may reflect a later introduction of sodium into the system of the granitic rocks. Certainly Na,O is deficient in the metasediments compared with the granites. Vance (1965) favours mag- matic resorption due to the release of confining pressure associated with emplacement as a major cause of patchy zoning in plagioclase. This factor cannot be overlooked here although there are no criteria directly supporting such an ex- planation. Subhedral or euhedral crystals do not display any obvious embayments while many of the patchy areas terminate along twin boundaries (see Plate 1) that are essentially low energy boundaries and should not be a general limitation in resorption. It is noteworthy that the Cooma-type granites do not display the degree of oscillatory or sharp normal zoning that is evident in the Khancoban, Mannus Creek and Dargals granites (Guy, 1964). These later bodies are interpreted as having migrated rather further from their position of origin than the Cooma-type granites, and hence are more likely to contain mineralogical features com- patible with a history of such emplacement. It is considered that the features display by the plagioclases in the Cooma-type granites are a direct result of local concentration of calcium followed by an influx of sodium into the granitic rocks. Such an influx of sodium may have taken place by diffusion in the solid state, or through the introduction of melt or solution. Either process would be aided by an increase in temperature conditions. The physical state of the granitic rocks during the introduction of sodium may conceivably have been that of a partial melt. This aspect will be discussed in more detail below (p. 19). The nature of the alkali feldspars is of interest in the granitic rocks. Marmo (1967) contends that potash feldspars of most synkinematic granites are highly triclinic microcline, although potash feldspars that form porphyroblasts not uncommonly have lower triclinicities. Such feldspars are younger than other constituents in B these rocks. He suggests that where there has been reasonably rapid introduction of potassium with little time for Al-Si ordering in the develop- ing feldspars, orthoclase may be formed, whereas if the introduction rate is slow, ordering results and microcline will develop. The optical pro- perties of the alkali feldspars in the Cooma-type granites of the present area indicate that the alkali feldspars are not highly triclinic and form ‘“porphyroblasts’’” and thus they may have formed in a manner envisaged by Marmo. However, according to the scheme of Laves and Viswanathan (1967), the feldspars with low A values and high 2V may consist of domains with a high degree of order, i.e. the alkali feldspar are submicroscopically twinned. Thus A _ values for this suite may not be as low as indicated. The reason for the paucity of twinning in such feldspars is difficult to interpret and growth may be similar to that suggested by Marmo, i.e. growth is rapid so that the phase grew essentially as a monoclinic phase and not as “ microcline ”’ The influence of post crystallization deformation cannot be neglected here. Microcline with higher obliquity than orthoclase should twin less readily, however, this does not appear to be the case for most natural occurrences. Possibly the optically monoclinic feldspars of these granites have a high triclinicity and do not display a great deal of obvious twinning due to a rapid fall in temperature conditions after their formation, and the lack of any major deformation. The K : Na ratio of the alkali feldspars in the Cooma-type granites is somewhat lower than that observed in other granitic suites of the Tumbarumba-Geehi district. This may be re- lated to high degree of unmixing in the latter rock types and perhaps the Cooma-type granite alkali feldspars have developed when there was a relatively greater availability of sodium. Marmo (1967) considers that many of the synkinematic granites have experienced addition of K and to a minor degree Na. Chemical data from the present investigation is more suggestive of introduction of sodium, as potassium contents of the granitic rocks (considering the composition of the inclusions as well) does not appear to differ markedly from that of the metasediments. Textural evidence indicates that the alkali feld- spars and muscovite have formed somewhat later than other constituents, however, it is considered that such potassium is derived locally from the disintegration of muscovite and biotite in the inclusions, perhaps associated with a rise in temperature conditions. Stability of micas until late in the transformation process may be 18 responsible for survival (or perhaps production— see below) of cordierite in some of the granitic rocks. It may be significant that the Mg : Mg-+Fe+ Mn ratio for the Cooma-type granites is slightly greater than that of an average psammopelitic metasediment (p.8). This may imply that there has been a slight enrichment in Mg relative to Fe in the granitic rocks. The high value for this ratio in some of the analysed psammopelitic inclusions may be the result of such enrichment. The transformation of inclusions to granitic material would require some addition of silica (see Fig. 2). This would be consistent with the expected reaction of micas (Si1:O ratio ~1:3-3) transforming to feldspars (Si: O ratio ~1:2-7). Winkler (1967) suggests a reac- tion such as 2 biotite+6 sillimanite+9 quartz—-2 K- feldspar component+3 cordierite+2 H,O. This reaction may in part be responsible for the paucity of quartz-rich or quartzo-feldspathic segregations immediately adjacent to mica segregations. The average bulk composition of the granite and biotite-rich inclusions would be markedly lower in SiO, than an average psammopelite. The transformation of inclusion to homogeneous granite would involve an increase in the number of anions associated with 100 cations (see Table 3) and hence an increase in volume or decrease in density. This may have influenced migration of granitic rocks to higher Q = —_—-O— — — — (a) Ab Or Fic. 3 Projections of sections through the system Q-Ab-An-Or-H,O at Py,0= 2,000 bars. BRIAN B. GUY levels in the crust. The granites are in places surrounded by lower grade sections of the high grade zone or upper knotted schist zone rocks (Guy, 1969)—apart from where faulting has been operative. Such metasediments would have a similar specific gravity to that of the granites. The bulk composition of the granitic rocks is such that few samples contain more than 80% Q+Or-+Ab or fall in the low-temperature through of Tuttle and Bowen (1958). The normative ratio of Q: Or: Ab is approximately — 45 : 30:25, although biotite clusters frequently have granular quartz associated with them, thus the Q content of portions of the granites capable of melting may be less than that indicated by the above ratio. Von Platen (1965) has suggested that the Ab: An ratio is an important factor on the “minimum melting point’ (Winkler, 1967) in the system Q-Ab-An—Or at Pyso=2000 bars. With increase in Ab: An ratio the “minimum melting temperature ”’ decreases and is relocated towards the Ab corner, restricting the plagioclase field. A plot of some Cooma-type granites is noted in Fig. 3 with reference to this system. These analyses are presented on two Q—Ab-Or projections to illustrate the influence of Ab: An ratio on their crystallization history. Those rocks with low Ab: An ratio (<3-0) generally lie on the Ab side of the cotectic curve. Thus if such (or similar) rocks were melting plagioclase would be the last phase (neglecting biotite, etc.) to go into the melt. This may imply that any Q (b) Ab Or melt ’’ composition are indicated (©) and some cotectic curves for various Ab : An ratios. (After Von Platen, 1965.) (a) Plot of Cooma-type granites (x) with Ab: An<3-0. The boundary between the plagioclase and K-feldspar fields (for Ab: An=1-8) is indicated. (b) Plot of Cooma-type granites (x) with Ab: An>3-0. Figures against (x) symbols refer to the Ab: An ratio of the granites. : Points of ‘‘ minimum { { | | | | GRANITIC DEVELOPMENT AND EMPLACEMENT 19 quartz-alkali feldspar-rich or quartz-rich segre- gations that may have developed in such granitic rocks through a segreation process, would be particularly susceptible to melt conditions. If introduction of sodium followed some melting of rock types represented by Fig. 3a, there would be a marked change in the ratio of Ab: An (as the An contents are generally not large) as well as depressing the “ minimum melting temperature ’’. The “ minimum melt ” -and the cotectic line would be relocated towards the Ab corner. As such sodium introduction would not greatly change the amount of Ab relative to Or and Q, the plot of the granitic rocks on the diagram Q-—Ab-—Or would not be significantly altered. If associated with sodium introduction, there was breakdown of micas (see p. 18) and perhaps some incorporation of quartz-rich segregations (cf. Fig. 2), the bulk composition of the granitic phases would be relocated away from the Ab corner. Thus the distribution of granitic rocks noted in Fig. 3b—1.e. those with high Ab: An ratio—may be explained by such a sequence of events. It is interesting that in the latter case those rocks with high Ab: An ratio, would lie on the Q side of the cotectic and thus quartz would be the last phase to melt. Thus fluctua- tion in temperature, pressure, breakdown of biotites, or introduction of Na would have a marked influence of the phase(s) in equilibrium with the melt. The patchy zoning of the plagioclases may be a direct result of such a crystallization history. Some recent investigations by Weill and Kudo (1968) have thrown some doubt on the work of Von Platen. The former authors suggest that the Q—Or-Ab system does not have a unique melting point or a unique composition of initial melt. This does not detract from the suggestion by Winkler (1967) that for any Ab: An ratio there is still a minimum melting point for the system. Some doubt exists as to whether the minimum melting points determined by Von Platen is the absolute minimum in the system Q-Ab-—An-Or for a fixed Ab: An ratio. Weill and Kudo’s suggestion that there is a unique melting point for a given Ab : Or ratio may not be particularly significant for the Cooma-type granites con- sidering that the development of such rocks is related to breakdown of the micas. If it is assumed that Von Platen’s experimental study does suggest a trend for minimum melt composi- tion with variation in Ab: An ratio, a feasible theory may be proposed for the development of the Cooma-type granites. The sequence of events envisaged in the formation of these granites may be summarized. as: 1. Very high grade metamorphism of a sequence of rocks with a compositional range close to that of a psammopelite. The meta- morphism involves a decrease in volume with increase in grade. The principal phases would be quartz, micas (mainly biotite) and minor, but rather calcic plagioclase. Calcium and magnesium may have been locally concentrated at this stage. Some segregation of constituents may have taken place producing quartz-rich or quartzo-feldspathic-rich, and mica-rich sections. Diffusion would presumably have been the main process involved in migration of material. Melt is considered not to have been of much signi- ficance at this stage. 2. Introduction of sodium, possibly by local concentration from the metasediments, but more likely by diffusion from lower levels in the crust. Such diffusion of sodium would be favoured by elevated temperatures. Both con- trols (elevated temperature and Na introduc- tion) would be conducive to the production of a partial melt and migration of the cotectic line of the system Q-—Ab-—An—Or-—H,O towards the Ab corner. Breakdown of micas, also com- patible with increase in temperature would favour a change in the phase co-existing with the melt. Such conditions are considered to have been a significant factor in producing the patchy zoning in the plagioclase and the produc- tion of alkali feldspars in granitic rocks. The reactions involved in this transformation to granite may have resulted in an increase in volume (cf. Table 3) and a decrease in density. This may have been a factor in the migration of Cooma-type granites to higher levels in the crust. It is possible that these rocks have been annealed after emplacement with a significant modification of their textures. The cell struc- tures noted in the quartz grains and some undulatory character of the feldspars may have developed through such a process as annealing. Pidgeon and Compston (1965) have suggested an age of 415+12 m.y. for the Cooma granite and the surrounding high grade metamorphics at Cooma. More distant greenschist facies rocks are reports to have an age of 460-+11 m.y. These authors indicate there is no evidence to suggest any metamorphism later than that developed in the high grade zone and propose that the Cooma granite is locally derived from rocks in the high grade zone. In the Khan- coban area (Guy, 1969) there is evidence that the regional metamorphism is multiple in 20 BRIAN B. GUY character and that this is discernible only in the higher grade metamorphics. Pidgeon and Compston have not discussed fully the signifi- cance of similar ages obtained for the Cooma granite and a section of the Murrumbidgee batholith. Acknowledgements I wish to thank Associate Professor T. G. Vallance for advice and criticism both during this study and in the preparation of the manu- script, and Professor C. E. Marshall in whose Department this work was carried out. References Beavis, F. C., 1961. Mylonites of the Upper Kiewa Valley. Proc. Roy. Soc. Vict., 74, 55-68. 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N.S.W., 67, 156-196. Joprin, G. A., 1947. Petrological Studies in the Ordovician of N.S.W. IV. The Northern Exten- sion of the North-east Victoria Metamorphic Complex. Proc. Linn. Soc. N.S.W., 82, 87-124. and Mineralogical Geology of the Unpublished Ph.D. (Received 8 July 1968) Jopiin, G. A., 1962. An Apparent Magmatic Cycle in the Tasman Geosyncline. J. geol. Soc. Aust., 9, 51-69. KoLBeE, P., AND TAYLorR, S. R., 1966. Geochemical Investigations of the Snowy Mountains Area, New South Wales. J. geol. Soc. Aust., 13, 1-26. LavEs, F., AND VISWANATHAN, K., 1967. Relation between Optic Axial Angle and Triclinicity of Potash Feldspars, and Their Significance for the Definition of “‘ Stable’’ and “ Unstable ’’ States of Alkali Feldspars. Schweiz. Min. Petr. Mitt., 47, 147-162. Marmo, V., 1967. On Granites: A Revised Study. Bull. Comm. géol. Finl., 227, 1-83. MIyaAsHIRO, A., 1957. Cordierite-Indialite Relations. Am. J. Sci., 255, 43-62. PipcGEon, R. T., AND Compston, W., 1965. The Age and Origin of the Cooma Granite and Its Associated Metamorphic Zones, New South Wales. /. Petrology, 6, 193-222. TattamM, C. M., 1929. The Metamorphic Rocks of North-eastern Victoria. Bull. geol. Surv. Vict., TUTTLE, O. F., AND BowEn, N. L., 1958. Origin of Granite in the Light of Experimental Studies in the System NaAISi,0,-KAISi,0,-SiO,-H,O. Geol. Soc. Amer. Mem., 74. VALLANCE, T. G., 1953. Studies in the Metamorphic and Plutonic Geology of the Wantabadgery- Adelong-Tumbarumba District, N.S.W. III. The Granitic Rocks. Proc. Linn. Soc. N.S.W., 78, 197-220. VALLANCE, T. G., 1960. Notes on Metamorphic and Plutonic Rocks and Their Biotites from the Wantabadgery-Adelong-Tumbarumba District, N.S.W. Pyroc. Linn. Soc. N.S.W., 85, 94-104. VALLANCE, T. G., 1967. Palaeozoic Low-pressure Regional Metamorphism in South-eastern Australia. Meddr. dansk. geol. Foren., 17, 494-503. VANCE, J. A., 1965. Zoning in Igneous Plagioclases : Patchy Zoning. J. Geol., 73, 636-651. Von PLATEN, H., 1965. Experimental Anatexis and Genesis of Migmatites. In Controls of Meta-— morphism, ed. by Pitcher and Flinn. Oliver & Boyd, London. WELLL, D. F., and Kubo, A. H., 1968. Initial Melting in Alkali Feldspar-Plagioclase-Quartz Systems. Geol. Mag., 105, 325-337. WINKLER, H.G. F., 1967. Petrogenesis of Metamorphic Rocks. Springer-Verlag, Berlin. JOURNAL ROYAL SOCIETY N.S.W. GUY PLATES la-Ib PLATE 1 (a) Cell structure in a quartz grain from the Corryong Granite (spec. 21809). Note the polygonal arrangement of the small domains. Crossed nicols, x 120. PLATE 1 (b) Section of a plagioclase grain displaying patchy zoning, from the Corryong Granite (spec. 21842). This zoning is evident only near the extinction positions. Crossed nicols, x 45. Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 21-39, 1969 The Nature and Occurrence of Heavy Minerals in Three Coastal Areas of New South Wales Jia EIATES® ABsTRACT—A detailed mineralogical study has been undertaken in an attempt to determine the sources of heavy minerals in three areas of New South Wales. The areas studied are Twofold Bay and neighbouring South Coast districts between Pambula and Disaster Bay, Broken Bay near Sydney, and the Mid-North Coast between Port Macquarie and Grassy Head. The percentage variations of different minerals in both Pleistocene and Holocene sediments have been evaluated. Diagnostic heavy minerals have been traced in some barrier and dune sands, and it is believed that these were transported shorewards during marine transgressions accompanying interglacial periods, and reworked locally by longshore drifting. Most of the minerals in the unconsolidated deposits on the east Australian coast can be described as polygenetic because they have been derived from various sources, and their origin is very complex in relation to both time and place. Introduction (a) The Nature of the Problem: The barriers? and dunes on the New South Wales coast are composed of sediments that were reworked during Pleistocene fluctuations of sea-level and during the post-glacial or Holocene marine transgression. Such deposits can there- fore be described as polygenetic since they have been derived from various sources and their origin is very complex in relation to both time and place. The writer has analyzed Pleistocene and Holocene sediments in an attempt to determine the sources of the heavy minerals in three coastal areas of New South Wales. The areas, which differ geologically and _ physio- graphically, are Twofold Bay and _ neigh- bouring South Coast districts between Pambula and Disaster Bay (Figure 1), Broken Bay near Sydney (Figure 2), and the Mid-North Coast between Port Macquarie and Grassy Head (Figure 3). The origin and distribution of heavy mineral beach sands in New South Wales and south- eastern Queensland have been mentioned briefly ‘Senior Lecturer, Department of Geology and Geography, University of London, Goldsmiths’ College, New Cross, S.E.14. * The term barrier applies to littoral sand accumula- tions—either beaches, spits or islands—that stand permanently above high-tide level and enclose lagoons or shallow bays. Barriers are usually characterized by multiple beach ridges, but a few are comprised of a single ridge. A few beach ridge systems, for example, the Umina-Woy Woy system in Broken Bay, are not separated from a bedrock hinterland by large coastal lagoons. in technical reports by Gardner (1955), Whit- worth (1956) and Connah (1962). Jones (1946) and Beasley (1948, 1950) have discussed the concentration of heavy minerals in_ beach deposits. Culey (1933, 1939) studied the heavy mineral assemblages of the Narrabeen and Hawkesbury Sandstones. However, no detailed investigations have been made to determine the relationship between heavy mineral concentra- tion and longshore drifting, aeolian activity and the shoreward movement of material from the sea floor during marine transgressions. (0) The Phystography and Geology of the Areas: Dual barrier systems, composed entirely of quartzose sand and separated by swamps and lagoons, have been mapped on several sectors of the New South Wales coast. These have been termed Inner (Pleistocene) and Outer (Recent) Barriers by Langford-Smith and Thom (1969). The Holocene (Recent) barriers developed across the mouths of drowned river valleys to enclose estuarine lagoons partly or completely from the sea after 7000 B.P. (before the present), at a time when the rate of the post-glacial or Holocene rise of sea level slowed down appreci- ably (Hails, 1968). The barrier systems of the Central and South Coast of New South Wales are not as clearly represented by Pleistocene and Holocene components as those on the Mid- North Coast which border large fluvial-deltaic 3 The terms Outer (Recent) Barrier and Inner (Pleistocene) Barrier will be used in the same context as originally defined by Langford-Smith and Thom (1969). 22 plains. This is because former broad protected bays of the North Coast, and an abundant supply of sand from large rivers, favoured the develop- ment of wide barriers, while the more rugged embayments and lack of large rivers on the Central and South Coast did not. The limited extent to which the estuarine lagoons on the South Coast have been filled by fluvial deposits also reflects the size, discharge and sediment yield characteristics of the river catchments (Bird, 1967). Twofold Bay (Figure 1) and adjacent areas are composed of strongly folded and faulted Devonian strata, with Ordovician metamorphic Crm) “QUARANTINE BAY Traverses along which \\ boreholes were sunk WALA Lp - A——AI = Sampling sites | <=> Bayhead beaches and barriers CLP Sandflats ww Swamp | RAs consists of a series of abandoned beach ridges with intervening swales and is backed by degraded sea cliffs. Eden barrier spit impounds Curalo Lake which occupies the valleys of Bellbird Creek and adjacent coastal streams. Whale Beach barrier encloses the Towambah (Kiah) estuary and north of Twofold Bay, Pambula barrier spit partly encloses Merimbula Lake. Broken Bay (Figure 2) is part of the dendritic drowned valley of the Hawkesbury River, and is dominated by vertical cliffs cut in resistant, almost horizontally-bedded, Hawkesbury and Narrabeen sandstones of Triassic age. Lentic- 3. Mid-North Coast 2. Broken Bay 1. Twofold Bay and South Coast Areas. TWOFOLD BAY areas in New South Wales. rocks and Tertiary basalts (Brown, 1930, 1933 ; Steiner, 1966). The sedimentary rocks around Twofold Bay are of variable composition, and are associated with rhyolites, basalts and dolerites. Unconsolidated sands and gravels of varying thickness which directly overlie the Devonian rocks have been designated Tertiary (Hall, 1957). Twofold Bay, one of the largest embayments on the South Coast, is actually a succession of smaller bays, with bayhead beaches, which are separated by headlands and small promontories. The Boyd Town barrier system is the largest of its kind inside the bay, and is situated between the Nullica River and Boyd Town Creek. It ular layers of shale are interbedded with the sandstones which are characterized by major systems of vertical joints (David, ed. W. R. Browne, 1950). Tertiary dykes and sills have been reported in a few coastal sections. Patonga Beach is a sand barrier which almost completely | encloses the mouth of Patonga Creek in Brisk Bay, whilst Pearl Beach barrier originally developed across the mouth of a small embay- | ment. The Umina-Woy Woy barrier is the largest depositional feature in Broken Bay. It con- sists of a series of abandoned beach ridges aligned | parallel to the shoreline. There is some evidence to suggest that this barrier may be composed © > > ari drowned — NATURE AND OCCURRENCE OF HEAVY MINERALS 23 of Pleistocene as well as Holocene sediments (Hails, 1969), in contrast to Pearl Beach and Patonga Beach which are Holocene barriers. The Mid-North Coast (Figure 3), is character- ized by zeta-curved or arcuate bays which are flanked by resistant bedrock headlands. Some of the headlands are mantled with deeply pod- zolized Pleistocene cliff-top dunes that stand between 100 and 400 feet above present sea level. According to Voisey (1934), the headlands are composed mainly of sandstones, tuffs, mud- stones, claystones and shales with minor con- glomerate bands. These deposits, termed the eS Swamp _ a? Bedrock Coast (Pleistocene) = Sampling Sites Borehole Sections Brees ANS PATONGA ; Bs LBs: Seana SYSTEM Kempsey Series, are believed to be of Permian age. The hinterland of the Mid-North Coast forms part of the New England Plateau which is composed predominantly of Palaeozoic rocks, and Tertiary basalts. The Macleay is the largest river on the Mid-North Coast, and its head- waters occupy valleys which have been incised into the New England Plateau. No deltas have been built seaward of the modern coast in northern New South Wales. Instead sedimen- tation and alluviation have taken place between an ancient bedrock coastline and the dual barrier systems, resulting in the construction of fluvial- deltaic plains. yy a TOCENE S aa” S45 ea LF Fota Say, Hee XN < 4 UMINA-WOY Wor HOLO E TTALONG BOX HEAD BROKEN — BAY BARRANJOEY Fic. 2—Map to show the location of barriers in Broken Bay. 24 J. R. HAILS “:\GRASSY HD. et s 279-280 275-276 1°72 KOROGORO PT. (HAT HD) 2 PA177-186 st WO P168-169 ae fi EAST KEMPSEY ‘WEST, KEMPSEY. FRONT BEACH pt 165-167 163: 1644 "Sea : VDULCANGHI. °.. : $ 115-162 a Sie MAE: Pe [Ser om TN fe 91-93 ts CRESCENT HEAD pa 89-90 BACK BEACH RACE COURSE HEADLAND “4 DELICATE NOBBY 37-49 C7 BIG_HILL gp 13a-13b i ra POINT PLOMER {7a7p Saltwater Lake ; “Sy || —PORT MACQUARIE fo XC RE Nea O% \7 RO 4 = Queens Lake Oe, TT -SDUNBOGAN }\) CAMDEN HAVEN (LAURIETON ) IY “osc Watson Taylors of Lake Bere Sx. DIAMOND OR ADINDIAN HD. oH HY “6 Sample locations & nos, 2-50-71 Bore-hole sections & nos pee ALLUVIUM, ESTUARINE SANDS AND MUDS. =] SANDS, GRAVELS. a CONGLOMERAIE TERTIARY BASALTS, TRACHYTES. aS di SHALES SANDSTONES, 5 NY ay CROWDY| MESOZOI CONGLOMERATES it WR fei HEAD Pees LOWER MARINE SERIES, SHALES, PERMIAN SANDSTONES, LIMESTONES, TUFFS. CARBON- SHALES, SANDSTONES, IFEROUS LIMESTONES, TUFFS, LAVAS. IGNEOUS [’ INTBU- A GRANITES, MONZONITE. = SERPENTINE. 7 PLEISTOCENE SHORELINE AND OFFSHORE ISLANDS. ‘HARRINGTON (c) The Aims of the Study : The purpose of this study has been : 1. To trace the sources of the heavy minerals. Sources can be sub-divided into: indirect sources, such as material being reworked from immediately offshore, and direct sources, whereby minerals are derived from eroded adjacent cliffs and headlands. 2. To evaluate the percentage variation of the different minerals in Pleistocene and Holo- cene barrier and dune sands in order to determine whether there is any significant difference with age. An assessment has been made of the chemical stability of the heavy minerals and their resistance to abrasion. The percentage concentration of heavy minerals in barrier and dune sands has been examined in an attempt to assess the transporting effect of wind and wave action. 3. To compare the heavy minerals collected in the inland drainage basins of the Hastings and Macleay Rivers with those in coastal deposits to see if any diagnostic minerals have been transported alongshore. Also, to ascertain whether heavy minerals by-pass river, creek and lagoonal outlets, and are transported around headlands or promontories by littoral currents. Because serpentine outcrops on the Mid-North Coast south of the Hastings River, the area between Port Macquarie and Grassy Head has been studied in detail (Figure 3). The writer considered that a few diagnostic minerals derived from serpentine rocks might be trans- ported around Point Plomer, Big Hill, Delicate Nobby and other headlands flanking the arcuate bays. 4. To determine the roundness values of the heavy minerals in order to ascertain, if possible, the relationship between roundness and environ- ments of deposition in the three physiographical areas. Field and Laboratory Procedures Barrier, dune (including cliff-top dune), fluvial and offshore neritic environments were sampled. Beach samples were collected just below the swash line of high water (HWM) and approxi- mately at Bascom’s (1951) “ reference point ”’ which is the part of the beach subjected to wave action at the mid-tide stage. Although mid- tide refers to a level half way between the previous high-tide and the succeeding low, the inter-tidal zone varies from its predicted position Fic. 3—Locality map of the Mid-North Coast showing — location of heavy mineral samples. Geology based on ~ the work of Voisey. | NATURE AND OCCURRENCE OF HEAVY MINERALS 25 according to local conditions at the time of sampling. Barrier and dune samples were collected at one-foot intervals from boreholes sunk along surveyed transects across the barriers and deltaic plains. Lines of section were approximately perpendicular to the beach and extended from low water mark to a degraded coastline behind either the barriers or deltaic plains. No samples were collected below the water table because of the risk of contamination by material washed into the boreholes. Samples collected from the swamps and deltaic plains which contained a high content of silt and clay were analyzed by the hydrometer method of Bouyoucos (1936). All sand samples were oven dried and a 100 gm. sample split was sieved through a set of B.S.S. 8-inch sieves at the +(®) phi interval ona Ro-Tap machine for 15 minutes. The fractions retained on the sieves were weighed on a Mettler Precision Balance to 0:01 gm. and amounts smaller than 1 gm. were weighed to 0-001 gm. Tests showed that very few, if any, heavy minerals occurred in the —60 mesh (0-251 mm.) grade of sand. Therefore, only the —60+200 mesh (0-251-0-:074 mm.) fractions were retained for heavy mineral analysis. The light and heavy mineral fractions of a 5-gram sample split of each sample were sepa- rated in bromoform (S.G. 2-90) by using a centrifuge. The heavy residue was weighed and recorded as a weight per cent. A part of the heavy mineral residue, obtained with a micro- splitter, was mounted in Canada balsam for Microscopic examination and grain counts. In addition, microscope slides were made of the light-heavy, and rutile-zircon-ilmenite fractions of samples specially treated at Mineral Deposits Laboratory, Crescent Head, N.S.W. The per- centage number of each mineral in an individual sample was determined by using a mechanical stage and by counting 300 grains. Dryden (1931) suggested that 300 counts is an optimum number, and also that the accuracy of the counts increases as the square root of the number of grains counted. The heavy mineral frac- tions of six samples collected from the Macleay and Hastings Rivers (Numbers 1, 2—2a, 3a-3b, and 306, Figures 3 and 8) were separated into magnetic and non-magnetic fractions by using a Model L-1 Frantz Isodynamic Separator. The unmounted portion of the heavy residue of each sample was examined under a binocular microscope, and roundness analyses were con- ducted by following the method of Shepard and Young (1961). They modified the scale developed by Powers (1953) by introducing “ pivotability ’’, whereby grains were viewed under a binocular microscope and compared visually with a scale of roundness (pivotability) which is divided into six categories. In order to prevent operator bias the samples were renumbered, so the writer was unaware of their location. 100 grains were counted in each sample. The accuracy of heavy mineral analyses, depending upon errors in both field sampling and laboratory studies, has been discussed by Dryden (1931), Krumbein and Rasmussen (1941), Man- ning (1953) and other workers. Rubey (1933) stated that large variations in the relative abundance of various minerals will be found in different grain sizes of the same sample. On the other hand, Van Andel (1955) and Poole (1958) concluded that only in special cases is it necessary to study various size fractions sepa- rately. In the hght of more recent work by Carroll (1957) the writer considers that the method employed in this study has been valid and has not impaired the final results. Carroll (op. cit.) pointed out that procedural errors can probably safely be neglected from the mineralo- gical point of view when minerals have been subjected to previous sorting and sedimentation processes, even though it is recognized that certain minerals tend to occur in larger or smaller grain sizes than others. Heavy Mineral Occurrences (a) South Coast Sambles : Tourmaline, amphiboles (chiefly hornblende), pyroxenes (chiefly titan-augite and diopsidic augite), members of the epidote group, and the opaques are the most common minerals in the South Coast beach and barrier samples. The opaque minerals and tourmaline constitute 70 and 80 per cent respectively of the heavy fraction in the Pambula and Eden barrier sands, whereas these minerals plus the amphiboles and epidote comprise 86 per cent of the total heavy mineral assemblage in the Boyd Town samples. In addition, andalusite, zircon, enstatite, topaz, rutile, sphene, garnet (colourless and pink), monazite and other minor constituents have been identified. With the exception of andalu- site, the other minerals do not occur in sufficient quantities to be of importance. The variation in percentage of these minerals is shown in Figure 4, and listed in Tables 1 and 2. Table 1 compares the heavy mineral concentrates of barrier and dune sands in the three study areas. J. R. HAILS PAMBULA BARRIER SN aN Sin SINS ORO q SO J S G8, SX OS x wr AX roe Lx) 543) Sy CX \p og a 7 , X] Oo PERCENTAGE 7 SAMPLE NUMBERS OTHERS AMPHIBOLES (Predominantly HORNBLENDE ) TOURMALINE OPAQUE MINERALS Average TWOFOLD BAY —BOYD TOWN BEACH RIDGE SYSTEM % 2A al UA yl ll ill NN Ke alll 4 S \A SS 4) vn SS SS Ap RASS A SOK. x & XX x Sete Lx x on mas ~KKKX g << x CLOSED CX —SOOCOCEQOCOCCCCOCOCCCSD. ‘< % < a. xX x >. xX XX Ss te a x Oe OK CO - Average l 4 BOON RY | ot Sy Oo RO x CS, SSI 555 CP, ox 55 SS OS <7? ox i, DELICATE NOBBY (Ss) NSSIPOINT PLOMER £25 Eh rat air m SETTLEMENT ° 4 cea RIN LidS YaINYVE VONOLVd nee NIVId Y3INYVEe NOS TUM~VIEV a ies Oe chad Ba kl WSLSAS 390I4¥ HOV3SS AGSON SLV9INSd EF qo ada rasa ° 30.9 aakK Minerals. J. Sed. Petrology, 16, 91-96. GARDNER, D. E., 1955. Beach-sand Heavy Mineral Deposits of Eastern Australia. Bur. Min. Resour. Aust., Bull. 28, 1-103. Hairs, J. R., 1964. A Reappraisal of the Nature and | Occurrence of Heavy Mineral Deposits along Parts of the East Australian Coast. Aust. J. Sev., 27, 22-23. Hats, J. R., 1968. The Late Quaternary History of Part of the Mid-North Coast, New South Wales, Australia. Trans. Inst. Br. Geogr., 44, 133-149. NATURE AND OCCURRENCE OF HEAVY MINERALS 39 Hairs, J. R., 1969. The Origin and Development of the Umina-Woy Woy Beach Ridge System, Broken Bay, New South Wales. Austr. Geogr. (In press.) EiAEL, L. R., 1957. The Stratigraphy, Structure and Mineralization of the Devonian Strata near Eden. Dept. Mines Tech. Rep., 5, 103-116. Jones, O. A., 1946. Heavy Mineral Beach Sand Concentrates. Aust. J. Scz., 8, 99-103. KRUMBEIN, W. C., AND RASMUSSEN, W.C., 1941. The Probable Error of Sampling Beach Sand for Heavy Mineral Analysis. J. Sed. Petrology, 11, 10-20. LANGFORD-SMITH, T., AND THom, B. G., 1969. New South Wales Coastal Morphology. J. Geol. Soc. Aust. (In press.) Linpsay, J., 1963. Geology of the Macleay Region, North Coast of New South Wales. M.Sc. thesis, University of New England, Armidale. Manninc, J. C., 1953. Application of Statistical Estimation and Hypothesis Testing to Geologic Data. J. Geol., 61, 544-556. PETTIJOHN, F. J., 1941. Persistence of Heavy Minerals and Geologic Age. J. Geol., 49, 610-625. PooLte, D. M., 1958. Heavy Mineral Variation in San Antonio and Mesquite Bays of the Central Texas Coast. J. Sed. Petrology, 28, 65-74. Powers, M. C., 1953. A New Roundness Scale for Sedimentary Particles. J. Sed. Petrology, 23, 117-119. RuBey, W. W., 1933. The Size Distribution of Heavy Minerals Within a Waterlain Sandstone. J. Sed. Petrology, 3, 3-29. SHEPARD, F. P., AND YOUNG, R., 1961. Distinguishing between Beach and Dune Sands. J. Sed. Petrology, 31, 196-214. STEINER, H., 1966. Depositional Environments of the Devonian Rocks of the Eden-Merimbula Area, N.S.W. Ph.D. thesis, Australian National Uni- versity. (Unpublished.) VAN ANDEL, Tj. H., 1955. The Sediments of the Rhone Delta. II. Sources and Deposition of Heavy Minerals. Verh. Kon. Nederl. Geol. Mijnbouwk Gen., 15, 515-543. VoisEy, A. H., 1934. A Preliminary Account of the Geology of the Middle North Coast District of New South Wales. Proc. Linn. Soc. N.S.W., 59, 333-347. WHItTWorRTH, H. F., 1956. The Zircon-Rutile Deposits on the Beaches of the East Coast of New South Wales, with Special Reference to their Mode of Occurrence and the Origin of the Minerals. Tech. hep. Dept. Mines N.S.W., 4, 60 pp. (Received 14 December 1967) Explanation of Plates PiLatEs 1A-1C Heavy minerals in A. Hat Head cliff-top dune samples. B. Smoky Cape cliff-top dune samples. C. Front Beach transgressive dune samples. 1. Piedmontite, 2. Zircon, 3. Rutile. 4. Tourmaline. Pirates 1D-1'I’ Heavy minerals in D. Boyd Town beach ridge system. *A—Amphibole. E—Epidote. H—Hornblende. ( x 58.) ( X 36.) ( x 36.) 5. Leucoxene. 6. Magnetite. 7. Andalusite 8. Ilmenite. ( x 36.) T/Aug—Titan-augite. P—Pyroxene. E. Whale Beach barrier. (x 36.) M—Magnetite. F, Pambula barrier spit. (x 58.) G. Number 3a-30, Fig. 3, north of Port Macquarie. An—Andalusite. H. Patonga barrier spit, Broken Bay. R—Rutile. ‘I’. Macleay River—Sherwood Bridge. T—Topaz. T—Tourmaline. ( x 36.) Z—dZircon. (x 36.) * Same symbols as for D‘I’ unless shown otherwise. MOURNAL ROYAL SOCIETY-N.S.W. HATES PLATE TAG A JOURNAL TROVAL SOCGLEIY eNeSay HAILS PLATE “Ds Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 41-55, 1969 Stratigraphy and Structure of the Palaeozoic Sediments of the Lower Macleay Region, North-eastern New South Wales JOHN F. Linpsay* ABSTRACT—The Palaeozoic sedimentary rocks of the lower Macleay region have been divided into six stratigraphic units which are, in ascending order ; the Boonanghi Beds, the Majors Creek Formation, the Kullatine Formation, the Yessabah Limestone, the Warbro Formation and the Parrabel Beds. The lowest exposed Carboniferous sedimentary rocks are turbidites ; these pass upwards into poorly-washed sandstones and mudstones, which are in turn overlain by a well-washed shallow-water sequence of sandstones, conglomerates, and mudstones. The oldest Permian rocks exposed are bioclastic limestones that pass upwards into interbedded mudstones and sandstones, some of which are laminated. There are two distinct sets of faults, one intersecting and displacing the other, and a set of major folds carries some incongruent minor folds. Introduction This paper presents data on the stratigraphy and structure of Palaeozoic sedimentary rocks exposed in the lower Macleay region to the west of Kempsey, in northeastern New South Wales. The region is approximately 34 miles (54 km.) long and 21 miles (84km.) wide and has an area of approximately 700 square miles (1800 km?). It includes part of the coastal lowlands and part of the escarpment leading up to the New England Tablelands. The elevations range from 500 to 3,000 feet (150 to 900 m.). Previous Investigations Early maps show Devonian and Silurian rocks in the Kempsey district. De Koninck - (1898) described fragmentary fossils that appar- ently came from the mudstones associated with the Yessabah Limestone, and considered them to be probably of Devonian age. Dun (1898) listed a collection of fossils from six miles (9-7 km.) west of Kempsey, probably from the vicinity of Gowings Mountain, and assessed their age as Permo-Carboniferous. _ Woolnough (1911) gave the first account of the areal geology of the Macleay district, _ produced a sketch map, and described briefly _the Yessabah Limestone at Moparrabah and | Mount Sebastopol. He concluded that the limestone was Permo-Carboniferous in age and | suggested a correlation with limestone at * Present Address: National Aeronautics and Space | Administration Manned Spacecraft Center, Houston, | Texas, U.S.A. Pokolbin in the Hunter Valley. Woolnough correlated rocks underlying the limestone with the Lochinvar beds of the Hunter Valley. A later reconnaissance sketch map by Carne and Jones (1919) showed all the known localities of the Yessabah Limestone. They also gave a brief description and some chemical analyses of the limestone. The geological map of the Commonwealth of Australia published in 1932 showed the district as consisting of ‘‘ Lower Marine ”’ rocks with Carboniferous to the south. The ‘‘ Nambucca Phyllites ’’ were shown to the north of the “Kempsey Area Fault’’, and assigned to the Upper Silurian. A more detailed regional map was published by Voisey (1934), who defined the Parrabel Anticline, made the first stratigraphic divisions of the sequence, and correlated the units with similar units elsewhere in eastern New South Wales and Queensland. Voisey (1936) described the results of detailed mapping of the structural complex in the vicinity of Yessabah, and he mentioned the district later in two papers on the Manning River region (Voisey, 1938, 1939a). In 1945 he correlated Carboniferous sequences throughout New South Wales and included some discussion of the lower Macleay region ; and in 1950 and 1958 he discussed the strati- graphic divisions of the sequence, and suggested correlations. Campbell (1962) provided the first detailed age correlation for part of the Carboniferous sequence by describing two faunas from the Kullatine Formation. 42 JOHN F. LINDSAY Stratigraphy Most of the sedimentary rocks exposed in the lower Macleay region range in age from Lower Carboniferous to Lower Permian. Locally the hill tops are capped by river gravels of probable Pleistocene age. The Palaeozoic sedimentary rocks of the lower Macleay region are at least 27,000 feet (8,200 m.) thick (Fig. 1). The Carboniferous sedimentary rocks range from turbidites at the base of the sequence to near-shore traction-current deposits at the top. The Permian sedimentary rocks are mainly interbedded sandstones and mudstones and have at their base a comparatively thin but very distinct crinoidal limestone. Retaining Voisey’s (1934, 1936, 1950, 1959) original nomenclature where possible, the author has divided the Permian and Carboniferous succession into six lithostratigraphic units (Fig. 2). In ascending order these are: the Boonanghi Beds, the Major Creek Formation, the Kullatine Formation, the Yessabah Lime- stone, the Warbo Formation and the Parrabel Beds. Other sedimentary rocks are discussed under “‘ Undifferentiated Palaeozoic Sediments ” and “ High Level Gravels ”’. Boonanght Beds The Boonanghi Beds were defined by Voisey (1934). The name is derived from the parish of Boonanghi. The unit comprises turbidites consisting mainly of regularly-graded lithic sandstone interbedded with laminated mud- stone. Exposures of these sediments described by Voisey (1936, p. 186) along Dungay Creek are 1695 feet (519 m.) thick and are here defined as the type. Lithology.—The unit consists mainly of inter- bedded sandstone and mudstone in a typical turbidite sequence, and contains infrequent beds of conglomerate with a discontinuous framework. Sandstone is more abundant to- ward the top of the unit, whereas laminated mudstone is the dominant rock type lower in the sequence. The sandstone is highly indurated, dark blue to blue green, relatively coarse- grained and poorly-sorted, and the grains are highly angular. Beds range from 1 inch to 20 feet (2-5cm. to 6m.) thick. Individual beds are graded and some contain angular chips of the underlying mudstone. The lower contacts of the beds are sharp and scour chan- nels are common. Many beds have gradational upper contacts, whereas others have sharp upper contacts. Mudstone forms approximately 87 percent of the lower part of the unit but only 10 per- cent of the upper part. Most of it is laminated, with alternating dark and light laminae between 0-25 and 4 inches (0-63 and 10cm.) thick. The laminae are graded, cross-bedded, or structureless. The graded laminae are less than 0-05 inch (1-3 mm.) thick and are highly carbonaceous. The cross-bedded laminae are light-coloured and range from 0-2 to 0-5 inch (5 to 13 mm.) thick. They are generally weakly cross-bedded with the cross-beds lying at a low angle to the bedding plane. The structureless beds are hght-coloured and much thicker than other beds (as much as 4 inches (10 cm.) thick). Worm trails occur in large numbers on the bedding planes and some are as much as 2 feet (60 cm.) long. Worm borings are present in some beds but are not as common as the trails. Soft-sediment distortion of bedding occurs in the mudstone at numerous localities and ranges in intensity from slight crenulations to complex overfolds and pull-apart structures. Conglomerate with a discontinuous framework occurs at irregular intervals throughout the Boonanghi Beds but is more abundant in the basal portions. The beds are massive and range in thickness from 2 to 90 feet (0-5 to 27 m.) ; individual beds persist for as much as 5 miles (8km.). At some localities a single unit consists of 3 or 4 individual beds of conglomerate. The upper and lower contacts are sharp and the base of many bedsisaslight unconformity. The conglomerate consists of 5 to 30 per cent rounded phenoclasts as much as 8 feet (2-4 _m.) in dia- meter and of a wide variety of lithologies. The phenoclasts are set in a fine-grained matrix of soft black mudstone or labile sandstone. The conglomerate at most localities contains slabs of laminated mudstone or armoured mudstone balls. The mudstone slabs reach 15 feet (4-6 m.) in length in some beds and are highly contorted. Thickness.—Detailed measurements along Dungay Creek show the beds to be at least 5200 feet (1590 m.) thick. Relation to Older Formations.—The base of the beds is not exposed in the area studied. The fact that the beds are subhorizontal and occur © in the crest of an anticline suggests that the base of the beds probably is not exposed in adjacent — areas. Fauna and Age.—Voisey (1934, 1936) recorded | the occurrence of Loxonema sp., Rhipidomella sp., and fragmentary fenestrate bryozoa, gastro- pods, and lamellibranchs. On _ the basis of | 43 STRATIGRAPHY AND STRUCTURE OF PALAEOZOIC SEDIMENTS ‘yorrystp Avopoeyy oy} Jo dew [eorsojoey T ‘Olt SNOILVLS Sl¥l VY oiswa - ap 7 aisy. op s3%aa PE] 3NO1S3wi7 Hvavss3, a SGVOH - BLINILNAdU3S ~ s 4 43QW3W 3NO1S3NI7 LNYSV31d in m SIMIGCELS 00) IGN GNLE SEIEMIS. 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LINDSAY these fossils he correlated the Boonanghi Beds with “ the Burindi Series of the Hunter Valley ”’. The fossil material was re-examined by the writer and it was found, as indicated by Voisey, that the fossils were too fragmentary to allow accurate determination of species. Majors Creek Formation The Majors Creek Formation is here defined as those sediments composed dominantly of massive labile sandstone and cherty mudstone that conformably overlie the Boonanghi Beds. The type section is defined as the section exposed along Majors Creek from 31°01-5’S, 152° 28-6’ E (Mooraback Military Map Sheet 334/8) to 30° 58-2’ S, 152° 31-7’ E (Bellbrook Military Map Sheet 325/8), which includes over 7,000 feet (2,100 m.) of sediments. It appears that Voisey (1936, p. 187) included this formation in his Kullatine Series for he states ‘“‘ the lower beds of the Kullatine Series consists of sandstones, tuffs, sandy tuffs and breccias showing a great deal of variation in texture and composition, but possessing a general dark or light grey colour ”’ and that they “must represent several thousands of feet of to by Voisey appear to be the labile sandstone here included in the Majors Creek Formation. Distribution.—The Majors Creek Formation is.~ exposed in a broad belt following the form of the Parrabel Anticline. The belt is generally con- tinuous and is only slightly disrupted by minor faults. Lithology.—The formation is a traction current. deposit of lithic sandstone and cherty mudstone.. The mudstone is black or dark blue, cherty, and has a rough conchoidal fracture. Most beds. are massive and vary in thickness from 2 inches. (5cm.) to 3 feet (0-9m.). A few beds are: laminated ; some contain a little carbonaceous. material. The sandstone is blue or blue-green, fine- grained, and bedded in units from 2 to 12 feet (0-6 to 3-7 m.) thick, with an average thickness. of about 4 feet (1-2m.). The contacts of indi- vidual beds are sharp where the sandstone is. inter-bedded with mudstone, but are confused. by jointing where several sandstone units are bedded together. Some of the units are cross- bedded ; these units average 6 inches to 1 foot material’. The tuffs and sandstones referred (15 to 30 cm.) thick. — 1000 Feet INTERVALS. — KUNDERANG BROOK. reread aap ean cate CARRAI - DAISY PLAINS ROAD. a 2 8. $.2 2°. 5 8 ee | le s 5 yi a a e eit pata BRUINS GULLY. =.) 2! 2 m S = Sop a z= m =] 4 = & m a MAJORS CREEK . STONY CREEK . TEMAGOG CREEK . OAKY CREEK. Se ae THES” =©COMMONG CREEK . | MAJORS CK. FM. IKULLATINE FM. a WARBRO FM. PARRABEL BEDS ae 7,) (72) oal= > 2S Fig. 2 Stratigraphic sections of the sedimentary rocks of the Macleay district. STRATIGRAPHY AND STRUCTURE OF. PALAEOZOIC SEDIMENTS 45 Thickness.—In the type section the formation is 7,000 feet (2,000 m.) thick, but to the south it may be considerably thinner, as discussed below. Relationship to Older Formations.—The contact between the Majors Creek Formation and the Boonanghi Beds appears conformable. The change in lithology resulted. from a change from turbidity current transport to traction current transport. In the relatively inaccessible portion of the area to the south, the boundary between the two formations may transgress time planes and the Majors Creek Formation may disappear almost completely in the vicinity of Kunderang Brook. This change was apparently the result of a deepening of the basin to the south so that there the action of turbidity currents persisted to a much later time. Fauna and Age.—Two fossil horizons have been found in the Majors Creek Formation. The lower horizon contains a branchiopod-bryozoa fauna, characterized by Levipustula levis Max- well, which is similar to a fauna described by Campbell (1962) from the overlying Kullatine Formation. Species identified include: Levi- pustula levis Maxwell, Spinuliplica spinulosa Campbell, Neospirifer pristinus Maxwell, Com- posita magnicarina Campbell, Fistulamina fron- descens Crockford, Fenestella spp., Schizodus sp. and Peruvispira sp. The presence of this horizon containing the Levipustula fauna 3,000 feet (915 m.) below the fauna described by Campbell from the Kullatine Formation poses several problems. Campbell compared his Kullatine fauna with similar faunas in other areas and concluded that it was Westphalian in age. However, lying stratigraphically be- tween the two occurrences of the Levipustula fauna is another fauna containing the single species Cravenoceras kullatunense Campbell, which Campbell (1962) concluded to be Namurian in age. \ : / Gap Hills / > / cm Tank E Ea / ; a a rae aie f eee a \/ au aon 2 \ aoe : cm ON Broken alee z i Dam, ° \t by i i | na r— ize te A EN o] : =< x io = CON = = wn om i Varo / anc (Gas om Sandstone A tank = far rem ra \ \ Dd \ Be GaN {| filee=ny » TES S| a a \ =a f=] = go 4 LY tas Jim~ oN Ps Gas an jit 1 ae a Sa lia ay tes) Ee ae ae os = ic) C3 _ 4 SS aan frases] eat] i aa a SSS | fee) em] (a> Pl] fre] ae) =a ry ‘ MAP 1. STRATIGRAPHY AND STRUCTURE OF PART OF BARRIER RANGES 59 GEOLOGY OF PART OF THE FOWLER'S GAP AREA 0 Se MILE l QUATERNARY ALLUVIUM AND COLLUVIUM [e/Nal TALUS ? TERTIARY LATERITE (Ferricrete) GREY BILLY (Silcrete) ? LOWER TERTIARY SEDIMENTS (Siltstone and Sandstone) UPPER DEVONIAN SANDSTONE 0 CONGLOMERATE SILTSTONE QUARTZITE MARKER EE UPPER PROTEROZOIC QUARTZITE SHALE QUARTZITE FINE GRAINED SHALE HWADES DOLOMITE QUARTZOSE SANDSTONE QUARTZITE N.S. W. CocO RANSE BEDS NUNDOOKA SANOSTONE FOWLER'S GAP BEDS FAR-AWAY HILLS TEAMSTERS CREEK ESTABLISHED BOUNDARY-POSITION ACCURATE rf ESTABLISHED FAULT POSITION UNCONFORMABLE x: MINING ACTIVITY GEOLOGY BY C.R. WARD REOUCED FROM BY G.MENGYAN. 1 INCH TO 20 ANO CHAIN BOUNDARY C.N. WRIGHT-SMITH ESTABLISHED BOUNDARY—POSITION APPROXIMATE ESTABLISHED FAULT POSITION ACCURATE APPROXIMATE 1967. ORIGINAL MAPS QUARTZITE BEDS 60 MAP 1 ADJO LEGEND QUATERNARY avila TERTIARY [TLL] Sreybilty (sitcrete) DURICRUST DEVONIAN ALLUVIUM Pebbly sandstone COCO RANGE BEDS CAMBRIAN Quortzite Shole UPPER PROTEROZOIC a Limestone Quartzite Shale VHT) Quartzite Shole Quartzite LINTISS VALE BEDS CAMELS HUMPS QUART ZITE N Shale FOWLERS GAP BEDS Limestone FAR-AWAY -HILLS Quartzite QUARTZITE Shole with dolomite lenses Quartzite Tillite EURIOWIE BEDS Shale Dolomite Basic igneous dykes | SHEE OM ae Established boundary-position accurate Established boundary -position approximate ——~— +Unconformable boundary FOLDS a Syncling te Anticlinge FAULTS Established toult-position accurate Established fault position approximate —1-?- Proboble fault Geology by NFTAYLOR Jacaer DOWNS BEDS INS WARD, C. N. WRIGHT-SMITH AND Ne E. TAYLOR FARNNEL SUB-~GROUP TEAMSTERS CREEK BEDS GEOLOGICAL BOUNDARIES TORROWANGEF GROUP GEOLOGY OF THE STURTS MEADOWS AREA , N.S.W.. MILE INTERPRETATION SS AIR PHOTO b> BORE FIELD MAPPNIG ¢) CIFAR= AWAY -\ L . 6OxE ——————— STRATIGRAPHY AND STRUCTURE OF PART OF BARRIER RANGES Similar, but less intense veining also occurs along the axes of the gentle folds in these sandstones. The Upper Devonian strata are folded into an easterly plunging syncline in the Coco Range, and a broad anticline east of Sandstone Tank. In the Coco Range the dip of the beds at the unconformity with the Proterozoic strata is 10 to 20 degrees to the north-east, and near Willow Tree Bore in the south it is also 20 degrees north-easterly. Dips of 45 to 60 degrees at the unconformity were noted, immediately east of Fowler’s Gap, but these are probably due to the Nundooka Creek Fault. 61 East of the Nundooka Creek Fault the Devonian strata of the downthrown block show dips increasing from 9 degrees to 60 degrees easterly, until they are overlapped by Quater- nary sediments. Folding of the Proterozoic Strata to form the Caloola Syncline and Sturt’s Meadows Anticline commenced before deposition of the (?) Cambrian strata of the Acacia Downs Beds. The genera- tion of faults within the syncline mentioned above took place probably at the same time, but at least before the Upper Devonian beds were deposited. The Upper Devonian Coco Range Beds and Nundooka Sandstone were E 31°00" PROTEROZOIC oma a= Cat ARCHEAN A ANTICLINE Sé& SYNCLINE FAULT — POSITION ACCURATE ~ EAWET= POSITION APPROXIMATE “uy UNCONFO RMITY MARKER HORIZON id § MILES AFTER N.S W. DEPT. rides Fic. 3.—Structural elements. 62 C. R. WARD, C. N. WRIGHT-SMITH AND N. F. TAYLOR deposited and folded prior to the formation of the Nundooka Creek Fault. Since this faulting there have been slight changes in climate or elevation with silcrete and talus deposits having formed and being eroded under the present physiographic conditions. Stratigraphy The succession of strata discussed below in detail is based on the field work of the authors. Seven rock units are recognized and named by the authors, and two others are mapped which have been named by other workers. Strata of the Upper Proterozoic Torrowangee Group are unconformably overlain by strata thought to be Lower Cambrian in age. Sand- age also overlie the Precambrian rocks with a strong angular unconformity, but nowhere within the area mapped are these strata in contact with the Cambrian beds. Horizontal beds of sandstone and siltstone thought to be Lower Tertiary age are found in one small part of the area. Scattered residuals of duricrust in the form of silcrete and ferricrete also occur, and there are substantial deposits of Quaternary fluviatile, aeolian and colluvial sediments. The assignment of ages to most of the rock units mapped is only on a tentative basis, because very few fossils were found in the entire sequence. The rock units are summarized stones and some shales of (?) Upper Devonian in Table 1. TABLE 1 Stratigraphy Era Epoch. Group Formation Lithology Thickness Remarks (feet) Quaternary Alluvium Silt and clay and 300 Penetrated by bores some sand Upper Tertiary ? Duricrust Silcrete and some 10 See also Langford- v ferricrete Smith and Dury (1965) S and Dury (1966) 4 Lower Tertiary ? Sandstone and silt- 200 Age uncertain—similar rs stone sediments to the north Upper Devonian ? Nundooka Quartzose sand- 3,500 Downthrown. block of sandstone stone and Ortho- Nundooka Creek Fault 0 quartzite Named by authors rs) Coco Range Beds Quartzose sand- 2,500 Upthrown block of o stone and _ ortho- Nundooka Creek Fault Z quartzite, pebbly —Unconformably over- 4 sandstone, red and lies Proterozoic x green shale Named by authors Lower Cambrian ? Acacia Downs Beds Quartzite and shale Fossils reported but not found by authors unconformably over- lies Proterozoic Named by B. Warris & ( Lintiss Vale Beds Cleaved shale with 4,000 Named by authors Ska ABC quartzite and lime- O D & stone 5 2 | Camels Humps Quartzite with 700 Marker horizon 5 © — | Quartzite shale Named by authors = Fa fa] es < Fowler’s Gap Beds Shale and quartzite 10,000 Named by authors < Hi a a with few limestone (approx.) % 2 2 © lenses = A = & | Faraway Hills Quartzite 300 Marker horizon A fa 9 & | Quartzite Named by authors g = 4 Teamsters’ Creek Shale with dolo- 6,000 Named by authors a 5 & Beds mite lenses (approx.) Euriowie Beds Shale, dolomite and tillite Named by N.S.W.) Dept. Mines for Broken - Hill 1: 250,000 Sheet. © Rests conformably on remainder of Protero-— zoic sequence | but the top is clearly defined. STRATIGRAPHY AND STRUCTURE OF PART OF BARRIER RANGES Upper Proterozoic TORROWANGEE ‘GROUP The Torrowangee “ Series’’ of Mawson and succeeding workers has been revised as the Torrowangee Group for the Broken Hill 1 : 250,000 Geological map, by the N.S.W. Dept. of Mines. Its constituents formations include those named in this paper and several others cropping out beyond the present areas. A brief summary of the regional stratigraphic succession of the Torrowangee Group as shown on the Broken Hill 1 : 250,000 Geological Map is given below :— Top Sr Cambrian and other strata. Unconformity Farnell Sub-Group Shale and quartzite with minor limestone lenses. See details below. Shale with dolomite lenses and tillite-hke phases. Laminated tillite-like shale, dolomite and limestone, sand- stone and conglomerate. Conglomerate, sandstone numerous erratic pebbles and Teamsters’ Creek Beds Euriowie Beds Yancowinna Beds boulders of possible glacial origin ; some limestone. Pintapah Quartzite Quartzite, sandstone, pebbly quartzite. Wilangee Volcanics Unconformity Basalt, epidotized basalt. WILLYSMA COMPLEX Only the upper part of this sequence including the Farnell Sub-Group, the Teamsters’ Creek Beds and part of the Euriowie Beds are found to crop out in the area mapped. Details of these stratigraphic units are given below. EURIOWIE BEDS The Euriowie Beds are named by G. Rose for the Broken Hill 1: 250,000 Geological Map. They crop out in the south-west corner of the area mapped in the present study, where they are exposed in the Sturt’s Meadows Anticline. The base of the unit is not seen in this area, It is taken as the top of the tillite marker horizon, including its laterally equivalent quartzite horizon as mapped on the flank of the anticline. Dark grey-green shale is the lowest bed and 1s exposed on the crest of the fold. This is overlain by a sequence of grey-brown dolomite and grey-green shale. The shale often becomes dolomitic and grades into dolomite, especially in the lower part of the section. Dolomite beds 63 are generally less than three feet thick, but they persist for quite some distance along strike and help delineate the structure. It is unfos- siliferous with interlocking fine carbonate crystals and is probably recrystallized. These crystals show an apparent elongation which may either reflect bedding or a tectonic preferred alignment. Shale becomes dominant again above this unit, but dolomite beds are still present. One horizon is particularly prominent. This is made up of ten closely spaced dolomite beds and can be traced as virtually a single unit 30 feet thick for over four miles along strike. There is a layer of tillite at the top of the Euriowie Beds. This is about 300 feet thick on the eastern flank of the anticline, but on the western side, beyond the area mapped, it thickens to 1,500 feet and is much better exposed. It passes laterally into a quartzite further to the north. The tillite forms a dominant outcrop with many boulders scattered nearby. The rock assemblage displayed in these boulders is extremely heterogeneous with quartzite most abundant. Granite, gneiss, schist, basic igneous rock, shale, slate and limestone also present. The size of these fragments is also highly variable. Excluding those of the matrix, the fragments range from small pebbles and cobbles to boulders and several megaclasts with a maximum dimension of four to five feet. In sympathy with this size variation, the fragments range from sharply angular to sub-rounded and are from flat and platey to sub-spherical in shape. The tillite is conformable with the rest of the Proterozoic sequence and often shows some degree of bedding. However, the thicker deposit on the western flank of the Sturt’s Meadows Anticline is an unbedded mass of dispersed boulders. The boulders and pebbles are set in a matrix of angular sand grains and grey siliceous to blue-green argillaceous material. Well bedded, thin layers of consolidated gravel, arkosic grit, coarse grained sandstone and quartzite occur throughout the tillite on the eastern limb of the anticline. Sometimes the gravels show several cycles of graded bedding. The name “tillite”’ is applied to this rock type because of its appearance in the fleld. Although no striations were found on them, it is felt that the occurrence of such large boulders of diverse rock types, often separated by a high proportion of matrix is strongly indicative of glacial action. In view of the current importance attached to Precambrian 64 C. R. WARD, C. N. WRIGHT-SMITH AND N. F. TAYLOR glaciation on a world-wide basis (Nairn, 1964), further work on the origin of these beds may be justified. The tillite becomes more shaley and the boulders more sporadic as it grades upwards into the Teamster’s Creek Beds. TEAMSTERS’ CREEK BEDS This unit is named by the authors after Teamsters’ Creek, a water-course west of Fowler’s Gap Tank. It conformably overlies the tillite horizon at the top of the Euriowie Beds, and is in turn overlain by the prominent Faraway Hills Quartzite. It is exposed extensively along the western side of the area mapped and consists mainly of shales with limestone and dolomite lenses. The boundary between the Teamsters’ Creek Beds and the Euriowie Beds is exposed in the south-western corner of the area mapped. North and west of Fowler’s Gap its area of outcrop becomes more extensive due to the presence of an anticline and possible faulting between the Caloola and Flood’s Creek Syncline. The shale is generally grey-green in colour, but in places becomes red-brown and _ buff. White calcareous phases are also encountered. A strong axial plane cleavage has been developed in the shale, and_ recrystallization has undoubtedly obscured much of the bedding. Microscopic and X-ray determination of the mineral assemblage indicates that metamor- phism of the rock approached greenschist facies, thus the term “slate ’’ should perhaps be applied. However shale is used in this text to maintain uniformity in definitions with other workers, especially those concerned with the Adelaide Geosyncline in South Australia. In some localities the strata are more intensely deformed, with phyllites of silky lustre due to the muscovite flakes and a dark green colour due to the presence of chlorite, often developed. This is especially noticeable near the Nundooka Creek Fault. Throughout the Teamsters’ Creek Beds, but especially in the north-west corner of the area, the shales become tillitoid. Boulders, pebbles and sand-size grains of quartz, quartzite and other rock fragments are set in a fine grained lepidoblastic micaceous matrix. The boulders range up to two feet across and generally appear more rounded than the grains. The fragments are poorly sorted but occasionally elongated boulders are aligned parallel indicating either bedding or rotation association with the develop- ment of slaty cleavage. It is thought that the poor sorting and sporadic development of this coarse material in an otherwise fine grained shale is indicative of glacial action with possible ice-rafting, rather than fluviatile deposition of conglomerate. Beds of probable tillite occur lower down in the Torrowangee Group, especially at the top of the Euriowie Beds and in the Yancowinna Beds. Dolomites and limestones occur as_ lenses throughout the sequence, and are often inter- bedded with white or grey-green shales. The dolomites are generally buff in colour and contain a high proportion (about 45%) of quartz. They are cut by numerous quartz veins and it is suggested that much of the silica in these dolomites is due to replacement of carbonates. The limestones on the other hand are dark grey in colour and occur as only small lenses. They are largely free of quartz veins and contain almost no material other than carbonate. Major lenses of dolomite are shown on the map. As well as these, there are minor occur- rences of limestone and dolomite throughout the shales of the Teamsters’ Creek Beds. Two small outcrops of black, fine grained chert-like rock occur in the north-west of the area. These are comprised of quartz and muscovite, but their origin is uncertain. One of these lenses is very heavily veined with white quartz, giving a banded appearance. A long prominent ridge of white, fine grained rock is mapped just west of Fowler’s Gap. This is composed of recrystallized quartz less than 0-05 mm. in diameter with an interlocking fabric. It may represent a completely silicified bed of dolomite, although its shape is different from that of any other dolomite bed in the area, or it may be a deposit of silica (e.g. chert) which has been recrystallized. It does not appear to be intrusive as no contact effects are noted in the surrounding shale. The Teamsters’ Creek Beds are about 6,000 feet thick in the south-west of the area where both top and base are exposed. Structural complications to the north prevent any reliable estimate of thickness in the remainder of the area mapped. FARNELL SUB-GROUP Conformably overlying the Teamsters’ Creek Beds is a sequence of quartzite beds and cleaved — shale with subordinate limestone lenses. It is © distinctly different from the underlying strata — of the Teamsters’ Creek and Euriowie Beds | STRATIGRAPHY AND STRUCTURE OF PART OF BARRIER RANGES 65 because no continuous beds of quartzite are found in the latter units. The Sub-Group takes its name from the County of Farnell, Western Division in which the area lies. The unit is subdivided, as follows, into four formations, two of which are prominent marker horizons. 4,000 ft. Lintiss Vale Beds Shale with interbedded quartzite and dolo- mite. 900 ft. Camels Humps Marker horizon — two Quartzite quartzite beds _ sep- arated by shales. 10,000 ft. Fowler’s Gap Shale with numerous Beds. quartzite beds and subordinate limestone lenses. 300 ft. Faraway Hills Marker horizon—single Quartzite quartzite bed con- taining minor shale lenses. The most complete section of the Farnell Sub-Group is exposed in the Caloola Syncline, as shown on the accompanying maps. Although some erosion may have occurred, the top is at present defined as the unconformable boundary with the overlying (?) Cambrian strata in the Core of the syncline. The Broken Hill 1 : 250,000 Geological Map shows a further occurrence of these quartzites in the Flood’s Creek Syncline near Mt. Westwood, north-west of the present area. FARAWAY HILLS QUARTZITE The lowest formation in the Farnell Sub-Group iS a very prominent marker horizon consisting of a bed of medium grained quartzite 200 to 300 feet thick with occasional minor shale lenses up to 20 feet thick. It forms the highest of the ridges along both limbs of the Caloola Syncline and crops out east and west of the Fowler’s Gap Homestead. King and Thompson (1954) show it as a marker horizon for the Caloola Syncline and refer to it as “ Thirty Mile Ridge ”’. The formation takes its name from the Faraway Hills Bore, in the southern part of the area, near its outcrop. In thin section the quartzite is composed of 90% to 95% quartz, with some opaque iron oxides and traces of muscovite. The quartz shows some evidence of recrystallization and in places a cataclastic texture is present. The grain-size is up to 0:-4mm., but some of the -brecciated fragments are as small as 0:01 mm. E Recrystallization and brecciation have obliterated most of the characteristics of the original sedimentary rock. In some specimens a shear- ing effect is shown by parallelism of quartz crystals and increased brecciation. Both the sheared and the more massive types are clearly recognizable in hand specimens. FOWLER’S GAP BEDS Between the prominent marker beds of the Faraway Hills and the Camels Humps Quart- zites is a Sequence of interbedded quartzite and cleaved shale to which the name Fowler’s Gap Beds is given. Fowler’s Gap Station, from which the name is derived, lies in the centre of their outcrops on the Silver City Highway. The base and the top of the unit are defined by the top of the Faraway Hills Quartzite and the base of the Camels Humps Quartzite respectively. The quartzites are similar in appearance to the Faraway Hills Quartzite described above, although about 5-10°% of felspar (usually micro- cline), is present. The beds vary in thickness from six inches to six feet, but are very irregular and are often obscured by talus. They are often intimately interbedded with shale and the quartzite thickens, thins, splits and pinches out quite frequently. Areas shown on the map as quartzite usually include a considerable amount of shale, as lenses, or often as separate beds. Shale makes up most of the rest of the unit. It is usually ight grey-green in colour although buff and white types develop. At the top of the Fowler’s Gap Beds just below the Camels Humps Quartzite at “ Bluff’ Trig Station the shale contains several thin bands, rich in goethite, haematite and calcite. It is thought that this represents ‘ red-bed facies’ develop- ment due to erosion of lateritic material in the source area. A similar horizon is reported by Thompson (1964) underlying the Pound Quartzite in South Australia. Sedimentary structures suggestive of worm tracks are seen in the shale about two miles north-west of Willow Tree Bore. Smooth curved tracks about one eighth inch deep are associated with hemispherical pits of irregular shape and size. Small lenses of limestone and dolomite occur throughout the shales. One of these, just west of the Fowler’s Gap Homestead is seen to grade laterally through calcareous quartzite to quartzite. 66 C. R. WARD, C. N. WRIGHT-SMITH AND N. F. TAYLOR Between Faraway Hills Bore and Camels Humps the Fowler’s Gap Beds are about 10,000 feet thick. Their area of outcrop around Fowler’s Gap Homestead is greater than would be expected due to a reduction of dip angle in the synclinal limbs. Hence the quartzite beds become separated in outcrop by a greater distance and so appear to be more numerous than further to the south. CAMELS HUMPS QUARTZITE This is a very prominent marker horizon tracing out the outline of the Caloola Syncline east of Sturt’s Meadows. The formation lies conformably between the Fowler’s Gap Beds and the Lintiss Vale Beds and is readily recognized by virtue of its prominent outcrop. The best development of quartzite is near the “ Bluff’ Trig Station where the steep slopes expose the full section. The name is taken from the locality ‘‘ Camels’ Humps’’, a ridge to the east of Faraway Hills Bore. It is not a single mass of quartzite but consists of two major and one less prominent quartzite beds interbedded with shales. A typical section as exposed near the “ Bluff’”’, is as follows (thicknesses approximate). Top: 100 feet. Quartzite. 300 feet. Shale. 250 feet. Massive Quartzite. 150 feet. Shale. 150 feet. Massive Quartzite. Base. This gives a total thickness of some 900 feet. The lower two quartzites are shown as one unit on the map, and appear as a single ridge in the field. The top quartzite bed is included with the Camels’ Humps Quartzite because of its lithological similarity to the main ridge-forming bed and its persistence compared to those of the Lintiss Vale Beds. Some current markings are occasionally exposed on bedding planes of the massive quartzites and clay galls are found in the uppermost minor quartzite. These clay galls are markedly spherical, dark red inclusions in massive quartzite. They are about one to two inches in diameter and number about two or three to the square yard of exposed rock surface. LINTISS VALE BEDS Overlying the Camels’ Humps Quartzite marker there is a sequence of shales with interbedded quartzites and a dolomite horizon atthetop. These are the uppermost Proterozoic sediments in the Caloola Syncline and are unconformably overlain by strata believed to be Cambrian in age. These are named by the authors the Lintiss — Vale Beds after a property a few miles to the south. Although part of the section may have been eroded the formation is approximately 4,000 feet thick and is composed dominantly of shale with lenticular beds of quartzite in the upper half. Colluvial cover between their outcrop and the “ Bluff’? prevent a more complete study of these beds. The top of the Lintiss Vale Beds has been taken at the unconformity with the Acacia Downs Beds. Immediately beneath these (?) Cambrian strata a thin dolomitic bed occurs. This horizon is only 40 feet thick and is made up as follows. Top: 10 feet. Flaggy Quartzite. 10 feet. Dolomite. 10 feet. Quartzite. 10 feet. Dolomite. Base. The dolomites are similar to those of the Teamsters’ Creek Beds and form a shallow dipping plateau beneath the (?) Cambrian strata. Some small scale slumping has been observed in these sediments. The shales are buff-brown in colour, especially near the top of the sequence, as opposed to the more common grey-green colour typical of the rest of the Torrowangee Group in the area. (?) Cambrian AcactA Downs BEDs Resting with a slight angular unconformity on the Lintiss Vale Beds is a sequence 200 feet thick of light green-brown shale overlain by | 150 feet thick grey quartzite. It is lithologically — similar to the rocks of the Torrowangee Group | beneath. The Cambrian age assigned to these rocks is based on the reported occurrence of © fossilized worm tracks and arthropod trails — by Messrs. Fitzpatrick and Johnson of Adelaide — (M. F. Glaesner, pers. comm.), but no further — specimens were found during the present study. — This formation has been named by B. Warris © (unpublished) after the property “ Acacia Downs” to the south. These sediments are only found in small areas at the centre of the Caloola Syncline, west of the Tarnuna Tank, with an extent of about a square mile. | STRATIGRAPHY AND STRUCTURE OF PART OF BARRIER RANGES Some cross bedding has been noted in the quartzite, which has both massive and flaggy phases. Sole markings, both tool and current types, are relatively abundant. CORRELATION OF THE PROTEROZOIC The Upper Proterozoic beds of the Torro- wangee Group are separated from the type area succession in the Adelaide district by the Willyama Block, which acted as a positive tectonic element during Sturtian and Marinoan time (Sprigg, 1952), and from which much of the detritus was derived. The units in the area mapped can be correlated with the upper part of the sequence in the Adelaide Geosyncline by virtue of their environmental similarity, although they do not attain the great thickness of the type section. Table 2, gives a summary of the proposed correlation, using the rock unit names of Thompson é al. (1964) for the North Flinders Range. In the Sturt’s Meadows—Nundooka area, the most striking feature of the Torrowangee Group is the change from shales, dolomites and tillites 67 of the Euriowie and Teamsters’ Creek Beds to the persistent beds of quartzite in the Farnell Sub-Group. This is the same as in the Adelaide Geosyncline where the glacial character of the Umberatana Group gives way to the quartzites and shales of the Wilpena Group (Thompson et al., 1964). It is difficult to extend the stratigraphic correlation beyond this and attempt to correlate individual formations, largely because there is no continuous outcrop between the two areas. The Willyama Complex around Broken Hill is thought to have been a cratonic block during the late Precambrian, separating the Adelaide Geosyncline and the Torrowangee Group. Sprigg (1952) describes the derivation of the Sturtian glacials from this block, and it is quite likely to have persisted as a source area through- out the remainder of the Proterozoic. Thus the Willyama Block seems to have been in a position whence sediment was supplied to two depositional areas, at the same time. Any major climatic change or tectonic distur- bance in this block would have affected the TABLE 2 Stratigraphic Correlation of the Proterozoic Sequence System Series NORTH FLINDERS RANGES (after Thompson eé al. 1964) Z Z - is - PARACHILNA FORMATION al Am zi ae ® Ao) Local disconformity POUND QUARTZITE Gin oe eee ee 5 st 2 9 WoONOKA FORMATION a] x Py) © : £3) « BUNYEROO FORMATION Ww yn pias eaten ee i a & A.B.C. RANGE QUARTZITE m ©) 4 eS a : S BRACHINA FORMATION Qa < < = NUCCALEENA FORMATION YERALINA FORMATION UMBERATANA GROUP Rock Units STURT’S MEADOWS-NUNDOOKA (this paper) AcAcIA Downs FORMATION Unconformity 5 © LiIntTiss VALE BEDS & Camers’ Humps QuUARTZITE m i) ie FOWLER’s GAP BEDS s) 7 5 FARAWAY HILLS QUARTZITE ee TEAMSTERS’ CREEK BEDS TORROWANGEE GROUP EURIOWIE FORMATION 68 C. R. WARD, C. N. WRIGHT-SMITH AND N. F. TAYLOR type of sediment in each depositional area. A change of this type may well be responsible for the cessation of glacial activity and the commencement of deposition of quartzose sand- stones which occurs in both the Adelaide Geosyncline and the area mapped. However deposition within each of the two areas was controlled by more local effects, and a sufficiently different sequence was developed in each to make exact correlation difficult. It should also be noted that in the Adelaide Geosyncline there is an apparently conformable succession from the Proterozoic into the Cambrian, but at Sturt’s Meadows there is a distinct angular unconformity between the Lintiss Vale Beds of the Proterozoic and the (?) Lower Cambrian Acacia Downs Beds. It is possible that the top of the Proterozoic sequence in the Caloola Syncline was removed by erosion prior to deposition of the Cambrian strata, and so the succession at present pre- served there may not extend completely to the top of the Precambrian as it appears to do in the Adelaide Geosyncline. Upper Devonian Resting unconformably on a basement of Proterozoic shale at the eastern edge of the Barrier Range in the area mapped are beds dominantly of quartzose sandstone of probable Upper Devonian age. Previous published infor- mation has not recorded any fossils in these beds, but David (1950) regards them as Upper Devonian and probably equivalent to the “Lambian Stage ’’ in eastern N.S.W. Dr. M. J. Rickard (pers. comm.) has recently found some fish plates c.f. Bothriolepis sp.) in the sandstones east of Fowler’s Gap. These have an age of Middle to Upper Devonian and are probably indicative of fresh water conditions. The Nundooka Creek Fault separates these beds into two blocks. The western, upthrown block has some lithological differences from the eastern block and the two units are given separate names. Since the fault separates these units along the entire length of their outcrop the full sequence cannot be seen any- where, although they are probably strati- graphically conformable. The units recognized are: Coco Range Beds:—A sequence of quartzose sandstones and conglomerates with red and green-grey siltstones and claystones; this unit immediately overlies the Torrowangee Group with a sharp angular unconformity. Nundooka Sandstone:—A thick unit almost entirely of quartz sandstones brought down against the Coco Range Beds by the Nundooka Creek Fault. It is clear that the Nundooka Sandstone overlies the Coco Range Beds but since the fault interrupts the exposure of the sequence no further stratigraphic relationships can be observed in this area, or even to the north, near Nundooka Homestead. Coco RANGE BEDS These rest with a marked unconformity on cleaved shale of the Upper Proterozoic Torro- wangee Group. They are exposed along the eastern edge of the area but it is in the Coco Range to the north that the most complete sequence is to be seen. The vnit is named by the authors after the Coco Range (Cobham Lake, N.S.W. 1:250,000 Military sheet grid ref. 469168), where the best development occurs. At the base where it overlies the Proterozoic some red and green shaly units are exposed. These are in turn overlain by a thick sequence of conglomerates and sandstones. At least 2,500 feet of sediment is exposed in the Coco Range where the sequence is as follows :— (thicknesses approximate only) Top :—Truncated by Nundooka Creek Fault. 600 feet. Quartz sandstone. 3 feet. Green-grey siltstone. 10 feet. Pebbly sandstone and con- glomerate. 300 feet. Quartz sandstone. 600 feet. Pebbly sandstone and con- glomerate. 4 feet. Orthoquartzite. (Marker horizon). 900 feet. Quartz sandstone and ortho- quartzite. Unconformity Base :—Proterozoic Torrowangee Group. In lenticular patches above the unconformity — exposures of argillaceous material are sometimes seen. A section measured east of Fowler’s Gap Homestead at the base of the Coco Range Beds, is as follows :— Top :—Quartzose sandstone. 2 feet. Red and green claystone beds. © 1 foot. Red sandstone. 1 ft. 6 inches. Coarse grit. 10 feet. Red claystone. — Unconformity Base :—FProterozoic shale. STRATIGRAPHY AND STRUCTURE OF PART OF BARRIER RANGES 69 Where these beds are not present sandstone rests directly on the Proterozoic. This Devonian sandstone often contains angular fragments of grey-green shale derived from the Torrowangee Group beneath. The sandstones of the Coco Range Beds are medium grained, fairly well sorted and in places quite flaggy. They contain about 90% quartz and the rest consists of mica and rock fragments set in a matrix of white clay. Some iron oxide, probably authigenic, is also present. Many beds of orthoquartzite about four feet thick persist as distinct horizons both in the Coco Range and Nundooka sandstones. They are much harder than the sandstones described above, with a cemented nature due to secondary enlargement of quartz grains. This diagenetic precipitation of silica appears to have been confined to horizons of less clayey sandstone in the Devonian sequence. Small hemispherical pits one eighth to one quarter inch in diameter are often seen in the Devonian sandstones. These are left by weathering out of spherical patches, rich in clay, within the sandstone. These clayey patches may be primary or diagenetic; not unlike concretions. Flattened blebs of grey shale also occur within the sandstone. Removal of the shale on exposure leaves polygonal hollows resembling fish plates, but these impres- sions do not have any regular shape or ornamen- tation. The conglomerates contain rounded cobbles and pebbles of white vein quartz, up to four inches across, set in a sand and granule matrix. Although the proportion of pebbles varies, the bulk of the rock consists of pebbly sandstone rather than true conglomerate. The upper limit of the Coco Range Beds is not clearly defined due to truncation by the Nundooka Creek Fault. However photogeo- logical interpretation of the area to the north indicates that very little more of the sequence is likely to be exposed on the western side of the fault than seen in the area mapped. NUNDOOKA SANDSTONE _ On the eastern side of the fault, a sequence of at least 3,500 feet of quartzose sandstone is exposed. This is called the Nundooka Sand- stone after “ Nundooka”’ Station to the north. The sandstone is very similar to that of the Coco Range Beds, but no conglomerate units were observed in the area mapped. Pebbly _bands do occur in places and one very thin bed of green shale is exposed. Orthoquartzite beds similar to those described above occur with secondary enlargement of quartz. Three of these beds are persistent enough to trace as marker horizons over many miles. The base of the units is obscured due to the Nundooka Creek Fault, and the top is covered by extensive deposits of alluvium to the east. 4 Sanvy Cn. Bose Lantiss . VALE. AffeR £5. KENNY 1984 Mitts [EXJWILLYAMA C'PLEX[] ? DEVONIAN E-]TORROWANGEE GPEZ] CRETACEOUS [] QUATERNARY Fic. 4.—Regional geology Depositional Environment of the Devonian The association of quartzose sandstones with red and green siltstones and shales is considered (Pettijohn, 1957; Krumbein and Sloss, 1963) to be indicative of stable tectonic conditions. This is supported by the maturity of the sandstones and the presence of cross-bedding. The fish plates suggest a freshwater deposition (G. Rose, pers. comm.). All writers (Voisey, 1959; Packham, 1960 ; Conolly, 1962) agree that, at the commencement of the Upper Devonian time the west of N.S.W. 70 C. R. WARD, C. N. WRIGHT-SMITH AND N. F. TAYLOR was occupied by a miogeosyncline (Voisey, 1959) or molasse sedimentation conditions. This was a distinct environmental change from the engeosyncline or flysch of the earlier Palaeozoic. Conolly (1962) envisages a sea retreating eastwards throughout the Upper Devonian. The Devonian sediments in the Coco Range Beds and the Nundooka Sandstone exposed to the north and east of Fowler’s Gap probably represent the western limit of Upper Devonian sedimentation in the Lachlan Geosyncline. They rest unconformably on the quartzites and slates of the Proterozoic Torrowangee Group. The sandstones contain fragments of the underlying Torrowangee shale, suggesting that they were derived from the craton of the Broken Hill Block described by Packham (1960). However the lack of continuous outcrop between this area and the Mulga Downs Group (Conolly, 1962) at Cobar means that the strati- graphic position of these marginal sediments with respect to the remainder of the Upper Devonian sequence in N.S.W. is uncertain. ? LOWER TERTIARY In the north-west of the area mapped several silcrete capped mesas occur. These consist of approximately 200 feet of sediment, the lower half being siltstone whilst the upper section is a sandstone or granule conglomerate. Further occurrences are substantially covered by colluvium around Sandstone Tank but isolated exposures are seen in creek beds. Both the siltstone and the sandstone are very friable, although partially lithified. They are made up of quartz with a high proportion of muscovite flakes. The granule conglomerate is usually poorly sorted. A certain amount of calcareous cement is present. The Lower Tertiary age assigned to these sediment is tentative only. They are older than the widespread “ duricrust’’ or silcrete of western N.S.W. which is considered to be late Tertiary in age. (Kenny, 1934), and are believed to be younger than the Cretaceous sediments of the Great Artesian Basin (R. L. Brunker, pers. comm.). ? TERTIARY The duricrust of western N.S.W. has been studied by several authors including Wool- nough (1927), Langford-Smith and Dury (1965) and Dury (1966). In the area mapped there are several outcrops of silcrete left as residuals by the present pattern of erosion. This silcrete is typically grey in colour and contains grains of quartz set in a cement of microcrystalline silica. Some phases with less prominent quartz — grains contain plant fossils of the Cimnamonum flora. Pebbles, mainly of locally derived quart- zite, are occasionally to be found, cemented together by fine grained silica as part of a silcrete outcrop. The silcrete rests on all the above mentioned rock types including Proterozoic shales and quartzites, Devonian sandstones and the (?) Tertiary sediments described above. The out- crop east of Fowler’s Gap Tank has been noted by Langford-Smith and Dury (1965) and one south-east of Tarnuna Tank (beyond the area mapped) at Acacia Downs is recorded by Dury (1966). The other occurrences mapped have not previously been recorded. Ferricreted aggregates of rock fragments are occasionally exposed. Red-brown iron oxide material also becomes quite prominent on bedrock, especially the Devonian sandstones, and the profile resembles that of a laterite. It is younger than the silcrete since fragments of “ grey billy’ are included in the iron cemented aggregates. Calcareous material, or “ kunkar’’ is some- times seen cementing rock fragments in creek beds. It also forms a coating several millimetres thick in the base of the dry channel. This is a white, powdery deposit, often with a pinkish coloration, composed essentially of calcium carbonate. It is much younger than the silcrete or ferricrete and appears to be a precipitate from the present day stream water. QUATERNARY In the eastern part of the area and extending for some 20 miles to the Mootwingee district are flat plains of alluvium. A thickness of greater than 300 feet is indicated in some bores. It is made up dominantly of clay the colour of | which ranges from black and red-brown to white, with occasional thin sandy units. On the surface is a thin veneer of drift sand and pebbles with underlying red-brown silt and clay. Near the hills on the western margin of © the plains deposits of talus are common, con-— taining coarse pebbles of the nearby bedrock — including vein quartz, and silcrete fragments. The veneer of sand is commonly shifted by wind — action and shows ripple marks often two to — three inches high. Sand dunes are sometimes developed. | STRATIGRAPHY AND STRUCTURE OF PART OF BARRIER RANGES 71 A large area of talus is seen around Sand- stone Tank in the north of the area. This is derived from the quartzite bedrock of the nearby hills set in a silty and clayey matrix of weathered shale. This deposit is being eroded by the present stream pattern rather than being built up, suggesting a recent vertical uplift, tilting down to the east, or possibly a change in the stream pattern due to river capture. Acknowledgements The authors would like to express their gratitude to many members of staff of the University of N.S.W. both in Sydney and Broken Hill for assistance during the field mapping, especially Prof. L. J. Lawrence, who acted as supervisor, and Mr. R. L. Mercer, manager of the Fowler’s Gap Research Station. Officers of the Geological Survey, N.S.W. Dept. of Mines, especially Messrs. G. Rose and R. Brunker, who also gave invaluable help, as did Dr. M. J. Rickard of the Australian National University. Prof. J. J. Frankel, Mr. J. H. Bryan and Mr. G. Rose kindly read the manu- script and offered much useful criticism. References ANDREWS, E. C., 1922. The Geology of the Broken Hill District. Geol. Surv. N.S.W., Memoir No. 8. Cono_tty, J. R., 1962. Stratigraphic, Sedimentational and Palaeogeographical Studies in Upper Devonian Rocks of Central Western N.S.W. Unpublished Ph.D. thesis, University of N.S.W. Davip, T. W. E. (ed. Browne, W. R.), 1950. The Geology of the Commonwealth of Australia. Arnold, London. Dury, G. H., 1966. Duricrusted Residuals on the Barrier and Cobar Pediplains of N.S.W. J. Geol. Soc. Aust., 13 (1), 299-307. Geological Survey, N.S.W. Department of Mines, 1966. Cobham Lake 1 : 250,000 Geological Map. Com- piled by R. L. Brunker. Geological Survey, N.S.W. Department of Mines, 1967. Broken Hill 1: 250,000 Geological Map. (In preparation.) Compiled by G. Rose. Kenny, E. J., 1934. West Darling District. Geol. Surv., N.S.W. Dept. of Mines, Mineral Resources No. 36. Kine, H. F., aAnpb THompson, B. P., 1953. The Geology of the Broken Hill District. In Geology of Australian Ove Deposits, Ist ed. 5th Emp. Min. Met. Congr., Melbourne. KRUMBEIN, W. C., AND Stoss, L. L., 1962. Stvati- graphy and Sedimentation. Freeman, San Francisco. LANGFORD-SMITH, T., and Dury, G. H., 1965. Distri- bution, Character and Attitude of the Duricrust in the northwest of N.S.W. Am. J. Sct., 263, 170-190. Mawson, D., 1912. Broken Hill Area. No. 24, 211-319. Nairn, A. E. M. (Ed.), 1964. Problems in Palaeo- climatology. Wiley & Sons, London. PackHaM, G. H., 1960. Sedimentary History of Part of the Tasman Geosyncline in South-eastern Australia. Rep. Int. Geol. Cong., Norden, Part 2, Regional Palaeogeography. PETTIJOHN, F. J.,1957. Sedimentary Rocks. Freeman, San Francisco. SpRIGG, R. C., 1952. Sedimentation in the Adelaide Geosyncline. Douglas Mawson Anniversary Volume, University of Adelaide, pp. 153-160. Tay or, N. F., 1967. Geology of the Caloola Syncline and Sturt’s Meadows Anticline. Unpublished B.Sc. thesis, University of N.S.W. THompson, B. P., 1962. Upper Precambrian Strati- graphy, Barrier Ranges, N.S.W. Unpublished report Dept. Mines, Sth. Aust. Soon to appear in Geology of N.S.W., Geol. Soc. Aust., in press, 1968. THompson, B. P., e al., 1964. Precambrian Rock Groups in the Adelaide Geosyncline: A New Subdivision. Geol. Surv. Sth. Aust. Quart. Geol. Notes, No. 9. VotsEY, A. H., 1959. Australian Geosynclines. J. Sci., 22, 189-198. Warp, C. R., 1967. Geology of the Fowler’s Gap- Nundooka District. Unpublished B.Sc. thesis, University of N.S.W. WooLnouGH, W.G., 1927. The Duricrust of Australia. J. Proc. Roy. Soc. N.S.W., 61, 24-53. WRIGHT-SmITH, C. N., 1967. Geology of the Fowler’s Gap Homestead District. Unpublished B.Sc. thesis, University of N.S.W. Geological Investigations in the Mem. Roy. Soc. Sth. Aust., Aust. (Received 3 October 1968) Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 73-81, 1969 Where Are the Electrons ?* Rk. D. BROowN When chemists come to interpret their observations in terms of the atomic molecular theory of matter one of the first questions to be settled is: where are the electrons? This may arise at a relatively elementary level in balancing a redox equation or using the octet rule to derive a structural formula. At more sophisticated levels of valency theory the interpretation of virtually all chemical and physical properties of compounds depends heavily on a knowledge of how the electrons are distributed over a molecule. This knowledge of the distribution of electrons being so basic to chemistry, it is instructive to consider how profound is this knowledge. There is much to suggest that chemists are fairly well informed on this matter. For example, many papers in the current literature contain confident pictures of electron distribu- tions in molecules (as portrayed by drawing in covalent bonds, charges on atoms, etc.) and of electronic shifts accompanying chemical reactions. Basic textbooks describe ionic and covalent bonds, and more advanced texts discuss bonds in transition element compounds with synergic back donation of z-electrons strengthening the metal ligand o-bond and simultaneously ameliorating its polarity. What is rarely pointed out is that all of these descrip- tions of electron distributions are based upon sets of rather sweeping assumptions, the validity of which is open to question. Indeed, when looked into closely it is surprising how little we know beyond reasonable doubt about where the electrons are in molecules. I propose to try to illustrate the current fight with ignorance and to do it at two levels. Firstly, I want to consider how much we know about the gross distribution of electrons when we merely try to assess the net charges that should be associated with each atom. Secondly, I want to consider to what extent we can distribute the atomic electron densities among the different atomic orbitals associated with each atomic nucleus. Thus at the first level I shall consider the * Liversidge Lecture delivered before the Royal Society of New South Wales, July 17th, 1968. overall distribution of electrons in formaldehyde and other molecules. At the second level I shall touch on questions such as: are the 3d orbitals of sulphur used to any appreciable extent to accommodate valence electrons in SF,? Let us start with the problem of gross charges. If we are interested in the charge distribution in formaldehyde, for example, a textbook is likely to indicate the electronic structure as shown in Fig. 1. We should first ask what this means. The only aspect of charge distribu- tion that is observable in principle is the total electron density at various points in space, |y?|; in practice only certain derived quantities that I shall mention later have been observed. H NS 5+ a 4 H Fic. 1—Typical textbook representa- tion of the charge distribution in formaldehyde. SE =e, (O) Very accurate, theoretical information is available for some diatomic hydrides (Bader et al., 1967), as shown in Fig. 2. To gain some impression of the changes that accompany bonding, it is useful to inspect the differences between these charge distributions and those for the separate uncharged atoms. Fig. 3 shows the difference maps. Fig. 4 shows an analysis into integrated charge transferred to bonding and to lone pair regions. We note that these data parallel our classical views that LiH is mainly ionic and that bonding becomes more and more covalent as we proceed across the periodic table. However, the appearance of the opposite ionic character, e.g. in HF, is hard to discern. One does not know just how this would reveal itself in the charge density contour maps—HF looks like the fluoride ion with a “ pimple ”’ representing the hydrogen. 74 R. D. BROWN OH "Nl, HF 'Z° Fic. 2—Total molecular charge density contours for the first-row diatomic hydrides (atomic units ; H nucleus is on the right in each case). The innermost contours encircling the heavy nucleus have been omitted for the sake of clarity. (Reproduced, with permission, from Bader eé al., 1967.) WHERE ARE THE ELECTRONS? 75 Fic. 3—Contour maps of the electron density difference (molecule—separate atoms) in atomic units for the first-row diatomic hydrides (H on right in each case). (Reproduced, with permission, from Bader e¢ al., 1967.) 76 R. D. BROWN In order to associate different portions of the integrated charge density with different atoms, we must have some agreed scheme of partitioning. One could perhaps imagine surfaces dividing up all space into regions and associating each region with one of the atoms, but this presents difficulties in deciding where to place the partitions. However, instead it has proved more convenient to construct approximations of | using sets of functions associated with each of the atoms. We have become accustomed to call these functions atomic orbitals. It is straightforward to dissect the approximate | /?| algebraically in a way that yields occupation numbers for each of the atomic orbitals, and if we add up the occupation numbers for all of the orbitals on a particular nucleus we obtain the electron density for that atom. I do not want to go into details about this analysis, but rather to make two points. y Region H ' ’ ' , \ . \ i / \ ) / \ ery a \ - Ne ee = Fic. 4—Definitions of A and B regions. Firstly, there is wide freedom in choosing the sets of atomic orbital functions used to represent and it is even permissible to go to the extreme of using functions centred on only one of the atomic nuclei. In the latter case one might deduce that all the electrons are on one atom ! The lesson to be learned is that the conclusion that we draw about electron distributions will depend to some extent on the kind of atomic orbitals that we decide to use to build up the molecular eigenfunction. Secondly, if we use only a relatively simple set of atomic orbitals to obtain an approximate the resultant analysis of electron distribution will be affected to some extent because we have not analysed — the exact wave function. Total Charge Migration in Diatomic Hydrides as Determined by Density Difference Maps* Charge Charge AH Increase in | Increase in Region A Region B LiH 0-01 0-55 BeH 0-11 0°35 BH 0-20 0-16 CH 0-20 0-16 NH a 0-20 0-16 OH of 0:22 0-19 HF 0-24 0:22 * These figures were obtained by numerical integration using a grid of 0:02 a.u. Regions A and B are defined in Figure above. Reproduced from jJ. Chem. Phys., 1967, 47, 3381, Fig. 2 (6) and Table 11. Let me now give you a survey of what some of the best available current wavefunctions for various small molecules have to say about charge distributions as analysed in terms of molecular orbitals, so that you can compare these with the popular mythology of textbooks. While I am doing this you may be asking how reliable are these wavefunctions, and later in this talk I shall point out some experimental data that can be used to test these wave- functions. First let us look at formaldehyde. The calculated electron distribution (Peters, 1963 ; Cook and McWeeny, 1968) is shown in Fig. 5. Notice that the qualitative tends to not agree with popular belief as represented in textbooks because the total carbon charge (—0-14) is more negative than the oxygen charge (—0-12). The overall polarity must be largely laid at the door of the positive net charges on the hydrogens, with an additional contribution from the atomic dipole of the oxygen. The carbonyl polarity is not that normally believed. It is possible that this is an artifact of the particular wavefunction used here, but several other recent approximate wavefunctions for formaldehyde display the same qualitative result. As a second example (Veillard ef al., 1967), let us consider the prototype of the so-called dative bond BH,<-NH, (Fig. 6). From com- WHERE ARE THE ELECTRONS? ui parison with analogous calculations on BH, and on NH, separately, we see an interesting electron drift accompanying the association of the parts, quite different to that deduced by octet rule methods. In particular, the net charge on the boron is virtually unchanged by bond formation and a rather curious alternating drift of electrons, involving the hydrogens attached to boron, has occurred. Somewhat similar distributions of electrons have been found in other saturated systems (Pople and Gordon, 1967). Thus when a fluorine substituent is introduced into a saturated hydrocarbon (Fig. 7) the immediate effect is to generate a net positive charge on the attached carbon, but the more distant influences seem to +0°13 -0-13 C+0-15 -0-13 -015O0 +0°13 H o-ORBITAL CHARGES - 0:03 +0-03 C O t-ORBITAL CHARGES TOTAL NET CHARGES Fig. 5—Charge distribution in formaldehyde (Peters, alternate in sign, not to fall monotonically ! It is possible that a new set of rules for o-electrons drifts will be called for in place of the beloved inductive shifts of organic chemistry. 0-285 - 0-10 H iH Net re 7 x COMPARE H = bB —— -0-008 +0-024 - 0-261 +0-087 BORAZANE CHARGES (DAUDEL ET. AL. 1967) Fic. 6—Charge distribution in borazane (Daudel et al., 67). Let me now turn to another example that has been of particular interest to us at Monash: that of non-alternant hydrocarbons. The interest centres largely around three conjugated cyclic hydrocarbons: fulvene (1), dimethylene- cyclobutene (2) and azulene (3): C,H Ge 6 6 10 8 All three hydrocarbons have a substantial dipole moment—of the order of ten times the magnitude of analogous aromatic hydrocarbons. We ask to what should the polarity be attributed. The initial proposal was that for conjugated hydrocarbons containing odd membered rings— so-called non-alternants—the distribution of m-electrons is non-uniform (Coulson and Rush- brooke, 1940), and this leads to the appreciable polarity. More recently it has been predicted (Brown and Burden, 1966), and then confirmed experimentally (Brown e al., 1967), that dimethylenecyclobutene, though an alternant, 73 R. D. BROWN should have an uneven distribution of z-electrons and so be polar. In attempting to account in more detail for the polarity, it has been suggested that the o-electrons also contribute to the polarity, particularly because the hydrogen atoms are appreciably charged. Let us see now what the best available wave functions imply, first with dimethylenecyclobutene (Fig. 8). Here the implication is that the polarity must be ascribed primarily to z-electrons, the total o-electron effect being a minor contribution. measurement on fulvene vapour by microwave methods and now find that the dipole moment is 0-44D. In the case of azulene, the story is still less satisfying. The theoretical computations again imply that the polarity stems essentially from a non-uniform z-electron distribution (Fig. 10) but the theoretical value of the moment is depressingly far from a recent precise experi- mental value for azulene vapour (Tobler e¢ al., 1965). Thus it is clear that the presently available electronic wavefunctions for molecules tal H -50/ H—C—H H 0 +22 A a A 5205 +187 Se / epee oe By ee NeZe ~189 -7 J +210 ~ Vf \ LS H F H H +52 os H rp mi =e N28 yf Yes / ee +201 H—C—C—F C= H—C ==cC —F ~157 ~136 +36 “a H +5 Fic. 7—Charge distribution in fluorocarbons (milliprotonic units). The agreement of the calculated value with the observed dipole moment is impressive. However, let us next turn to fulvene (Fig. 9). Here the qualitative story is similar to that of dimethylenecyclobutene, but the agreement with the experimental dipole moment data is less satisfactory. Hitherto the value, deduced from measurements in solution on substituted fulvene, was1-:1D. We have been engaged in a precision like azulene are not all that we would like; but perhaps the qualitative indication of the relative polarity contributions from o- and m-electrons are sound. Now let us move on to somewhat more complex systems involving larger atoms. First, a few words about SF,, PF;, etc. Textbooks will sometimes describe the bonding as involving sp3d? or spd hybrids on the central atom WHERE ARE THE ELECTRONS ? 79 these hybrids being used to form somewhat +24 polar covalent bonds with the fluorine ligands. Alternatively, a structure involving ionic- covalent resonance among the various ligand positions and only the s and p orbitals on the S (or P), has sometimes been advocated. On close analysis, it proves difficult to decide -44 (-37) whether the d-orbitals of the central atom are involved in the bonding because of the variety of functional forms that can be written down et +25 (+101) +27 FULVENE net charges (e/1000) 1 net charges in parentheses Dipole Moment o densities 0.260 D 1 « hybridization 0.086 He m densities 1.061 t +34 TOTAL Or6s7 Dt experiment: 0 44D Fic. 9—Fulvene. DIMETHYLENE CYCLOBUTENE net charges (e/1000) mt net charges in parentheses : , wee Another example involving a_ transition Dipole moment element atom is the electronic structure of the o densities 0.254D f permanganate ion. In recent years a number Ta cae a ees | of investigations of the electronic structure of mw densities OF OOK ; : ion n lished. The ne ee ee tetrahedral anions have been publishe experiment: 0.61, D Fic. 8—Dimethylenecyclobutene. as representing a d-orbital. However, if we agree that by orbitals we mean the various functions that are obtained by solving the H-atom problem so that Ssa=N.p*e/3.Y o,(0,0) (e=Gr/a) (Y.,: Spherical harmonic of order 2) then the best function that has so far been derived for these molecules (by Dr. Peel) implies (Table 1) that the 3d orbitals are insignificantly Sccupied in SF,, PF;, SF,, CIFs, etc. AZULENE NET CHARGES (e/1000) TABLE 1 a net charges in parentheses Orbital Occupation Numbers Dipole Moment 7 o density 0.809D—> o hybridization 0.589 — PF; SF, CIF; ¢ total 0.220 - | ae ey a ee aac: acer S : : J ove TOTAL 3,226 De 3p b 2-15 2-67 3-80 j a | 3d ek 0°13 0-22 0-19 experiment 0.79 D Fic. 10—Azulene. 80 most elaborate of these (Table 2), obtained by Mr. James at Monash, implies that the 4s and 4p orbitals of Mn are but little occupied, the central atom using its 3d orbitals almost exclusively to accommodate valence electrons. TABLE 2 Orbital Occupation Numbers MnO4 CrO4, MCZDO CNDO MCZDO CNDO 3d 5-70 6°71 5+ 84 6-56 4s 0-08 0-10 0-04 0-10 4p 0-00 0-02 0-00 0-15 These calculations on systems containing larger atoms are necessarily rather less rigorous than those on smaller systems and it is possible that the picture could be changed somewhat by still more elaborate calculations. However, it seems unlikely that the qualitative description will be noticeably altered. The overall picture that we are left with is one rather different from the classical description in current textbooks. Returning now to smaller systems, let us consider what kind of experimental tests can usefully be applied to molecular wavefunctions. Because of the widespread use of the variation theorem for computing wavefunctions, a habit of mind has grown of asking what kind of energy expectation value derives from the function v. LEy=b |# | OK The more negative «E> is the better function is considered to be. However, the energy test depends critically on how well y accounts for electron correlation. If we are interested in electron distribution this correlation effect is less important and so functions that give only moderate values of can sometimes give a good picture of the overall electron distribution Rk. D. BROWN in the molecule. It therefore seems better to apply different tests, namely the following : = av | d>/ derived from dipole moment. : 3°2+0-3 x 10716 cm.? Gib 5-2+0-3 x 10-71% cm.? Kee 11°-4+0-3 x 10-16 cm.? TABLE 4 Experimental Values (A.U.)_ of Various Electronic Properties of Formaldehyde Jzz(O) = 0-703 qyy(O) — 1-687 7% COS 19-495 ba 11-3 wa 13-7 oe 40°8 Zo|r?o 1-261 Zc|r>c 1-262 Jaa(D) — 1-446 qag(D) — 0-178 qee(D) 0-650 Op/7*p 2-059 Bp/r?p 0-266 1/7 6-12 WHERE ARE THE ELECTRONS? 81 provide a very stringent test of electronic wavefunctions and so far even the best pub- lished wavefunctions for formaldehyde show deficiencies. However, further experimental work of this kind and further computational effort on wavefunctions must surely produce a steady increase in our knowledge of how the electrons are distributed in molecules. Maybe if you are kind enough to invite me again to Sydney some years hence to talk on “Where Are the Electrons ? ’”’ I may be able to give you more confident answers such as text- books now give. At present the honest answer is: ‘‘ We do not know for sure but we have some suspicions ! ”’ (Delivered on References Baver, R. F. W., KEAveNny, I., AND CADE, P. E., 1967. J. Chem. Phys., 47, 3381. Brown, R. D., AND BurRDEN, F. R., 1966. Comm., 448. Brown, R. D., BuRDEN, F. R., JONEs, A. J., AND KENT, J. E., 1967. Chem. Comm., 808. Cook, D. B., anpD McWEENYy, R., 1968. Chem. Phys. Letteys, 1, 588. CouLson, C. A., AND RUSHBROOKE, G. S., 1940. Camb. Phil. Soc., 36, 192. HUtTTNER, W., Lo, M. K., AnD FLYGARE, W. H., 1968. J. Chem. Phys., 48, 1206. PETERS, D., 1963. J. Chem. Soc., 4017. PopPLeE, J. A., AND GorDON, M., 1967. J. Amer. Chem. Soc., 89, 4253. ToBLeR, H. J., BAuDER, A., AND GUNTHARD, H. H., 1965. J. Molec. Specty., 18, 239. VEILLARD, A., LEvy, B., DAUDEL, R., AND GALLAIS, F., 1967. Theoret. chim. Acta, 8, 312. Chem. Proc. 17 July 1968) 1 a _ co eee 84 A. KEANE Let R be the total resistance of the intake, so that 7 is the resistance per unit length and R=rL. If g is the conductance of the barrier per unit length of airway, then the total con- ductance of the barrieris G=gL. (Conductance is the inverse of resistance). In this model we have not only neglected the irregularities of the mine but also the change of air density due to pressure and temperature. The effect of pressure changes is not very important, but temperature changes are large and could be important. 3. Simple Solution of the Model Now we have a model and can begin to attempt a mathematical solution. If the quantity of air entering the mine per second is Q, and the quantity reaching the face is Q,, then Q).—(Q,; is lost through the goaf and ibis is the average quantity flowing through the airways. Working with averages, the equation for flow in the airways is: 2 P, = R( su Or and since the average pressure difference between the airways is Po, the flow through the goat is given by (Qo—Qr) =GP. If instead of turbulent flow in the airways we assumed streamlined flow so that _p(%t9r raf then Pia ok (08-02) Qo/Qr=1 “KG. 4. A More Sophisticated Solution The use of averages is not the approach of the applied mathematician. He will set up the equations in terms of the differential calculus, which gives Cie . Sead, rQ dQ lager for flow through minute lengths of airway and minute widths of barrier, remembering that the pressure difference between the airways 1s 2P. The solution of these equations gives relations between the pressure and quantity of air at any point of the airways (Peascod and Keane, 1955 ; Keane, 1956). Since rL=R and gL=G, we find that R P=} = (0-03) and where k= Q-/ Qo. and F is the hypergeometric function. If the flow in the airways were assumed streamlined, then the equations would reduce to dP dQ a0 =rQ and a ope, which gives the solutions Aes 2 2 P= (0?—Q2) and Qo=Q, cosh 24/RG. — These equations show that the use of averages in the previous section underestimates the leakage loss. 5. Improvements to the Model We should now look closer at the assumptions of our model to see if it can be improved. The square law holds for fully turbulent flow, while the linear law holds for streamlined flow. In the airways it seems reasonable to assume that the flow lies somewhere between these two limits and a more realistic equation would be P=RQ” where 1 p.r. 2 Montreal Avenue, Killara (1960). *QUODLING, Florrie Mabel, Ph.D., B.Sc., 145 Midson Road, Epping (1935: P5). RavE, Janis, M.Sc., Consulting Geologist, Box 5440C, G.P.O., Melbourne (1953: P6). Ramm, Eric John, Experimental Officer, Australian Atomic Energy Commission, Lucas Heights (1959). RaATTIGAN, John Herbert, Ph.D., M.Sc. (1966: P2). *RAYNER, Jack Maxwell, O.B.E., B.Sc., 5 Tennyson Crescent, Forrest, Canberra, A.C.T. (1931: Pl). Reap, Harold Walter, B.Sc., 1/29 Spinks Road, Corrimal (1962: P1). REICHEL, Alex, Ph.D., M.Sc., Department of Applied Mathematics, University of Sydney (1957: P4). Rice, Thomas Denis, B.Sc., 24 Alliott Street, Camp- belltown (1964). RicgBy, John Francis, B.Sc.(Melb.) (1963). Riaes, Noel Victor, B.Sc.(Adel.), Ph.D.(Cantab.), F.R.A.C.I., Associate Professor of Organic Chemistry, University of New England, Armidale (1961). RitcHig£, Arthur Sinclair, M.Sc., Associate Professor of Geology, University of Newcastle (1947: P2). Ritchie, Ernest, D.Sc, b-A.A., Chemistry Depart- ment, University of Sydney (1939: P19). 106 MEMBERS OF THE SOCIETY RoBBINS, Elizabeth Marie (Mrs.), M.Sc., Waterloo Road, North Ryde (1939: P38). RoBeErts, Herbert Gordon, B.Sc., c/o Anaconda Aust., Inc., 34 Hunter Street, Sydney (1957). RoBeErts, John, Ph.D., Bureau of Mineral Resources, Geology and Geophysics, Box 378, Canberra City, AC T1961 Ps): ROBERTSON, William Humphrey, B.Sc., c/o Sydney Observatory, Sydney (1949: P28). Ropinson, David Hugh, A.S.T.C., Chemist, 12 Robert Road, West Pennant Hills (1951). Roper, Geoffrey Harold, M.Sc., Ph.D., Associate Professor, School of Chemical Engineering, University of New South Wales (1966). ROSENBAUM, Sidney, 5 Eton Road, Lindfield (1940). ROSENTHAL-SCHNEIDER, Ilse, Ph.D., 48 Cambridge Avenue, Vaucluse (1948). Ross, Victoria (Mrs.), M.Sc., B.Sc.(Hons.), ‘“‘ Merroo ’’, Mill Road, Kurrajong (1960). ROUNTREE, Phyllis Margaret, D.Sc., Royal Prince Alfred Hospital, Sydney (1945). RoyLeE, Harold George, M.B., B.S.(Syd.), 161 Rusden Street, Armidale (1961). SAPPAL, Krishna Kumar, M.Sc., Department of Geology, Nagpur, India (1966). *SCAMMELL, Rupert Boswood, B.Sc., 10 Buena Vista Avenue, Clifton Gardens (1920). Geologist, c/o Nagpur University, SCHOLER, Harry Albert Theodore; M.Eng:,’ Civil Engineer, c/o Harbours and Rivers Branch, Pubhe Works Department, N.S: W.,” Phillip Street, Sydney (1960). scott, John Alan Belmore, BSc.(Old:), 193 Forest Road, Kirrawee (1964). SEE, Graeme Thomas, B.Sc., School of Nuclear Chemistry, University of New South Wales, Kensington (1949). SELBY, Edmond Jacob, P.O. Box 121, North Ryde (1933). *SHARP, Kenneth Raeburn, B.Sc., Engineering Geology Branch, Snowy Mountains Authority, North Cooma (1948). SHAW, Stirling Edward, B.Sc.(Hons.), Ph.D., F.G.A.A., School of Earth Sciences, Macquarie University, North Ryde (1966). SHERRARD, Kathleen Margaret (Mrs.), M.Sc., 43 Robertson Road, Centennial Park (1936: P6). SHERWIN, Lawrence, B.Sc.(Hons.)(Syd.), 186 Sylvania Road, Miranda (1967). Simmons, Lewis Michael, Ph.D., The Scots College, Victoria Road, Bellevue Hill (1945: P3). Sims, Kenneth Patrick, B.Sc., 25 Fitzpatrick Avenue East, French’s Forest (1950: P14). SLADE, George Hermon, B.Sc:, W. Hermon, Slade '& Co. Pty. Ltd., Mandemar Avenue, Homebush (1933). SLADE, Milton John, B.Sc., Dip.Ed.(Syd.), M.Sc.(N.E.), 162 Donnelly Street, Armidale (1952). Smith, «Ann Ruth (Mrs.), B.Sc.) Box 134 PO" Queenstown, Tas. (1959). SMITH, Glennie Forbes, B.Sc., Box 134, P.O., Queens- town, Tas. (1962). SMITH! William) (Eric, “PhD: (N-S.W:), IM Sc:(Syd)) B.Sc.(Oxon.), Associate Professor. of Applied Mathematics, University of New South Wales, Kensington (1963: P1). SMITH-WHITE, William Broderick, M.A., Associate Professor of Mathematics, University of Sydney (1947: P4; President 1962). SouTtH, Stanley Arthur, B.Sc., Geologist, 47 Miowera Road, Turramurra (1967). STANTON, Richard Limon, Ph.D., Associate Professor of Geology, University of New England, Armidale (1949: P2). STAPLEDON, David Hiley, B.Sc., 61 Francis Street, Brighton, South Australia (1954). STEPHENS, James Norrington, M.A.(Cantab.), Ph.D., 170 Broker’s Road, Mt. Pleasant, Wollongong (1959). STEVENS, Eric Leslie, B.Sc., Senior Analyst, Depart- ment of Mines, N.S.W.; p.r. Lot 17, Chaseling Avenue, Springwood (1963). STEVENS, Neville Cecil, Ph.D., Geology Department, University of Queensland, St. Lucia, Brisbane (1948: P85). STEVENSON, Barrie Stirling, B.E. (Mech. and Elec.) (Syd.), 21 Glendower Street, Eastwood (1964). Stock, Alexander, D.Phil, Ph.D) = Professor of Zoology, University of New England, Armidale (1961). STOKES, Robert Harold, Ph.Ds Diseaweoe a, Ae Garibaldi Street, Armidale (1961). STRUSZ, Desmond Leslie, Ph.D., B.Sc., Bureau of Mineral Resources, Geology and Geophysics, Canberra, A.C.T. (19602) 2a) STUNTzZ, John, B.Sc., 11 Jackson Crescent, Pennant Hills (1951). SuRRY, Charles (1961). SUTERS, Ralph William, B.Sc.(N.S.W.), Science Master, Berkeley High School; p.r. 49 Walang Avenue, Figtree (1968). SWANSON, Thomas Baikie, M.Sc., Technical Service Department, I.C.1.A.N.Z., 0 Box WSPiaAGeR. Oo: Melbourne (1941: P2). SWINBOURNE, Ellice Simmons, Ph.D., 30 Ellalong Road, Cremorne (1948). TAyYLor, Nathaniel Wesley, M.Sc.(Syd.), Ph.D.(N.E.), Department of Mathematics, University of New England, Armidale (1961). THEW, Raymond Farly, 88 Wahroonga (1955). Tuomas, Penrhyn Francis, “AiS.1.C,)"Optometrisi Suite 22, 3rd Floor, 29 Market Street, Sydney. (1952). THomson, David John, B.Sc., Geologist, 61 The Bulwark, Castlecrag (1956). THomSON, Vivian Endel, B.Sc., 1/171-177 Rokeby Road, Howrah, Tas. (1960). THompson, Don Gregory, B.Sc., Dip.Ed., Master, R.A.N. College, Jervis Bay (1967); THWAITE, Eric Graham, B.Sc., 8 Allars Street, West Ryde (1962). TICHAUER, Erwin R., D.Sc.(Tech.), Dipl.Ing., Research Professor of Biomechanics, New York University Medical Center, 400 East 34th Street, New York, N.Y; US ALS (1960); TILLey, Philip Damien, B.A.,-Dr. Phil: Departmens of Geography, University of Sydney (1967). TOMPKINS, Denis Keith, Ph.D., M.Sc., 14 Warrowa Road, Pymble (1954: Pl). Braeside Street, UpFoLp, Robert William, B.E., M.E., Department of Engineering, Wollongong University College, Wollongong (1968). VALLANCE, Thomas George, Ph.D., Associate Pro- fessor, Department of Geology and Geophysics, University of Sydney (1949: P38). VAN BRAKEL, Albertus Theodorus, B.Sc.(Hons.), Geologist, 7 Bruce Street, Glendale (1968). MEMBERS OF THE SOCIETY 107 Van Dijk, Dirk Cornelius, D.Sc.Agr., c/o C.S.I.R.O., Division of Soils, Cunningham Laboratory, St. Lucia, Queensland (1958). VEEVERS, John James, Ph.D., School of Earth Sciences, Macquarie University, North Ryde (1953). VERNON, Ronald Holden, Ph.D., M.Sc., School of Earth Sciences, Macquarie University, North Ryde (1958: Pl). WICKERY, Joyce Winifred, M.B.E., D.Sc., 17 The Promenade, Cheltenham (1935). VoisEy, Alan Heywood, D.Sc., Professor of Geology and Head of the School of Earth Sciences, Macquarie University, North Ryde (1933: P13; President 1966). *VONWILLER, Oscar U., B.Sc., Emeritus Professor, “ Rathkells ’’, Kangaroo Valley, N.S.W. (1903: P10; President 1940). WALKER, Donald Francis, Surveyor, 13 Beauchamp Avenue, Chatswood (1948). *WaLkoM, Arthur Bache, D.Sc., 5/521 Pacific Highway, Killara (1919 and previous membership 1910-1913: P2; President 1943). Warp, Colin Rex, B.Sc.(Hons.), Geologist, 42 Daunt Avenue, Matraville (1968). WarD, Judith (Mrs.), B.Sc., 16 Mortimer Avenue, Newtown, Hobart, Tas. (1948). *WARDLAW, Hy. Sloane Halcro, D.Sc., 71 McIntosh Street, Gordon (1913: P5; President 1939). WARRIS, Bevan Jon, B.Sc., c/o ESSO Exploration, Box 4049, G.P.O., Sydney (1967). Wass, Robin Edgar, Ph.D.(Syd.), B.Sc.(Hons.)(Qld.), Department of Geology and Geophysics, Uni- versity of Sydney (1965: Pl). *WATERHOUSE, Lionel Lawry, B.E.(Syd.), 42 Archer Street, Chatswood (1919: Pl). *\WATERHOUSE, Walter L., C.M.G., M.C., D.Sc.Agr., F.A.A., 30 Chelmsford Avenue, Lindfield (1919: P7; President 1937). SVATTON, Edward Charlton, Ph.D., B.Sc.(Hons.), A.S.T.C., 47 Centennial Avenue, Lane Cove (1963). WEBBY, Barry Deane, Ph.D., M.Sc., Department of Geology and Geophysics, University of Sydney (1966). West, Norman William, B.Sc., c/o Department of Main Roads, Sydney; p.r. 9/62 Murdoch Street, Cremorne (1954). WESTHEIMER, Gerald, Ph.D., Professor of Optometry University of California, Berkeley 4, California, U.S.A. (1949). WHEELHOUSE, Frances, Senior Laboratory Tech- nician, School of Biological Sciences, University of New South Wales, Kensington (1968). WHITLEY, Alice, M.B.E., Ph.D., 39 Belmore Road, Burwood (1951). WHITLEY, Gilbert Percy, F.R.Z.S., Honorary Associate of the Australian Museum, College Street, Sydney (1963). WHITWORTH, Horace Francis, M.Sc., 31 Sunnyside Crescent, Castlecrag (1951: P4). WILKINS, Coleridge Anthony, Ph.D., M.Sc., Depart- ment of Mathematics, Wollongong University College, Wollongong (1960: P2). WILKINSON, John Frederick George, M.Sc.(Qld.), Ph.D.(Cantab.), Associate Professor of Geology, University of New England, Armidale (1961: P1). WILLIAMS, Benjamin, 12 Cooke Way, Epping (1949). WILLIAMSON, William MHarold, M.Sc., 6 Hughes Avenue, Ermington (1949: PL). WILson, Christopher John Lascelles, B.Sc., Depart- ment of Geophysics and Geochemistry, Australian National University (1967: P1). WINCH, Denis Edwin, Ph.D., M.Sc., Senior Lecturer in Applied Mathematics, University of Sydney (1968). Woop, Clive Charles, Ph.D., B.Sc. (1954). Woop, Harley Weston, D.Sc., M.Sc., Government Astronomer, Sydney Observatory, Sydney (1936 : P16; President 1949). WopPFNER, Helmut, Ph.D., Supervising Geologist, ».A. Geological Survey, S.A. Department of Mines, Box 38, Rundle Street P.O., Adelaide, S.A. (1966: Pl); WriGcHT, Anthony James, Ph.D., B.Sc., Department of Geology, Victoria University of Wellington, Wellington, N.Z. (1961). Wyrm, iKussell George, Ph.D. NSc,, Physicce National Standards Laboratory, University Grounds, City Road, Chippendale (1960). YEATES, Neil Tolmie McRae, D.Sc.Agr.(Qld.), Ph.D.(Cantab.), Associate Professor of Livestock Husbandry, University of New England, Armidale (1961). Associates Cottins, Angus Robert, 16 Hull Road, Beecroft (1965). DENTON, Norma (Mrs.), Bunarba Road, Miranda (1959). DoNnEGAN, Elizabeth (Mrs.), 18 Hillview Street, Sans Souci (1956). Emery, Hilary May Myvanwy (Mrs.), ‘‘ The Wheel- house ’’, Erobin, Queensland (1965). GRIFFITH, Elsie A. Caringbah (1956). _ GUNTHORPE, Robert John, B.Sc.(Hons.), Department | of Geology, University of New England, Armidale (1965). (Mrs.), 9 Kanoona Street, ILEAVER, Harry, B:A., Bic), MCS.) Ch.M.. MERC OixG., F.G.S., 30 Ingalara Avenue, Wahroonga (1962). LE FEvRE, Catherine Gunn, D.Sc.(Lond.), 6 Aubrey Road, Northbridge (1961). McCLymMont, Vivienne Cathryn, B.Sc., Handel Street, Armidale (1961). STANTON, Alison Amalie (Mrs.), B.A., 35 Faulkner Street, Armidale (1961). STOKES, Jean Mary (Mrs.), M.Sc., 45 Garibaldi Street, Armidale (1961). Witrey,. Helen) Ann (vrs. )) 13.Se.,. Department. of Geology, University of New England, Armidale (1965). 108 MEMBERS OF THE SOCIETY Obituary 1966-67 1967-68 Sir Neil Hamilton FAIRLEY, an Honorary Member Lord FLOREY, O.M., F.R.S., an Honorary Member since 1952. since 1949. Thelma I. CHRISTIE (1953). Edward W. ESDAILE (1908). Edward J. KENNY (1924). Edward Gordon MANCHESTER (1965). Stephen L. LEACH (1936). Frank R. MORRISON (1922). Henry J. MELDRUM (1912). Patrick F. D. MURRAY (1950). Archibald B. B. RANCLAUD (1919). Arthur Spencer WATTS (1919). AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. 71-79 ARUNDEL ST., GLEBE, SYDNEY, N.S.W., 2037 Uy é Hs EXcELLENCY THE Governor OF New ‘SouTa Wares SIR. RODEN CUTLER, VGoy K. Cc. M.G.. C.B.E. President’ 2 ey ik: : Solas “Vice-Presidents ALAN A. D Weha) <6 WS H. c. POGGENDORFF, B.Se.Aer. R Ww. Le FEVRE, bse PRS, oe oe ‘A VOISEY, p.sex ae = a ss jae "Honorary Secretaries eg E a wen iS A. REICHEL, PRD., | ‘M.Sc. ve - Honorary Rreadihcr Be Oe ee a oer — - i F, CONAGHAN, M.Sc. oe Se oe Bie a S "Members of Council: eat ee (es iS Peas 3 C CAMERON, M. A.B. Sc. (ean) 1 D.C. a Vide Le G. NEUHAUS, Msc, a -GRIFFIN, Bisc. 5s oo - J. P. POLLARD, pip.app.chem. 2 % ee “£, KITAMURA, B.A, ce Ser eee M.J. PUTTOCK, B.Sc. (Eng.), A.Inst.P, eee Ve Bit Guie B.Sc, crad, Dip. W~ HL ROBERTSON, mga RS v) ee & y ae SS ne a ete =. ¥ x 2 Se se Sa ae Ta Any J ‘ = a ay re pete roe pie Ma Re ' % ; Hie Ret aa \ = 7 * - — e, 5 rt Ai Be ! shy % 7) a2 we ‘ " nok ot 1 \ ~< 2 S + { — cs after an interval of inactivity it ‘was resuscitated in 1850 under the name of the losophical Society ”, by which title it was known until 1856, when the name was ae ‘* Philosophical. Society. of New South Wales”, In 1866, by the sanction of Her i Parli iment of New he ae in 1881. ee BE, ea a ee fi nes i S Has pa eed Sy * es eS a ‘ i t - == \ es \ ; 3 en f 4h = ‘o wei 70402 18 55 03-882 —05 23 34-14 911 May 30:°67177 18 54 11-525 —05 21 51-59 —0:022 —4-17 R 912 May 30-67177 18 54 11-493 —05 2) 51-86 913 June 03 - 66882 18 52 06-194 —05 20 22-48 +0:008 —4-18 S 914 June 03 - 66882 18 52 06-220 —05 20 21-87 915 June 19-61214 18 40 06-456 —05 44 10-23 —0:007 —4-12 R 916 June 19-61214 18 40 06-432 —05 44 09-98 917 June 24-60790 18 35 25-628 —06 02 14-58 +0:032 —4-08 W 918 June 24-60790 18 35 25-643 —06 02 14-22 919 July 03:57483 18 26 32-540 —06 47 28:81 +0:025 —3:98 §S 920 July 03: 57483 18 26 32-493 —06 47 28-79 921 July 15-53367 18 15 02-013 —08 10 16-98 +0:024 —3-79 W 922 July 15: 53367 18 15 02-052 —08 10 16-55 923 July 24-51005 18 O7 43-206 —09 25 10-08 +0:042 —3:62 R 924 July 24-51005 18 O7 43-242 —09 25 11-00 925 July 29-48561 18 04 27-434 —10 09 49-46 +0:014 —33-51 §S 926 July 29-48561 18 04 27-418 —10 09 49-38 927 Aug. 09- 44627 17 59 45-464 —ll 52 05-05 —0:003 —3-27 R 928 - Aug. 09 - 44627 17 59 45-510 —ll 52 05-38 929 Aug. 22-41169 17 59 03-630 —13 53 09-25 +0:001 —2-98 R 930 Aug. 22-41169 17 59 03-624 —13 53 09-92 931 Aug. 30-41567 18 O1 19-662 —15 04 47-07 +0:078 —2-83 S 932 Aug. 30-41567 18 O1 19-682 —15 04 47-15 933 Sept. 11-36921 18 08 20-700 —16 43 49-58 +0:020 —2°56 R 934 Sept. 11-36921 18 08 20-764 —16 43 48-64 112 W. H. ROBERTSON TABLE I—continued R.A, Dec Parallax No. (1950-0) (1950-0) Factors m Ss 2 4 of s ” 7 Iris 1968 U.T. 935 April 22 -68299 16 21 25-774 —24 41 20-10 +0:021 —1-67 W 936 April 22 -68299 16 21 25-750 —24 41 20-00 937 April 30: 64938 16 15 50-691 —24 22 56-66 —0:006 —1-42 R 938 April 30- 64938 16 15 50-686 —24 22 57-08 939 May 20-59368 15 57 09-901 —23 11 42-30 +0:034 —1-:60 W 940 May 20- 59368 15 57 09-840 —23 11 42-30 941 May 30-54969 15 47 02-630 —22 26 03-06 +0:002 —1-71 R 942 May 30: 54969 15 47 02-550 —22 26 03-14 943 June 03 - 53929 15 43 10-086 —22 06 59-80 +0:012 —1-76 §S 944 June 03 - 53929 15 43 10-092 —22 06 59-50 945 June 20- 48362 15 29 29-900 —20 49 29-07 +0:013 —1:96 R 946 June 20- 48362 15 29 29-870 —20 49 28-72 947 June 24-47870 15 27 09-196 —20 33 28-14 +0:038 —1:99 S 948 June 24-47870 15 27 09-203 —20 33 28-02 949 July 12-41190 15 21 38-552 —19 39 51-58 —0:008 —2-:12 R 950 July 12-41190 15 21 38-486 —19 39 51-12 951 July 16-41015 15 21 32-744 —19 32 27-20 +0:023 —2-14 W 952 July 16-41015 VA hemes yao r hls} —19 32 27-34 953 July 24-39569 15 22 32-964 —19 22 43-12 +0:022 —2:16 S$ 954 July 24-39569 15 22 32-989 —19 22 42-79 955 Aug. 01-37326 15 25 04-420 —19 19 26-46 +0:037 —2-:18 W 956 Aug. 01-37326 15 25 04-360 —19 19 25-82 39 Laetitia 1968 U.T. ‘057 April 30:77887 19 24 37-960 —10 17 42-44 —0:009 —3-67 R ‘958 April 30-77887 19 24 37-983 —10 17 42-57 ‘959 May 09-77129 19 27 47-631 —09 45 35-50 +0:037 —3:57 S$ ‘960 May 09-77129 19 27 47-684 —09 45 35-00 ‘961 May 29 -69810 19° °-28.°-03: 710 —08 54 32-11 —0:021 —3-69 R 962 May 29-69810 19 28 03-672 —08 54 32-14 963 June 19- 63763 19 18 13-594 —08 48 18-38 —0:010 —3-70 R 964 June 19- 63763 19 18 13-586 —08 48 18-74 965 June 24- 63458 19 14 36-540 —08 55 44-95 +0-:031 —3:69 W 966 June 24-63458 19 14 36-539 —08 55 44-72 967 July 03-59619 19 O7 21-450 —09 17 59-82 +0:004 —3-63 S$ 968 July 03-59619 19 O07 21-430 —09 17 59-79 969 July 15- 55860 18 57 09-041 —10 03 49-23 +0°010 —3:53 W 970 July 15: 55860 18 57 09-075 —10 03 49-55 971 July 24-52893 18 50 00-116 —10 47 50:10 +0:010 —3-42 R 972 July 24 - 52893 18 50 00-082 —10 47 50:82 973 Aug. 02-48202 18 44 02-635 —ll 37 19-26 —0:056 —3-31 R 974 Aug. 02- 48202 18 44 02-688 —ll 37 19-28 975 Aug. 22-43637 18 37 18-004 —13 34 18:30 —0:004 —3-:03 R 976 Aug. 22-43637 18 37 18-030 —13 34 18-27 977 Aug. 30: 43493 18 37 33-342 —14 19 837-74 +0:060 —2:93 S$ 978 Aug. 30° 43493 18 37 33-250 —14 19 87-92 979 Sept. 11-39343 18 41 08-698 —15 21 58-04 +0:024 —2-77 R 980 Sepe- 11-39343 18 41 08-552 —15 21 58:78 981 Sept. 16-37527 18 43 42-656 —15 45 26-22 +0:004 —2-:71 R 982 Sept. 16-37527 18 43 42-586 —15 45 26-12 433 Eros 1968 U.T. 983 April 01-52752 11 09 20-781 —38 50 58-35 +0-038 +0:80 R 984 April 01-52752 11 09 20-746 —38 50 57-66 985 April 08 - 49974 11 06 11-779 —37 19 27-00 +0:-012 +0:64 5S 986 April 08- 49974 11 06 11-710 —37 19 28-00 987 April 22-47356 11 09 34-680 —33 39 02-45 +0:048 0:00 S 988 April 22-47356 11 09 34-610 —33 39 03-00 989 April 2346723 11 10 15-082 —33 22 58-68 +0:032 —0:04 R 990 April 23 -46723 11 10 15-004 —33 22 59-95 PRECISE OBSERVATIONS OF MINOR PLANETS 113 TABLE I—continued R.A, Dec. Parallax No. (1950-0) (1950-0) Factors m Ss ° / Ww S wu 433 Eros—continued 991 May 03 - 44830 11 19 38-694 —30 48 10-60 +0:038 —0-44 S 992 May 03- 44830 ll 19 38-739 —30 48 10-18 993 May 06 - 43002 ll 23 16-052 —30 05 31-94 —0:007 —0:57 R 994 May 06 - 43002 11 23 16-000 —30 05 31-84 TABLE II No. Star Depend. R.A. Dec. No. Star Depend. R.A Dec 813 5521 0- 362834 28-785 36-92 830 5441 0: 426363 16-851 08°77 5563 0: 357603 39-437 15-08 5454 0: 303059 14-412 57-07 5543 0: 279563 28-978 41-35 . 5488 0-270578 02-275 28°33 814 5517 0: 448661 54-714 33-32 831 5395 0- 387552 56° 650 31-38 5547 0:321478 12-152 50-02 5411 0: 180678 33-916 00-88 5582 0- 229860 25-925 59-53 5426 0-431770 35-181 04-54 815 5543 0:345773 28-978 41-35 832 5394 0-331762 46-967 19-02 5593 0- 233701 27-260 11-38 5399 0: 277458 28-039 46-99 5547 0- 420526 12-152 50-02 5433 0: 390780 03-093 01-98 816 5534 0- 524226 23-194 39-06 833 5371 0-318654 11-986 52:78 5563 0: 249798 39-437 15-08 5394 0-338596 46-976 19-02 5582 0: 225976 25-925 59-53 5403 0-342749 56-994 31-16 817 5556 0- 268040 50-653 41-64 834 5362 0: 356620 34-219 45-70 5615 0- 229170 18-482 01-12 5399 0: 240794 28-039 46-99 5569 0: 502790 18-984 09-92 5409 0- 402586 15-282 03-11 818 5541 0: 257780 28-232 09-69 835 5285 0:269911 29-781 04-37 5568 0-347107 17:°527 10-36 5315 0: 215570 31-498 17-83 5597 0:395113 03-052 56-30 5312 0:514519 37-015 59-47 819 5556 0- 235034 50-653 41-64 836 5281 0- 404270 22-834 14-23 5541 0- 246591 28-232 09-69 5331 0- 251602 40-154 44-65 5585 0-518375 28-923 29-10 5306 0: 344128 58°775 11-40 820 5549 0: 297354 31-973 32-69 837 5295 0-335904 56-201 06-20 5597 0- 280777 03-052 56-30 5313 0- 405987 38-041 03-82 5568 0:421869 17-527 10-36 5320 0-258110 56-328 00-22 821 5556 0: 342070 50-653 41-64 838 5292 0: 404903 22-652 35-25 5595 0:340074 52-024 39-59 5315 0- 332500 58-797 11-37 5541 0-317856 28-232 09-69 5326 0: 262597 02-518 38-70 822 5534 0- 300426 23-194 39-06 839 5302 0: 220162 08-480 12-54 5585 0: 361675 28-923 29-10 5312 0-378813 37-015 59-46 5561 0-337899 33-334 40-24 5326 0-401025 02-518 38-71 823 5529 0- 301096 23-300 42-23 840 5292 0: 267828 22-653 35-25 5540 0-448970 00-007 07-72 5310 0- 347030 28-441 57-38 5541 0: 249934 28-232 09-69 5331 0:385142 40-154 44-65 824 5522 0-333278 34-949 51-66 841 5321 0: 345928 06-706 05-27 5556 0-429128 50-653 41-64 5326 0- 338082 02-518 38-70 5534 0- 237594 23-195 39-06 5356 0-315990 23-778 40:80 825 5504 0- 261232 38-540 30-64 842 5320 0- 273410 56:327 00-23 5524 0: 404840 11-046 33-86 5325 0- 294460 01-044 12-77 5529 0-333928 23-300 42-23 5349 0- 432130 39-406 34-23 826 5499 0-379692 50-902 27-11 843 5646 0: 402986 14-162 25°53 5536 0- 246502 37-839 01-17 5677 0-219381 50-024 44°57 5517 0-373806 54:714 33°33 5680 0-377633 29-436 49-74 827 5488 0: 468630 02-275 28-33 844 5381 0-379346 18-082 00-39 5503 0-208141 33-516 55-65 5670 0-385071 17-542 25-66 5507 0-323229 55-260 37-83 5685 0: 235583 08-963 35-40 828 5491 0: 485070 48-225 32-32 845 5713 0: 252844 07-044 23-47 5494 0-151433 05-102 59-65 5733 0:414797 10-381 31-34 5505 0: 363497 37-942 49-09 5746 0:332359 24-680 22-77 829 5444 0-525642 08-378 25-95 846 5719 0-343150 22-690 40:17 5468 0: 231108 48-883 26-14 5723 0:375746 55-591 07-44 5475 0: 243250 18-301 54-94 5753 0: 281104 06: 748 43-57 114 W. H. ROBERTSON TABLE II—continued No. Star Depend. RvAS Dec. No. Star Depend. R.A. Dec. 847 7505 0:337836 26-657 31-88 869 3755 0-372320 20-898 29-62 7514 0- 210432 11-612 35-72 3759 0- 280362 11-099 17-89 7540 0-451732 54-978 34-18 3767 0-347318 51-903 06-54 848 7504 0-332402 08-694 58-12 870 3751 0:459731 40-585 36-58 7530 0: 186468 25-597 04-01 3762 0-219900 05-911 49-11 7536 0:481130 00-857 27-20 3772 0-320369 38-229 04-14 849 7539 0-221648 13-152 58-63 871 3720 0-229014 55-491 39-18 7544 0-523231 31-064 32-33 3735 0-477335 11-979 49-89 7551 0-255121 45-067 53°27 4954 0-293651 30-039 37-73 850 7527 0- 303636 46-753 15-56 872 3717 0:338688 53-245 56-34 7550 0-345096 28-683 48-49 3739 0-302758 28-980 01-82 7554 0°351267 15-041 57-81 4958 0-358554 28-238 01-66 851 7355 0:435764 54-173 49-92 873 4910 0-313044 16-764 11-05 7356 0- 273850 56-374 44-43 4919 0-420399 35-928 02-85 7374 0: 290386 28-550 35-70 4931 0: 266557 55-508 39°35 852 7342 0-272108 53-572 32-64 874 4902 0-377086 08-638 39-99 7362 0:431200 25-791 02-22 4926 0-270494 01-571 27-73 7372 0- 296692 04-694 50-05 3717 0-352419 53-245 56-34 853 7295 0: 220344 32-830 44-74 875 4871 0-321511 33-444 08-23 7321 0:513860 58-369 04-80 4873 0- 464002 44-467 45-4] 7328 0- 265796 32-697 22-00 4881] 0-214487 48-872 37-70 854 7310 0:473984 44-220 57-11 876 4861 0: 244082 17-506 56-91 7322 0- 231504 01-836 27-66 4875 0-481652 11-086 43-69 7330 0:294512 37-628 56-61 4884 0-274266 19-668 45-52 855 7268 0:292908 26-320 52-26 877 4822 0-291314 15-515 50-66 7269 0-373613 32-635 06-57 4839 0-310046 42-165 13-03 7292 0-333478 18-461 52°12 4847 0-398640 12-506 55-97 856 7256 0:381122 45-165 39-88 878 4820 0-292875 47-527 31-88 7277 0-308756 34-210 16-39 4846 0-372263 05-098 32-59 7303 0-310122 35-924 21-19 4849 0-334862 18-838 47-73 857 7696 0-379695 16-288 01-67 879 3617 0- 242315 47-941 46-90 7705 0-395216 41-953 03-40 4782 0- 284572 47-218 35-58 7709 0- 225089 14-429 38-10 4790 0-473113 54-161 44-64 858 7689 0-544647 29-369 18-67 880 4768 0-433148 33-491 45-73 7703 0-198112 29-478 22-94 4787 0-175497 31-232 36-03 7722 0-257241 54-223 14-34 3637 0-391355 22-041 13-70 859 7668 0- 284275 22-996 07-05 881 3607 0-326654 25°511 22°13 7696 0-481317 16-288 01-68 4769 0-285174 01-344 30-20 7708 0- 234408 14-424 46-64 4790 0-388172 54-161 44-64 860 7672 0-338857 15-469 51-80 882 3612 0-314368 56-554 57°35 7688 0-329132 26-238 24-48 4768 0-333407 33-491 45°73 7709 0-332012 14-429 38-10 4789 0-352225 33-922 51-45 861 7641 0-351958 16-780 19-09 883 3612 0-381416 56-554 57-35 7664 0-336796 43-239 54-72 3632 0- 256947 45-955 29-81 7692 0-311246 40-909 31-14 4768 0-361637 33-491 45-73 862 8716 0:343064 01-528 53-73 884 3618 0-434692 50-406 48-48 7660 0-393358 52-990 22-83 3634 0-186853 54-125 44-16 7700 0: 263578 35-012 59-31 4769 0-378455 01-343 30-20 863 8720 0-265192 13-266 36°21 885 3610 0-282714 09-629 22-05 8751 0: 273096 11-425 48-61 3624 0-336633 38-275 07-31 8762 0-461713 31-869 53-96 3627 0-380652 23-434 24-12 864 8723 0-277731 39-910 06-48 886 3614 0-380901 18-545 08-33 8750 0- 287292 07-534 37-99 3618 0- 249447 50-405 48-48 8761 0:434977 29-446 59-34 3628 0- 369652 25-672 19-26 865 8761 0:445130 29-447 59-34 887 3609 0-343210 59-668 42-59 8796 0-382459 54-740 02-78 3627 0-455987 23°434 24-12 8766 0:-172411 12-374 01-21 4927 0- 200803 35-146 53-40 866 8759 0-353126 02-768 04-79 888 3614 0-393083 18-545 08-33 8800 0:342912 28-247 05-56 3626 0- 349484 19-458 00-73 8770 0- 303962 21-908 49-88 3628 0- 257434 25-672 19-26 867 8761 0-316142 29-447 59-35 889 3624 0-356954 38-276 07-31 8799 0-418963 08-472 47-65 4919 0-395897 04-107 25°81 8776 0: 264895 27-195 41-00 4945 0-247148 03-728 30-59 868 8751 0: 251302 11-426 48-6] 890 4913 0-215240 07-537 36-44 8787 0:404961 51-639 31-38 4941 0- 201653 20-151 45-33 8794 0: 343737 39-394 19-72 3626 0-583106 19-458 00-73 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 Star 4925 4935 4946 4919 4943 4947 4948 4956 4973 4943 4969 4970 5211 5213 5230 5205 5218 5224 3758 3761 3767 3756 3757 3775 3734 3740 3756 3737 3744 3758 4857 4868 4883 4853 4876 4877 6405 6455 6472 6414 6449 6473 6463 6475 6516 6449 6493 6494 6475 6516 6425 6484 6518 6412 6375 6403 6493 6379 6429 6475 6366 6403 6493 6373 6375 6419 PRECISE OBSERVATIONS OF MINOR PLANETS Depend. - 266509 -288141 -445350 - 306863 -378822 -314315 - 279699 -398107 -322194 432322 285041 » 282637 - 300332 *324327 -37534] -221190 -419780 - 359030 - 273497 -513562 - 212941 - 266327 -432826 - 300847 -336538 - 246404 -417058 - 295508 - 540264 - 164228 -321392 -404718 - 273890 - 228687 -442408 - 328904 -326368 - 282994 -390638 - 281922 -498119 - 219959 - 297229 -414072 - 288699 - 236260 -317849 -445891 - 349096 -377050 - 273854 351540 399175 249286 - 267324 -373412 - 359263 -457412 - 264680 - 277909 -406682 - 340448 - 252870 - 271165 - 290456 -438379 TABLE II—continued Dec. °91 he -60 -81 ‘11 °31 -74 -74 -50 -13 -62 -38 -29 -73 -53 -43 -96 292 -26 -02 -55 -12 -09 -54 he) -75 “12 04 -40 -27 -74 -49 -84 -10 -6] -62 *85 -74 -01 a -78 *8] -42 “47 -29 eke) -66 -70 -47 -28 *45 *51 -46 -29 -4) -86 -66 *85 -74 -47 -13 -86 -66 -59 -4] -4] No. 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 Star 6333 6403 6453 6366 6370 6400 6261 6278 6320 6253 6299 6313 6217 6273 6264 6231 6236 6263 6186 6200 6209 6187 6206 6217 6126 6135 6155 6124 6148 6156 6088 6126 6208 6102 6108 6114 6088 6102 6172 6145 6181 6112 6118 6152 6167 6135 6147 6148 6125 6163 6477 6475 6513 6140 6490 6492 6532 6474 6512 6527 6550 6562 6597 6529 6588 6595 Depend. -363812 -353674 -282515 -585622 -251318 - 163060 -384989 -217461 -397550 -371178 -311820 -317002 - 384338 - 218476 -397186 230728 -473518 - 295754 - 273048 - 284996 -441956 - 384220 -393322 + 222458 - 279652 - 262563 -457785 -373234 - 303088 -323678 -473122 - 257674 - 269204 - 242710 - 260480 -496810 -176276 -422769 -400955 -352331 - 280126 -367543 -412670 - 218869 -368461 - 163875 - 226630 - 609495 - 304764 - 324036 -371200 - 362887 - 255351 -381762 -347451 238102 414448 300732 - 281830 -417438 213884 284246 -501870 - 226692 -411246 - 362062 R.A. -638 -303 - 660 “O91 -497 -984 -309 -185 -837 -053 277 -547 -516 “O72 -818 Eas) -373 -515 “1d -891 -748 -379 -605 -516 -419 -412 -137 -570 *212 -458 -021 -419 *355 -778 -790 02: -021 at -810 -436 -693 -347 52: -908 -446 -702 - 668 “T17 -596 -920 »054 -908 -795 -526 -080 »944 -460 -416 -116 -101 »244 -187 -600 -867 -512 -472 068 495 115 Dec. *25 -86 -86 -13 -17 -32 -2)1 -15 -52 ‘Il 64 -12 ak -64 -10 -39 -57 -16 -37 -87 -17 -68 84 ‘71 -61 -02 -98 -03 -20 -66 -50 -60 -60 “12 -42 -48 -50 -12 -85 -86 -40 -09 -49 *42 -90 “99 -87 “91 -53 -70 -16 -07 “21 -53 -54 -32 -61 -03 *92 *35 -12 -70 ‘01 -76 -20 -09 116 No. 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 Star 11451 11460 11490 11449 11469 11471 11415 11430 11433 11400 11437 11440 11237 11247 11272 11243 11246 11292 11149 11167 6538 11115 11194 6564 6495 6528 11115 6506 6526 11139 6398 6403 6432 6393 6451 6415 6386 6398 6415 6391 6422 6396 6340 6371 6381 6351 6360 6396 6351 6360 6389 6340 6371 6381 6363 6371 6389 6361 6380 9396 6370 6387 6410 6363 6395 6400 Depend. SSSSSSSSOSOSCSCSOSSOSOSO SOOO SOC OSC COO SOOO SOS SOS SOSOSOSOSOSOSOSSOSOSOSOSSSSSSSeSsSsSeSsssoesosososso -397613 - 380764 + 221623 - 244110 235264 520626 432909 224483 342608 321692 277014 401294 313002 -416973 - 270025 - 549268 -311978 - 138754 - 232179 - 384622 -383199 -445430 - 227503 - 327067 - 244812 -521091 - 234097 -512158 » 243542 - 244300 - 205401 -309974 -484625 -339866 - 278260 -381874 - 261658 -325960 -412382 - 323702 - 318282 -358016 - 182730 -397562 -419708 -305714 - 366555 -327731 - 274644 - 363085 - 362271 -171942 -489181 -338877 - 309362 - 369218 - 321420 -472806 - 281997 * 245197 -370790 - 269874 - 359337 * 259726 -323772 -416502 AS 18- 00: 57° 53° 56: 22: 30- 34: 03- 51- 10- 19- 37: 45- 35- 25> 39: 12: 04- 28- ll: 14- 16- 37: 14- 25: 14- 24- 59- -665 28: 28: 04- 32: 15: 32- 12- 28: 32: 24- 10- - 764 35- 48- 4]- 44- 08- Ol: 4]- 08 - 04- 35- 48- 4]- 49- 48- 04: 19- 15- -765 37: 01 01 Ol 4] 51 06- 789 255 438 934 553 819 453 071 706 608 307 594 228 307 396 700 348 679 573 121 991 296 637 035 677 844 296 629 691 585 115 702 403 417 558 804 586 557 909 848 145 236 822 144 871 765 144 871 589 145 236 822 164 236 589 284 784 507 -850 54: 49- -688 623 643 164 W. H. ROBERTSON TABLE II—continued Dec. No. 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 Star 6735 6783 6829 6769 6813 6760 6797 6848 6786 6760 6798 6839 6763 6784 6801 6760 6772 6808 6678 6693 6719 6667 6687 6722 6648 6657 6678 6647 6661 6688 6577 6600 6616 6563 6630 6650 6529 6544 6510 6525 6585 6492 6458 6505 6512 6477 6478 6509 6414 6445 6447 6419 6434 6477 6370 6424 6872 6828 6915 6400 6851 6900 6402 6861 6862 6897 Depend. *324965 - 340877 -334158 - 296208 -317583 386209 247491 317173 -435336 314000 -399181 - 286820 - 227899 -314836 -457265 - 257816 - 325087 -417096 -373236 - 324260 -302504 - 243414 - 388576 - 368010 260750 365332 373918 424937 303704 - 271360 -468976 - 227732 - 303292 -372683 - 220408 -406909 -218512 -335624 -445863 - 230792 - 202910 - 566297 - 386291 - 209090 -404619 - 215078 -343428 -441494 - 240288 -328216 -431496 -370083 -346008 - 283909 376868 254714 368418 263428 -218818 -517753 - 342576 - 299008 358417 439100 207960 - 352940 PRECISE OBSERVATIONS OF MINOR PLANETS 117 TABLE II—continued No. Star Depend. R.A Dec No Star Depend. R.A Dec 979 6878 0-419632 38-779 03-89 987 5486 0-501998 57-08 15-9 6900 0-319516 30-348 53-66 5506 0: 166920 32-43 48-3 6936 0: 260852 55-802 02-59 5530 0-331082 03-81 08-8 980 6865 0:427652 50-016 10-05 988 5465 0: 224590 03-55 16:8 6923 0: 287646 58-717 14-61 5516 0:475334 29-10 03-8 6926 0: 284702 45-677 24-11 5518 0: 300075 46°51 13-5 981 6901 0°372775 31-795 45-72 989 5486 0:346580 57-08 15-9 6932 0-301345 14-628 32-71 5518 0-300992 46°51 13-5 6936 0-325880 55-802 02-59 5530 0:352428 03-81 08-8 982 6878 0-353606 38-780 03-89 990 5494 0: 389483 38-96 12-0 6923 0: 279205 58-717 14°61 5496 0: 263760 46-75 30-5 6957 0-367189 23-103 16-03 5537 0-346757 09-59 26°7 983 5192 0: 246012 20-04 10-8 991 5563 0: 294274 42-564 15:78 5236 0: 420334 20-19 43-2 5622 0: 408712 11-397 56-37 5241 0-333654 04-14 10-9 5624 0:297014 24-386 23-61 984 5209 0-358582 31-11 20-2 992 5566 0:340738 51-203 36-99 5229 0-310074 26-75 52-9 5598 0: 304058 23-574 28-25 5242 0-331344 13-11 20-5 5641 0° 355204 30-850 04-44 985 5177 0: 422606 30-63 32-0 993 5615 0-310369 32-697 11-42 5210 0: 261198 42-55 59-1 5680 0:337116 03-234 13:28 5220 0-316196 30-13 07-0 7517 0:352515 02-620 03-51 986 5182 0-321712 56-67 40:4 994 5622 0: 306539 11-397 56:37 5195 0:329581 30-19 11-0 5641 0: 243516 30-850 04:44 5225 0-348706 55°44 28-4 7534 0-449945 32-455 33-97 (Received 23 September 1969) Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 119-121. 1969 Occultations Observed at Sydney Observatory during 1967-68 kK. P. Sims The following observations of occultations were made at Sydney Observatory with the 114-inch telescope. A tapping key was used to record the times on a chronograph. The reduction elements were computed by the method given in the occultation Supplement to the Nautical Almanac for 1938 and the reduction completed by the method given there. Since the observed times were in terms of coordinated time (UTC), a correction which was derived from Mount Stromlo Observatory Bulletins A was applied to the 1967 observations to convert them to universal time (UT2). For 1968 the corrections to the observed times in UTC were derived from Bureau International De L’Heure Circulaive D. In 1967 a correction of +0-01028h (=37 seconds) was applied to the time in UT2 to convert it to ephemeris time with which The Astronomical Ephemeris for 1967 was entered to obtain the position and parallax of the Moon. In 1968 this correction places of the stars of the 1967-68 occultations were provided by H.M. Nautical Almanac Office. Table I gives the observational material. The serial numbers follow on from those of the previous report (Sims, 1967). The observers were W. H. Robertson (R), K. P. Sims (S) and H. W. Wood (W). Except for occultations 497, 498 and 525 which were reappearances at the dark and bright limbs, the phase observed was disappearance at the dark limb. Table II gives the results of the reductions which were carried out in duplicate. The Z.C. numbers given are those of the Catalog of 3539 Zodzacal Stars for Equinox 1950-0 (Robertson, 1940). References RoBErtTson, A. J., 1940. Astronomical Papers of the American Ephemeris, Vol. X, Part IT. Sims, K. P., 1967. J. Proc. Roy. Soc. N.S.W., 100, was +0-01056h (=388 seconds). The apparent 189. Sydney Observatory Papers No. 56. TABLE I Serial Z.C. No. No. Mag Date UlT.2 UT2-UTC Observer 493 0598 5°7 1967 Mar. 17 9 20 49-34 +0-03 R 494 1416 7-2 1967 Apr. 19 12 39 53-06 +0-03 R 495 1647 6-7 1967 Apr. 21 9 31 41-55 +0-03 S 496 2025 6-8 1967 Apr. 24 10 50 07-86 +0:03 R 497 2480 5+3 1967 Apr. 27 14 34 37-23 +0-03 S 498 2479 5:3 1967 Apr. 27 14 34 42-03 +0-03 S 499 1733 5:°2 1967 May 19 13 21 10-43 +0:04 W 500 1544 5:7 1967 July Ill 7 55 53°83 +0-04 WwW 501 2424 6-9 1967 July 18 8 37 50-63 +0-04 R 502 2427 7-1 1967 July 18 9 53 03-67 +0-04 R 503 1134 5-0 1968 Apr. 6 9 O01 56-53 +0:02 WwW 504 1137 5-1 1968 Apr. 6 9 22 04-62 +0-02 W 505 1139 8-0 1968 Apr. 6 9 54 33-69 +0-02 W 506 1740 7-6 1968 June 5 10 04 42-58 +0-02 R 507 1746 a | 1968 June 5 12 59 27-27 +0:02 5 508 1865 7:2 1968 June 6 13 16 16-57 +0-02 S) 120 K. P. SIMS TABLE I—Continued Serial ZG. No. No. Mag Date Wete2 UT2-UTC Observer 509 1966 8-1 1968 June 7 8 15 31-83 +0-02 R 510 1596 7-0 1968 July 1 7 46 58-92 +0-03 R 511 1603 7-1 1968 July 1 10 09 26-62 +0-03 R 512 1824 7°8 1968 July 3 12 51 13-28 +0-03 S 513 1911 7-1 1968 July 31 11 32 36-37 +0-03 R 514 2031 8°7 1968 Aug. 1 12 26 18-67 +0-03 S 515 2153 8°4 1968 Aug. 2 12 02 32-34 +0-03 R 516 2289 8-1 1968 Aug. 3 8 26 52-74 +0-03 WwW 517 2299 6-4 1968 Aug. 3 11 02 19-10 +0-03 WwW 518 2449 7:5 1968 Aug. 4 8 18 19-20 +0-03 WwW 519 2470 6-1 1968 Aug. 4 13 43 09-24 +0-03 WwW 520 2617 4:7 1968 Aug. 5 7 58 55-13 +0-03 WwW 521 2644 6-3 1968 Aug. 5 12 35 48-96 +0-03 WwW 522 2257 6-7 1968 Aug. 30 11 02 43-83 +0-02 Ss 523 2366 1-2 1968 Sept. 27 8 30 48-73 +0-01 S 524 2373 6-2 1968 Sept. 27 9 36 23-26 +0-01 S 525 2366 1-2 1968 Sept. 27 9 36 51-19 +0-01 S 526 2536 7-4 1968 Sept. 28 11 05 20-10 +0-01 WwW 527 3180 8-2 1968 Oct. 2 12 48 38-33 +0-01 R 528 2489 8°5 1968 Oct. 25 10 10 37-83 +0-02 S 529 3391 6-8 1968 Oct. 31 9 48 09-79 +0-02 WwW 530 3389 7°6 1968 Oct. 31 9 52 36-95 +0-02 W 531 3388 5-6 1968 Oct. 31 10 03 41-93 +0-02 WwW 532 3394 7°4 1968 Oct. 31 10 56 44-22 +0-02 W 533 2583 5-8 1968 Nov. 22 9 22 26-76 +0-02 S 534 3240 6:6 1968 Nov. 26 12 40 07-23 +0-02 R TABLE II : Luna- Coefficient of Serial 5 tion Pp p? pq q? Ao pAs qAcs Noe = Ne : Aw AS 493 547 +64 +77 41 +49 59 —0°-5 —0-3 —0-4 +5-6 +0-91 494 548 +67 —74 45 —50 55 0-0 0-0 0:0 +5-°3 —0-93 495 548 +80 —60 64 —48 36 +0-6 +0-5 —0-4 +6-7 —0-89 496 548 +90 +43 81 +39 19 —1-1] —1-0 —0-°-5 +14-7 0-00 497 548 —70 —71 49 +50 51 +0-8 —0°-6 —0-6 —10-7 —0-60 498 548 —71 —7] 50 +50 50 —0:2 +0:1 +0-1 —10-8 —0-59 499 549 +74 —67 55 — 50 45 —0°3 —Q-2 +0-2 +5-] —0-94 500 551 +77 —63 60 —49 40 +0°5 +0-4 —0°-3 +6-4 —0-90 501 551 +98 —18 97 —18 3 +0-1 +0:1 0-0 +12-6 —0:36 502 551 +94 —34 88 — 32 LZ —0°-3 —0°-3 +0-1 +11-6 —0-51 503 560 +89 +46 79 +4] 21 —1-4 —1-2 —0-6 +12-5 +0-33 504 560 +98 —20 96 —20 4 —0-5 —0°-5 +0-1 +12°-4 —0-34 505 560 +100 + 2 100 +2 0 +1-4 +1-4 0:0 +13-1 —0-14 506 562 +87 —49 76 =43 24 +0-5 +0-4 —0-2 +8-1 —Q-84 507 562 +74 —68 54 —50 46 +1-5 +1-] —1-0 +4-9 —0-95 508 562 +96 —28 92 —27 8 —2:0 —1-9 +0-6 +10-7 —0-70 509 562 +59 —8l 35 —48 65 +0°8 +0:°5 —0°6 12-7 —0-98 510 563 +97 +25 94 +24 6 —0:-7 —0°7 —0-2 +14-4 —0-22 511 563 +97 —23 95 —22, 5 —1-5 —1-5 +0°3 +11-2 —0-65 512 563 +84 +54 71 +45 29 +0:6 +0°:5 +0:3 +15:0 +0-08 513 564 +47 +88 22 +41 78 —0-1 0:0 —0-1 +12:-1 +0°58 514 564 +97 OAs 94 +24 6 +0-9 +0°9 +0-2 +14-3 —0-17 515 564 +81 +59 65 +48 35 —0-9 —0°7 —0°5 +13-5 +0-28 516 564 +76 +65 58 +49 42 —0-8 —0°6 —0-°-5 +12-3 +0-43 517 564 +100 +6 100 +6 0 +0-1 +0-1 0:0 +13-4 —0-19 518 564 +86 +51 74 +44 26 —0:3 —0°3 —0Q-2 +12°4 +0-38 519 564 +52 —85 27 —44 13 +1-0 +0-5 —0°8 +5°5 —0-91 OCCULTATIONS OBSERVED AT SYDNEY OBSERVATORY DURING 1967-68 121 TABLE II—continued Serial Luna- Coefficient of No tion p q q? pq q? Ac pAc qAc ; No. Ac Ad 520 564 +45 —89 20 — 40 80 +0:7 +0°3 —0°6 +5:°8 —0-90 521 564 +97 +26 93 +25 7 —0:°4 —0-4 —0-l +13-2 +0:03 522 565 +90 +43 81 +39 19 —0-6 —0:°5 —0:3 +13:°5 +0-16 523 566 +93 —37 86 —34 14 —0°3 —0°3 +0°-1 +11-2 —0°55 524 566 +81 —58 66 —47 34 +2:°0 +1:°6 —1-2 +9-2 —0-73 525 566 — 86 — 52 73 +44 27 —0-l +0:-1 +0-] —12°6 —0-34 526 566 +72 —70 51 — 50 49 +0°-6 +0:4 —0°4 +8-:9 —0:74 527 566 +100 —8 99 —8 1 0:0 0-0 0:0 +13-6 +0-31 528 567 +98 —19 96 —19 4 +0-1 +0°-1 0:0 +12:8 —0-28 529 567 +99 —16 97 —16 3 —0-2 —0-2 0:0 +14-] +0°32 530 567 +73 +68 53 +50 47 —0:-2 —0Q:1 —0-l +4:°9 +0°94 531 567 +45 +89 20 +40 80 —0-°2 —0-l —0-2 —0-1l +1-00 532 567 +94 —33 89 —3l1 11 —0:7 —0°7 +0°2 +14:-7 +0-14 533 568 +99 —12 99 —12 1 +0°-1 +0:1 0:0 +13:1 —0-14 534 568 +40 —92 16 —37 84 +2°-4 +1-0 —2-2 +10°9 —0-66 (Received 4 September 1969) Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 123-124, 1969 A Note on a Kinematical Derivation of Lorentz Transformations A. H. Kotz Depariment of Applied Mathematics, The University of Sydney 1. There is a close analogy between the assumptions of Milne’s Kinematical Relativity (Milne, 1948) and the &-calculus with the help of which Bondi (1964) derives Lorentz trans- formations. In both accounts a rigid measuring rod is replaced by measurements of distance carried out by means of light signals. This is particularly appropriate when “ distant ’’ events are being observed since a ‘‘ measuring rod ”’ can, at best, be transported only to the nearest celestial bodies. Kinematics based on signalling techniques will be called “‘ Radar Physics’’. The purpose of this note is to analyse the axioms needed to derive the velocity formula of Special Relativity from which the Lorentz transformations can be easily obtained. All observers (and all observable events) of Radar Physics are assumed to be equipped with a signal-sending device, a mirror capable of reflecting signals instan- taneously, and with aclock. It is also necessary to assume that an observer can measure local velocities; that is, that he can determine relative to himself, the speed of any signal he may send or receive. Likewise, he must be able to measure (again relative to himself) the speed of any observer who passes close to himself (coincides instantaneously at a given point in space). Two observers, O and O’, situated at different points in space, can easily determine whether they are at rest relative to each other, or not. In fact, let 4, and ¢, be the times of emission of consecutive signals as recorded by O, and let t, and #, respectively be the times when he _ Teceives these signals back, after their reflection py O’. If (1) O’ is said to be at rest relative to O, even if the velocity (according to O) of the reflected signal Should differ from that of the emitted one. ty —ty=l,—t,, e ‘0 6, @' .6 ‘e is” We must assume, however, that there is no fluctuation in the direction of their relative motion, if any. By repeating the above experiment several times in succession, O can also discover whether O’ is in a state of uniform motion relative to himself. To simplify the analysis, let us assume that an observer always sends and receives signals with the same speed c. He cannot have any knowledge of what happens to the signal in transit. Hence he is constrained to define distances as if the transit speed of his signals were the same as measured locally. The relativistic principle of constancy of the velocity of light becomes then a purely local concept. 2. Let O and O’ coincide initially in space. At that instant they can synchronize their clocks to read t=t',=0. Let us suppose also that O finds O’ moving with a speed U— Casas so that V is. dimensionless. Furthermore, let O and O’ observe a distant event E which remains, for the sake of simplicity, in their mutual line of sight (so that O, O’ and E are collinear in a flat space-time). If a signal sent by O at ¢,=0 is reflected by E att, (on E’s clock ; ¢, is not O-observable), and received by O again at ¢,, the distance %, of E as calculated by O, is oe e ee @ 8 Hence c ty= ht, a= oh O then repeats the experiment with initial and final time readings ¢, and ¢, respectively, to get, say c X= 5 (t2—t3), tp=3(tg+t). .. .. (3) 124 In this case, O would conclude that in the course of the observations E moved from A to B with an average speed %p—%*4 ty u= ars =e(1 2 ). In a similar way O’ obtains for the “ speed’ of E relative to himself uniform coee eee ee Let A transformation law between w’ and wu (that is, the addition formula for velocities) corres- ponds, therefore, to a relation between k and k’. 3. Let us suppose that this transformation is of the form R’=f£(V)k+e(V), ........ (7) where f and g are at most bilinear functions of V, for all conceivable cases of uniform relative motion of O, O’ and E. When O and O’ read, on their respective clocks, ty=ly, th=to, the event FE coincides with them initially. Hence f(V)+g(V)=1, for all V. . (8) If O and O’ travel together so that their clock readings remain the same, we have 7 (0) =) (chat is,72(0)—0) seo) Next, suppose that O’ travels with the signal so that he is unable to communicate with O except by reversing his velocity with the consequences familiar from the discussion of the “clock paradox” of Special Relativity. In other words, we have k’=1 when V=1, or J(ij=—0 (or 24) — 1), . (10) Finally, let O’ regard himself at rest, so that the relative velocity of O and O’ is reversed (hitherto we have been viewing the situation as it appears to O). We obtain afl ol aS a) By comparison with (7), we have yy ae eee (U Ke Oi ee (11) The conditions (8)—-(11) are sufficient to determine f and g uniquely. Indeed A. H. KLOTZ 1—V 2V iW) = my and g(V) iv (12) or , as =) 1 = 2) 4. By equations (4), (5) and (6), (13) becomes Ejinstein’s formula for the addition of velocities : Fi et, Special Lorentz transformations follow in the usual way providing we assume equivalence of the observers O and O’. For example, it is sufficient to require that O’s clock should go faster than that of O’ if the former regards himself as being at rest and conversely. It is clear that the clocks of O and of O’ must register differently in any case. It is harder to interpret the assumption involved in writing down (7). There seems to be no a priori reason for not having ay) ae iy £ (V), Sivonen teh oie (15) instead. Of course, if the transformation between k and hk’ is linear, that between t k amis — is bilinear and conversely. In the latter yond case, an additional condition (for example, that k=0, implies k’=0)is necessary if (14) is to result. It follows that the choice made here (equation (7)) is to be preferred on the grounds of simplicity. SUMMARY A set of axioms is proposed for the derivation of Lorentz transformations in Bondi’s “‘ Radar Physics ”’. Acknowledgement I wish to express my gratitude to the Referee | for helpful comments. References Kinematical Relativity. Oxford. Lisbon. MILNE, E. A., 1948. Bonpt, H., 1964. In Cosmological Models. (Received 4 June 1969) | Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 125, 1969 Lorentz Transformations and Invariance of Maxwell’s Equations A. Hie KEOTZ Department of Applied Mathematics, The University of Sydney It is well known that one of the fundamental assertions of the Theory of Special Relativity is the invariance of Maxwell’s equations under Lorentz transformations in a flat space time continuum. The converse of this result is that if Maxwell’s equations are invariant under a certain general class of linear transformation then the latter belong necessarily to the repre- sentations of the Lorentz group. Validity of the converse is less frequently realized. We shall prove it in this note. Let us write Maxwell’s equations in the standard, four-dimensional notation : fuvy=Su, uv —Pvu—Puv, where Greek indices go from 1 to 4, comma denotes partial differentiation with respect to the coordinates x,, and the summation con- vention over repeated indices is used. , is the four-vector potential and S,, the four-current density vector, and we restrict ourselves to a flat, pseudoeuclidean space time so that no distinction between covariant and _ contra- variant vectors needs to be considered a prior. Indeed it is convenient to work in a linear vector space & to which %,, Sy, etc., belong and in which the field tensor fy, represents an ordinary bilinear mapping. The equations (1) and (2) are assumed to be invariant under a group of linear endomorphisms Bi >: RANK Bis sk doe Dad tS (3) which induce on any vector veX an identical transformation UENO “sheaths sa Beene (4) We shall say that the endomorphisms A form the Lorentz group if AA ATAqy, the identity transformation, and A? is the adjoint (or transpose) of A. We assume that & admits an inner product, so that, for any ved, also f-veX. The require- ment of invariance implies that Gi i en Te eee (6) (6) 1s an additional assumption in the proof. However, it says little more than that f is a tensor field. It is sufficient to consider only the first set of Maxwell’s equations (eq. (1)). The second set (eq. (2)) then serves to define the structure of the electromagnetic field. From equations (4) and (6), we have f'-v'=f’-Av=(f'A)-v=Af 9, oe We can write equation (1) in the form TE=S oe ee Oe ee (8) where x is the differential divergence operator. Then yx belongs to the dual space of & (e.g., so that Raikov, 1965) and_ therefore transforms according to the law 1 ay ee ee (9) Since we have similarly to (6) EC) aye arte eens (10) the last two equations give Px =4fx —AfA*,, or | es P- rea eee (11) But the transformation (3) of the coordinates induces a unique transformation law of the field tensor. Hence, comparing (7) and (11), we have AAS which is equivalent to the Lorentz transformation. > 2 2 © © > ww es © definition (5) of a Acknowledgements The author wishes to acknowledge with gratitude a helpful conversation with Professor J. P. O. Silberstein of the University of Western Australia and equally helpful comments by the Ineietee: Reference Ratikov, D. A., 1965. Vector Spaces. Groningen, (Received 4 June 1969) Census and Statistics. through later citations. Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 127-135 1969 The First Commonwealth Statistician: Sir George Knibbs* SUSAN BAMBRICK Australian National University The Constitution of the Commonwealth of Australia empowered the national government to engage in census-taking and_ statistical compilation and publication, and a Census and Statistics Act was passed in 1905, authorizing the creation of the Commonwealth Bureau of Census and Statistics. In the following year its work began under the direction of George Handley Knibbs. (1) BIoGRAPHICAL NOTES Knibbs was born in Sydney on 13th June, 1858, the son of John Handley Knibbs. He was educated as a surveyor and joined the General Survey Department of New South Wales in 1877, resigning in 1879 to take up private practice; in 1889-90 he joined the teaching staff of the University of Sydney’s Engineering School as an independent lecturer in geodesy, astronomy and hydraulics, an appointment nominally held till 1905, when he was appointed Director-General of Technical Education for New South Wales and also Acting Professor of Physics at Sydney University. He joined the Royal Society of New South Wales in 1881 and was Honorary Secretary and Editor of its Journal and Proceedings for a total of nine years, and President in 1898-99. To 1906 he made 14 contributions to the Journal, mostly of a technical nature and arising from his work. He was also variously President of the Institution of Surveyors,? Sydney, of the New South Wales Branch of the British Astronomical Society,? and of the Society for Child Study. In 1902 he represented the University of Sydney on the board composing regulations for adminis- tering Cecil Rhodes’ bequest providing scholar- ships to Oxford, and in 1902-03 travelled through Europe as a member of a commission on education.4 He visited Europe from April * The bibliographical details for this note were drawn from the catalogue of the National Library of Australia and from the catalogue (incomplete) and shelves of the Library of the Commonwealth Bureau of Many references were traced to December, 1909, representing Australia at the International Congress on Life Insurance (Vienna), on the special committee revising the nomenclature of diseases (Paris), at an Inter- national Congress on the Scientific Testing of Materials (Copenhagen), at the International Institute of Statistics (Paris), and at the Geodetical Congress in London. While Commonwealth Statistician, Knibbs sat on the board reporting on possibilities of the Canberra site and on the Royal Commission investigating the problems of trade and industry in war ; he was a consulting member of the 1915 Committee on Munitions in War and sat on other wartime committees, and was chairman of the Royal Commission which in 1918-19 considered the taxation of Crown leaseholds. In 1919 he represented Australia at the London conference on double income tax and war profits, in 1920 attended the British Empire Statistician’s Conference in London (chairing the Census Committee), and in 1921 was elected vice-president of the International Eugenics Congress, New York. During his lifetime he received various honours, of which he was perhaps inordinately proud. He was created C.M.G. in 1911 and Knight Bachelor in 1923, was variously an Honorary Fellow of the Royal Statistical Society, a Fellow of the Royal Astronomical Society, an Honorary Member of the American Statistical Association and of the Statistical Societies of Paris and of Hungary, and a member of the International Institute of Statistics, the British Science Guild and the International Association for Testing Materials. In 1921 he presided over the Social and Statistical Section of the Conference of the Australasian Association for the Advancement of Science, and in 1923 was its General President. In 1921 Knibbs had left the Bureau to become Director of the newly constituted Common- wealth Institute of Science and Industry, resigning in 1926 and living in retirement till his death on 30th March, 1929. 128 (2) KNIBBS AS STATISTICIAN Knibbs considered his duties to extend far beyond the boundaries of statistical collection and processing in fields dictated by others. He saw himself as “ assisting the administrative statesman with his counsel and advice ’’,® and it was to this end that he published such works as his report on social insurance, where he elaborated an organic theory of the state and justified public health measures on the grounds of national development’ rather than humanitarianism.?’ His major interest was in vital statistics, and it was here that he won his international reputation. Here too he became involved in theory, embracing at least in the later part of his. life a doctrine he labelled ~ The New Malthusianism ’’. He considered that at current growth rates the world would reach human capacity in two and a half centuries. Although he advocated increased population for Australia as necessary for self-preservation, he warned against indiscriminate immigration, thus reflect- ing contemporary government policy as well as social thinking.® Knibbs was a mathematician and statistician rather than an economist,’ although he was concerned with studying such phenomena as unemployment and fluctuations in the purchas- ing power of money. His emphasis within statistics was on social problems and improve- ment of the human condition. In his data collection he was always hampered by lack of co-operation from his hoped-for respondents, for his expectations of others were high. His suggestions for a detailed nosological classi- fication! would have placed considerable strain on the medical profession, despite its undoubted worth, and his cost of living enquiries" were too onerous for most housewives to respond. Knibbs was a keen advocate of international statistical co-operation, and in particular of an international statistical institute as an offshoot of the League of Nations, but he had to be satisfied with a less grandiose Imperial statistical bureau.” (3) KNIBBS AND THE EARLY WORK OF THE COMMONWEALTH BUREAU OF CENSUS AND STATISTICS (i) Unification of Statistical Collection ‘Uniform statistical requirements for the Australian colonies were originally set by the British Government, but after the granting of responsible government divergences arose. In most States individual departments prepared SUSAN BAMBRICK their own statistics for a central collating department, and six pre-Federation conferences of State Statisticians failed to achieve uniformity in the methods, subjects and timing of statistical enquiries. Even in census-taking uniformity had proved impossibie, although as the methods of individual colonies were based on United Kingdom practices they were similar. a \ 40 a SF es ae pF NLL LG ms A AUVONNOR NaaisaMm — i] NY < tr = / »? .. ~ A OLA k =z : ») @) \ N oNWi3a 1ev1 b \ x vo @ \ Zax 9 SONIX ais) Yeas5 ey \ a sx ME Wud TVNOILVN RAaTIVA Ay aa | a SNIVLNQNOW anna (x) } x NoS3IWve faa) -s~ 7 _ © em froouenais NN \ me 4 | \ : | / x ane } vaunaviins, — | / | \ 040 4000Mg— — — A ff owe iN s1iv4 eno al me | / _ € x ['o esa’ irs Mecouaes Nou ae vunare’ \ We ] a ~ oe Jo 4004013 2m Al nd Ye, oa rs Rew ii rs \ eee wee aD pes ~ aa (a yoo" per = TAS NaOH! ya eee tom oe - by x = vaN /«” - ~ 1» aa oo eee iene eee er oo Sx ~ GOOMONI HGS Oo = =——=6¢ yom / : on J eu a ul { j ret / ol jee? -_ 138 139 TRIASSIC STRATIGRAPHY—BLUE MOUNTAINS, NEW SOUTH WALES MIIVI ) 80 yw ae ‘uorjeus0, Aepeg oy} jo deur yoedosy—'z “OL 6 rhe 7 / v ! S3TIW NI / / = : : \ $2 ™ \ ay \ ol vaG = . \/ VWAUNBLINI YNOLNOD 93/ IF S zt \ \ iN a \ \ A ~ \\ : 9 3 =~ e © us = = i VIFHD \ \ "So \ of! 75s ans GYu043000M pee | VENQOLY Ye =e _-— ee —_—— a \ -—" 038? a \ Rest NO <. \ oo, Cee ‘ KG 5 Ss SS HLV3HNOV 19 4 \ “AS “ 140 ROBERT H. GOODWIN TABLE 1 Stratigraphy of the Blue Mountains System Group | Formation Member Wianamatta | Ashfield Shale Group | Mittagong Formation Hawkesbury Sandstone Burralow Formation O | Banks Wall Sandstone = Grose 29) | Mount York Claystone n Sandstone ——— < Narrabeen Burra-Moko Head Sandstone i—l = m Group Hartley Vale Claystone ES Govett’s Leap Sandstone Caley Victoria Pass Claystone Formation Clwydd Sandstone Beauchamp Falls Shale Illawarra | PERMIAN Coal Measures The Caley Formation crops out at the base of the cliffs from Narrow Neck Peninsula to McMahon’s Point, and in parts of Erskine Creek. The formation thickens to the east and south (Figure 2). At Katoomba it is 120 feet thick, whereas in the Bedford Creek Bore (Figure 1) it measures 162 feet. In the Kurrajong Heights No. 1 Bore located to the north and east of the study area the unit has a thickness of 250 feet. In the Blue Mountains the Caley Formation has been subdivided into the five members of Goldbery (1966). However, in the Erskine Creek area, the middle member, the Victoria Pass Claystone is absent. The Caley Formation is distinguished from the Grose Sandstone by the presence of greater quantities of shale and claystone and by a slightly higher lithic content of the sandstones. Within the Caley Formation the thickness of individual members is quite variable, however the overall thickness of the formation changes only gradually. The lithology of the Caley Formation is discussed with reference to the individual members. BEAUCHAMP FALLS SHALE MEMBER In all sections examined the Beauchamp Falls Shale forms the basal member of the Caley Formation. It is overlain by the Clwydd Sandstone and underlain by the Katoomba Seam, the uppermost unit of the Illawarra Coal Measures. It consists of interbedded carbon- aceous shales, siltstones, claystones and fine-grained sandstones, a lithology which is distinctive in outcrop and easily identifiable even where the Katoomba Seam is absent. A fluctuating depositional environment has produced marked variations in the thickness of this unit. Inthe Bedford Creek Bore it measures 31 feet 4 inches, at Wentworth Falls 17 feet, at the Valley of the Waters 28 feet, at Leura Falls 5 feet 8 inches, and at the Giant Stairway, Katoomba, 12 feet 9 inches. CLWYDD SANDSTONE MEMBER The predominant lithology of the Clwydd Sandstone is a coarse-grained quartz lithic sandstone. Occasionally this member contains fine-grained sandstones and lenticular clay- stones. Red and green subangular jasper pebbles up to } inch in diameter are not uncommon in the coarse fraction. The thickness of the member is variable. At Golden Stairway on Narrow Neck Peninsula, it is 17 feet, in the Bedford Creek Bore 26 feet 4 inches, while in Erskine Creek, where the TRIASSIC STRATIGRAPHY—BLUE MOUNTAINS, NEW SOUTH WALES Victoria Pass Claystone is absent, it attains a maximum thickness of 130 feet. VICTORIA PASS CLAYSTONE MEMBER The Victoria Pass Claystone is the middle unit of the Caley Formation. It is recognizable by the hard dense grey claystone of which it is made up and the tendency of the unit to be eroded, forming a notch in the cliff face. The absence of the Victoria Pass Claystone in Erskine Creek makes the distinction between the Clwydd Sandstone and the Govett’s Leap Sandstone tenuous. The thickness of the Victoria Pass Claystone is variable. In the Bedford Creek Bore it is 17 feet 1 inch thick and is comprised of fine grey shale with some silty bands. Along the cliffs from Wentworth Falls to Katoomba, a distance of four miles, variations in thickness are quite apparent. At Wentworth Falls the thickness is 7 feet 1 inch, at Valley of the Waters 24 feet, at Leura Falls 9 feet, and at the Giant Stairway, Katoomba, 4 feet 6 inches. With the exception of the Bedford Creek Bore, there is little variation in lithology throughout the study area. It is composed of a medium to dark grey, hard, dense claystone. GOVETT’S LEAP SANDSTONE MEMBER The Govett’s Leap Sandstone is a fine- to coarse-grained quartz lithic sandstone. It contains a clay-rich matrix that tends to render the rock quite friable. In the Bedford Creek Bore the basal 4 feet 7 inches of the Govett’s Leap Sandstone is a fine, light greenish grey conglomerate. This is the only occurrence of conglomerate in the Caley Formation within the study area. The thickness of the Govett’s Leap Sandstone is variable. In the Bedford Creek Bore it is 57 feet 8$ inches, while at Leura Falls it is 83 feet, and at the Golden Stairs on Narrow Neck Peninsula only 33 feet 6 inches. HARTLEY VALE CLAYSTONE MEMBER The Hartley Vale Claystone is the uppermost unit of the Caley Formation. It is distinctive as a fine-grained unit that usually forms a notch on the cliff face due to erosion and marks the base of the cliff, forming Grose Sandstone. The less resistant nature of this unit and the tendency of the overlying Grose Sandstone to fracture along vertical joint planes is presumably the reason for the formation of the great precipices for which the Blue Mountains are famous. If the Hartley Vale Claystone were more resistant C 141 to erosion than the Grose Sandstone, the develop- ment of talus slopes, similar to those associated with the Burralow Formation, would be expected. The lithology of the Hartley Vale Claystone ranges from fine-grained sandstone to claystone and shale. The average thickness of the unit is 8 feet and variations are relatively small. With the exception of the Valley of the Waters, the unit is easily recognizable throughout the area studied. At the Valley of the Waters the lower portion of the Grose Sandstone contains numerous claystone bands and the _ precise position of the boundary between this unit and the underlying Caley Formation is uncertain. Grose Sandstone The Grose Sandstone, the middle formation of the Narrabeen Group, was named by Crook (1956) after the outcrops in the Grose River Valley. Here the massive sandstone attains thicknesses of 700 feet and forms majestic cliffs. The Grose Sandstone also forms the cliffs of the Jamieson and Megalong Valleys. The Grose Sandstone crops out on the surface of the Blue Mountains Plateau from Lawson to Katoomba and in many of the river valleys in the study area. It has been subdivided into three members by Goldbery (1966). Grose Sandstone : Banks Wall Sandstone Member. Mount York Claystone Member. Burra-Moko Head Sandstone Member. The presence of the Mount York Claystone Member was confirmed by the author, who also found another continuous claystone horizon, usually distinctive by its reddish brown colora- tion, below the Mount York Claystone. This lower claystone is very useful as a marker horizon and can be used for mapping purposes. In order to prevent the nomenclature from becoming chaotic, this lower red brown claystone has not been given member status but herein is referred to as the ““ Unnamed Claystone Marker Bed ”’. UNNAMED CLAYSTONE MARKER BED* The “ Unnamed Claystone Marker Bed ”’ is a lower reddish brown claystone which crops out an average of 150 feet above the base of the Grose Sandstone. Generally it occurs between 130 and 170 feet above the base of the Grose * At the time of writing the nomenclature of the Blue Mountains is in a state of revision (see ‘‘ Geology of the Western Blue Mountains’’, N.S.W. Geol. Survey Bull. 20). Until finalized, the informal name of Katoomba Claystone is proposed for this unit. 142 Sandstone, whereas the Mount York Claystone is located 340-400 feet above that level. Along the cliff faces these two horizons are easily recognized by (1) their red coloration, (2) their weathering to form an erosional notch, and (3) by a line of trees commonly growing upon them. The reddish brown coloration is in places intermittent, although persistent, and represents the only reddish-brown claystones in the Narrabeen Group of the study area. The “Unnamed Claystone Marker Bed”’ is continuous and may be traced along the cliffs from Narrow Neck Peninsula (Plate I) to McMahon’s Point, a distance of almost 20 miles. It is evident in the Bedford Creek Bore, where the base is 127 feet above that of the Grose Sandstone and the thickness is 8 feet 6 inches. The contacts with the sandstones above and below are sharp and straight, virtually no brecciation or gradation being observed. In some stratigraphic sections, such as at the Giant Stairway, Katoomba, the claystone is split into several bands. The claystone bed normally forms an erosional notch on the cliff face (Plate II), while the colour varies from reddish brown to mottled, white and light grey. The existence of this horizon was not noted by Goldbery (1966) in the Grose Valley. He does refer to a reddish-brown claystone, 5 feet 6 inches thick, in his Govett’s Leap Stratigraphic Section, but states that it is lenticular ‘“‘ when observed on the nearby cliff face ”’ The continuity and relatively constant thickness make the ‘“ Unnamed Claystone Marker Bed ”’ useful for correlation and mapping. It is felt that re-examination of adjacent areas such as the Grose Valley and Burragorang Valley will show the presence of this horizon. BuRRA—MoKo HEAD SANDSTONE MEMBER The lower member of the Grose Sandstone, the Burra-Moko Head Sandstone, has a maximum thickness in the study area of 670 feet at the Bedford Creek Bore. The unit thickens in a north-easterly direction (Figure 3) across the mapped area. The anomalous thick- ness centred on the Bedford Creek Bore location is a localized depositional high. The Mount York Claystone does not occur in the bore. A reddish brown claystone outcrops 80 feet above the level of the top of the bore and can be traced upstream several miles, where it can be cor- related with the Mount York Claystone in several stratigraphic sections measured as a part of this study. The lithology is medium- to coarse-grained quartz lithic sandstone. Quartzose sandstone ROBERT H. GOODWIN is rare in this member. Lenticular claystones and shales are common and range up to 3 feet in thickness. The sandstones are often cross- stratified. The bedding is usually massive and the matrix is rich in clay minerals which tend to render the sandstone friable. Quartz pebbles up to 1 inch are common. Ironstone concretions are prevalent, however they are not as abundant as in the Banks Wall Sandstone Member. Goldbery (1966) postulated a rapid thinning of this member in the Katoomba-Blackheath area ; however, this characteristic has not been substantiated by the present study. It would appear that Goldbery correlated the ‘“ Unnamed Claystone Marker Bed” at Kanimbla Valley, Megalong Valley, Narrow Neck Peninsula, Scenic Hill and Victoria Pass, with the Mount York Claystone along the western edge of the area covered by his study. Mount YORK CLAYSTONE MEMBER The Mount York Claystone is a reddish brown claystone which occurs as a single bed or two closely spaced beds with a thin sandstone bed separating them. It occurs between 340 and 400 feet above the base of the Grose Sandstone and crops out continuously in the western Blue Mountains. The claystone ranges from reddish brown, mottled or white to light grey, although it is unusual for the claystone to persist more than 100 yards without some red coloration being present. Along the Kedumba Walls the Mount York Claystone outcrops close to the top of the cliffs and occasionally, because of irregularities in the height of the cliffs, outcrops on the surface of the plateau. BANKS WALL SANDSTONE MEMBER The Banks Wall Sandstone is the uppermost member of the Grose Sandstone in the Blue Mountains. Because of the absence of the Burralow Formation west of Hazelbrook, it is not possible to assign a definite thickness to this unit although it is in the order of 350 feet. At Euroka Trig, which was the only place where a full section was measurable, the thickness is 325 feet ; however, it is not known if this value is typical. Goldbery (1966) reports a maximum thickness of 370 feet in the Upper Grose Valley. The Banks Wall Sandstone crops out along the surface of the plateau from Lawson to Katoomba and comprises the surface outcrop of the plateau as far south as Lake Burragorang. It also crops out further east in the major river _ valleys, the most notable being Erskine Creek. WOURNAL ROYAL SOCIETY N.S.W. GOODWIN PLATES I-II Unnamed claystone marker bed on Narrow Neck Peninsula. ee ME Bs Unnamed claystone marker bed, Wentworth Falls. Note erosional notch, 143 TRIASSIC STRATIGRAPHY—BLUE MOUNTAINS, NEW SOUTH WALES oH wOOUBNITI \ \ \ / 7 / rhe / / / / hors x. | \ Ps \ 3/7 = 7 \ m/ |e Sy - os \ ° 2 ‘ OG AWAWALNI YNOLNOD 3 [8 — A ~ VY ee Noe i, uw oA ee \ "ey are 70 >) 4 “ ae fay! 5 ()) \ eT eye) | OSG \ | | | \ eal VENOOIV Ye vo, eas \ a4 . | / 0404s000M \ 3 \ as ae \ a notes \ ea eee / \ &) a Ce uaa!” me a) aw X Son ae \ ( \ - / J ‘ yi / — aie Zz Soom owas es | / y, \ ] wavanxovre & ie 9 b 2 Cl y; S311W Ni 37V9S ‘quojsputs peofy O¥Oj-ering jo dew yoedos[j—’¢ ‘s14 bk Ae pill As J 144 The sand is quartzose with a small percentage of lithic fragments. The percentage of lithic material in the sandstone increases towards the base. Cross-stratification 1s common, as are ironstone bands, which are usually oriented sub-parallel or at random to the bedding planes. Lenticular claystones occur throughout the sandstone and increase in abundance toward the base. Burralow Formation The Burralow Formation is the uppermost unit of the Narrabeen Group. The Burralow Formation is overlain by the Hawkesbury Sandstone and underlain by the Grose Sandstone. The lithology of the Burralow Formation consists of fine-grained micaceous sandstones, claystones and shales. Full sections of the formation are rare and outcrops are generally poor due to the occurrence of talus slopes. The formation has a high percentage of sandstone ; however, due to the nature of outcrop, it was not possible to distinguish the Tabarag Sandstone Member described by Crook (1956). The extent of outcrop (Figure 4) closely approximates that of the overlying Hawkesbury Sandstone (Figure 6) and the variations in thickness are proportionate. In the Mulgoa No. 2 bore on the eastern edge of the study area the thickness is 400 feet, while in the Kurrajong Heights No. 1 bore to the north and east of the study area a thickness of 540 feet was recorded. From the eastern boundary of the Blue Mountains, the Lapstone Monocline, the Burralow Formation increases in grain size and sand content in a westward direction. At the western edge of outcrop near Hazelbrook, the Burralow Formation is indistinguishable from the Grose Sandstone. This change in facies (Figure 5) makes recognition of the Burralow Formation difficult towards the western edge of outcrop and where definite recognition was impossible the strata have been mapped as Grose Sandstone. The micaceous character of the sandstones is persistent throughout the entire area of outcrop. On the eastern part of the study area the formation is composed of numerous claystone shale and siltstone bands, alternating with fine- to medium-grained micaceous quartz-rich sand- stones with only a few lithic fragments. Toward the west the argillaceous bands become less frequent and the sand becomes medium- to coarse-grained and sub-lithic in_ character. Cross stratification is rare in the Burralow Formation and reddish-brown claystones are completely absent. ROBERT H. GOODWIN Narrabeen Group-Hawkesbury Sandstone Boundary A number of criteria for the recognition of a Narrabeen Group-Hawkesbury Sandstone boundary have been proposed by Standard (1961, 1964), Galloway (1965, 1967) and Goldbery (1966). The main field criteria used during this study to distinguish the Hawkesbury Sandstone from the Narrabeen Group (Figure 1) were: (1) The lithological change in character of the sandstones from a quartzose nature in the Hawkesbury Sandstone to a sub-lithic and then to a quartz-lithic nature within the Narrabeen Group. (2) The occurrence of a coarse quartz con- glomerate at the base of the Hawkesbury Sandstone. In the eastern portion of the study area the occurrence of this con- glomerate horizon is quite consistent. The pebbles, ranging up to 2 inches in diameter, consist of quartz and are cemented by silica. The thickness of the conglomerate is variable, the maximum thickness recorded being 10 feet 6 inches at Linden Tank. The increasing frequency and size of the quartz pebbles in the Hawkesbury Sand- stone as the conglomerate horizon and the base of the Hawkesbury Sandstone is approached. This observation may be useful for the examination of a large stratigraphic interval as no true marker beds exist within the Hawkesbury Sand- stone. (4) The fine-grained micaceous nature of the sandstones and the regularity of the interbedded shales and claystones of the top of the Burralow Formation over the eastern portion of the study area. The lateral lithofacies change in a westward direction to a medium-grained sand makes the differentiation between the Burralow Formation and the Hawkesbury Sandstone difficult. On the western margin of outcrop of the Hawkesbury Sandstone the only possible distinction is the slightly more lithic character of the Narrabeen Sandstones. (5) The increase in clay content, as matrix, of the Narrabeen sandstones. This change is relatively abrupt and distinctive in the eastern portion of the area; however, approaching the westward limit of outcrop of the Hawkesbury Sandstone the clay content of the Hawkesbury Sandstone increases and this characteristic is no longer useful for distinction. Sc 145 TRIASSIC STRATIGRAPHY—BLUE MOUNTAINS, NEW SOUTH WALES gon WOOUENT) ~ _—™~ aoom9 ludS 7? UOT} eULIOT moypering jo deur yoedos]—'f ‘o14 TWAYSLNI YNOLNOD VaNnoolVN QyO04000M 7 \ \ \ ae aaa | a es | 3 v ] | (0) / aw SaqiW INI. aavos 146 ROBERT H. GOODWIN LEGEND SANDSTONE SHALE CLAYSTONE (ea) TALUS LOCATIONS 1. Queens Road - Hazelbrook 2. Burgess Falls -Hazelbrook 3. Fairy Falls —Woodford Fic. 5.—Stratigraphic cross-section Woodford to Hazelbrook. 2400 2300 2200 2100 2000 1900 1800 1700 1600 147 TRIASSIC STRATIGRAPHY—BLUE MOUNTAINS, NEW SOUTH WALES ‘quojspues AinqsoxymMepY jo dew yoedos]—'9 “oI \ \ } 7 4 7 x / / / / | | \ \ \ Nia o/|2 2/}|o m / IMI SY 9 \ A z VI3u5 \ ,OO|l VANHSLNI YNOLNOD 5 \ . a] 13 \ A s} |; | 5 0 9 \ \ z / 5. . } fo SA soa y \ A 4° ° 7(/ om % ee \ ZN 4 ° ° ) SS \ % Ss fe) 0 ° x wo \ fe) o \ \ = ( \ | x \ —~\ . \ \ \ eo \ oe | 1 ee o } WK Nr 3 oy 040F8 / e200 \ = a ee ye \ ie ees i ae E ‘\ O¥O4I000M ee ae ae ee é © | ie Eanes \ eae : is me en % N a, = aa \ v \ +22 on Pile \ - \ are i, R ig ee \ Sra a ye \ \ : se =~ V3 1c \ \ ™ \ =< / j a i f OOOMONiUa ey OO Le” | / \ Vi | gt eh Ae ict a \ ~ v 2 SL ee ee SS \ | S371W NI 31v2s 148 In the eastern portion of the area under consideration the recognition of the boundary is not difficult. The Burralow Formation is quite distinctive and can be easily recognized in conjunction with a quartz conglomerate horizon at the base of the Hawkesbury Sand- sandstone, © As the western “extent of) the Hawkesbury Sandstone (Figure 2), just east of Lawson on the Great Western Highway, is approached, the lateral lithofacies change of the Burralow Formation and the disappearance of the conglomerate horizon makes the distinction tenuous. Hawkesbury Sandstone Within the study area the Hawkesbury Sandstone attains a maximum thickness of 760 feet in the Mulgoa No. 2 Bore. The Hawkesbury Sandstone is overlain by the Wianamatta Group and underlain by the Burralow Formation of the Narrabeen Group. With the exception of a few isolated outliers of shales of the Mittagong Formation and the Ashfield Shale (Wianamatta Group), the Hawkesbury Sandstone outcrops at the surface of the plateau from the Lapstone Monocline as far west as Hazelbrook. The Hawkesbury Sandstone thickens rapidly near the western edge of outcrop (Figure 6) and continues to thicken gradually in an easterly direction. A typical hand specimen of Hawkesbury Sandstone is a white to light brown, medium to coarse-grained sandstone. The sandstone is usually poorly sorted and often iron-stained, although concentrations of iron in the form of bands is uncommon. The matrix of the sandstone is made up of clay minerals, mainly kaolinite, and where iron-staining is absent the sandstone is quite friable. Commonly the sandstone is highly cross-stratified, although thick sequences occur where this is not apparent. Quartz pebbles up to 2 inches diameter commonly occur, particularly toward the base of the sandstone. Lenticular clays and shales, although not common, range in thickness up to 11 feet. Only one occurrence of a siltstone was noted in the Hawkesbury Sandstone, this being in a road cutting on the Great Western Highway west of Linden. (Received 15 ROBERT H. GOODWIN Acknowledgements The author wishes to acknowledge the help of the teaching and technical staff of the School of Applied Geology, University of New South Wales, who gave assistance at various stages in the course of this study. In particular, thanks to Dr. J. C. Standard of the University of New South Wales, and to Dr. D. F. Branagan of the University of Sydney, who read and helpfully criticized the manuscript for this paper. References BooKErR, F. W., 1957. Studies in Permian Sedi- mentation in the Sydney Basin. Tec. Rept. Dept. Mines, N.S.W., 5, 10-62. Crook, K. A. W., 1956a. The Geology of the Kurrajong-Grose River District. Unpub. M.Sc. Thesis, Univ. Syd. Crook, K. A. W., 1956b. The Stratigraphy and Petrology of the Narrabeen Group in the Grose River District... J, Proce” oy seSaqgnaenisi = 90, 61-79. GaLLoway, M. C., 1965. The Geology of an Area covered by the St. Albans, Mellong and Mount Yengo..One Inch Series Maps.” Unpub; Msc: Thesis, Univ. Syd. GaLLoway, M. C., 1967. Stratigraphy of Putty-Upper Colo Area, Sydney Basm. J. Prar wire) sec. N.S.W., 101, 23-36. GOLDBERY, R., 1966. The Geology of the Upper Blue Mountains Area. Unpub. B.Sc.Hon. Thesis, Univ. N.S.W. GoopwIin, R. H., 1968. Studies in Stratigraphy and Sedimentation in the Blue Labyrinth, New South Wales. Unpub. M.Sc. Thesis, Univ. N.S.W. HANLON, F. N., OSBORNE, G. D., and RaaeGatTtT, H. G., 1953. Narrabeen Group: Its subdivisions and correlations between the South Coast and Narrabeen-Wyong district. J. Proc. Roy. Soc. N.S.W., 87, 106-120. HELBy, R., 1961. Contributions to the Geology of the Lower Burragorang District. Unpub. M.Sc.(qual.) Thesis,” Univ: Syd: McELrRoy, C. T., 1962: Series. Buy. Min. 1, 56-65. OsBORNE, G. D., 1948. A Review of Some Aspects of the Stratigraphy, Structure, and Physiography of the Sydney Basin. Pyoc. Linn. Soc. N.S.W., 13S UNG SOOKE RaccaTt, H. G., 1938. Evolution of the Permo- Triassic Basin of East Central N.S.W. Unpub. D.Sc. Thesis, Univ. Syd. STANDARD, J. C., 1961. A New Study of the Hawkes- bury Sandstone: Preliminary Findings. J. Proc. Roy. Soc. N.S.W., 95, 145. STANDARD, J. C., 1964. Stratigraphy, Structure and Petrology of the Hawkesbury Sandstone. Unpub. Ph.D. Thesis, Univ. Syd. Sydney, N.S.W., 1: 250,000 Resour. Aust. Explan. Notes, January 1969) Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 149-156, 1969 Granitic Development and Emplacement in the Tumbarumba-Geehi District, N.S.W. (ii) The Massive Granites BriANn B. Guy Depariment of Geology and Geophysics, The University of Sydney, Sydney, N.S.W., 2006 ABSTRACT—-The massive granites of the Tumbarumba-Geehi district may be classified into three groups—the Khancoban, Mannus Creek and Dargals granites—on the basis of spatial distribution. The emplacement of Khancoban and Mannus Creek granites post-dates the regional metamorphism of the district although mineralogically and chemically such rocks bear some similarity to the foliated Cooma-type granites that are considered to have been produced in the regional metamorphic processes (Guy, 1969b). Chemically such massive granites have high CaO and Na,O contents and are considered to have developed either at the same time as the foliated granites or by a regeneration of such granitic material. The Dargals granites are leucocratic with more than 80% normative Q+Or+Ab. It is considered they have migrated far from their position of origin, but may have been produced during the cycle of development of the other massive bodies. Introduction Associated with the Ordovician metasediments of the Tumbarumba-Geehi district, N.S.W. (Guy, 1969a) are several groups of granitic* bodies. These granites are essentially either foliated or massive, the former—the Cooma-type granites (Guy, 1969b)—being associated with the regional metamorphics, while the massive granites post-date the metamorphism, super- imposing contact influences on the country rocks. This paper is concerned with the development and emplacement of the massive bodies. These may be subdivided into three groups (viz. the Khancoban granite, the Mannus Creek granite and the Dargals granite) on the basis of spatial distribution (Guy, 19692). Khancoban Granite The Khancoban granite is a poorly exposed mass outcropping over some 100 square kilo- metres. Associated with it is a small body (4 sq. km.) at Mt. Youngal (G.R. 278.9-134.5)+ near Geehi. Contacts with the metasediments are sharp and nearly vertical, while the mass transgresses regional metamorphic zones (Guy, 1969a) with a relatively narrow contact aureole developed. Within the body, acid to basic * The term “‘ granite ”’ as used in this paper includes all acid plutonic rocks unless otherwise stated. + Snowy Mountains Authority grid reference. dyke rocks are common, especially in the northern section, as well as north-east trending shear bands being prominent—presumably due to the influence of the Yellow Bog-Khancoban thrust (Cleary e¢ al., 1964). The granite is medium- to coarse-grained with no apparent change in grain size marginally. Although generally massive, a weak but definite north- south foliation is evident, particularly in exposures along the Swampy Plains River. Compared with the Cooma-type granites, there is a notable paucity of aplitic and pegmatitic phases in the mass. Inclusions are limited throughout the body, however, along sections of the Swampy Plains River, clusters of pelitic to psammitic xenoliths have been observed. MINERALOGY AND PETROLOGY Most of the granitic phases in the body are strictly granodiorites, being coarse-grained and more leucocratic than the Cooma-type granites, although biotite is often as high as 12%. The general grain size is 3-5mm., with alkali feldspars in places to15 mm. The larger alkali feldspars are optically monoclinic with A values generally in range 0:20-0:35, although there is notable variation throughout the body. 2Vx=75-80°. These feldspars, frequently poikilitic enclosing plagioclase and biotite, have fine perthite lamellae developed. From the 150 one analysis of the Khancoban granite available (spec. 21817) the bulk composition of the alkali feldspar is estimated at Org, 4), assuming minor amounts of sodium in the micas present. The plagioclases have a bulk composition of An,;* with normal zoning from An,, to Ang. In some sections of the body the average composition of the plagioclases is as low as Ang. The plagioclases frequently display an accumulo- phyric effect (see Plate 1 (a)) which is more evident in marginal sections of the body. Such plagioclase clusters are composed of some 20 to 50 small laths, all having approximately the same orientation. The plagioclase also displays “patchy ’’ zoning (cf. Guy, 19695) with some areas of the feldspar at slightly different optical orientation to the host. Biotite forms subhedral crystals with Z=dark brown to dark olive-brown and y=1-645, 2V,x=3-7°. Alteration of this mineral to chlorite and epidote is common. Muscovite is subordinate and where present is in large ragged blades cross-cutting grain boundaries of other phases. Opaque oxides and apatite are accessories. The small granodiorite body at Mt. Youngal is somewhat similar texturally to the main Khancoban granite. Hornblende is common with X=pale brown-yellow, Y=dark olive- green and Z=sea-green. 2V x=50-55° and Z’*c=25°. Biotite with ~=1-650 and Z—dark yellow-brown or green-brown is also a prominent phase. Plagioclase is somewhat more calcic (average An,,) than in the Khancoban granite. Chlorite and epidote are developed at the expense of the mafic minerals. Inclusions within the Khancoban granite have granoblastic textures with some orientation of micas. Grain sizes average 0°5mm., with subhedral porphyroblasts of plagioclase to 2-3mm. The plagioclase (Ans,) has weak diffuse zoning. Biotite occurs as small flakes with. Z—olive-gteen and y— 176405) Tite structural formula of an analysed sample (spec. 21815) is (Ky-93 Nap-a5 Cag-o5)(Alo-20 Tinos Fe2q, Fett, Mro-o1 Mo-98) (Sig-74 Aly-26)O19 (OH) >. The pronounced green colour of the biotites is in contrast with those biotites in the granitic phases and those in the inclusions of the Cooma- type granites (Guy, 19695). An analysis of the host rock of the biotite is noted in Table 1 (No. 3). * Compositions of the plagioclase were determined from the extinction angle X~\(010) | [100] measured ona universal stage and referred to the low-temperature determinative curves of Bordet (1963). BRIAN B. GUY TABLE 1 Chemical Analyses, Barth Mesonorms and Modes of Rocks from the Khancoban Granite Oxide 1 2 3 SIO; ine 73-26 70-20 69-82 1iO; 0-24 0-26 0-90 Al,O, 12-79 15-83 13-13 Hes®. 0-47 \3-04 0-71 FeO 1-90 3-59 MnO 0-08 0-08 0-08 MgO 0-62 0-75 1-49 CaO 2-28 2-87 3°84 Na,O 3°77 2-97 3°31 K,O 4-23 3°57 1-88 P.O; 0-03 — 0-07 EO 0-46 -—— 0-81 H,O- 0-06 — 0-13 Total 100-19 99-57 99-76 O 28-64 31-40 34°37 Or 23°17 15-75 3°50 Ab | 34-25 27-15 30-60 An 5-55 13-60 15-87 Cran _ 2°37 — Bi 3°39 9-20 12-72 Act —- — 0-08 Di 3°92 a -— Ap 0-05 —- 0-16 aie 0-51 0-51 1-95 Mt 0-49 ~- 0-76 Ouartz ae 36-0 35-40 41-1 K-feldspar 21-0 30-35 — Plagioclase 34-7 20 38-1 Biotite >. 8-3 7. 17-3 Muscovite — 2 0-8 Chlorite .. — — 0-4 Epidote .. — 1 2°3 1. Spec. 21817, granodiorite, G.R. 281.8—-146.0 (3 km. south-east of Khancoban). Anal. B. Guy. 2. Spec. Kh-1, adamellite, Kolbe and Taylor (1966). 3. Spec. 21815, psammopelitic inclusion, G.R. 279.2-139.8 (11 km. south of Khancoban). Anal. B. ‘Guy: CHEMICAL DATA Only one new analysis is available for the Khancoban granite, and this is presented in Table 1 together with an analysis of an inclusion from the body, and another analysis of the Khancoban granite from Kolbe and Taylor (1966). The granite analyses indicate higher CaO contents than for the Cooma-type granites (Guy, 1969b) and Na: K ratios slightly greater than unity. No amphibole has been recorded in the main phase of the Khancoban granite, but normative diopside occurs. The chemical data are summarized in Figs. 1 and 2 (a). WOORNAL ROYAL SOCIETY N.S.W. GUY PLATES Wa PEALE lita) Section of a plagioclase from Khancoban granite (spec. 21817). The plagioclase consists of numerous small crystals all of which display some zoning. Crystal near extinction position. (x 45.) PEATE PE) Section of zoned plagioclase from Munderoo granodiorite (spec. 21840). Note development of patchy zoning. (x 45.) GRANITIC DEVELOPMENT AND EMPLACEMENT CaO = —22_ Na,0+K 20 Fic. 1—Plot of Khancoban (K), and Dargals (D) granites on a CaO —Na,O-+ K,0 —FeO + MgO + MnO diagram. Dashed line indicates variation displayed by Cooma-type granites and solid line the variation for Bathurst granites. Murrumbidgee-type granites generally lie between these two curves. (After Vallance, 1967.) FeO+MgO+MnO Mannus Creek (M) It is interesting to compare the analysis of the inclusion with those of the Cooma-type granites since all the inclusions may be derived from rocks similar to the surrounding meta- sediments (Guy, 1969a). The Na: K ratio is high (2-67) while the Fe : Mg+-Fe ratio is also high (0-56). Mannus Creek Granite In the vicinity of Mannus Creek, a small {ca. 64 sq. km.) granite complex occurs sur- Q 151 rounded by a contact aureole 1-6 km. wide. This complex constitutes the Mannus Creek granite which varies in composition from leuco- cratic adamellites to hornblende-rich grano- diorites. To the west of the area mapped this mass intrudes the Corryong granite. Three major units within the Mannus Creek granite have been recognized (Fig. 3), viz. the Bogandyera granite, the Munderoo granodiorite and the Prison Farm_ granodiorite. The Bogandyera granite is typically fine- to medium- grained, in places porphyritic in quartz and feldspar. It is usually a granite (sensu stricto) or an adamellite. The Munderoo granodiorite is medium-grained with biotite the only mafic phase and is a heterogeneous unit having gradational boundaries with the other units. The attitude of the granite-sediment contact is variable but generally steep, with some shallowly dipping contacts to the north of G.R. 270-170 suggesting the mass exposed may be near the roof of the complex. All the granitic rocks in this suite are massive and devoid of any directional structures. Apart from some hornblende-rich inclusions in marginal phases of the Prison Farm granodiorite xenoliths are not common, while aplitic and pegmatitic rocks are restricted. MINERALOGY AND PETROLOGY The Bogandyera granite has an average grain size of 0-6 mm. with numerous small subhedral phenocrysts mainly of quartz and alkali feldspar. Marginal phases are markedly finer grained. The Munderoo granodiorite has a grain size of 2-3 mm. with occasional phenocrysts of alkali Q (b) Ab Or Fic. 2—Projection of Q—Or—Ab—An system at PH.0 =2,000 bars, indicating cotectic curves for Ab: An ratios of 1-8 and oo and the maximum melting points (o) for various Ab: An ratios. (After Von Platen, 1965.) (a) Khancoban (+) and Mannus Creek (x) granites, with Ab: An ratios indicated. (6) Dargals (x) granites with Ab: An ratio indicated. 152 TABLE 2 Chemical Analyses, Barth Mesonorms and Modes of the Mannus Creek Granites Oxide i 2 3 5103 fe TL-68 70-60 65-49 iO; 0-47 0-30 0-59 Al,O, 13-06 14-75 14-69 Fe,O, 0-70 0-59 oa) FeO 2-51 2-13 4-13 MnO 0-10 0-12 0-13 MgO 0-85 0-82 1-92 CaO 1-99 2-95 4-79 Na,O 3-92 3-21 3°07 K,O 4-59 3-28 2-79 1EOs 0-09 0-10 0-10 H,O+ 0-39 0-73 0-87 H,O- 0-05 0-07 0-04 Total 100-40 99-65 | 99-98 QO 24-58 31-87 24-83 Or 25-05 15-28 10-07 Ab 5-45 29-50 28-25 An 4-52 13-25 18-48 Ce: == Le 3 — Bi 3-68 7-31 10-85 ‘XGL 4-80 — 4-58 Ap 0-19 0-21 0-21 Ti. 0-99 0-66 1-26 Mt 0-73 0-63 1-47 Quartz 27°2 34-6 25-7 K-feldspar 40-0 14-0 2°5 Plagioclase 20-8 38°5 46-8 Biotite: ~: 6-8 10-8 14-6 Hornblende 4-8 — 10-0 Accessories 0-3 2°2 0-5 1. Spec. 21831, Bogandyera adamellite, G.R. 271.1-167.4 (10 km. north-west of Tooma). Anal. B. Guy. 2. Spec. 21814, Munderoo _ granodiorite. G.R. 269.0-175.9 (1 km. east of Mannus). Anal. B. Guy. 3. Spec. 21836, Prison Farm granodiorite. G.R. 271.3-173.1 (8km. south-west of Tumbarumba). Anal. B. Guy. feldspar and quartz attaining 5-7 mm., while the Prison Farm granodiorite is even-grained (1-2 mm.). Quartz phenocrysts of the Bogandyera granite are ragged and appear somewhat resorbed. The alkali feldspars are generally optically triclinic with A values >0-50. The bulk composition of the feldspars, as estimated from modal and chemical data, and assuming compositions for the micas, is estimated to be in the range Or;, to Or,;. This is exclusive of the Prison Farm granodiorite ; it contains only minor quantities of this feldspar. Fine string perthite lamellae may be present in these rocks. Plagioclases are subhedral BRIAN B. GUY with normal euhedral zoning. Granitic members of the complex have plagioclases from An,, to Ang, while in granodioritic phases the plagio-_ clases have cores of An,, and occasionally Ang, (cf. Snelling, 1960, p. 194). As noted in the Khancoban granite, some plagioclases display an accumulophyric effect, with patchy zoning also developed (Plate 1 (b)). Biotite is present as ragged grains with Z=dark olive-brown (nearly opaque) and y=1-650. This mica is often associated with, and sometimes replaces, horn- blende. Hornblende is euhedral to subhedral but in the Bogandyera granite occurs as small ragged grains exhibiting a glomerophyric texture. All hornblendes have X=light brown, Y=medium brown-green, and Z=blue-green, with zoning from a brown core to green margin, Z’~c=23-25°, and 2Vx=65°. Chlorite, epidote and muscovite appear as alteration products, while apatite and zircon are accessories. Inclusions within this granitic complex are generally restricted to the Prison Farm grano- diorite, and consist of quartz, optically mono- clinic alkali feldspar, plagioclase (average An,;), biotite and hornblende. Most of the phases are similar optically to those observed in the host rocks. CHEMICAL DATA Analyses of granitic rocks from this complex are presented in Table 2. Chemical data are summarized in Figs. 1 and 2 (a). The group as a whole displays lower SiO, and AI,O, contents than the Cooma-type granites but are similar to the Khancoban granite. CaO, N,O and the Na: K ratio are higher than for the Cooma-type granites. The Munderoo grano- diorite shows some chemical similarity to the Cooma-type granites (but compare Fig. 1). It may be significant that mineralogically and texturally (e.g. grain size, clustering of micas) the Munderoo and Cooma bodies are not dissimilar. Further field work to the west of the area noted in Fig. 3 may establish significant information regarding the relationship of the Munderoo granodiorite to the Cooma-type granites. Dargals Granite The Dargals granite outcrops over some 230 sq. km. and is generally a rather deeply weathered medium-coarse-grained leucocratic granite. Along its western margin, near the Tooma River, a fine-grained variety pre- dominated, in which mafic minerals constitute several percent of the rock. In such cases GRANITIC DEVELOPMENT AND EMPLACEMENT LEGEND (<) Tert-Recent Alluvials EEE Tertiary Basalt METASEDIMENTS (I Knotted Schist Zone {IL Bictite Zone MM] Chlorite Zone fara Hornfelsed GRANITES [Xx] Corryong Granite [+ +} Bogandyera Granite [=E] Prison Farm Granodiorite (“i Munderoo Granodiorite Fic. Scale in kms 3—Distribution Mannus Creek Granite y*4 ) Na Wf Le H soy Nt eteeeeeeit SAYS 7 XS AEN Ste eet aeien gt! 7 (oe settee py Ste te eee teary ft Tt +44 + i} 170 t + + +++ 4444 +e tlt et4+ Hp At up. t+teeeeegee te VC. ae fe ++ treet st + +++ RN teeter ety t+eeeteetst $e eeeee te RX ie “ x XxX xX X Mek KX PER KS XE Eo X x KX KK Kw KX KX RK Xx Se x KX KX KX KX KX K K KR KR XK Xe A XK x x eee ee ee Ne ete eeeteeeH: etteeeeeete eH: terrae sere ee A +t ee tee eee tT +e eeeeteett ; Veeereteet etek te eeeteeeetst ieee ee ee Ne oe aa as tee Pet Ppa Hy eh ee te ett aa kb ete eetgetegteee te Het te eee et teeters Ate eee ee eee ee tt Atte eeteeeeeeeee Atte ee eeteet et \tteet +4: ++ ttt ee +eHettete +eHteteest ++i tte +Hrteet Nee a th, M+ + + 418 see ee x x x Pad x x e Tumbarumba x x x x x x x Me x Kx HX KK KK x x K x x x x x x x x x x x 4 x x — x x x x eS x x x > * x oa oO x x ae x x aN D x » Ss x x x x 153 of Mannus Creek granites, south of Tumbarumba, referred to S.M.A. grid. 154 outcrops are more pronounced and a distinctive flora (conifers) is present. In the vicinity of the Big Dargal (G.R. 284.0-155.8) the granite is coarse-grained with megacrysts of subhedral alkali feldspars and occasionally quartz. The Dargals granite is massive throughout and well jointed. Aplitic veins are common, pegmatites less so. Included country rock material is virtually absent, while a prominent exogenous contact zone is developed. Towards the north- east this mass intrudes another granite similar to the Khancoban granite (see Guy, 1969a, Fig. 2), however, no detailed examination of this area has been made. The Pine Mountain granite and the Mt. Mittamatite granite (Edwards and Easton, 1937) some 25km. to the west of the Dargals granite are remarkably similar mineralogically and chemically to the Dargals granite. Small masses at the Granite Knob (G.R. 286.0-114.0) and at Biggera (G.R. 271.0-144.0) may belong to this group. MINERALOGY AND PETROLOGY The medium-grained phases of the granite have an average grain size 2-3mm., while finer sections average 1-0 mm. Perthitic alkali feldspars are common as subhedral megacrysts up to5mm. A values average 0-25 for small grains and 0-40 for larger grains, the latter with 2Vx=70°. Assuming that the micas contain no sodium and that the alkali feldspars contain about 49% An, the composition of these feldspars may be estimated as Org, from modal and chemical data. Biotite is ragged with numerous small crystals occurring near the ends of, and having the same optical orientation as the larger laths. For these micas Z=—dark olive- brown and y=1-657. In the _ porphyritic granite clots of biotite occur (up to 5-6 mm.). These clots are commonly constituted of two varieties, one with Z—dark red-brown and with pleochroic haloes around zircon _ crystals inclusions, the other with Z=mid-green. The latter biotite appears to replace the red-brown biotite. Accessory minerals in the granite include opaque oxides, apatite, zircon and fluorite. CHEMICAL DATA Two rocks from the main Dargals granite have been analysed. The data are presented in Table 3 with an analysis from Kolbe and Taylor (1966). This group of rocks is characterized by high SiO, and low total iron, MgO and CaO reflecting the paucity of mafic constituents. Total alkalis are high while the Na:K ratio is near unity. These granites have a high oxidation ratio compared with BRIAN BUGUY other granitic suites in the Tumbarumba-Geehi district. Chemical data are summarized in Figs. 1 and 2 (0d). TABLE 3 Chemical Analyses, Barth Mesonorms and Modes of the Dargals Granite Oxide 1 2 3 SHOP hieO2 76-74 75-37 iO; 0-10 0-01 0-06 Al,O; 12-02 12453 ved. yes Pees 0-61 0-33 Lo 87 eO 0-61 0-92 f MnO 0-06 0-07 0-06 MgO 0-23 0-18 0-086 CaO 0-65 0-65 0-50 Na,O 3°63 3°35 3-65 K,O 4-79 4-79 4-7] Jee (OP 0-01 0-03 — HOF 0-41 0-48 = 12h Om 0-09 0-10 Total | ; 100-23 100-18 99-1] @) 34:30 | 35-40 33°27 Or 27-70 27-22 26-83 Ab 33-00 30-55 33-05 An 2-40 3°15 2:30 Cu. — Oz 2-14 Bi 1-68 2-56 2-27 Ap 0-14 0-05 — ais 0:15 0-03 0-15 Mt 0-64 0-34 --5 Quartz. | 39-2 36-0 45 K-feldspar 30-4 40-2 15 Plagioclase 27°77 eS el 35-40 Biotite a 2-4 4-0 2 Accessories 0-2 0-1 I 1. Spec. 21821, adamellite. G.R. 283.5—-152.5 (9 km. north-east of Khancoban). Anal. B. Guy. 2. Spec. 21827, granite. G.R. 280.0-158.9 (12 km. south-east of Tooma). Anal. B. Guy. 3. Spec. Ja-l, leucogranite. Kolbe and Taylor (1966). Discussion on the Origin of the Granitic Rocks It is not uncommon to find an association of granite types in south-east Australia and it has been claimed by Browne (in David, 1950) that such rocks may be classified into one of the following groups: (i) Ordovician (gneissic granites associated with regional metamorphics), (ii) Silurian (foliated granites with little meta- morphic influence), and _ (iii) post-Silurian (massive granites). Joplin (1962) has postulated that granitic rocks cannot be assigned to definite orogenic periods on the characteristics suggested by Browne. She claims that the granitic rocks of south-east Australia may be classified GRANITIC DEVELOPMENT AND EMPLACEMENT according to their position in the Tasman geosyncline which influenced eastern Australia during the Palaeozoic (see Packham, 1960). Joplin correlates granitic type with time, place and tectonic development in relation to the orthogeosyncline, and also to “intensity of movement during emplacement’’ (cf. Read’s 1955 “granite series’’). Vallance (1967) has also recognized granitic groups in south-east Australia and refers to such as “‘ Cooma-type ’’, “Murrumbidgee type’”’ and “ Bathurst type ”’. He has pointed out that each group of granites displays markedly different chemical character- istics, and this may be illustrated when analytical data are plotted ona “CaO —Na,O0+ K,0 —FeO+Mg0+Mn0O (wt. %) ”’ diagram. Vallance suggests that the relatively high CaO contents of the Murrumbidgee and Bathurst type granites may be related to a varying and locally increasing (perhaps through vulcanism) basaltic component of the crust during geological time. This explanation would not be applicable to the various granitic types of the Tumbarumba-Geehi area as all such bodies are at present localized in a _ non-volcanic Ordovician terrain. However, it is possible that the massive granites have originated at greater depths than the Cooma-type granites, possibly in sections of the crust adjacent to basaltic rock types. Several salient points may be emphasized concerning the relationship of the massive granites in the Tumbarumba-Geehi area. The Khancoban and the Mannus Creek granites bear some similarity to the Cooma-type granites, while the Dargals granite and the Pine Mountain granite (Edwards and Easton, 1937) are petro- graphically and chemically distinct. Discussion on this latter group is deferred (see p. 156). The Khancoban granite displays a weak but discernible secondary foliation yet clearly is not directly connected with the regional meta- morphism, superimposing some contact influence on the country rock. This granite, then, probably post-dates the foliated Cooma-type granites, but may have been emplaced while the regional stress field was still active. The petrographic similarity of the Mannus Creek, Khancoban and Cooma-type granites is evident in that the plagioclases have calcic cores and patchy zoning. Chemically these massive granites differ from the Cooma-type granites in that the former have higher CaO and Na,O contents. Total iron and magnesium contents do not differ markedly (cf. Snelling, 1960 ; Vallance, 1953). The possibility that the massive granites have developed either as a continuation of the 155 regional processes involved in the formation of the Cooma-type granites or a later regeneration of ‘‘ Cooma-type material ’’ must be examined. Some light may be shed on the problem by the investigations of Von Platen (1965) on the system Q—Or—Ab—An at Py,o=2000 bars. Although recent studies by Weill and Kudo (1968) have placed some serious doubt on the validity of the minimum melting points in this system, as determined by Von Platen, the latter author’s result may indicate satisfactorily the trend of a minimum melting point with variation in Ab: An ratio. In an explanation of the development of the Cooma-type granites, it was suggested (Guy, 1969b) that such rocks formed by (a) accumulation of CaO in high- grade metasediments together with a segregation into quartzo-feldspathic and mica-rich sections, and (b) accumulation of Na,O coupled with a breakdown of micas resulting in the formation of alkali feldspars. It was suggested that not all Cooma-type granites had undergone to the the same degree the processes outlined. Those granites which had undergone both (a) and (6) processes lay in a field on the “ Q-side”’ of the cotectic in the system Q—Or—Ab—An, while those in which there had been limited breakdown of micas lay on the “ plagioclase side’ of the cotectic. It may be noted that the distribution of the massive granites is well into the plagioclase field. Thus if the Khancoban and Mannus Creek granites represent highly mobilized meta- sediments or regenerated Cooma-type granites, then it is unlikely that such rocks would have undergone stages (a) and (b) outlined above for the Cooma-type granite development, as fluid or “‘ host-rock ’’’ phases would tend to be in the ‘“ Q-field’’. However, such massive granites have higher CaO and Na,O contents than the foliated granites, hence a _ possible sequence of events for the formation of the former granites could be (1) accumulation of CaO and segregation into quartzo-feldspathic and mica-rich sections, (2) mobilization of less refractory portions, (3) accumulation of Na,O in this less refractory section. Of course such segregation in step (1) would not be complete. Kolbe and Taylor (1966) have suggested that the foliated and massive granodioritic rocks from south-east Australia have arisen through (?) complete melting of sedimentary rocks of “ Ordovician clay-rich psammopelites with more normal geosynclinal greywackes and shales ’”’. Although present studies (Guy, 1969a) suggest that “‘ normal greywackes and shales’ are not common in the sequence—most rocks having relatively high K,O:Na,0O ratio and high 156 alumina contents—the geochemical data pre- sented by Kolbe and Taylor is compatible with the proposed process of granitic development. The Khancoban and Mannus Creek granites bear some mineralogical similarity to the Murrumbidgee granites, although chemically some may be similar to Bathurst granite types (see Fig. 2). Other investigators have suggested a somewhat similar origin of other Murrumbidgee type granites from south-east Australia. For instance, Vallance (1953) indicates that the massive to foliated Ellerslie and Wondalga granites may have arisen partly through “a certain ‘rejuvenation’ of the earlier granitic material’’. Snelling (1960) has concluded that some of the acid phases of the Murrumbidgee batholith represent the primary magma type with which there had been contamination to produce the “contaminated granites’ of the Murrumbidgee batholith. The process of development of the Khancoban granite implies that mica-rich phases may develop as a by-product of granitic formation. This may also have undergone a process of sodium enrichment and some of the inclusions in the Khancoban granite (Table 1, No. 3) may be chemically similar to such a by-product. Some of the abundant dyke rocks (Joplin, 1958) of dioritic composition occurring throughout the Snowy Mountain region of N.S.W. also may be a result of such granitic development. The Dargals and Pine Mountain granites are examples of the “ leucogranites ’’ of Kolbe and Taylor (1966) that contain significantly more than 80% Q+Or+Ab. The two analyses (Table 3 (1 and 2)) of the Dargals granite plot near the cotectic line for a specified Ab: An ratio in the system Q—Or—Ab—An (Von Platen, 1965). It is possible that such rocks have been largely fluid at some stage during their development and hence may have migrated far from their position of origin. There is no evidence to suggest any substantial modification of their composition through assimilation of other rock types. Such massive leucogranites may have developed through mobilization of the low temperature melting fraction of the other (and older) granitic suites examined. Acknowledgements I wish to thank Professor C. E. Marshall, in whose department this work was carried out, and Associate Professor T. G. Vallance for BRIAN B. GUY suggesting the study and for criticism and guidance. I would also like to thank Miss J. A. Forsyth for drafting the figures. References BorDET, Pe 1963. Courbes pour la detérmination des feldspaths plagioclases haute température et basse temperature, dans la zone perpendiculaire a g’(010). Bull. Soc. Frang. Minér., 86, 206-207. CLEARY, J. R., DovLe, H. A., AnD Moye, D. G., 1964. Seismic Activity in the Snowy Mountains Region and Its Relationship to Geological Structures. J. Geol. Soc. Aust., 11, 89-106. Davip, T. W. E., 1950. The Geology of the Common- wealth of Austvalia. Arnold, London. Epwarps, A. B., AND Easton, I. G., 1937. Igneous Rocks of North-east Benambra. Roy. Soc. Vict., 50, 69-98. Guy, B. B., 1969a. Progressive and Retrogressive Metamorphism in the Tumbarumba-Geehi District, The Proc. N.S.W. Jj. Proc: Roy. > Secs eNes iyo. Lot 183-196. Guy, B. B., 1969. Granitic Development and Emplacement in the Tumbarumba-Geehi District, N.S.W. (i) The Foliated Granites. om P ree: Roy. Soc. N.S.W., 102, 11-20. Jopiin, G. A., 1958. Basic and Ultrabasic Rocks near Happy Jacks and Tumut Pond in the Snowy Mountains of N.S.W. J. Proc. Roy. Soc. N.S.W., 91, 120-141. Jopiin, G. A., 1962. in the Tasman Geosyncline. 9, 51-69. KOLBE, P., AND Taytor, S. R., 1966. Geochemical Investigations of the Granitic Rocks of the Snowy Mountains Area, New South Wales. /. Geol. Soc. Aust., 13, 1-26. PackHAM, G. H., 1960. Sedimentary History of Part of the Tasman Geosyncline in South-eastern Australia. Rep. 21st Int. Geol. Congy., 12, 74-83. ReaD, H. H., 1955. Granite Series and Mobile Belts. In The Crust of the Earth. Geol. Soc. Amer. Spec. Paper 62, 409-430. SNELLING, N. J., 1960. The Geology and Petrology of the Murrumbidgee Batholith. Q. Jl. Geol. Soc. Lond., 116, 187-217. VALLANCE, T. G., 1953. An Apparent Magmatic Cycle J. Geol. Soc: Aust. Studies in the Metamorphic and Plutonic Geology of the Wantabadgery- Adelong-Tumbarumba District, N.S.W. II. The Granitic Rocks. Pyvoc. Linn. Soc. N.S.W., 78, 197-220. VALLANCE, T. G., 1967. Palaeozoic Low Pressure Regional Metamorphism in South-eastern Australia. Meddr. dansk. geol. Foren., 17, 494-503. VON PLATEN, H., 1965. Genesis of Migmatites. morphism. Ed. by Pitcher and Flinn. & Boyd, London. WEILL, D. F., AND Kubo, A. H., 1968. Initial Melting in Alkali Feldspar-Plagioclase-Quartz Systems. Geol. Mag., 105, 325-337. Experimental Anatexis and In Controls of Meta- Oliver (Received 26 July 1969) AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. 71-79 ARUNDEL ST., GLEBE, SYDNEY, N.S.W., 2037 apie PE: / > bi - : . 2 Wa MAES If Oy Bs, ! pitin yee | ae ¥ 4 sd be ea } y Hin“) | Vice-Presidents a bee " Ke Aa Gimmes = ess x. A. H: Low, ‘Php. Irae sak vee Sey ALH. VOISEY, DSO ee ay oe oA if sites is ‘ sag ee ae "Honorary Seeretaries ue De f M. KRYSKOs v. TRYST (ts), Bese, Grad. Dip. nN oe is Honorary Treasurer es “ Se a es a ae "Plosérary Librarian Lo aay ey yee. WMS Boor Y. a Pe 6 POGGENDOREF, ‘B.se.aer. aN! eee : a “Members of Cound ae Ae i) % ae eae on ce ae be . pede ae M: Aan PUTTOCK, 'B, Sena: A. Inst. = iy 1c... W. H. ROBERTSON, Bsc. | He ei) We BS EE CEE, Ph. D. (8.8.7), M.S A, (594), : DET oh Oo PG (Oxon.). Beds A La Bs L. Raley ah Ph.D ales” Be a 1866, ie ie. sanction of Her Most =e its nme title, and: was euneoeEor ater by. 18 i Ve eee ae ; ributi a Kober ne ae Spreng. on the Far North 0 ae South Mee. eed A. Aula : Bie ag the f ay - \ ir ee e aaa Si icanes St Daas Coal j in the Volcanic Necks near” ae ) : -Goobarragandra Ultramatfic, Belt, N.S. Ww. aT G. Goldie s Radio rbon Datings of Ancestral River Sediments on the Riverine Plain’ of Sout h-eastern, Australia and Their Interpretation. Simon Pels . SS Note on ( Coals. Containing Marcasite Plant. Petrifactions, ‘Yarringa Creek, : srtney: F ne, ee bk ee bic W. Hoge: and A ee Cook «. st of Office Bearers, 1 1968-1969: ee oo eo oe oS HA WeETe & ss : pS ig en ee = 2 a Gec ee blocks. Reférenchs, ~ Societ the text by giving ihe author's S. name. Se he Ad year of publication, eg.: Vick (1984) ; tl the end of the Pau ae ee be © aranged ‘nee geen Sain ‘So aS Be ests - THE AUTHORS OF PAPERS. RE “ALONE RESPONSIBLE OR STATEMENTS MADE AND THE OPINIONS EXPR rhe b he Gh 5 Pi frag coh Ein hy Rt Tee Lye ae , Mt \ frat X- x pe ae Lp tise ent 7s Ky Sh OR an ge ee 23 WEARS ‘ ‘. Ge. See ral ee Pre Se Pat ‘ . : DEY Wee Roy eae Ig eye ae \ i eae ee 5 SNR SE é Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 157-158, 1969 A Solar Charge and the Perihelion Motion of Mercury R. BuRMAN Department of Physics, University of Western Australia ApsTrRacT—The effect of a possible net solar charge on the perihelion motion of Mercury is examined by using non-relativistic mechanics and by using the Reissner-Nordstrom metric of general relativity. (1) Introduction Bailey (1960a, 19605, 1960c, 1965) gave explanations of a number of astrophysical and terrestrial phenomena by postulating the presence of a net electric charge on the sun, on other stars, and on planets; two possible sources for such a charge were suggested. It is thus of interest to discuss the possible effect of a solar charge on the motion of the perihelion of Mercury. General relativity appears to account with an accuracy of about 1% (Dicke and Goldenberg, 1967) for the observed residual advance of the perihelion of Mercury left after planetary perturbations have been accounted for. Various alternative or supplementary explanations have been stiggested from time to time, both before and after the advent of general relativity. For example, it has been suggested (Dicke and Goldenberg, 1967) that some (perhaps 8%) of the observed residual is due to solar oblateness, thus threatening the agreement between general relativity and observation; agreement with theory is then restored by postulating a long- range scalar field. Non-relativistic explanations were discussed by Gerjuoy (1956) ; one of these involves an electric charge on the sun and is considered in Section (2) of this note. If the sun has a net charge of sufficient magnitude, space-time about it will be repre- sented in general relativity by the Reissner- Nordstrom metric rather than by the Schwarz- schild metric normally used: space-time is modified by the charge, which thus exerts a gravitational effect in addition to purely electro- magnetic effects. Perihelion motion in this case is considered in Section (3). (2) The Non-relativistic Effect Suppose that the sun is a sphere with a net electrostatic charge Qe.s.u. distributed i A symmetrically about its centre, and _ that Mercury can be regarded as an uncharged conducting sphere; the charge on the sun induces a dipole in Mercury. Since the distance vy from the sun to Mercury is much greater than both the radius of the sun and the radius a oi Mercury, the force on the planet becomes GMM, 2f%a®Q? Fy) =— al eee ae : Here G is the gravitational constant, while M, and M, are the masses of the sun and of Mercury. The factor f, where 0 20° 21 82 Aspect North 15 22 South 18 BY East 16 25 West 13 21 Tree cover Dense 2 1 Some ll 14 Nil 21 84 Average rainfall <50” 6 11 50-60” 2 5 61-70” 21 20 > 70" 49 65 * Expected percentage of class infested: 16. The expected incidence of crofton weed in each class was estimated on the basis of a random distribution (i.e., equal density over the whole region) of the plant. The influence of each factor on distribution was examined for significance by a chi-square test, comparing observed with expected values in each class. A significant effect of a factor on distribution was taken to be indicated by a probability value of less than 0-05, using the data for all classes within that factor. It has been noted that crofton weed favours frost-free hillside localities such as abandoned banana plantations (Richmond-Tweed Develop- ment Committee, 1966), and that the plant is susceptible to frost (Auld, 1969) and usually absent from flat land (Auld, 1969a). For these BRUCE A. AULD reasons the flat areas of the region were not considered in this survey. Results The percentage of each class infested with crofton weed and the percentage of the total amount of crofton weed which occurred in each class is presented in Table 1. With the exception of aspect, the influence of each factor on distribution was statistically significant (P<0-05). The number of infested quadrats with given slope, degree of tree cover and average annual rainfall was determined by summation (Table 2). TABLE 2 Effect of Interaction of Steepness, Tree Cover and Rainfall on Distribution Number of Quadrats Class Combination with Crofton Weed Present Steep- Tree a ness Cover Rainfall | Observed | Expected <20° Dense <50” 0 i! 50-60” 1 3 61-70” 0 0 >7107 0 1 Some <50” 0 ve 50-60” 0 5 61-70” 0 3 > 70” 5 1 Nil <50” 7 23 50-60” 0 14 61-70” 9 15 >70” 16 10 > 20° Dense <50” 0 5 50-60” 0 22 61-70” 0 1 >70” Z 7 Some <50” 8 11 50-60” 1 8 61-70” 2 2 >70” 14 4 Nil <50” 9 14 50-60” 7 12 61-70” 30 19 710% 98 20 In the sample taken 10% of the region had the following “‘environment’”’: (i) nil tree cover, (ii) land equal to or greater than 20° in slope, and (111) an average annual rainfall exceeding 70 inches perannum. The probability of the occurrence of a significant infestation in this environment was 76%, and indeed 47% of all crofton weed in the area surveyed occurred in such an environment. By including an additional 7% of the region with similar slope and cover, but with a rainfall of from 61 to 70 inches per annum, the occurrence of some 61% of all crofton weed infestations is accounted for. DISTRIBUTION OF EUPATORIUM ADENOPHORUM SPRENG. IN N.S.W. Discussion The preference of crofton weed for areas of nil tree cover may well be associated with the fact that its seeds require light for germination (Auld, 19695), while the small size of the seedlings would presumably limit their initial competitive ability under forest conditions. The observation that this species occurs chiefly in high rainfall areas confirms earlier observations in Hawaii (Ripperton and Hosaka, 1942). The influence of slope on distribution was marked (Table 2). It is considered that slope has been the major physical factor limiting the progress of crofton weed control in the Richmond-Tweed region because areas where slope is equal to or greater than 20° cannot normally be negotiated by wheel tractors, which renders impractical control by normal mechanical treatments or by high volume herbicide application. These physical problems render the cost of reclaiming such areas relatively high. In some cases greater returns may be forthcoming from more intensive development of the flatter portions of properties. The use of crawler tractors rather than wheel tractors is useful in many cases on steep land. However, areas too steep or too rocky to be dealt with in this way still pose a problem. The aerial application of herbicides is not practical because of the danger of drift on to neighbouring horticultural crops, and the results of the attempted biological control of crofton weed have not been very encouraging (Auld, 1969c). These areas of rugged terrain, particu- 161 larly where infestations are scattered, may prove amenable to the use of powder forms of herbicides applied from horseback. Acknowledgements I wish to thank the Weed Inspectors of the Far North Coast County Council for assistance with the field work, and personnel of the Biometrical Branch of the New South Wales Department of Agriculture for the analysis of the data. I also wish to thank Mr. P. Martin, Lecturer in Botany at the University of Sydney, for his advice and criticism. References Survey of Woody Weeds of the Agric. Gaz. N.S.W., AULD, B. A., 1969a. Richmond-Tweed Region. 80, 181. AULD, B. A., 19696. The Ecology of Major Woody Weeds of the Far North Coast of New South Wales. M.Sc.Agr. thesis, University of Sydney. AULD, B. A., 1969c. Incidence of Damage Caused by Organisms which Attack Crofton Weed in the Richmond-Tweed Region of New South Wales. Aust. J. Sct., 32, 163. BLAKELEY, W. F., 1920. Monthly Meetings. Pyroc. 45, 318. McGarity, J. W., 1956. The Soils of the Richmond- Tweed Region. A Study of Their Distribution and Genesis. M.Sc.Agr. thesis, University of Sydney. Richmond-Tweed Development Committee, 1966. Development Report on the Richmond-Tweed Region. Prepared for the Minister for Decentral- isation and Development, Sydney. RIPPERTON, J., and Hosaka, E., 1942. Vegetation Zones of Hawaii. Hawati Agric. Exp. Stat. Buil., 89. Notes and Exhibits at Linn. Soc. N.S.W., Communicated by Mr. P. M. Martin (Received 18 November 1969) Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 163-167, 1969 Chemicals in Food* J. W. G. NEUHAUS All food consists of mixtures of chemicals. These are principally proteins, carbohydrates and fats, with minor proportions of phospho- lipids, sterols, vitamins, minerals and alkaloids, among others. This address is not concerned with the major chemical complexes of food, but rather with the minor components, whether naturally present or deliberately or accidentally added. Our food embraces many plants and animals which contain chemicals with known toxic properties as natural components. Generally, man has learned to avoid dangerous exposure to these components in his food, but under special circumstances, such as unusual con- centration, for example, accidents occur. Acute toxicity, which is frequently recognized and the source subsequently identified, 1s much rarer than chronic toxicity. The latter only becomes evident after long exposures, and is almost never related to the causative agent. Natural Compounds in Food An example of compounds which occur naturally in food and cause chronic toxicity are the goitrogens. It was not until 1928 that the relation between diet and goitre had been established, but it was 1949 before a goitrogen was isolated from Brassicae, an important family of food plants including such vegetables as cabbage, kale and turnips. The compound isolated was 1-5-vinyl-2-thiooxazolidone, which owes its activity to its ability to stimulate the secretion thyrotrophin by the pituitary gland. 1-5-vinyl-2-thiooxazolidone does not occur free in Brassica seeds but is produced probably from OH | NaOS(0),0-C(SC,H,,0;) = NCH,CHCHCH= CH by enzymatic hydrolysis. Because the compound contained sulphur, investigations have been * Presidential Address delivered before the Royal Society of New South Wales on Ist April, 1970. carried out into the effect of sulphate concentra- tion in the soil on the production of this goitrogen. It was found that high sulphate greatly increased goitrogen production. This compound is not the only goitrogen found in the cabbage family: Langer e al. (1962) suggested that the thiocyanate content of cabbage would contribute to its goitrogenicitv. However, a daily intake of about 22 lb. of kale or cauliflower would be required to furnish enough thiocyanate to produce a goitrogenic concentration in the blood. Fortunately, much of the activity of these compounds is destroyed by cooking. Among other substances in food which have some goitrogenic activity attributed to them are non-iodine halides, calcium, arsenic, cobalt, ergothionine, cyanoglycosides and polysulphides. In the case of the non-iodine halides the evidence is slight. In some areas, notably in England, Punjab, South Africa and Soviet Asia, where fluoride occurs naturally in water, the presence of endemic goitre seems to be co-extensive with the fluoride. However, in similar circumstances in Israel, where the iodine intake is adequate, the incidence of goitre is low. Chemicals with estrogenic activity occur in some foods. Two substances of this type have been identified in soya beans: these are 4’.5,7-trihydroxyisoflavone (genestein) and 4’,7- dihydroxyisoflavone (daidzein). These com- pounds are weak estrogens. Many plants have shown some estrogenic activity ; some of these are carrots, wheat, rice, oats, barley, apples, cherries, plums, and parsley. Because the estrogenic activity of plants is very weak, it is almost impossible to consume sufficient material to invoke an estrogenic response. Of the toxic chemicals found in food, the cyanogenetic glycosides are one of the most dangerous groups. These compounds, widely distributed in the plant kingdom, yield, on hydrolysis, hydrocyanic acid. Amygdalin, which occurs in the seeds of bitter almond, is perhaps the best known of the cyanogenetic 164 glycosides. This compound, on hydrolysis, yields hydrocyanic acid, gentiobiose and benzaldehyde. The Lima bean, a legume used extensively for food, contains a cyanogenetic glycoside, phaseolunatin, which on hydrolysis yields glucose, acetone and hydrocyanic acid (HCN). It appears that the hydrolysis takes place only if the beans are crushed before cooking. Viehoever (1940) found that the HCN liberated from crushed beans varied from 0:01 0:3%. Serious outbreaks of poisoning from cooked Lima beans have been reported from various parts of the world (Rathenasinkam, 1947 ; Dunbar, 1920). Experiments with cooked Lima beans raises the possibility that the human body may contain enzymes capable of releasing significant quantities of HCN from cyanogenetic glycosides (the lethal dose of HCN is about 100 mg.). The occurrence of alkaloids in the plant kingdom is fairly common, and well over 4,000 different alkaloids are known. The humble potato contains an alkaloid, solanine, mainly in the tissue immediately below the skin. The concentration is very high in the green tissue developed prior to shooting. Tea and coffee contain the alkaloid caffeine, and infusions of these plants may contain several per cent. of this alkaloid. The stimulating effect of tea and coffee is due to caffeine, which is said to facilitate mental and muscular effort and to diminish drowsiness ; caffeine also has a marked diuretic effect. A large number of amino compounds, many with high physiological activity, occur naturally in food. Included amongst these are the highly potent amines histamine, tyramine, tryptamine, and 5-hydroxytryptamine (serotonin). Bananas, plantains (sugar bananas), pawpaw and pineapple contain serotonin in concentrations up to 10 mg. per 100 g. of fresh fruit. Even the tomato contains about 0-4 mg. serotonin per 100 g. Aged cheese is a source of physiological amines, e.g. one specimen of Camembert contained 200mg. tyramine per 100g. The primary route of detoxification of primary amines is the oxidation to the corresponding carboxylic acid through the agency of the enzyme monoamine oxidase. As might be expected, accidents have been reported when patients were treated with monoamine oxidase- inhibiting drugs. One such accident occurred when a group of patients, receiving the tranquil- lizer “‘ Parnate”’ (tranylcyramine), ate some matured cheese. This gave rise to hypertensive crises which were fatal in some cases. The J. W. G. NEUHAUS serotonin intake of certain African peoples who use plantains as a major item of diet may reach 200 mg. per day. The high incidence of cardio- vascular disease amongst these peoples may be related to the high intake of serotonin. One of the most important groups of anti- enzymes contained in food is the cholinesterase inhibitors. The cholinesterases occupy a unique position in the animal kingdom, for they are involved in nerve impulse conduction and thus are vital to the well-being of animals. Some edible plants which yield cholinesterase inhibitors are, for example, broccoli, cabbage, pepper, Valencia orange, pumpkin, squash, carrot, strawberry, apple and potatoes. In the case of the potato it appears that the alkaloid solanine may be the cholinesterase inhibitor. There are many other substances in food which have toxic effects; for example, there is a complicated antagonism between unsaturated fatty acids and carotene. The foregoing examples should serve to illustrate that food is not necessarily safe. Natural Additives in Food FUNGI Bacterial or fungal infections can give rise to toxin in food. For example, Clostridium welshi, a spore-forming anaerobic organism, is often the causative organism in food poisoning. A common source of poisoning is chicken salad which has been stored at room temperature for some time before serving. Among the compounds which are formed in food by micro- organisms are a group of substances which can cause fibrous growths. Some of the most important of these compounds are the aflatoxins. The effect of these substances was first noticed in England when about 100,000 turkey poults died in 1960 from what was then known as “turkey X disease ’’. The disease was soon traced to peanut meal. Subsequently, in 1961, it was found that the infection was caused by a strain of Aspergillus flavus, and the toxic substance was named “ aflatoxin ”’. The aflatoxins cause serious liver toxic reactions, producing fibrosis and cirrhosis in young Rhesus monkeys. These compounds cause a_ high incidence of carcinomas in the livers of rats at levels of 1-6ug. per day. The purified afla- toxins are carcinogenic in the livers of rainbow trout at a level of about 0-08 p.p.m. METALS Practically every element in the periodic table can occur either naturally or accidentally CHEMICALS IN FOOD in food. Some metals, like iron and cobalt, are essential for the well-being of animals. Some, such as arsenic and barium, have no known useful function in the diet and are harmful at quite low concentrations. No method is known to avoid metallic contamination of food if the metal occurs in the soil where the crops are grown or where the animals graze. The traces concerned are usually so small that no harmful effects arise from their consumption and it is possible that harmful effects may arise in their absence. Of the trace metals essential for life, copper is an interesting example. Formerly, much of the food processing equipment was fabricated from copper; today stainless steel is the principal metal used. Some years ago there was a spate of complaints of “ off ”’ odours and flavours in bottled milk delivered to homes. This problem was traced to the copper content of the milk. Copper, which normally occurs in milk at about 0-15-0-2 part per million, had increased to several parts per million. Investigation revealed that the excess copper was coming from pasteurizers in the milk factory. This milk, on standing in sunlight, very rapidly developed “ off’ flavours and odours due to the copper greatly accelerating the normal staling processes in the milk fat. These effects are usually masked by bactrio- logical changes producing, amongst other things, lactic acid. Copper is essential for animals because it is involved in haemoglobin formation. Many plants and animals used for food contain traces of copper such that the daily intake is about 2mg. This is more than sufficient for metobical requirements. Lead is one of the harmful metals which occurs in traces in practically all foods. These traces are derived from the soil in which the plant grows. Research indicates that some lead may be derived from lead tetraethyl used in motor spirit. As early as 1930, fears were being expressed about the effects of leaded petrol, and the government laboratory of the Depart- mental Committee on “ Ethyl Petrol” found that the average amount of lead inhaled from the air of towns in Great Britain was 0-077 mg. per day. Lead is also a frequent accidental contaminant of food, sometimes from unsus- pected sources such as old paint on ceilings slowly chalking or from leadlighted panels in kitchen cabinets. Substances Deliberately Added to Food These substances are often referred to as food chemicals, and are often very much safer than chemicals naturally present. Chemicel 165 compounds are added to food to achieve one or more of the following aims: to improve the keeping quality, the nutritional properties and the appearance or to improve tastes, and thus consumer acceptability of the food. The sub- stances used fall into three main categories : (a) Complex chemical substances such as proteins extracted from other foods, e.g. casein added in sausages. (6) Naturally-occurring simple substances such as salt, acetic acid and ascorbic acid. (c) Synthesized substances not found in nature, such as antioxidants, emulsifiers, preservatives and colours. At the Delaney enquiry in 1954 it was stated that there were 704 different chemicals being used in food in the U.S.A. Now the number of chemicals given approval for such use by the Food and Drug Administration of the U.S.A. is about 10,000. Such is American law now, that any new substance proposed as a food additive must not only be safe, but must be proved to be safe, usually by protracted animal feeding experiments. The testing programme of food additives has resulted in some substances being removed from the permitted list on evidence which is so slender that it is almost impossible to find the reason. Fortunately, sodium chloride is one of the substances on the “gras ”’ (generally regarded as safe) list, for if it were to be tested under the conditions required, it would fail miserably and be banned in the Wes) Preservatives have been in use from very early times. The process of “salting” or ‘ smoking ”’ fish was perhaps the first preserving process using chemicals. ‘“‘ Smoking ’’, a once popular process, added formaldehyde amongst other things to the meat. Modern preservatives include disodium acetate, which is used to preserve bread (anti-mould), where up to 6 oz. is used per 100 Ib. of flour. Benzoic acid, which occurs naturally in cranberries, is used exten- sively in soft drinks. Benzoic acid has been used in ice to keep fish fresh. It prevents trimethylamine being detected without inter- fering with bacterial spoilage. This highlights one of the hazards of using chemical pre- servatives. It is most important that the preservative does not permit the growth of abnormal flora such as pathogens while obscuring spoilage changes. Other acid preservatives include sorbic acid used to prevent mould growth in baked goods. Sulphur dioxide has been used for a long time as a preservative, especially in beverages, dried 166 fruits and meats. The action of sulphur dioxide is not clearly understood, but it may inhibit sulphur-containing enzymes. Sulphur dioxide also acts as an anti-oxidant, for it can be used to protect ascorbic acid during the drying of fruit. Unfortunately, sulphur dioxide destroys thiamine in the food treated with it. Mapson et al. (1961) reported a 30°, destruction of thiamine in sulphite-treated chipped potatoes, and Mallette e¢ al. (1946) reported almost complete destruction of the thiamine in cabbage blanched in sulphite solutions, while riboflavin and niacin were unaffected. Another pre- servative is hydrogen peroxide, which is used to prevent staling of cream. The advantage of this preservative is that the by-products are oxygen and water. Further, excess peroxide can be destroyed by catalase, which can eb inactivated by heat and therefore does not affect further processing. Fatty foods are susceptible to oxidative changes in the fat molecule with the production of rancid flavours and odours. The autoxidation of fats involves the formation of a free radicle. This process can be catalysed by traces of metals such as copper, 0:05 p.p.m. of which was found to double the rate of oxidation. Once a free radicle is formed, the reaction becomes self- perpetuating, with the regeneration of the free radicle and the production of a_ peroxide molecule : K-40, =RO: (peroxy radicle) RO2:+RH=ROOH (peroxide) +R’. To slow the rate of autoxidation, compounds like butylated hydroxy anisole and_ propyl, octyl or dodecyl gallate are used. These compounds can exchange the free radicle with the fat molecule, but because of steric hindrance the free (radicle so produced 1s, unable: te propagate further free radicle formation. The chain is then terminated by dimerization : | R:'+AH (anti-oxidant) =RH-+A° A‘+A° =a or A'+R° AK (imactive): It is obvious that these processes the anti-oxidant. ce +) use up Compounds like glycerolmonostearate and sorbitan or polyoxyethylene fatty esters are used as emulsifying agents. These compounds improve volume and uniformity of flour con- fectionery. In bread they help to produce a loaf with a softer crumb and somewhat slower staling rate. The texture of ice-cream and other frozen desserts is dependent, in part, on the size of the JW GS NEUHAUS ice crystals in the product. The size of ice crystals can be controlled to some extent by the addition of some form of stabilizer. Substances typically used include agar-agar, gelatin, gums and alginates. A group of chemical compounds commonly used in food are the dyes, the “Coal Tar Colours ’’, so called in an allusion to the early methods of production. There are about 46 separate dyes produced specifically for use in food. Of this number only six are common to 40 or more countries—-three reds, two yellows and one unsatisfactory blue. It is almost certain that the permitted lists of each country have been drawn up with the same object in mind ; that is, to protect the ultimate consumer. Unfortunately, a satisfactory list of universally acceptable colours does not exist. The New South Wales list has 23 shades: eight reds, one orange, six yellows, one green, two blues, one violet, three browns, and one black. Some of these dyes contain an azo group and are, according to one school of thought, suspect. The most studied azo dye is 4-dimethylamino- azobenzene, known as butter yellow or methyl yellow. This dye was formerly used extensively in some countries as a food colour. The dye has been shown to be carcinogenic to rats, but strangely enough only when the diet was nutritionally deficient, particularly in riboflavin, which participates in the metabolism to harmless derivatives. There is no firm evidence that any of the food colours have caused any adverse reactions in man. The chemicals in food which have received the greatest publicity are the residues of pesticides used to control weeds, insects, fungi or plant growth. The use of large quantities of pesticide is usually justified by the need to produce more food. Of the pesticides, D.D.T. has received most attention. Many publica- tions have appeared pointing out the dangers of the accumulation of chlorinated pesticide residues. Some have pointed to the decrease in fertility of some species of sea birds, others have drawn attention to the presence of D.D.T. in the fat of the Weddle seal. With all the spate of literature it is almost impossible to tell whether the reduction in fertility of some sea birds is due to D.D.T. or to some other as yet unidentified cause, or if, indeed, a reduction in fertility has occurred at all. The danger is that chlorinated pesticides may be blamed and the true cause ignored, especially when efforts are being made by some pressure groups to have D.D.T. banned. CHEMICALS IN FOOD The residue position is so emotionally charged that it will be very many years before a truly objective perspective can be obtained; until this time the true position will remain obscure. The problem with chlorinated pesticides appears to be related to their very long life and the fact that they are fat-soluble. Endrin and dieldrin, in relatively large doses, such as arise from accidental ingestion of toxic quantities, produce epileptic-type spasms and are feared for this reason. The organic phosphorous insecticides are, generally speaking, much more toxic than the chlorinated compounds because they are cholin- esterase inhibitors. The life of these phosphorous compounds is very much shorter, being measured in weeks or days rather than years, which is the rule for the chlorinated compounds. Because of their short life, they present relatively little problems of chronic toxicity. Nevertheless, a major hazard can develop from the use of these compounds. The recommended usage includes a withholding time after application, but the withholding time is almost impossible to police, partly because market and weather conditions may dictate an earlier harvest than was anticipated. Pesticides are not the only chemicals used in agriculture which cause concern. Some German work has indicated that the humble spinach Department of Health, Division of Analytical Laboratories, Lidcombe, N.S.W. 167 can be deadly to babies when grown in soils with a high available nitrogen content. The nitrate content of many leaf vegetables is dependent on the available nitrogen in the soil. After harvest and cooking, some of the nitrate may be converted to nitrite. Nitrite is a dangerous substance because it causes slowly reversible changes in the haemoglobin of the blood, thus reducing the oxygen capacity of the blood, which may result in cyanosis and death in severe cases. With all the problems associated with food, we must eat to live and must consume about 400 g. of food each day. Naturally, each one of us can no longer produce all his own food, and must depend more and more on processed food. Perhaps in time all food will be safe to eat. This I know: the testing of new additives is so rigorous that the danger from this source is much Jess than that from “ natural ” food. References DunBar, W. P., 1920. Gesundh. Ingr., 43, 97. LANGER, P., SEDLAK, J., AND MicHaAjLovskij, N., 1962. Bratisl. Likarske Listy, 42, 393. MALLETTE, M. F., Dawson, C. R., NELson, W. L., AND GoORTNER, W. A., 1961. Ind. Eng. Chem., 38, 437. Mapson, L. W., AND WaGeEr, H. G., 1962. Food and Agri., 12, 43. RATHENASENKAM, E., 1947. (India), 91, 59. 2OSct; J. Proc. Insti. Chemists Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 169-171, 1969 The Occurrence and Significance of Triassic Coal in the Volcanic Necks near Sydney L. H. HAMILTon School of Applied Geology, University of New South Wales R. HEtBY New South Wales Department of Mines, Sydney AND G. H. TAyYLor C.SL.R.O. Division of Mineral Chemistry, Chatswood, N.S.W., 2067 ABSTRACT—The breccia pipes near Sydney contain numerous inclusions of coal. Spores have been macerated from some of this material, the microflora obtained being no older than Hawkesbury Sandstone equivalent. The coal both in the breccia pipes and in the peripheral contorted zones is of bituminous rank, which is evidence that it has not been heated above quite modest temperatures. Introduction Although David (1896) suggested that the coal in the Euroka Farm breccia pipe was probably derived from the ‘“‘ Hawkesbury Sandstone ’’, coal fragments in other similar breccia pipes near Sydney have generally been assumed to be of Permian age. New evidence indicates that coal in at least several of these breccia pipes is of Triassic age and is now at a lower position than the strata from which it was derived. The volcanic necks under discussion are situated in an area extending to about 25 miles north, 43 miles east, and 30 miles south-east of Sydney. Localities are given in the table as Army Grid references for the Sydney Four-Mile Topographic Sheet. Further details on the localities are given by Adamson (1966). Wilshire (1961) has described some of the volcanic necks as layered diatremes. They generally occur as vertical pipes with circular to irregular elongated outcrops ranging in area from a few acres to more than 40 acres. The breccias consist predominantly of altered basaltic fragments, commonly amygdaloidal, set in a matrix of clay and carbonate minerals and scattered quartz grains. They also contain a wide variety of other igneous and sedimentary rock fragments, including coal. Peripheral Zones in the Pipes At some localities contorted beds of sedi- mentary rocks have been exposed between the breccia and the non-deformed country rocks. Coal occurs sporadically in such _ peripheral zones at Minchinbury quarry and Erskine Park quarry. At an exposure in Minchinbury quarry the contact between the contorted sediments and the wall rock is marked by a small] fault. Here the contorted sediments are less deformed and are clearly part of the country rock. The sedimentary beds in the peripheral zones are generally centroclinal. The coal in the peripheral zones attains a maximum thickness of about one foot. It is a moderately bright humic coal and contains a high proportion of exinite, especially in the form of leaf cuticle. This abundance of leaf cuticle is not typical of the Permian coals of the Sydney basin, but is much more characteristic of some Triassic coals—such as the Ipswich coals of south-eastern Queensland (Cook and Taylor, 1963). The maximum reflectance of the vitrinite in the contorted sediments lies within the range 0-87-0:97%. These low reflectance figures suggest maximum temper- atures probably of less than 100° C. Deformation in the contorted sediments has resulted in fragmentation of the coal, with rotation of the fragments and their subsequent bonding by “pressure welding’”’. The optical anisotropy of these fragments, however, is related to the original direction of bedding, indicating that the fragments were not plastic during deforma- tion. This also indicates that the coal was subject to a maximum temperature well below 350° C., at which the vitrinite would become appreciably plastic (Brown, Taylor and Waters, 170 1965). It also suggests that this coal may have been of sub-bituminous or bituminous rank at the time of deformation. An abundant, well-preserved, microflora has been extracted from the coal in the contorted sediments. It consists of Alisporites spp., Avatrisporites spp., Cadargasporites senectus, Converrucosisporites camerom, Dictyophyllidites mortont, Cycadopites. mtidus, Kraeuselisporttes differens, Lycopodiumsporites sp., Mucroreticu- latisporites sp., Neoratstrickia taylor, Nevesi- sporites limatulus, Polypodusporites 1psviciensis, Punctatisporites spp., Punctatosporites walkom and Verrucostsporites spp. In particular, the presence of Cadargasporites senectus in association LE. i. HAMILTON Ei TAL. The coalified wood fragments are generally elongated and range in length from about one millimetre to some tens of centimetres. They — are commonly surrounded by rims up to several millimetres thick of calcite containing euhedral prismatic crystals of quartz. The presence of the rims suggests that the fragments of woody coal have shrunk, usually to between one-half and three-quarters of their former volume. Also, the even thickness of the rims around fragments of banded coal suggests that they have shrunk uniformly to some 80-90% of their former volume. A well-preserved microflora has been extracted from two coal specimens from the Hornsby Localities of Pipes and Reflectances of Coal Specimens Pipe Hornsby Quarry Minchinbury Quarry Erskine Park Quarry Richardson’s Farm .. Norton’s Basin Fragments | Davidson’s Quarry in Bulls Hill Breccias Patonga ee - a Fitzpatrick’s First Quarry Gilliigans Road . an Campbelltown Bloodwood Road Peripheral | Minchinbury Quarry Zones Erskine Park Quarry Locality Maximum Reflectance Adamson’s of Vitrinite Army Grid (1966) at A of Reference Reference 527 nm: 409,837 4 0:98-1:26 383,824 5 0:84-0:92 379,822 6 0:85-1:09 382,821 ol 0:80-0:86 361,817 35 0:76-1:04 383,835 7 0:81-0:96 389,818 32 0:92-0:97 428,859 —— 0-73—1-78* 391,824 28 0:93-0:98 405,840 0 | 0:66-0:91 377,786 36 1-80-1- 90} 407,852 14 0:78-0:94 383,824 5 0:76-0:96 379,822 ol 0:82-1:04 * The material of higher reflectance shows textural evidence of heat alteration, presumably by the basaltic intrusion which occurs in the pipe. + A single specimen from vicinity of intrusion which appears to have caused abnormal reflectance. with Kvraeuselisporites differens and WNevest- sporites limatulus indicates that the microflora is no older than the equivalent of the Minchinbury Sandstone, i.e., it is of M.—U. Triassic age. Coal Fragments in the Breccias Every breccia pipe in the Sydney region so far examined by the writers contains sparsely and unevenly distributed coal fragments. Although the coal fragments in the breccias are now of approximately the same rank as the coal in the peripheral zone (i.e., high volatile bituminous), most of these fragments appear to represent former single pieces of wood. breccia. It consists of Alisporites spp., Avairi- sporites spp., Cycadopites mitidus, Duplexi- sporites gyratus, Granulatisporites minor, Kraeuselisporites pallidus, Neoratstrickia taylort, Osmundacidites spp., Putlasporites plurigenus, Polypodtisporites ipsviciensis, Punctatisporites spp., Punctatosporites walkomt, Verrucosi- sporites sp., and Vutreisporites pallidus. The microflora is dominated by Kraeuselisporites pallidus and Pilaspovites plurigenus and repre- sents a particularly specialized assemblage reminiscent of some of the microfloras extracted from Ipswich coals of Triassic age. The presence of Duplexisporites gyratus indicates that the microflora is certainly no older than middle Hawkesbury Sandstone equivalent. OCCURRENCE AND SIGNIFICANCE A well-preserved microflora also has been extracted from coal in the Patonga breccia. It consists of Acenthotriletes sp., Alisporites spp., Cycadopites nitidus, Cycadopites sp., Ductyo- phyllidites mortont, Kraeuselisporites differens, Monosulcites sp., Neoratstrickia taylort, Osmunda- cidites spp., Pilasporites plurigenus, Polypodti- sporites tpsviciensis, Punctatisporites spp., Vitret- sporites sp., and Cuirculisporites parvus. The microflora is dominated by Alisporites spp. and Neoraistrickia taylort. The acritarch Czrrcul- sporites parvus is also particularly common. Overall, the assemblage is similar to the microfloras described previously, the presence of Cycadopites nitidus indicating that it is no older than Hawkesbury Sandstone equivalent. The coal fragments from which spores have been extracted are petrologically very similar to the coal in the peripheral contorted zones at the margins of the Erskine Park and Minchinbury pipes. A comparison of coaly material from the various breccia pipes and the peripheral zones is given in the table. The reflectances of woody and banded coals fall within the same range, although woody coal is in general isotropic and banded coal is anisotropic. The table shows that the maximum reflectances of vitrinite from coal in the peripheral zones mostly lie within the same range as those from the breccias. All of the values are significantly lower than those for Permian coal in the northern part of the Southern Coalfield, N.S.W., where the maximum reflectance values so far recorded lie between ino, and. 1-51%. Discussion The rank of the coaly material at the time of its incorporation in the breccia poses some- thing ofa problem. The properties of fragments of banded coal in the contorted sediments and, probably, in the breccia also, point to the coal having been at or close to the bituminous coal stage of rank. However, this would appear to conflict with available stratigraphic evidence, which suggests that an insufficient thickness of sediments could have overlain a Wianamatta- age coal at the time the breccia was formed. OF TRIASSIC COAL NEAK SYDNEY i All microfloras recovered from the coal to date indicate a specific Triassic age for the breccia formation. This is consistent with the observation that volcanic detritus is the dominant component of Wianamatta Group sediments above the Ashfield Shale, suggesting contemporaneous volcanic activity. There is also some evidence that at least one of the volcanoes (Richardson’s Farm) has been buried by Wianamatta sediments. None of the coal shows evidence of profound thermal alteration, which, had it occurred, would have been indicated under the microscope by changes in the optical and_ structural properties of the vitrinite and exinite minerals. In the same way spores are excellently preserved after maceration. The banded coal fragments have undergone very little deformation while in the breccia, and the only effects attributable to their incorporation are shrinkage, as indicated by rims, and a possible slight increase in rank. Some of the woody fragments of coal in the breccia have deformed plastically, apparently prior to a fairly uniform shrinkage. These effects of shrinkage and rank are probably the result of slight increases in temperature. The low temperature indicated is consistent with the hypothesis that cooling may have occurred as a result of adiabatic expansion. This is also suggested by the glassy nature of the basaltic fragments (though much of this is now altered) and by the occurrence of tiny vesicles in the same material. References ApAmson, C. L., 1966. The Crushed Stone and Gravel Industry in the County of Cumberland, N.S.W. Contracting and Construction Equipment, October. Brown, H. R., TAytor, G. H., and Waters, P. L., 1965. Research into the Production of Metal- lurgical Coke from Australian Bituminous Coals. Proc. Eighth Commonwealth Min. Metall. Congr., 6 (General), 911. Cook, A. C., and Taytor, G. H., 1963. The Petro- graphy of Some Triassic Ipswich Coals. Proc. Aust. I.M.M., No. 205, 35-55. Davip, T. W. E., 1896. Anniversary Address. /. Proc. Roy. Soc. N.S.W., 30 (postscript on p. 69). WILSHIRE, H. G., 1961. Layered Diatremes near Sydney, New South Wales. J. Geol., 69, 473-483. Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 173-187, 1969 The Coolac-Goobarragandra Ultramafic Belt, N.S.W. H. G. GOLDING The University of New South Wales AxsstTRACT—The Coolac-Goobarragandra ultramafic belt, in the south-east of New South Wales, delineates a steeply inclined sheet of peridotite and serpentinite 56 km. long and up to 2km. thick, which occupies a tectonic zone between western Lower Palaeozoic beds and the Siluro-Devonian Burrinjuck granite mass on the east. Petrogenetically critical components of the principal rock association of the belt include predominant cataclastic harzburgite which encloses autolithic Cr-rich and Al-rich chromitite pods, and gabbro-derived garnet-vesuvianite rodingite veins and rootless dykes which penetrate both the harzburgite and the chromitites. A magmatic gabbro-wehrlite complex of doubtful status occurs in the north. The whole association is tentatively interpreted as a mush- and tectonically-re-emplaced and partly re-intruded abyssal complex in which a quasi-stratiform configuration of harzburgitic mush and basic magma components at depth was to some extent reproduced but also telescoped at a shallow crustal level. 1. Introduction Ultramafic rocks in south-eastern New South Wales were referred to briefly by Carne (1892), Card (1896), Jaquet (1896), Raggatt (1925, 1936), Benson (1926), Brown (1929), David (1950), Adamson (1957), Joplin (1962) and Golding (1961-1967). The rocks occur at intervals within a broad linear zone trending south-south-east from Girilambone, near Nyngan ; through Fifield, Arramagong and the Coolac-Gundagai district to Tumut Pond, near Kiandra (Rayner, 1961); over a distance exceeding 300 miles (Figures 1 and 2). The terms Gundagai Serpentine Belt (Rayner, 1961), Lachlan Serpentinite Belt (Fraser, 1967) and Girilambone-Kiandra Belt (Golding and Bayliss, 1968) have been proposed for the whole zone. The Coolac-Goobarragandra ultramafic belt is the largest of the exposed subsidiary units within the Girilambone-Kiandra Zone, and its size and accessibility recommend it as a type unit in studies of the whole zone. Field observations in the period 1961-1965, the examination of some 1,200 thin sections (including those of Veeraburus (1963) and Fraser (1967)) and unpublished studies of the chromitites (Golding, 1966) have contributed to the writer’s conception of the belt. This paper summarizes the available data on the setting and petrography of the belt, draws attention to problematic features requiring B QUEENSLAND _.- nes, mn Sy aes a eee GIRILAMBONE A ‘,COOLAC BELT ~~ g ~~ "\ KIANDRA \ VICTORIA * 0 100 200 We KM ee MILES FIGURE 1.—Sketch map of eastern New South Wales showing the principal ultramafic belts. (A) The Girilambone-Kiandra Belt enclosing the Coolac sub- sidiary Belt. (B) The Great Serpentine Belt of New South Wales. (C) The Baryulgil Belt. 174 e ‘ GIRILAMBONE 148 MIANDETTA “4 oO NYNGAN ’ o HONEYBUGLE Oo TOTTENHAM O FIFIELO ARRAMAGONG '1O THUDDUNGRA , BERTHONG , O WALLENOBEEN Ub) CULLINGA lol cooLac GUNDAGAI& | TUMUT O GOOBARRA- GANDRA 0 20 40 MILES O KIANDRA FIGURE 2.—Reported occurrences of ultramafic rocks in the Girilambone-Kiandra Belt. more intensive study, and outlines a sequence of events to account for aspects of the observed rock association. In the following account the terms Coolac belt or belt refer to the Coolac-Goobarragandra subsidiary unit, which is more closely defined hereunder. H. G. GOLDING 2. Location and Physiography The Coolac belt includes two steeply dipping, almost contiguous ultramafic lenses of unknown depth which are separated by a few hundred yards and which, end to end, outcrop almost continuously for 35 miles (56km.) along the strike. The principal or northern lens is 27 miles long and attains a maximum thickness. and outcropping width of about 2,200 yards (2km.). The southern lens is composite and includes at least two narrow, sub-parallel serpentinite sheets separated by low-grade metamorphic rocks having a maximum overall width of about 600 yards. The belt trends south-south-east from the Hume Highway, five miles north-east of Coolac and 240 miles by road west of Sydney ; crosses the Murrumbidgee River at Gobarralong ; passes some eight miles east of Tumut; and terminates one mile south of the Goobarragandra River, on Patten’s Ridge (Figure 3). Outcrops. of ultramafic rock beyond these limits (Golding, 1966 ; Boots, 1968) are not considered here- under. The region traversed by the belt is broadly divisible into three meridional physiographic zones which reflect lithologic and_ structural discontinuities. The eastern zone _ consists. largely of a dissected plateau about 3,000 feet A.S.L. and is underlain by the Burrinjuck granite mass. The central physiographic zone is also a zone of major tectonism which encloses all the ultramafic rocks with the possible exception of certain wehrlites in the extreme north. This zone largely coincides with the ridges and scarps of the Mooney Mooney and Honeysuckle Ranges indicated, with subdivisions, in Figure 3. The western zone descends to 800 feet A.S.L. at the Tumut River west of the ultramafic belt, and is underlain by Lower Palaeozoic, probably Silurian, sedimentary, volcanic and low-grade metamorphic rocks, folded about sub-meridional axes, locally intruded by porphyrites and, in the south, by the Bogong granite of probable Devonian age (Adamson, 1957; Veeraburus, 1963 ; Golding, 1966; Fraser, 1967; Boots, 1968). 3. Broad Lithologies and Structure In the Honeysuckle Range both serpentiniza- tion and shearing increase westward so as to roughly demarcate an eastern sector pre- dominantly of blocky, partly serpentinized hazrburgitic peridotite from a western sector of sheared serpentinite. This east-to-west division persists into the southern half of the Mooney THE COOLAC-GOOBARRAGANDRA ULTRAMAFIC BELT, N.S.W. Mooney Range, but further north gabbroic rocks take the place of serpentinite on the west and are associated with wehrlite and harz- burgite (Figure 4) in the North Mooney complex. The narrow southern lens is lithologically similar to the western sector of the Honeysuckle Range. The ultramafic rocks are separated from the western beds by a marginal zone 10 to 100 yards wide of pseudo-concordancy, within which fault septa of serpentinite and western beds alternate. Cleavage in the western beds, lithologic- structural planes in the marginal zone, fractures in the serpentinite, major joints in the harz- burgite and foliation in the eastern granite all trend with the strike of the belt and are sub- vertical. Faulted contacts of serpentinite with eastern granite and with western beds, along Bombowlee Creek Road and Tumorrama Road respectively, dip east at 65° to 80°. The eastern flanking rocks consist partly of granodiorite and the terms granite and granitic are therefore used broadly hereunder. Granitic rocks are massive and leucocratic at North Mooney Ridge and Mt. Lightning, strongly foliated and biotite-rich along Mundongo Scarp, and variably foliated elsewhere. The intensity of the foliation decreases away from the contact. Granitic rocks of the same mass 10 and 20 miles east of the belt were respectively dated as Siluro- Devonian and Middle to Upper Devonian by Evernden and Richards (1962). Alkali olivine basalts, dolerites and limburgites of probable Tertiary age cap the granite at the eastern contact of the harzburgite on the Red Hill Plateau (Veeraburus, 1963). At Patten’s Ridge a wedge of amphibole schists, epidosites and amphibolite separates the serpentinite from the eastern granite. 4, The Eastern Contact The eastern contact is marked by a zone of brecciated granite up to several yards wide abutting peridotite in the Honeysuckle Range ; and by a selvage of laminated granite mylonite, some inches wide, abutting sheared serpentinite along Mundongo Scarp. Apophyses and thermal effects indicating liquid magmatic intrusion of either rock into the other; schlieren of either rock within the other ; and fragments of ultra- mafic rock in the marginal granite breccia are all absent. Large enclosures of the eastern granite in marginal harzburgite, however, occur on both banks of the Murrumbidgee River and are either wedges stoped from the granite by ascending harzburgitic material, or locally infaulted slices. These features establish the overall tectonic character of the eastern contact 175 but suggest that marginal granite brecciation pre-dated the existence of the harzburgite at the observed contact. Although slices of peridotite, away from the contact, are flanked by selvages of sheared serpentinite between which they may have ascended tectonically, much peridotite and serpentinite at the contact itself is massive and lacks slickensides and megascopic brecciation. Thin sections, however, reveal post-serpentine microbrecciation which is superimposed on the normal pre-serpentine microcataclasis (Section 6). These features are compatible with the intro- duction of the harzburgite as a crystal mush into a pre-existing fracture and the subsequent ascent, minimal at the eastern contact but increasing westward, of slices of solid harzburgite. Post-tectonic fluids localized by the fault promoted the formation of magnesite, chlorite, opal and chalcedony in marginal peridotite from place to place; and induced sporadic metasomatism of the granite breccia to resistant prehnite- and zoisite-rich rocks which stand in relief along the contact, 5. The Western Marginal Zone From north to south in the Mooney Mooney Range ultramafic rocks are successively flanked on the west by gabbros; by intertonguing, serpentinite and basic volcanics: and by alternating septa of volcanics, rodingite, albitite, cherts and serpentinites. At Mt. Lightning some marginal basic volcanics enclose angular fragments of serpentinite; others consist of unaltered spilitic variolite (Golding, 1966). Shales abut serpentinite in the Adjungbilly Valley and separate prominent sheets of sheared serpentinite along the Tumorroma Road. Andesitic rocks intertongue with serpentinite along Keef’s Scarp and persist to the southern extremity of the belt. The development of the western marginal zone presumably involved (i) the ascent of harzburgitic mush into wet sediments and volcanics ; (ii) the concomitant coherence and serpentinization of the mush; and (iii) the piecemeal ascent of serpentinite, and perhaps of lenticles of country rock, by slip on fracture planes. The recurrence of such movements is possible, perhaps when compression coincided either with hydrothermal episodes or with ae and dehydration of serpentinite (Raleigh, 1967). The tectonic zone has been regarded as an overthrust (Browne, 1929) and as a possible strike-slip fault (Lambert and White, 1955 - 176 fh. G: GOLDING S. MOONEY MT. LIGHTNING AD jyy ober 1) Zz 2 ae (= Se © — | | | | | | a | | | | | | | | | | | | | | | | WELCH'S Ky RIDGE . we KANGAROO KANGAROO PLATEAU A MOUNTAIN RED all ELE PLATEAU ROAD ' N SS < MUNDONGO Ss“ u \ MUNDONGO TRIG. STATION te ; oe) N PATTENS VV \ RIDGE a\ 3000 — — MUNDONGO — — — — —TUMORRAMA -— FEET 2000; = FIGURE 3.—The Coolac-Goobarragandra ultramafic belt— physiographic features. Meridional section (left) and plan (right). THE COOLAC-GOOBARRAGANDRA ULTRAMAFIC BELT, N.S.W. GEOLOGICAL SKETCH MAP OF THE COOLAC GOOBARRAGANDRA ULTRAMAFIC BEE Basalt, limburgite and dolerite TERTIARY (7?) oS 5% Bogong granite AW Sheared' serpentinite = Harzburgite and massive serpentinite < EHEEE Wehrlite 4/,x/| Augite and hornblende A545) gabbros 7 = Intertonguing basic vol- a) canics and serpentinite EE Burrinjuck granite ae Sediments, volcanics and metamorphics SILURIAN (?) FIGURE 4. 177 178 Rod, 1966). Because it may delineate a major relict lateral crustal discontinuity, and a fracture which extended to the mantle (Ringwood, 1964), its evolution is regarded as the principal geologic problem of the belt. The contents of the zone present a more or less independent series of problems. 6. The Honeysuckle Range Harzburgite In terms of reconstructed (anhydrous) minerals, the harzburgite contains 60-95% (usually ~80%) of olivine, 2-40% (usually ~15%) of enstatite, up to 5% (usually ~1%) of diopside, and about 1% of chromite. Com- monly, about half the olivine and enstatite are serpentinized ; local transitions of harzburgite to bastite serpentinite are frequent; and occasional lenses of dunitic serpentinite devoid of pyroxene and bastite occur around chromite deposits and elsewhere in the eastern sector. In most outcrops the rock is massive, but a few reveal alternating enstatite-rich and dunitic layers, 1-2 cm. thick, traceable over a few feet. Megascopically, the harzburgite and derived serpentinite show orthopyroxenes, 5 mm. wide, within a groundmass which varies from medium grey and finely granular in rocks with densities of 3-0g.cm.3, which contain up to 6% of combined water; to black and aphanitic in rocks with densities of 2-7-2-4 g.cm.? which contain 9-11% of combined water (Table 1). Thin sections of harzburgite reveal rare clusters of olivine grains with allotriomorphic granular fabric and grains up to 2mm. wide showing deformation lamellae. Usually dis- oriented olivine sub-grains, 0-1 mm. wide, are cemented and replaced by unfractured bluish- grey serpentine enclosing sporadic magnetite granules. The olivine, about Fa,(2V,=—86-+3°) was fragmented before or during serpent- inization. The enstatite near Eng, (2V,—84-+-3°) encloses lamellae of clinopyroxene, and is ragged, warped and marginally replaced by recrystallized (?) olivine. The diopside and chromite grains are angular. The pervasive cataclasis of the harzburgite might be attributed to slumping or compressive deformation of a cumulate derived from mafic magma more or less at the observed site (Challis, 1965; Challis and Lauder, 1966). Other features of the Coolac rocks (Section 9), however, favour the ascent of the harzburgite in a largely crystalline condition from a substantially deeper level. H. G. GOLDING Apart from possible upthrusting of masses or slices of solid rock; proposed mechanisms for the emplacement of alpine-type peridotite which emphasize the role of solid components range from (1) emplacement of a crystallo- magmatic suspension (Smolin, 1964) ; and (2) of a stiff, semi-solid crystal mush rendered mobile by crushing, local melting and recrystallization, and capable (at times) of magmatic flow (Thayer, 1963a, 1964); to (3) emplacement of a near- solid crystal mush deforming plastically during the removal by filter-pressing of associated liquid (Raleigh, 1965); and (4) emplacement of a completely crystalline mass deforming at low to moderate temperatures by recrystal- lization and crushing (Ragan, 1963, 1967) ; or (5) deforming at higher temperatures by recrystallization alone (Green, 1964, 1967). The Honeysuckle Range harzburgite was probably emplaced in a heterogeneous manner involving several of these mechanisms which changed with increasing coherence of the mush during the emplacement period. The harzburgite presumably originated either as a gravity differentiate of a mafic magma or as a refractory residue formed by the partial fusion of pyrolite (Ringwood, 1964 ; Ringwood and Green, 1966) and the incomplete segregation of the fused and residual fractions. By either origin the material would have been largely crystalline, but associated with subordinate liquid, at its inception. The re-emplacement of this crystal mush within the tectonic zone during appropriate stresses to high crustal levels is visualized. Further aspects of the re-emplacement are suggested by the enclosures of other rocks within the harzburgite (Section 9). 7. The North Mooney Complex This complex occupies two to three square miles, mainly west of North Mooney Ridge, and is characterized by wehrlitic, gabbroic and harzburgitic rock types the mutual relations of which are obscure. The third type is probably an extension of the Honeysuckle Range harz- burgite, but apart from some inclusions within serpentinite (Section 10) more than 20 miles to the south the other types appear to be absent elsewhere in the belt. (a) The Wehrlites These rocks contain from 50% to more than 90% (and ~80%) of diopside and thus grade into clinopyroxenite. Orthopyroxene and feldspar are absent. Olivine, the second con- stituent, is usually represented by felted antigorite. Fine-grained (1mm.) and coarser THE COOLAC-GOOBARRAGANDRA ULTRAMAFIC BELT, N.S.W. (5-10 mm.) and massive and foliated types occur. The rocks are tougher than the harz- burgite. Fractured surfaces of pyroxene-rich types are greyish-green. Some wehrlite outcrops are separated by antigorite serpentinite presumably derived from dunite. This relation may _ represent (i) dykes of wehrlite in dunite or vice versa, (i1) associated tectonic slices of the two rocks, or (iii) wehrlite-dunite layering of settled, magmatic flowage or metamorphic types. Settled layering, however, is suggested by changes in the pyroxene-olivine ratio and in the grain-size of the pyroxene, in different specimens from the area; and by the micro- textures. Thin sections reveal colourless twinned diopside near Ca,,Mg,,Fe, (2V2,=5b°, N6=1-672), occasionally with marginal secondary amphibole. The crystals are variably fractured, but never granulated, and mush re-emplacement involving crushing is ruled out. The texture varies with the pyroxene-olivine ratio. Pyroxene-rich wehrlite reveals either allotriomorphic granular diopside with small interspaces containing antigorite, or shows frameworks of subhedral grains making point contacts. In pyroxene-poor wehrlite single diopside grains and small grain clusters appear to float in antigorite. Two varieties of basic pegmatite occur within the wehrlite. These are firstly segrega- tions a few feet thick of green clinopyroxene several centimetres wide, separated by cream- coloured saccharoidal zoisite, and _ secondly smaller patches of coarse hornblende associated with white saussurite which are localized along fissures near the junction with gabbros (Sub- section (c) below). (6) Marginal and Local Peridotite Variants Near the contact with granite in the extreme north the wehrlite contains a little garnet and turbid material, and occasionally veinlets of garnet, chlorite and serpentine replace olivine and diopside. Elsewhere in the mass rocks containing more antigorite than diopside, enstatite and antigorite, and enstatite and turbid material occur. Near the junction of wehrlite and harzburgite occasional veins of clinopyroxenite 1—2cm. wide penetrate harz- burgite. Rocks with distinctive magmatic textures also occur. In one variant green spinel separates clinopyroxene crystals enclosing resorbed olivine grains. In another, resorbed olivine is enclosed within ortho- and clino- pyroxene, which abut pale brown amphibole. 179 (c) Gabbrotc Rocks Of these rocks some contain variably uralitized augite, others additionally contain a brown- green hornblende, and a third group contains hornblende to the exclusion of augite and uralite. Other constituents include saussuritized plagioclase, chlorite, leucoxenized opaques, zoisite veinlets and, rarely, traces of garnet. The hornblende gabbros predominate in the north of the gabbro area (Figure 4), and possibly separate the wehrlite from the augite gabbros. Most outcrops of gabbroic rocks reveal uneven and coarse-grained apophyses intruding country rock volcanics. Such gabbros apparently crystallized in place from volatile magma, and some apophyses may represent country rocks remobilized by volatiles. In places hornblende gabbro (or diorite) intrudes volcanics which contain angular blocks and fragments of (?) similar gabbro (or diorite). The status of the North Mooney complex is problematic. Gabbro-wehrlite associations else- where occur in belts of serpentinized harzburgite (Taliaferro, 1943 ; Rynearson and Wells, 1944), in some stratiform and pseudostratiform com- plexes (Irvine and Smith, 1967; Rothstein, 1957 ; Smith, 1958), and in the Ural-Alaskan type of zoned complex (Ruckmick and Noble, 1959 ; Taylor and Noble, 1960 ; Taylor, 1967). Whether the wehrlite and gabbro are normal associates of the Honeysuckle Range harzburgite which have been largely removed by erosion, or whether the complex is fundamentally of a localized type, remains to be determined. 8. The Serpentinites X-ray and differential thermal analysis using the respective criteria of Whittaker and Zussman (1956) and Faust and Fahey (1962) indicate that the bastite serpentinites of the Honeysuckle Range consist predominantly of associated lizardite and chrysotile. Increasing westward serpentinization of this type within the harz- burgite is compatible with an influx of water into the peridotitic material from the western beds (Section 5). An increase in ferric at the expense of ferrous iron, and a decrease of lime accompanying increasing hydration of these rocks seems likely (Table 1). The _ bastite serpentinites are green or black, and the dunite serpentinites often brown or grey with purple haematitic streaks, suggesting the field term serpentine pseudobreccia. Thin sections reveal a mesh texture in most of these rocks, with brown turbid patches in the pseudobreccias. Sulphide and awaruite particles are conspicuous in some types (Golding, 1963, 1966). 180 Antigorite serpentinite predominates on North Mooney Ridge, and is accompanied by anti- gorite-talc and talc-magnesite rocks on Central Mooney Ridge. These rocks derived from dunite, harzburgite and pre-existing bastite serpentinite, the final modifications of which may have been promoted by one or other of the gabbroic TABLE 1] Chemical Analyses of Serpentinized Harzburgites and Serpentinites! 1 2 3 + 5 6 SiO, 41.79} 40.88} 40.24) 39.82) 39.92) 39.71 Al,O, 2.28) 1.30) 1.96) "1. 12) (0.04) ‘0.34 Fe,O, 1.40} 2.18) 4.80) 5.27) 7.53) 8.51 FeO 6.25) 5.77) 3.35) 2.80) 2.15) 0.84 MgO 39.52) 41.49) 36.88] 38.78) 38.52) 36.67 CaO 2.35) 1.51) 2.29) 0.54; 0.18) Nil Na,O 0:05) 0: 10) =="), 0204)" 0.03) 0-01 K,O 0.04, 0.06, —y, 0.02) 0.02) tr. H,O+ 5.45) 5.66] 8.75} 10.72) 10.84) 11.15 H,O— 0.03} 0.32} 0.23} 0.08} 0.04) 1.90 Co, 0.09) Nil 0.11) 0.22) 0.32) Nil TiO, 0.05) 0.02 — | 0.03) 0.03} 0.02 P.O; cr. 2: 0.02; 0.03} 0.02) tr. — — | Nil 0.13) 0.14 — Cr,O, 0.38) 0.35] 0.45) — — | 0.55 MnO: 0.11) -0.15)) %0292)"''0.11) 0.06) 0506 INI @) 74: 0.17; 0.25) 0.22) — — | 0.46 Li,O ; —- —| Nil 0.01} 0.01 — Free C 0.10) Nil Nil O507| 50512) sNal Totals* 100.06/100.04/100. 22} 99.73) 99.91]100. 22 9.G. 3.03} 3.00} 2.67) 2.45) 2.54) 2.34 * Corrected for loss 0=F,=0.06 in analyses 4 and 5. 1 Arranged in order of increasing water content from left to right. Samples 1-4 from the eastern, and samples 5 and 6 from the western sector. Sample 1: Grey, fine-grained, partly serpentinized harzburgite. Mt. Lightning. Grey fine-grained, partly serpentinized harzburgite. Mt. Lightning. Grey to black, fine-grained to aphanitic, massive bastite serpentinite containing about 25% of unaltered olivine and pyroxene. Adjungbilly Valley. Black, aphanitic, massive bastite ser- pentinite containing small amounts of unaltered olivine and pyroxene. Tumorroma Road. Sheared serpentinite containing traces of unaltered olivine and pyroxenes. Tumorroma Road. Massive, grey serpentine pseudobreccia with purple streaks, completely ser- pentinized and somewhat porous. Adjungbilly Creek. Analysis: Samples 1, 2 and 6: J. H. Pyle (N.S.W. Mines Dept.) ; Sample 3: R. Fisher (Sydney) ; Samples 4 and 5: A. Ithikasem (Thai Geol. Survey). Sources : Samples 1, 2and 6: Golding (1966) ; Samples 3, 4 and 5: Veeraburus (1963). Sample 2: Sample 3: Sample 4: Sample 5: Sample 6: H. G. GOLDING intrusions or late magmatic fluids associated with them. In the Bombowlee Creek-Mundongo area antigorite serpentinites are associated with chlorite-, talc-, magnesite- and amphibole- bearing serpentinites (Fraser, 1967), the forma- tion of which was influenced, at least partly, by the intrusion of the Bogong granite. Lizardite-rich pods of black serpentine up to a few centimetres wide, separated by slicken- sided platy chrysotile, predominate within the sheared serpentinites of the western sector. Additional local variants of serpentinite have been described by Golding (1966) and by Golding and Bayliss (19680). 9. Enclosures in the Harzburgite Enclosures account for about five volume per cent. of the harzburgite. These are (a) the garnet-vesuvianite (Group 1) rodingites, and the “ sub-rodingites ’’, (b) the Haystack Creek metasomites (including the Group 2 rodingites), (c) the acid feldspathic rocks, and (d) the chromitite pods. Groups (a) and (c) (above) account for about 60% and 30% of the enclosures respectively. The apparent structural relations of the enclosures to the harzburgite are indicated in Table 2. (a) The Garnet-Vesuvianite Rodingites These rodingites are pale coloured rocks with a “‘ flinty ”’ or finely sucrose to coarsely gabbroic megascopic appearance. They contain variable amounts of garnet (N=1-700-1-735) belonging to the grossular-hydrogrossular series, vesuvianite, chlorite and relict non-cataclastic diopside, all of which are colourless in thin section. Amphiboles and serpentine minerals are rare accessories. The occurrence of garnet in wehrlite and gabbro (Section 7) is excluded from consideration here. These rocks torm tabular bodies up to 50 ft. long and 3 ft. wide, but usually much smaller, which occupy sub-vertical, usually meridional spaces in massive harzburgite and serpentinite. They are most abundant along North and Central Mooney Ridges and at Mt. Lightning. Some masses are homogeneous, but streaky and patchy mineral segregations occur in others. Marginal slickensides and brecciation are absent or rare. The rocks are similar to those else- where regarded as metasomatized basic dykes (Arshinov and Merenkov, 1930; Miles, 1950 ; Bloxham, 1954; Baker, 1958), but dissimilar to the rodingitized tectonic inclusions within sheared serpentinite (Schlocker, 1960 ; Vuagnat, 1965 ; Coleman, 1966). ay GOLDING PLATE 1 JOURNAL ROYAL SOCIETY N.S.W. ‘asplryy Aouooy, YON ‘oury Sizj, Aouooyy oy} wor (HOVTG) 910 sUTOIYO sAISseUL pue (sperourt outyuedios YyyIM oyturo1y9) 94tyTULOIYO (Ayeoris pue poyods) popurq-uorslTyos sut}josyo pue Surjoosuez, (9}z14YM) SUIDA oISUIPOY—Z “OLT WO Z ‘asply AoUOOTT YFION ‘ouly, YYNOS UvIINA OY} WIOIF eIN90Iq 9JISUTIPOI oyIUIOIY)—'T “DIT THE COOLAC-GOOBARRAGANDRA ULTRAMAFIC BELT, N.S.W. Although lime released during serpentinization possibly contributed to metasomatism, the presence of unaltered diopside in some wall rocks, and the availability of lime in the precursor rocks and magmas themselves, suggest the latter as the major sources of the added lime in the Group 1 rodingites. Many Group 1 rodingite bodies appear to be rootless dykes which represent pockets of residual gabbroic magma, and some, at least, either consolidated and were metasomatized at the observed sites or have been transplanted, together with their wall rocks in larger, fault- bounded, composite blocks from pre-existing sites. 181 The occurrence of a rodingite vein sharply transecting and offsetting magmatic flow layers (Sub-section 9 (d)) in chromitite (Plate 1, Fig. 2) and the previously noted inter-relation- ships jointly indicate that chromitite was the earliest and the rodingite precursor the latest rock to consolidate. While a two-stage origin involving pre- cipitation of gabbroic minerals, followed by rodingitization, is visualized for many Group 1 rodingites, some may be direct precipitates from a more aqueous fluid (Anirudda, 1967), and narrow veinlets of monomineralic chlorite, garnet and vesuvianite in some of _ the chromitites may be related to such a fluid. The TABLE 2 Enclosure Types Within the Harzburgite Infaulted wedges of eastern granite (c),* Structural exotics (mechanically transported) Exogenous Murrumbidgee and Red Hill. ? Fault-displaced segments of marginal granite micro-breccia (c), Keef’s Scarp. Exogenous Composite feldspathic body (c), Tumor- Mush-transported exotics, autoliths, and (xenoliths) roma Road. roof pendants —<——$——— Endogenous Chromitites (d). (autoliths) ? Wehrlite roof pendants east of Mooney Peak. Non-cataclastic granite-aplite dykes (c), Exogenous Patten’s Ridge. Liquid magmatic intrusions and _ rootless ?Variolite apophyses and derived meta- dykes essentially at the site of con- somites (b) at Mt. Lightning. solidation ————————_— Garnet-vesuvianite-chlorite rodingites (a). ‘““ Sub-rodingites ”’ (a). Endogenous ? Wehrlite dykes and apophyses east of (co-magmatic) * (a)—(d) as in introduction to Section 9. Group 1 rodingite dykes and veins frequently transect chromite deposits, particularly in the north of the belt. The intrusive im-situ character of the precursor magma with respect to the chromite host is unambiguous, and rodingite- chromite breccia (Plate 1, Fig. 1) indicates that the chromite was competent when the precursor magma was injected. The rarity of dykes of harzburgite (or serpentinite) in chromitite, and the absence of harzburgite-chromite breccia and of rodingite- harzburgite breccia contrast with the rodingite- chromite associations. These relations reflect marked differences between the physical states of the harzburgite and rodingite precursor materials and between the competency of the chromitite and harzburgite hosts of rodingite. Mooney Peak. Cataclastic acid feldspathic enclosures (c). variable hydration of the precursor fluid is also suggested by tabular bodies of brown horn- blende-prehnite rock and by others containing fibrous (? tremolitic or lamellae-bearing) clino- pyroxene and zoisite. These bodies, here termed ‘“sub-rodingites ”’, were encountered only at Bridle Creek and Mt. Lightning, but may have been overlooked elsewhere since their grey colour differs only slightly from that of the harzburgite host. Although Group 1 rodingites are abundant near the augite gabbro in the Mooney Mooney Range, they are also abundant at Mt. Lightning, where gabbro is lacking. The rodingites and augite gabbros may have derived from the same initial source (inter-cumulus liquid or partial melt), but if so their history diverged. The 182 uralitization and ensuing saussuritization (see Ehlers, 1953; Harpum, 1954) of the augite gabbro did not result in Group 1 rodingite minerals except on a microscopic scale. Con- versely, Group 1 rodingites contain little or no amphibole or zoisite. The alteration of basic rocks in the Coolac belt thus followed three trends: the uralitic-saussuritic, the Group 1 rodingitic, and the Group 2 rodingitic (sub- section 9 (b)). When the mush liquid did not precipitate as gabbroic Group 1 precursor material, it may have split into pyroxenitic or amphibole-rich (‘‘ sub-rodingitic ’’) and feld- spathic (Sub-section 9 (c)) fractions. ihe consolidation of the Group 1 rodingitic pre- cursor, ‘‘ sub-rodingitic ’’ and feldspathic bodies was probably the final event in the bulk coherence of the harzburgitic mass. (b) The Haystack Creek Metasomites Although prehnite- and zoisite-bearing rocks appear in diverse settings (Section 4 ; Section 7, Sub-section (a)) in the belt, the occurrences at Haystack Creek, Mt. Lightning, are the most distinctive. Haystack Creek (Golding, 1966) marks the eastern junction of a mass of variolite about 300 yd. long and 50 yd. wide within the eastern sector. The least altered variolite is megascopically similar to that in the western marginal zone (Section 5), 700 yd. distant, but thin sections show it to be prehnitized. One group of rocks in the creek includes a series of greenish-grey metasomites derived from basic rocks of doubtful status, in which colourless amphibole is the sole constituent in some outcrops but is associated with antigorite ; with prehnite; and with diopside, chlorite, prehnite, clinozoisite and sphene in adjacent outcrops. Another group of rocks includes pale coloured, fine-grained metasomites which vary from homogeneous to gneissic in structure, and include several with relict variolitic texture. Most of these rocks formed at junctions of peridotite or serpentinite either with variolite or with acid feldspathic rocks. Some outcrops reveal up to six metasomatic zonal segregations with vertical junctions. These rocks (the Group 2 rodingites) contain variable amounts of prehnite, zoisite, garnet, chlorite and sphene. They differ from the Group 1 rodingites as follows: diopside and vesuvianite are absent, calcite is present in some, the chlorite is greenish, and prehnite and zoisite are characteristic and occur in substantially monomineralic rocks. The garnet, however, is similar. H. G. GOLDING The metasomatism at Haystack Creek is of the lateral or contact type and may have been promoted by the water which induced serpent- inization in the associated rocks, or by fluids of other affiliations. (c) The Acid Feldspathic Rocks These are streaky grey and white, cherty and fine-grained rocks occurring in small masses similar in size and shape to that of the Group 1 rodingites. They are strongly micro-cataclastic and exhibit micro-faulted and impacted feldspars with bent twin lamellae, intensely sutured quartz — and abundant mylonite. Single samples are not representative of a given mass. Specimens from Keef’s Scarp contain micro- perthite, oligoclase, quartz, leached biotite, rosettes of pale amphibole and zoisite. Plagio- clasite with zoned andesine to oligoclase, muscovite, chlorite, sphene, quartz and zoisite ; and albitite with striated and checker-board albite, chlorite, sphene, leucoxene and (?) stilp- nomelane occur in different masses along Haystack Creek. From a single mass on Red Hill plateau each of eight specimens revealed different assemblages : microcline-, plagioclase-, albite-, chlorite- and carbonate-rich, as well as hornblende-, garnet- and pyroxene-bearing types being represented. Similar enclosures in ultramafic rocks else- where have been regarded as foreign intrusions (Benson, 1913 ; Watson, 1953) or hydrothermal bodies (Francis, 1955), as co-magmatic dif- ferentiates of the ultrabasic magma (Arshinov and Merenkov, 1930; Suzuki, 1953), as co- magmatic and metasomatic members of the “alpine mafic magma stem” (Thayer, 19630, 1967), as metasomatic complements of rodingite (Green, 1958), as metasomatized gabbro (Olsen, 1961), as reconstituted sediments (Baker, 1958), and as metasomatized sediments and volcanic rocks (Coleman, 1966; Leonardos and Fyfe, 1967). Diorites containing zoned plagioclase may be differentiates of the gabbroic precursor magma of Group 1 rodingite. Some other types appear to be metasomatic modifications of this diorite or of gabbro. The reciprocal rodingitization of gabbro at one point and its acid feldspathiza- tion at another seems possible. The cataclasis suggests movement of largely crystalline material during emplacement and metasomatism. Some enclosures may represent fault-displaced segments of marginal granite micro-breccia ; and a composite feldspathic body within harzburgite along the Tumorroma Road is THE COOLAC-GOOBARRAGANDRA ULTRAMAFIC BELT, N.S.W. probably a xenolith derived from the Burrinjuck granite. Aplite dykes associated with the Bogong granite contain micrographic inter- growths of quartz and microperthite and are non-cataclastic. (d) The Chromite Segregations Lenses (pods) of massive and disseminated chromite (chromite deposits, chrome ores, chromitites) up to 200 ft. long and a few feet wide, but usually much smaller, are unevenly distributed within the harzburgite, and over a length of 5 km. along Welch’s Ridge they appear to be absent. Textures indicate their develop- ment in three principal stages: (i) an abyssal or cumulate stage, (ii) a re-emplacement, desegregation or deformational stage when flow-layering and lineation were superimposed on cumulate textures (Golding, 1966, 1967)), and (ili) a stage of metasomatic modification (Golding and Bayliss, 1968a). The principal silicates in the ores are olivine, diopside, serpentine minerals and_ chlorites. These form the matrix of chromite fragments in flow-layered ore, but fill intercumulus spaces, or occupy fractures and breccia spaces in massive ore. The distinction of primary silicates and their derivatives from subsequently intro- duced rodingitic and other material, and from material fortuitously intermixed with, or juxta- posed against, chromite during re-emplacement and tectonism, is thus dependent on the recognition of primary textures which are preserved in small relict portions of ore. The sizes of the chromite and olivine grains in undeformed Coolac ores are significantly larger than those in the stratiform (Bushveld and Stillwater) chromitites (Jackson, 1961, 1963) and point to differences in the duration, depth or other conditions of crystallization. Characteristic compositional features of the primary (unaltered) chromite are (1) the low content (usually <5%) of Fe,O3, and (ii) the large variation in Cr,O; and Al,O,; (Table 3). Chemical analyses of chromite concentrates from 29 deposits and further data based on a linear relation between the Cr,O,: Al,O, ratio and the cell dimensions (Golding, 1966) indicate that Cr,O, varies from 62 to 34 and AI,O, from 6 to 34 weight per cents. There is also a bimodal frequency distribution of the deposits with respect to the Cr,O,: Al,O, ratio, with major and secondary maxima at about 57% and 37% Cr,O, (and 10% and 30% AI,O,) respectively. Of the seven largest deposits, five contain Cr-rich and two contain Al-rich chromite. 183 The Cr-rich chromite is usually associated with mesh texture serpentine derived from olivine in deposits throughout the belt. At Mt. Lightning and at North and Central Mooney Ridges and near the Tumorroma Road, however, these deposits are interspersed with others containing Al-rich chromite associated with diopside or with derived chlorite containing minute garnets. The Cr-rich chromite accumu- lated, and probably precipitated with olivine, and the Al-rich chromite apparently accumulated and may have precipitated with diopside. The greater frequency of resorbed chromite in the Cr-rich, but of relict primary textures in the Al-rich, chromite suggests that the former had a longer history. TABLE 3 Chemical Analyses of Cleaned Chromite from Segregations in the Honeysuckle Range Harzburgite 1 2 3 4 Crow, ee ese 35.8 59.1 59.9 Al,O, pe) 8856 30.1 10.0 5.8 Fe,O, 4.9 Me 4.9\1 iq FeO 8.2 Tie? 1258 MgO 17.4 Wiel 12.4 14.5 MnO 0.2 0.1 0.2 0.2 TiO, 0.1 0.1 0.1 0.2 SiO, 0.7 es 0.3 1.0 H,O 1.0 = 0.1 1.4 Etc. On2 0.1 0.2 = Total ..| 97.6 98.5 | 100.1 | 100.1 a, A+0.005 .. 8.213]. 8.217| 8.312] 8.317 1. Chromite with a little chlorite impurity. Vulcan North Mine. North Mooney Ridge. 2. Chromite with chlorite and traces of relict diopside. Quilter’s South Mine, Mt. Lightning. . Chromite with a little serpentine impurity. Mt. Miller Mine, Tumorroma Road. . Chromite with a small amount of chlorite, serpentine, grossularite and opal. Kangaroo East Mine, Honeysuckle Range. Analysts : Nos. 1 and 3: Mines Dept., N.S.W.; Nos. 2 and 4: B.H.P. Co. Ltd., Newcastle, with a separate determination of FeO (analysis 2) by R. Fisher, Sydney. me Ow The two chemically and wmineralogically contrasting ore types presumably derived pene- contemporaneously from contrasting magmas or magma domains, or at different periods from different magmas or from a magma the chemical and/or physical character of which changed with time. The close proximity at several localities and within identical harzburgite of the two chromitite types suggests that at least one type originated in a different environment from that in which the harzburgitic minerals 184 precipitated, if such minerals are in fact magmatic precipitates (and not refractory residues). It is concluded that some chromite pods at least have a “ primary exotic ”’ relation to their containing rocks. The ore pods may represent fragments of former layers, but their stream-lined shapes (Golding, 1966) and scattered distribution suggest that after isolation the pods were entrained within and re-emplaced with the harzburgitic mush, as proposed by Thayer (1960, 1964), for podiform chromite deposits generally. To some extent, therefore, all the pods have a “ secondary exotic ”’ (autolithic or xenolithic) relation to their present host rocks. The occurrence elsewhere of Cr-rich chromite deposits in feldspar-free peridotite masses and of Al-rich chromite deposits in ultramafic complexes containing feldspathic members was noted by Thayer (1946). The Cr-rich Coolac chromites are similar to those of the Pacific Coast Province (Thayer, 1946). The Al-rich Coolac chromites are similar to those in East Oregon (Thayer, 1946), in Camaguey, Cuba (Flint e¢ al., 1948), in the Philippines (Stoll, 1958) and in the Kempirsay pluton in the south of the Uralian geosyncline (Pavlov and Chuprynina, 1967), all of which are associated with gabbro, troctolite or anorthosite and several of which contain anorthite in the chrome ores. The absence of feldspar or its alteration products in the Al-rich Coolac ores may indicate their formation at greater pressures than those which operated elsewhere (Turner and Verhoogen, 1960, pp. 130-31; Kushiro and Yoder, 1964 ; Irvine, 1967). If the usual sequence from lower peridotitic to higher feldspathic members in stratiform and pseudostratiform peridotite-gabbro com- plexes is applicable to the precursor complex of the Coolac rock association, Cr-rich chromitites originated at lower levels, and the Al-rich chromitites at higher levels (nearer the feld- spathic material). The regional distribution of the Coolac chromitites also points to a relation between the Al-rich type and the more calcic and aluminous members (rodingites, gabbros and wehrlites) of the Coolac rock association. 10. Enclosures in the Serpentinite These enclosures increase westward and include (i) fragmented representatives of the types which occur in the harzburgite, tectonic inclusions of country rock (Section 5) and their metasomatic derivatives, (11) sulphide deposits, (i11) isolated masses of quartzo-feldspathic and HG. GOLDING cordierite - spinel - anthophyllite hornfelses (Golding, 1966), and (iv) certain metagabbroic and wehrlitic enclosures referred to below. A mass of heterogeneous metagabbro about 300 ft. long and 50 ft. wide lies within schistose serpentinite of the western sector along the Tumorroma Road. Some portions are pyroxene- and other portions amphibole-bearing ; fabrics are partly granoblastic and partly igneous and metasomatic (Golding, 1966). Another metagabbro enclosure and also one of wehrlite similar to that in the North Mooney complex occur within serpentinite two miles to the north of the Tumorroma Road (Veeraburus, 1963). These occurrences suggest the former existence in this area of intrusions similar to those in the north of the belt. The serpentinite has moved around these enclosures, the earlier history of which is problematic. 11. Speculations on the Genesis of the Ultramafic Association Assuming the origin of the harzburgite either as a cumulate or as a refractory residue (Section 6), a stage existed when harzburgitic mush formed the lower component and liquid mafic magma the upper component of a bipartite, abyssal mush and magma complex. Its depth of formation (Green, Green and Ringwood, 1967), duration at one or successive depths, and the independent history of the components would have influenced the derived rock association. With a protracted duration, the formation of transitional cumulate mushes of dunitic, wehrlitic or troctolitic character might be envisaged and may be exemplified at the Bay of Islands, Newfoundland (Smith, 1958). If the harzburgite 1s a cumulate, Cr-rich chromite may have accumulated with it and Al-rich chromite may have accumulated with higher level transitional mushes. If the harzburgite is a refractory residue, and provided no chromite segregations derived as such from pyrolite, Cr-rich chromite may have accumulated at the interface of harzburgitic and transitional mushes, and Al-rich chromite at the higher level interface of transitional mush and magma. The subsequent history of an abyssal complex of the second type intersected by the tectonic zone, or its precursor, might be visualized, in outline, as follows: The mafic magma advanced ahead of the transitional mush and the latter, remobilized on ascending to lower pressure levels, in turn preceded the more sluggish harzburgitic mush. Disrupted Cr-rich chromite THE COOLAC-GOOBARRAGANDRA ULTRAMAFIC BELT, N.S.W. segregations, released from the lower interface, were captured by and entrained within but tended to lag behind, the frontal edge of the harzburgitic mush. Al-rich chromite masses released from the higher interface entered the mush later. A second-order vertical zonation of chromite autoliths thus developed within the rising front of the mush. A near-frontal mush zone enclosing Al-rich and the smaller and less compacted Cr-rich autoliths preceded a zone enclosing the larger and denser Cr-rich autoliths which, in turn, preceded barren harzburgitic mush. Of the earlier expressed mafic and transitional magmas, a portion reached the surface through sporadic volcanic feeders and other portions consolidated in sub-volcanic reservoirs. Accom- panying further tectonism, the harzburgitic material continued its ascent and pierced the roots of the earlier intrusions and down-folded portions of the earliest extrusions. Assuming mush re-emplacement doming, or block or slice tectonic uplift of the central part of the belt (between the Adjungbilly Valley and the Tumorroma Road), erosion could account for the observed rock and ore distribu- tion. Thus, near-frontal harzburgite enclosing mixed chromite autoliths, abundant Group 1 rodingites and related enclosures (near the roof of the harzburgite), together with volcanics, gabbro and wehrlite representing the earlier mobilized magmas, are exposed in the north ; but elsewhere have been eroded so as to uncover deeper levels of harzburgite enclosing Cr-rich chromite autoliths, and, in the centre of the dome (Welch’s Ridge-Kangaroo Plateau), the still deeper zone of barren harzburgite. The peridotite-gabbro association of the Coolac belt, according to this interpretation, is a mush- and partly tectonically-re-emplaced and also partly re-intruded abyssal complex in which a quasi-stratiform configuration of mush and magma components at depth was to some extent reproduced but also telescoped at shallower levels. Acknowledgements The author is grateful to the Mines Department of New South Wales and to The Broken Hill Proprietary Company, Australia, for encouragement and for chemical analyses of rocks and chromite concentrates; and to Dr. D. H. Green, of the Department of Geophysics and Geochemistry, Australian National Uni- versity, for helpful comments on the manuscript. 185 References Apamson, C. L., 1957. Reconnaissance Geology of the Snowy Mountain Area. Tech. Rep. Dept. Mines N.S.W., 3, 138-140. ANIRUDDA, DE, 1967. Origin of Rodingitic Assem- blages in Dikes Emplaced in the Ultramafic Rocks of Quebec. Tvans. Am. Geophys. Union., 48, 246 (abs.). ARSHINOV, V. V., AND MERENKOv, B. .. 1930. Petrology of the Chrysotile Asbestos Deposits of the Krasnouralky Mines in the Ural Mountains. Tvans. Inst. Econ. Miner., Moscow, 45, 83 pp. BakER, G., 1958. MRodingite in Nickeliferous Ser- pentinite near Beaconsfield, Northern Tasmania. J. geol. Soc. Aust., 6, 21-35. Benson, W. N., 1913. 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(Received 5 November 1969) ~ be: ¥ i a ' » 7 * ‘ wa ) i 7 A 7 7 = iu “angel a i i th \ heirs Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 189-195, 1969 Radio-Carbon Datings of Ancestral River Sediments on the Riverine Plain of South-eastern Australia and Their Interpretation SIMON PELS* ABSTRACT—This paper deals with the configuration of Quaternary sediments of the Riverine Plain. discussed. The origin of fluviatile sediments and their relationship to the present river system is It is shown that the Older Alluvium of the Plain is relatable to a series of prior streams which are still traceable as a relict distributory stream system. The Younger Alluvium is deposited by ancestral rivers which form a tributary pattern. The ancestral river system displays evidence of three separate phases of stream activity. Radio-carbon datings of wood samples from sediments representative of the three phases are presented. Results substantiate the earlier published relative chronology. A palaeo-climatic interpretation of the presented carbon dates, and those published previously, is put forward. The purpose of this paper is to present new datings of three reliable carbon samples obtained from ancestral river sediments and to correlate these with earlier published dates. With relatively few dates available at this stage, inferences drawn from the limited data should still be regarded as contributions towards an eventual understanding of the region’s geo- chronology. Surface sediments of the Riverine Plain consist of two geological subdivisions: the Older and Younger Alluvium. Sediments deposited by prior streams (Butler, 1950) are the Older AJluvium, while Younger Alluvium consists of the ancestral river (Coonambidgal) sediments. The datings presented in this paper are from the Younger Alluvium. The near-perfect preservation of prior streams on the present Older Alluvium surface in some locations was first taken as evidence for a very youthful age. However, subsequent studies showed that they are of considerable antiquity, and regional stratigraphic studies confirm this. Carbon samples occurring conformably in current bedded sands and gravels of strati- graphically the most recent prior stream beds, gave C14 age determinations of greater than 36,000 years (Pels, 1964a). This determination of age represented the limit of the dating equipment, so that it is not known how much older the sediments are. On the other hand, Langford-Smith (1963) published dates of wood samples obtained from * Regional Research Officer, Water Conservation and Irrigation Commission, Deniliquin, N.S.W. Cc shallow depths in prior streams which indicated a much younger age. He attributed these dates to possible reactivation of prior stream beds during floods or root growth not related to the time of deposition. Regional surveys (Pels, 1964b, 1966) have shown that the ancestral river system quite definitely post-dates the period of prior stream activity. This can be demonstrated generally over the Plain in N.S.W. and is substantiated by soils studies (Butler, 1958). The two papers (Pels, loc. cit.) dealt with the surface configuration of the ancestral river system and_ subsurface geological aspects respectively. Both stressed the geochrono- logical importance of movement along the Cadell Fault which enabled ready determination of three separate phases of river activity. It was shown that there is a non-diverted phase (Coonambidgal I) and two diverted phases (Coonambidgal II and ITI) and that each phase consisted of a degradational and aggradational sub-phase. Carbon Datings Datings of samples collected during the regional survey, which formed the basis of the two earlier papers, have now become available. Results of these datings substantiate the earlier postulations. The radio-carbon datings were carried out by the Department of Nuclear and Radiation Chemistry of the University of New South Wales on samples obtained from sediments repre- senting the three aggradational sub-phases, as follows. 190 COONAMBIDGAL I[ This depositional system has a width of one mile and is clearly delineated on the Cadell Tilt Block near Womboota. It is a filled-in river unaffected by further river activity because of movement along the Cadell Fault. It represents both a downcutting and infilling phase. A carbon sample was obtained from the centre of this system at a depth of 6’ 6”. It formed a layer of carbon conformably interbedded with thin layers of gravel. The site’s location is: Portion 16, Parish of Womboota, County of Cadell, N.S.W. Geographic — co-ordinates : 144 AE, Sample Nor. 67/12 NS. W? 3: Age: Exceeding 28,600 years, 1.e. beyond the limit of the equipment. 35° 54'S. ; COONAMBIDGAL II It is known from stratigraphical evidence and the drastic diversion pattern of the ancestral river system near Mathoura (see Fig. 1) that this system again represents a downcutting phase with subsequent infilling. The fill is now represented by the higher older terrace along the Edward River at Deniliquin. The carbon sample, obtained from a borehole in this terrace, was a fragment of a knotted tree branch and definitely an aerial part. It was obtained from a depth of 40’ in State Forest No. 397, Parish of South Deniliquin, County of Townsend, N.S. W. Geographic 144° 58’ E. Sample No.: 67/14 N.S.W. 32. Age: 24,050+835 years. COONAMBIDGAL III There is a further distinct system of younger alluvium which can be traced adjacent to the Bullatale Creek between Tocumwal and Deniliquin. Near the latter town it becomes superimposed on the Coonambidgal II sediments associated with the Edward River. It now forms the lower terrace adjacent to the Edward River near Deniliquin (for details, see Pels, 1966, p. 34). A deep trench was excavated across the lower terrace during construction of the Lawson siphon. This siphon, which was constructed to take irrigation supplies across the lower flood- plain (terrace) of the river, is restricted to this terrace and an elevated canal was constructed on the higher Coonambidgal II sediments. The carbon sample was a block of wood cut out of a log encountered at a depth of 15’ during co-ordinates : 390/02 (S25 SIMON PELS excavation. Its location is described as State Forest No. 397, Parish of South Deniliquin, County of Townsend, N.S.W. Geographic co-ordinates : 145° OE. Sample No, : 67/13 N:S.W. 33: Age: 9,800-+-200 years. SD° 34S. : The three datings indicate a definite chrono- logical sequence. If the position of the Coonambidgal I sample within the sediments (6’ 6” from the surface) were taken as an indication, it could be inferred that the age of greater than 28,600 years. applies to the final stages of the infilling phase of Coonambidgal I. The second date of 24,050 years would apply to the early stage of the infilling phase of Coonambidgal II (40’ from the surface) and the age of 9,800 years would also represent an early stage of infilling of Coonambidgal III. It is likely that the total phase of infilling occupied a considerable period of time. This point is important when further cor- relations are attempted with other carbon datings from the region. From stratigraphical evidence the sequence of ancestral river activity of the Goulburn and Murray systems is visualized as shown in Fig. 1. Bowler (1967) has published a date for ancestral river sediments associated with the Goulburn River near Shepparton showing an age of 30,600-+1,300 years (N298). It is known that the three phases are super- imposed at this location, and the dated sediments would therefore represent Coonambidgal I. The sample from Womboota (>28,600) could be of similar age, and this lends weight to the mapping of Coonambidgal I as shown in Fig. 1. At the same location near Shepparton, younger sediments were dated as 26,200 and 24,500 years, and these dates again do not conflict with that determined for the Coonambidgal II near Deniliquin (24,050--835 years). As can be seen from Fig. 1, the three phases are superimposed in some locations, but in others become laterally separated. Because of this, it was possible to establish (Bowler, 1967 ; Pels, 1966) that source-bordering sand dunes are common on the leeward side of Coonambidgal II ancestral rivers. From this and other evidence, Bowler dated Coonambidgal II sediments at three further locations (samples N301, ANU29 and N296) (Bowler, 1967), which showed dates of 16,600 +400, 13,500-+700 and 13,400+340 years respectively. RADIO-CARBON DATINGS OF ANCESTRAL RIVER SEDIMENTS WOMBOOTA ~ \ SS \ es s ; : ) | i | e wae ARG. TORRUMBARRY ; KANYAPELLA CREVASS bugs ANCESTRAL RIVER SYSTEM VICINITY OF CADELL FAULT Ee s N 2 STREAM 191 Uy 369 TOCUMWAL os = -~~<" + om x ~Ny ram NUMURKAH Cp DEPOSITIONAL PHASES OF COONAMBIDGAL INDICATED THUS 1 1~ =-- Ca SITES THUS +300 FiGurRE. 1. The known dates of Coonambidgal II sediments therefore range from 26,200 to 13,400 years. A further series of dates quoted by Bowler and ranging from 8,320+160 to 4,200+130 years appear to represent Coonambidgal III sediments of the Goulburn ancestral river system. Bowler and Harford (1966) described sample N153 as having been derived from _ the Kanyapella prior stream. The present author suggests that this is a crevass-type stream which can be traced as leaving the final deposition of the third phase ancestral Goulburn (Coonam- bidgal III) and returning on to it as a continuous trace. | Except for the source-bordering sand dunes, deposition during the aggrading phases was generally restricted to the old river channel (valley fills in meandering valleys), but there 192 are isolated instances where crevass-type traces lead from, and return to, the aggraded ancestral river. Such stream traces also occur along the Billabong ancestral river (Pels, 19640). The age of the crevass-type Kanyapella stream sediments is 4,200 years (N153) and represents the final sedimentation of this phase. The combined dates therefore indicate that Coonambidgal III sedimentation took place between 9,800 and 4,200 years ago. It should also be mentioned that in an extensive older alluvial environment’ the meandering valley walls may, in some locations, no longer be discernible, and this has given rise to confusion in the nomenclature used in papers on the Riverine Plain’s geomorphology. One instance of this is the naming of the “ Tallygaroopna prior stream ”’ in the Goulburn Valley by Bowler. This is clearly a deserted ancestral river and is again described as such in a later paper by the same author (Bowler, 1967). The only dating which does not fit in with the discussion so far and the sequence depicted in Fig. 1 is Bowler’s N306 age determination, which, from the locations description, should represent Coonambidgal I (see Fig. 1). In view of the dates obtained from Womboota and Shepparton the age indicated by this sample, 20,900-+-500 years, is not acceptable as it is now known that this phase was diverted prior to at least 26,000 years B.P., as indicated by the age of sample N299 from Coonambidgal II sediments near Shepparton and by sample NSW3z2 from phase II sediments near Deniliquin. The younger date of sample N306 could be accounted for by root growth at that time. Interpretation The correlation of carbon datings with events which created the present configuration of alluvial sediments can only be tentative. However, sufficient information is now available to warrant an attempt to draw up a geo- chronology and to draw from it palaeoclimato- logical inferences. This information includes, apart from the C14 datings, (i) the clear diversion pattern of ancestral rivers around the Cadell Fault, (ii) the readily recognizable surface expres- sion of these former river systems, (i11) the widely separated independent courses of the river in some locations and super- imposition in others. In earlier papers it has been stated that downcutting of a river channel is thought to SIMON PELS occur under relatively pluvial conditions and infilling under more arid conditions. This is the majority of opinion in the world literature on climatically-induced terrace levels of misfit rivers. Recent work by Schumm (1966) gave similar conclusions from morphological studies of ancestral river and present-day river channels of the Murrumbidgee River. Whitehouse (1940) discussed the common occurrence of three terraces along the major rivers in Queensland. Taylor and England (1929) described three terrace levels with differing soil development along the lower Murray River near Renmark. By applying the same reasoning to these investigations, it has been inferred that the three aggrading phases took place under more arid conditions and that the last phase concluded approximately 4,000 years ago. The present river represents a further down- cutting phase. It is to be noted that the three phases were of decreasing intensity, as shown by the dimensions of the respective ancestral rivers. Figure 2 shows, in diagrammatic form, how the sequence of events is visualized. Before any carbon datings were carried out, there was evidence to suggest that a recurring process of degradation and aggradation occurred. Carbon datings have now supplied corroborating evidence and have given some indication of the time spans involved in these sequences. Present results are at variance with conclusions by Bowler (1967), who states: “‘ These two drainage systems (Coonambidgal I and II) are seen rather as part of one single phase of high discharge during glacial times. The notion that tectonic interruption occurred just at the conclusion of one pluvial-arid cycle and before the beginning of another, is not yet sub- stantiated.” It is reiterated that a fully aggraded river channel (Green Gully) was tectonically uplifted and that the subsequently newly created diverted ancestral river now also forms a deeply incised and subsequently filled channel, thus indicating that consecutive pluvial-arid phases were responsible. Recurring climatic fluctuations can be traced further back into the geological history of the Plain. Sections bored through prior streams (Pels, 1964a) commonly show a distinct vertical break from sand and gravel at the bottom of the stream bed to heavy clay. This abrupt break, together with characteristic shapes of incised channels, indicates that prior stream phases also com- RADIO-CARBON DATINGS OF ANCESTRAL RIVER SEDIMENTS menced with downcutting which was followed by aggradation. However, unlike ancestral rivers this aggradation was not restricted to the incised channels but eventually extended beyond the channel banks by lateral overtopping, giving rise to widespread lateral distribution of stream bed, levee and floodplain sediments so typical of prior streams. 193 limited drainage at that time from the region. It appears to have been a large inland area of sediment accumulation. The extensive nature of the prior stream systems and the large quantities of sediments involved indicates that large-scale erosion in the highlands and deposition on the Plain were parallel processes. POSSIBLE INTERPRETATION OF GEOLOGICAL EVENTS re MORE PLUVIAL ar ren 2 DERIVED FROM C14 DATINGS | a | = z a i Saar al x o| a Oo he el 3 28 z rs z TO OF Os alle | pao o]w 6 w Cor a | slo Oo @ AOD a 3" MEAN CLIMATE —= ‘———— - --- rm =) E eo oe = Zz a Se O71 som td je) 23 ona NS a yp cn i = a ae ON FOOD 2 Oem aie uy oO = tt Ow a Ss Es Le ea oo9O re) a cee O SQ2q0n 6288 ao poe E o 2 p2eaeoc Ha Base oF < TS ttoma&a g 283 3 eae SSE a -Foao &®& r (eocs 2 E ALR ee foe g < = ane aN ul IO < oO O 88 3 fo O < @ MORE ARIO YEARS BP 50000 45000 40000 35,000 30,000 25000 20000 15000 10.000 5000 oO FIGURE 2. The pattern of prior streams over the plain is not visualized as having been actively depositing simultaneously, and several phases of deposition and diversions to lower lying areas are probably responsible for the present distributary pattern of prior stream traces (see Fig. 3). The definite change from prior streams to ancestral rivers warrants further consideration. It represents a major change in the drainage system of the region. The distributary pattern of prior streams over the Plain and its dissipating nature towards the west suggests that there was very This is in contrast with evidence shown by ancestral rivers. From the general occurrence of terraces along the entire river, it is clear that the process of degradation (and later aggrada- tion) was synchronous along the entire river course. Terraces are common along the Murray River in the upper reaches and also in South Australia. Where they are absent in the central sector, they have been accounted for as deserted floodplains. distributory pattern, the prior streams form a while ancestral rivers Furthermore, form a tributary system (Fig. 3). Such an overall change in the behaviour of rivers and streams suggests a drastic change in 194 30 Miles _———— ee ears 0 50 Km WD Lunette =) Lake CSE" Prior stream 2° Ancestral river Source borderin SD Sand dunes ° Mallee Foothills SIMON PES aN : ae Meee er one ean SS :: ON urrUum biG she Ree ee ° — Narrandera’€ fi ese . @ FIGURE 3.—The Riverine Plain in New South Wales. (Drawn by W. Mumford, A.N.U.) the drainage system of the Plain and there is evidence to substantiate such a postulation. The western fringe of the Riverine Plain consists predominantly of heavy-textured fluviatile sediments, indicating semi-lacustrine conditions of deposition and evaporite accumulation. It contains numerous lake and lunette relicts and Mallee outliers. Prior stream patterns generally dissipate before reaching this zone. Surface water penetrated the lower lying areas of the Mallee, and chains of lakes are known to have occurred where the present Murray course is now located. There are remains of lunettes adjacent to the river, and RADIO-CARBON DATINGS OF ANCESTRAL RIVER SEDIMENTS preserved lakes occur in its vicinity. The great chain of lakes at the end of Willandra Creek, which branches off the Lachlan River near Hillston, forms a similar set of landscape conditions. The absence of older alluvial (prior stream) sediments along the Murray River west of Wakool Junction suggests that this is a “ post- prior stream ”’ course which now drains the area. The creation of this drainage channel from the region would account for the change-over from a distributory-prior stream system to a tributary ancestral river system, and would explain the present rivers of transit being unrelated to the Plain’s surface sediments. It further explains the increasing salt status of the Riverine Plain’s soils towards the west and the occurrence of an otherwise anomalous vast area of alluvial deposition along, what is now, the middle reach of the Murray River system. References Bow ter, J. M., 1967. Quaternary Chronology of Goulburn Valley Sediments and Their Correlation in South-eastern Australia. J. Geol. Soc., 14 (2). 195 Bow te_er, J. M., and HARForD, L. B., 1966. Quaternary Tectonics and the Evolution of the Riverine Plain near Echuca, Victoria. |. Geol. Soc., 13 (2). BuTLER, B. E., 1950. Theory of Prior Streams as a Causal Factor in Soil Occurrence in the Riverine Plain of South-eastern Australia. Aust. J. Agric. Res., 1. Butter, B. E., 1958. Depositional Systems of the Riverine Plain of South-eastern Australia in Relation to Soils. Soil Pub. No. 10, C.S.I.R.O., Australia. LANGFORD-SMITH, T., 1963. Murrumbidgee Plain Series, N.S.W. Radio Carbon, 5. PELs, S., 1964a. Quaternary Sedimentation by Prior Streams on the Riverine Plain South-west of Giitith, N-S.W. J.and Proc. Roy. Soc. N.S:W. OF: PELs, S., 19646. The Present and Ancestral Murray River System. Aust. Geogr. Studies, 2, 2. PELs, S., 1966. Late Quaternary Chronology of the Riverine Plain of South-eastern Australia. /. Geol. Soc. Aust., 13, 1. ScHumM, S. A., 1966. The Changing Hydrologic Regimen of the Murrumbidgee River. Proc. Symp. on the Geomorphology and Palaeohydrology of the Riverine Plain, Griffith. Taytor, J. K., AND ENGLAND, H. N., Survey of Block E (Renmark) (Chaffey) Irrigation Areas. Bull. Australia. WHITEHOUSE, F. W., 1940. Studies Geological History of Queensland. Papers, Dep. Geology, 2 (N.5S.), 1. 1929. O. .... (A) To correct his mistake, Kilmister and Tupper (1962) considered the expectation value y of the potential per unit charge with a Gaussian distribution function. Defining a _ non- Coulombian potential ), by i. . = i> —v(7), OO Oe OeOnO OO Oe > tho (2) they found a remarkable approximation hee exp (—1-177/25). The error was <0-004 for 0<7r<1-5/+/A. The formula (3) is, of course, of the form of a Yukawa potential. It seems, however, that there is little connection between the above result and the argument of Fundamental Theory. In the latter, a meson is a decaying object associated with the transition from an unrestricted energy state (presumably, of an atomic nucleus) to a stable, symmetric con- figuration (Klotz, 1969). This can be regarded as a scattering experiment in which the scattering agent is a spherically symmetric, impenetrable region of the ordinary three-dimensional space and radius 7). It is essential for the scattering centre to be represented as if it had no field of its own, since the stabilization process of Funda- mental Theory has no location in the physical space-time. The “ impinging ”’ particle is then equally likely to be anywhere within r>7%, but it cannot penetrate into the region r<7%. Let us consider now the conditional prob- ability P, of an event u>x-+dx, whenever u>x. If the frequency function of wu is f, __ Probability (u>x-+dx) c yas Probability (u> x) f(z)dz Suppose now that no additional information is to be derived from u>x%-+dx% as long as u>x. Then (1—P,) is proportional to dx. .. (5) Hence we can write where a is a constant. For continuous and differentiable f, therefore, f (%) =fo exp (—ax). Since f is a distribution, | ; fdx=1=fpla. Therefore (0a) OR OXDs (000 ee (7) If we associate the above probability distribution with a charge (electrical or mesonic as the case may be), the potential must be a function of the form Cee ee (8) Hence, when q has the frequency distribution (7) we obtain a Yukawa potential Go EXP (—1/1»). (9) Sat ee This shows that it is possible to set up prob- abilistic hypotheses within Fundamental Theory, which conform to the known facts relating to the meson fields. Eddington’s Gaussian distri- bution now relates only to the connection between cosmology and quantum scale physics. References EppInGTon, A. S., 1946. Fundamental Theory. Cambridge. Kilmister, C. W., AND Tupper, B. O. J., 1962. Eddington’s Statistical Theory. Oxford. Kotz, A. H., 1969. Jl Nuovo Cimento, 63B, 309. (Received 13 March 1970) Communicated by Dr. A. Reichel , * i Journal and Proceedings, Royal Society of New South Wales, Vol. 102, pp. 203-218, 1969 The Energy Storage of a Prescribed Impedance * W. E. SMITHT Argonne National Laboratory, Argonne, Illinois ABSTRACT—The problem of inferring the total average energy storage of a passive linear electrical impedance from its observed or specified terminal behaviour alone is discussed. Only in a few special cases is the energy storage (for sinusoidal external excitation) uniquely determinable. A general expression, for the energy storage is derived which involves, in addition to terminal properties, properties of a set of functions describing the separate dissipative processes. This expression is used to find a new minimum energy storage for a lumped-element network which all realizations of the impedance must equal or exceed. There exists a minimum energy synthesis storing minimum energy at all frequencies, which corresponds to minimum phase shift Darlington synthesis of the impedance. This minimum energy storage synthesis can be realized provided gyrators can be employed. I. Introduction When a linear passive network is excited sinusoidally there is generally a storage of electro- magnetic energy by the reactive elements. Assuming the terminal behaviour is known, the question may be asked: to what extent is the physical energy storage of the network determined by the terminal behaviour? Alternatively: what can be inferred about the energy storage of a network from measurements of its terminal behaviour alone? To be specific, we consider the impedance Z,(#) of a hypothetical linear, passive one-port to be given for all /=7w, and examine the possible corresponding energy storage from excitation by a r.m.s. current Ip. If Z,(f) is a pure reactance, it is well known (Bode, 1945, sec. 9.4 ; Maa, 1943 ; Montgomery et al., 1948 ; Pannenborg, 1952) that the energy storage for a given sinusoidal excitation is uniquely determined. Also, if Z(H) is known to result from a reciprocal network containing only two kinds of elements the energy storage is also easily shown to be unique (Section III). However, it can be seen that in the general case the energy if not fixed by Z,(f) alone. Suppose we have a particular network realization of Z)(f) which is assumed not to be a pure reactance. Then any resistance in this realization which is dissipating power may be replaced by an all-pass network terminated in a resistance, or some other combination of reactive and resistive elements which behaves terminally as a resistance (e.g. Cauer, 1958, p. 53), without changing the terminal behaviour Z,(p) of the network as a whole. (If distributed circuits are introduced each resistance may be replaced by a loss-free transmission line of arbitrary length terminated by its characteristic impedance). Although Z,(/) is unchanged by this transformation, the energy storage is changed (increased) by the introduction of additional reactive elements. Thus it becomes clear that the energy storage of a system described by the general impedance Z,(p) depends upon aspects of the internal structure of the network, in striking contrast to the purely reactive case. In other words the energy depends upon the particular realization of Z,(), and terminally equivalent networks are not necessarily equivalent as far as energy storage is concerned. By the above procedure it is possible to increase the energy storage associated with a specified dissipative impedance Z,(f). This suggests the existence of either a minimum possible energy storage at a particular frequency or a minimum energy realization over all frequencies. Both of these conjectures are shown to be true. For systems containing no non-reciprocal elements (as typified by gyrators) a simple lower bound exists for the energy (see Section III) at any frequency p=1w. * Work performed under the auspices of the United States Atomic Energy Commission. + Permanent address: University of New South Wales, Sydney, Australia, 2033. 204 W. E. SMITH However, if non-reciprocal (i.e. gyrator-like) behaviour is exhibited by the network this minimum energy expression is not applicable (Smith, 1967), and a lower energy may sometimes be possible. In Section VII the minimum possible energy is found and it is shown that a minimum energy realization by Darlington synthesis is always possible provided gyrators are employed. The natural requirement for gyrators to obtain the minimum energy network is somewhat curious but it is demonstrated that in general they are essential. In Sections II and III some elementary observations on equivalent circuits and particular results for special cases are noted. In Section IV general expressions are obtained for the energy storage which involve internal functions associated with the energy dissipation. For the special case of a reciprocal network for which Z,(p) is specified as a function of the magnitudes of the individual resistances, Vratsanos’ theorem may be employed to deduce the energy uniquely (Section: V). The energy storage of networks with one resistor is treated in Section VI. This case, although special in itself, occupies a central role in showing the existence of a minimum energy and a minimum energy storing network (Sections VII and VIII). In Section IX a very simple example is discussed at length to illustrate points in the main body of the paper. The discussion is oriented towards lumped-element systems because this is where synthesis methods are available, but much of it is not necessarily restricted to this case only. Energy storage is interpreted to mean the total average physical energy storage resulting from the excitation. In a complex system this may not be entirely electromagnetic energy ; for example J and V might both contain a mechanical energy component in a dispersive system (Smith, 1967). The microscopic distinction (Tonning, 1960) between purely electromagnetic and other forms of energy is not made here. II. Some Remarks on Equivalent Circuits The term equivalent circuit is well entrenched in the literature with the meaning of equivalent terminal behaviour or equivalent with regard to exterior behaviour. We have seen in I that equivalent circuits in this sense need not have the same energy storage. Objections to the use of the term “ equivalent’ to apply to the terminal behaviour alone have been made before and Gross and Braga (1961) have suggested the use of “‘ pseudo-equivalent ’’ to emphasize the terminal equivalence only. The use of the term “internally equivalent ”’ is suggested to imply not only equivalence in the usual sense but also that internally equivalent networks have the same average magnetic (kinetic) and electric (potential) energy storages T, V and power dissipation P for similar excitation. The need for the specification of both T and V rather than the total energy (T+V) arises because of further complications with non-reciprocal (gyrator containing) networks. It is easily shown (Balabanian, 1958, sec. 1.6, 1.7) for reciprocal networks that [pl pZolio\=2io(T—V)4P ..... 5-5 eee (1) where J, is the r.m.s. excitation current of Z, at f=tw. Thus T—V=Iol,X,(iw)/20 2.2... eee (2) so that for a specified impedance T and V are both fixed when the total energy W=T-+-V is known. Thus reciprocal equivalent networks having the same total energy are internally equivalent. However, since Eq. (2) is inapplicable to gyrator-containing networks (Smith, 1967), the same total energy does not imply the same T and V for a given impedance. The term equivalent network was also used by Cauer (1958, Chap. 10) in describing a trans- formation which formed a set of networks having the same terminal behaviour. We shall show that Cauer’s equivalent networks are also internally equivalent. Suppose the ~ mesh equations of a reciprocal network are FIV os Me (3) V V-/0 | Mane (4) 0 0 where V is the voltage source exciting the network in the first mesh only and I is the mesh current vector. Z has the form L=PpL4+R+-D/p 2.2.15 4. eee (5) ENERGY STORAGE OF A PRESCRIBED IMPEDANCE 205 where L, R, D are constant real symmetric matrices. The Cauer transformation transforms the mesh currents I to I’ through the non-singular, real, constant, transformation T ee Meee tet Pic ta elec tale eee oan (6) If T is required to have the first element of the first row equal to 1 and all other elements in the first row zero, Cauer shows that an 7 mesh network having the mesh impedance matrix 7 eens) WET LS AT ee ae a ee a oe ee CE (7) will be an equivalent network. For f=1w it is easily seen that the energy of the original network is given by Oi — Oey (O24 Cp \pai lt aie een in ie autre elena. (8) =]'tT7(@Z/0p)p=i0Tl’ (from (6) and T real) ........ (9) = \ciop(F’ZE) baal (2 Constant) 2072. 4...4224 (10) = OZ 0) Lai tise tall 1(1))))) ergeetsiiect radars, eos eee (lah) a Re A) | ee Tee ty er rer ee or re (12) where W’=T’+V’ is the total energy of the equivalent network for the same excitation. Since we are considering only reciprocal networks, this implies that the Cauer equivalent networks are internally equivalent. III. Energy Storage in Simple Cases Two elementary cases where the energy storage is unique are reviewed. Another special case will be discussed in Section V after general expressions for energy storage are derived. (a) Loss-free Networks For loss-free networks, i.e. Z)(p) a reactance function, the energy storage is given uniquely by (Bode, 1945, sec. 9.4; Maa, 1943; Montgomery e¢ al., 1948). W=TAV=$hlolp(OZ[Op)oatn. vce e eee e eee eeeeee (13) Bode remarks that Eq. (13) implies that the total volt ampere rating of the elements in a reactance network is independent of the manner of synthesis. Thus from (13) and (1) the following proposition applies for reciprocal networks. All equivalent reciprocal reactance networks are internally equivalent. For non-reciprocal networks Eq. (13) for the total energy still applies (Tonning, 1960; Smith, 1965; Carlin, 1967), so that equivalent reactance networks store the same total energy. However, because Eq. (1) no longer applies this does not imply equality of the magnetic and electric energies separately. (b) RL and RC Circuits and a Simple Bound for Reciprocal Networks If the network is known to be reciprocal, Eq. (1) applies. Further, if it is also known to be either an RL or RC network, V or T respectively is zero and Eq. (1) gives Plea mea a | aie EXC De est ee (14) Notice that it is not sufficient for 2)(f) to be of a form for RL or RC synthesis to be possible (e.g. Balabanian, 1958, sec. 2.3, 2.4). The network itself must actually be an RL or RC synthesis of Z)(p). When this is the case, Eq. (14) shows that the energy storage is again independent of the details of the network synthesizing Z,(p). For example, the two Cauer canonical forms and the two Foster forms (Balabanian, 1958) will all store the same energy, and this will be the same as for any other two-element kind synthesis. Thus the problem of energy storage for two-element kind reciprocal networks or for loss-free non-reciprocal networks is easily solved uniquely. For reciprocal RLC networks Eq. (1) may still be used to give a bound on the energy at any particular frequency EVA Ses ie iy [eg 2ae sree ees ee (15) For RL and RC networks this bound is attained at all frequencies. This bound is not applicable to non-reciprocal networks, and it will be shown in Sections VII and VIII that the absolute minimum energy storage may well be less than that given by (15). D 206 W. E. SMITH IV. General Expressions for the Energy Storage | It will be shown that the average energy storage may be written in terms of the reactive behaviour of the impedance, and a set of causal frequency-dependent functions describing the several dissipative processes. The energy storage expression may be obtained conveniently in — two ways: (i) by writing out circuit equations so as to treat the network as a reactive -port, the energy storage of which is known (Maa, 1943), together with the resistors causing the dissipation ; (ii) by considering energy conservation for a terminal excitation exp (tw-+o)t with o—0. The first type of argument has been used by Kishi and Nakazawa (1963) in their paper relating group delay and energy storage. The second method, an adaptation of the methods of Cauer (1958, Chap. 4) for proving the positive real character of impedance functions has been used by Tonning (1960) and Carlin (1967) to find the energy storage of reactances. This method has the virtue of being independent of the nature of the system and is not restricted to lumped-element or reciprocal systems. Suppose the impedance Z,(f) is excited by a current which has the instantaneous value Gy=Re (4/21, xP Pl}. . on aa ssa. (16) with p=iw+o, G70 2060. 1 ae (17) The instantaneous voltage across the impedance is then WY p= Re (1/2 Z,(P)1, exp (pt). 2 ae eee (18) Since the only sources of energy dissipation in the impedance are the resistances, we can write the following instantaneous energy conservation equation (Power supplied by the excitation) =(Power used to increase energy storage in the impedance) -+(Power dissipated in the resistors). ........ (19) The impedance is supposed to be in the quiescent state (zero energy storage) at t=— oo. To find the energy stored at time é for this excitation, we must integrate Eq. (19) from t=—oo to i=1y. "(total energy supplied by the excitation) =(energy stored by the network) +(energy dissipated by the network) .. (20) We now introduce the functions /,(f), IAP=HA AP) fo) se eS ee eee (21) where J,(p) is the complex current in the At resistor R, for the excitation (16). Le. J, —Re {4/21 ,(p) exp ot! fase. 1 (22) =Re {V/2f,(P)Io exp pt} is the instantaneous current flowing in the k* resistor. Notice that the current 4, is causally derived from the excitation current, so /,(p) is a transfer function analytic in the right half of the bp plane. This analyticity extends on to the imaginary # axis since the dissipation in each resistor must remain finite for finite J). /,(f) 1s also a real function of #. If W(t.) is the energy storage at time t=/), Eqs. (19) and (20) become VF dW (tS IFLR, SS ee (23) k to bo { V >I dt=W (t,) +2 R, J Zdt i+0. The average energy is then obtained by averaging over a full cycle 27/@. The terms requiring special consideration are those having 2o as denominator. Write Zip) ERPS) ot tee os Ooo cee. eat aes (28) Then for small o, Z)(p), being analytic, may be expanded as a Taylor series about /=7w provided p= is not a pole of Z,(f). Then Ry(tw+o)=Ry (tw) +(AR,/dc) c tO; inst OLder IN Gun. a4scsu eee (29) p=10 Further, f,(p) is also analytic, so AAbfa() =felieo)filin) +o-2( fai; ease tor cist Order iwc eee te ee (30) Furthermore, in the steady harmonic state the total dissipation I,JjR,(iw) is equal to the sum of the powers dissipated in the individual resistances R,. Le. I1oR,(iw) =ZR, f(t) POCO “eye Aen Mee eae (31) After substituting (29), (30), (31) in (27), the limit c->0 may be taken to give Re {Z,(iw) [ge2#/2iw} +41 ,1o(@Ry/00)p=ie =Wt) +E Ry[Re {(fylieo)Io)?e?"/2ie} +40/Oo(f,fa)p=iol glo]. .- +--+ (32), Thus W(t) =Wolo(@Ro[8) p= io —ToLoER, 9/80 (ffs) ia +Re {Io( Zy(ie) UR filiea)) e%"/2i00)). eee eer ere ee (33) __ The average energy storage W(t)=W=T-+-V is found by averaging over a cycle 27t/w giving W=Bolo(ORo|A6)p—io — Holo DR, /20 Wein * Dp ti a (34) Since the impedance Z,(p) is analytic, the Cauchy-Riemann equations may be used to write ie (ORo/00)p=iw=(OXp/OW) pain. oo. eee eee ccccccee., (35) 0/Ao(f,.fr)p—io=2(Re f,)0/A0(Re f,) +2(Im f,)8/do(Imf,). .....20..-.. (36) But /,(f) is also analytic, so using the Cauchy-Riemann equations 0/Oo(f,.fr)p-io=[2(Re f,)@/Aw(Im f,) —atlin 7 e/eCm(Re fi \ipsto 6.23 ens. seen ens (37) =2[(Re f,(—p)) Im (0f,(P)/@@) +(Im f,(—p)) Re (Af,(f)/Aa)]p—io. .. (38) Since f,(~) is a real function of pb. =2 Im (fx) Of (P) 0c) p =o re ay rte heck Wei Bn hte BM (39) =e NE gl NP) pases taster calihs oy a halls ose. Snx eM (40) 208 W. E. SMITH Substitution of (35) and (40) into (34) gives W=1I,190X,|0w —1lo=R, Re (f(—p)falp))pzio. (41) The dissipation is more conveniently described by the real causal functions Fy (p) = Ri (D) os ose eons ts - (42) Ro(ie) =2F, (i) Fi(io) = EF, (iw) F, (i) (43) so that (31) becomes and the total average energy expression is W =41,190X,/0w 110% Re (Fj(—)Fi(p))pai0. Ue (44) This equation may also be obtained from Goubau’s version of Eq. (34) (Goubau, 1961) by a similar manipulation. For loss-free systems the F,, if any, are all identically zero, and Eq. (13) is recovered. Equations (44) and (43) also show, however, that if the resistive component of an impedance vanishes at some frequency (as for a minimum resistance impedance) the energy storage at that frequency is given uniquely by Eq. (13). Otherwise the energy storage depends upon the properties of the functions F,(p) describing the dissipation processes. Similarly, by considering the one-port as an admittance Yo(P) = Goh) 7B) 0 oad ok eos in ee (45) W=$V V9 B80 —VoV oz Re (A) Fi(P))pqin o- -eea (46) where V, is the complex r.m.s. excitation voltage and YW (P= Re Vi (DV, 8 ee (47) are real causal transfer functions describing the dissipation. Clearly, the ‘Y’, and F, are related by Vi ADDY (p) 2p): Gs 32 ee (48) Equations (44) and (46) are algebraically equivalent at all frequencies =7w except for poles or zeros of Z,(f), where the differentiations and substitutions are invalidated. Finally, a scattering matrix version of (44) and (46) also exists which does not have the singular frequencies on the f=17m axis. Let S,(f) be the scattering matrix (one-dimensional) of the impedance Z,(/). Further, let So,(p) be elements of the scattering matrix S of the network as a whole where the o-port constitutes the given port Z,(f) and the k*-port is terminated in the kth resistor R,. The S matrix is normalized to the resistances R, terminating the ports. Two properties of S are important here. (i) Since S describes a loss-free system it is unitary. (ii) The elements of S are real analytic functions of p for Re p>0 (causal behaviour). A similar energy conservation argument to that used for deriving (44) gives W = —a,ao Im {S,(—iw)AS,(iw)/@} —ayay Re {ESpu(—teo) Soa(iea)} cee (49) where a ao is power incident on the one-port. In obtaining (49), the unitarity of S occupies an equivalent place to (31) or (43) in obtaining the impedance form (44). The scattering matrix form (49) for the energy storage is essentially the same as that derived rather differently and under more restricted conditions by Kishi and Nakazawa (1963). Notice that the present derivations of Eqs. (44), (46) and (49) are not restricted to circuits containing only reciprocal elements. Neither are they intrinsically restricted to lumped-element circuits since only general analytical properties of the immittance functions are used. However, for a continuum of dissipative processes the summations over the & resistors must be replaced by integrations over the volumes in which dissipation occurs. The expressions (44), (46) and (49) for the energy storage, as expected, all involve some aspects of the internal structure of the one-port. The derivation has been a complementary one in which attention has been concentrated not on the mechanisms of energy storage, but on the mechanisms by which energy is not stored (i.e., dissipated). The results thus involve properties of the way in which energy is dissipated in the network as typified by the functions F,(#). Apart from general ENERGY STORAGE OF A PRESCRIBED IMPEDANCE 209 transfer functions conditions and the overall loss condition (43), these functions are arbitrary and depend upon the exact realization of the one-port. The three forms (44), (46) and (49) all have the same content except for the inappropriateness of (44) or (46) at poles or zeros respectively of Z,(p). Equation (49) is the most general in this sense since the scattering matrix formulation avoids these problems. However, in other ways the impedance or admittance forms are more closely related to conventional language and synthesis techniques for one-ports. Thus Eq. (44) will be regarded as the basic expression for further development, although with some modifications similar arguments could be based on (46) or (49). One fact that is immediately apparent from (44) and (13) is that if Z)(f) is not a minimum reactance impedance (1e., it has simple poles on the f=7w axis) the energy storage is the same as that of two impedances excited by the same current, one impedance being the minimum reactance part of Z)(f) and the other a pure reactance corresponding to the non-minimum reactance part of Z,(p). The f, and hence the F, of the resulting minimum reactance impedance are the same as for the original Z)(p). Thus at our convenience we need consider only minimum reactance impedances, the energy storage for a non-minimum reactance impedance being obtained by the addition described above. V. Application of the Vratsanos Theorem Although the separate dissipation transfer functions F, are not usually known, if Z,(p) is known as a function of the magnitudes of the separate resistors R, in the network, Vratsanos’ theorem (Vratsanos, 1957) may be used to determine the energy storage uniquely. This approach is limited further to reciprocal networks only, since Vratsanos’ theorem is valid only for reciprocal networks. Suppose Z,(f) is given as the functional form Z,(/,R,), where the R, are the actual magnitudes of all of the resistors in the network. Then Vratsanos’ theorem states that THIG SOL OR. audattee see bok ae Bases (50) Nxee fi—oZ.iok, trom) 402....2.555 4.05 (51) or Fi=R,0Z,/0R, from (42) .............. (52) NAS Rea@Z,(0 Imus) sea. gia anes oe te (53) or if we introduce the sensitivity S, of Z, with respect to R,, Le. s _alnZ, R, AZ, Pacman Re ro ee ge ES ee aeons nee eee (55) Thus the Fz; may be determined from (52) or (53) and used to evaluate {Re (F,(—iw) F,(io)) k for substitution into Eq. (44) for the energy storage. Lee. F,,(—iw) F; (io) =3[(8Z,(—iw)/@R,)/(8Z(iw) /OR,) }202Zq(iea) |Oiwd ha tey «Gia arcr eee eyo (56) In principle only the dependence of R,(iw) on the R, is essential. From (53) IRe(7 ta) A —=O Gone ING sae, ae we aes esses (57) and since F’,(p) and hence (/’,(p))? is analytic and finite for Re (f)>0, the conjugate Im (F,,(iw))? may be found from the Gewertz or Bode procedure (Balabanian, 1958, sec. 3.6) for rational functions, or by a Hilbert transform (Bode, 1945, Chap. XIV). Notice also that Ag(100) — PF A 10) F,(0) =E| AZ p(iw)/OIn Ry]. eevee veces (58) 210 W. E. SMITH VI. Energy Storage in Networks with One Resistance A network containing a single resistance is the simplest case of a network which can represent a general impedance Z,. Darlington synthesis (Balabanian, 1958) shows that any lumped-element ~ impedance can be obtained from’such a network. Apart from being a simple special case, this type of network occupies a central position in demonstrating that a minimum energy storage exists and that a minimum energy synthesis is possible. Since the system contains only one resistance, the dissipation is described by a single F,(p)=F(p) and Eq. (48) is simply R,(iw) = F(—iw)F(iw)=F*(iw)Fliw) ......... eee eee (59) and the energy storage (Eq. (44)) is W=T+V=HI,100X,/@w—I,Io Re {F(—iw)F’(iw)} ........006. (60) =41,Ip0X,/@w —I,IpR, Re {F'(iw)/F(iw)} using (59). ........ (61) For a lumped element network F(f) can always be written as a product of a unique minimum phase shift function Fmin(f), having no zeros in Re f>0 and satisfying Eq. (59), together with a non-minimum phase shift factor, 1.e. (pb) =F min(P) UN ( —P,)/(B +P x)" +020 s eae (62) where M, is the multiplicity of the zero of F(f) at f=, and RE BO. 5 sngiomeris! aide lei bite gh bee eee (63) Substitution of Eq. (62) in (61) gives * * ts P ° * p Pi W=31,100X,/dw —I lok, Re (Frin(ia)/Frin(io)} -HIelREM) ot oe} (64) =4],[p0X|@w —Iglo Re {Fmin(—iw) Fmin(iw)} +21 To RoXM spy (6i+ 0") Pest (65) since complex values of , occur in conjugate pairs. But Pi Pr (Pe tba)(@*+cPe) 9 itor PE +o* (Pippy —o?)?+0%(b, +3)” since Rep, 7 0) Seo (66) thus the contribution from non-minimum phase shift factors to the energy storage, namely 2TLoREM ipl (Pi +o"), sides eeses hee (67) is always positive. Physically, surplus non-minimum phase shift factors increase the group time delay for the transfer of energy to the energy dissipating resistance and so increase the energy storage (Kishi and Nakazawa, 1963). Consequently, W>4I,1p0X Co —IloR, Re {Fanto)/Fminteo)) (ae (68) equality applying when F(p) has no zeros in Rep >0. For the subsequent development, or for the situation in which R, is known only from measurements of Z, rather than analytically, another form of (68) may be obtained. At the same time this form indicates how the specialization to lumped-element networks might be relaxed. From Eq. (59) and the fact that F(f) is a real function of p —}3(OR,/Ow)/Ro=Im {F'(tw)/F(t@)}. eee eee eee eee eee. (69) The contribution to the energy in Eq. (61), which involves the dissipation function F(f), is pro- portional to Re {F’(tw)/F(im)}. Thus we require the real part of the function G(1w)= F’ (tw) /F (to) whose imaginary part is known in terms of R, from (69). For Re p>0, F(p) is a real analytic function. Consequently so is G(p) = Fp) FB) a eee ee ce eee (70) ENERGY STORAGE OF A PRESCRIBED IMPEDANCE Zad except when F(p)=0. Moreover, if F(p) has a zero of order M, at p=p,, G(p) has a simple pole of residue M,. Thus G(f) is analytic in Re p>0 except for simple poles of residue M, at zeros of F(p). These poles can occur in complex conjugate pairs anywhere in Re #>0 as a result of non- minimum phase shift factors in F(), or on the p=7w axis if Ry(¢w) vanishes. Contour integration may now be used to relate the real and imaginary parts of Glin). ie presence of poles of G(p) in Re p>0 necessitates a slightly different treatment from the usual one (Bode, 1945, Chap. XIV). We suppose G(#) regular at infinity with him “Gtw)="Geow ya ee eee ee ee (71) G@— + 00 Since G(f) is a real function of p, Go is real. G(p) —Ga I, p-iw sg where I’ is basically a large semi-circular contour extending —7o to 7p along the imaginary aXis and closed by an arc of radius ¢ in the half-plane Ref>0. The contour is indented into Re p >0 by small semi-circles of radius ¢ at /=7w and at any zeros, p=7w,, of F(p) on the imaginary / axis. Consider the contour integral Then by Cauchy’s theorem { ; ais dp= —2ni{sum of residues of (G(f) —Gao)/(p—iw) inside T}. .... (72) As poo the contribution from the large semi-circle vanishes, and as ¢->0 the small semi-circles contribute according to the residues s, of (G(p) —Go)/(p—iw) at the points p=iw, and at p=1. Equation (72) then ae P eee eee ea Gira Geen ae BEI (00) oven (73) where F denotes the as. principal value and 7,(w) are residues of G(p)/(f—iw) at poles of G(p) in Rep>0O. The imaginary part of Eq. (73) gives Re G(iw) =Goa— al “pat 25 INC, (G)) ey eee eee (74) After using (69) and evaluating the residues, this ae Ro(ik) [0% Mb Re {F' (tw) /F(t@)}= Gots tal" 2 hae ce eeegeep es (75) Thus from (61) Wa Tok ees RGR Gog af Rae Dy ee _. (76) Ro(28)(E—a@) » Py For a finite lumped-element system Gas vanishes and (76) reduces to (65) with Re {Fmin(—i@) Fmin(iw)} = = ale ne sie eine ae Sao rere ee eres (a) In distributed systems for which Go need not vanish, the term in Go has a simple physical interpretation. (—Gwo) is the time delay as woo and arises from a surplus exponential factor representing a constant time delay. Consequently Go is always non-positive. We conclude that W>41,0,aX, [do TT Ras p ie Rie oe. (78) Or Wet ijoxon—Il, Retin —10)Faav@)) 8... oon (79) 212 W. BE. SMITH equality holding when F=f min, the dissipation function having no non-minimum phase factors of any kind. Thus to a prescribed one-resistor network there corresponds a minimum energy storage uniquely determined by (78) from the given impedance function. If the network is a lumped-element network and R, is a known rational function, Eq. (79) can be used directly using standard algebraic methods for finding Fin rather than by evaluating the Hilbert transform in Eq. (78). Otherwise, in principle the Hilbert transform can be evaluated numerically from terminal measurements of Ay, but care is necessary in dealing with the principal value near singularities. Alternative forms for writing the transform (Bode, 1945; Morse and Feshbach, 1953) are then useful. For example Neg [PRA IBE ae Lop" {2m Reli/05—12 In Rul) gp R,(t8)(E—o) E—@ ly tof" a/d& (In [Ry(i8)/Rolieo)]) ay EF —w) The Hilbert transform form (78) for a minimum energy storage also occupies a central position in the subsequent theoretical development. The above analysis, though not restricted to lumped-element networks, is limited to cases for which the assumption that lim G(im) exists, is justified. The ordinary criteria for physical a@—-+ © realizability do not exclude, for example, the possibility of an unbounded infinite set of zeros of R, and hence of £(f) on the f=iw axis. In such a case lim G/(tw) does not exist. There is of @— + 0 course no difficulty with lumped-element systems and any distributed systems considered for extension of the results are assumed to be free of such complications. VII. The Minimum Energy Storage of a General Network In the previous section it was shown that for one-resistor networks there is a minimum energy storage, and an expression was derived for this minimum energy in terms of the terminal properties of the network as described by Z,(f). We now show that any network having the prescribed terminal behaviour irrespective of the number of resistors must store at least as much energy as this minimum for any particular f=1w. A general network will contain WN resistances R,, the dissipation in each being described by the N functions F,. The functions fF, are unknown in detail apart from the condition (43) on the total dissipation, 1.e. Rie) | Fea) |*& os. (81) k=1 Each F,(f) is a real causal function without poles for Re (f)>0, so that F,(p) is determined by | F(t) |? over the whole f=7w axis except for non-minimum phase shift all-pass factors. Now suppose we write RS? (ia) =| Fi, (é@) [2 oie os od Os (82) so that R$’ is the contribution to the total terminal resistance R, from dissipation in the 2‘ resistor of the network. Since R(iw) is always non-negative, there is associated with R‘” a minimum reactance impedance Zi io) = Re (od) 1X GO). 2 ee (83) There is also a minimum reactance impedance Zs") associated with the total resistance R,, and ENERGY STORAGE OF A PRESCRIBED IMPEDANCE 213 (min) The prescribed impedance Z,(#) can differ from Zj ~ only by its non-minimum reactance com- ponent, i.e. N ZG\ = GSO Zs ane Sohne ee kee her (86) k=1 where 2X(i@) is the non-minimum reactance function, if any, associated with Z). It has been seen in Section IV that the non-minimum reactance component of Z, presents no difficulties regarding energy storage, so we assume for simplicity in the current discussion that it has been subtracted out. That is, all of the impedances Z, Z{ are minimum reactance. From (44) the energy storage is N ( ; We ) Ha1oax” /@w—I,1o Re (FP) FulPllp~io} ees (87) Thus from (60) the energy storage of the multi-resistor network realization 1s the same as the energy : ; Pb ane ; 5 storage of N one-resistor networks having reactances Xj’ and dissipation transfer functions F,. We have already examined one-resistor networks in detail in the previous section. There is a minimum-energy storage W\*), given by equation (78) for each of these networks. Thus the equality sign holding if every F,(/) has no zeros for Re f>0. The magnitude of the sum in (87) will depend upon how the dissipation is distributed between the N resistors. We now consider another representation of Z, in which all dissipation takes place in a single resistor. From (78) the energy storage of this network exceeds (0) enh f 1p ae a us |” OR, (28) /0% W min=$1 lo0X,/Aw ree . RifE—a) eee (89) unless F(p) is minimum phase shift and equality applies. We now show that N SSW aes eee eee (90) k=1 so that from (88) the energy storage of any network realizing Z,() satisfies N Vie ae eee ere (91) | Because N RE) = ye ee ee (92) k=1 it is only necessary to show that “ _OR,(18)/08 S ple; i © ARw (i€) 8, Rio)? | au dé> X Ro’ (iw)F ; lay yn (Ge) oto] REE —a) = 1 HOF) RE —a) where Pe (G0) eee ee ee (94) and = ale R,(iw)= U RG (iw). oo. eee (95) Set Hy(®)=Rh(t)/Roliwm). «ec eee eee (96) Then y, denotes the fraction of the total power that is dissipated in the k" resistor. Lee. Oy Gy) ll eee eee eu (97) The y, are not defined by (96) when R)=0, which from (94), (95) implies R§ =0. y, may be defined as a limit in the vicinity of R>=0, but this is not necessary since the principal value reckoning of the integrals avoids such points. It is assumed, of course, that y,(w) 40, but 7,(@) can still 214 W. E. SMITH have zeros when R$” (iw) =0 with R(t) 40. Because y, is positive and indefinitely differentiable, its power expansion about a zero has an even power as the first non-vanishing term. This behaviour will be useful in dealing with the principal values of the integrals in (93) at »,—0. Now consider — pe © ( AR(iE)/OE ARG’ (iE) [0E 4am ne|| eee eee fae wesetaw asd sceet J (98) --9{— 2n{o)( In nelE)/08) e—— a heb tle awls wou ad's 60 5 0 eee (99) --9|" [ein (@ ) In [y,(&)/7(@ OTE Eel ar, Co. 1 ee (100) —Zpgleo) In {me (5)/Me(@)}y o 2Un,(e)(In (6) —In ,()) -9 E—o | is =|: 0 (6—@)? ae} from integrating by parts .. (101) oo 2(ng(o) In 74(&) —7,(@) In y,(e)) dz =—P i go Eel ee (102) = 0 since the integrand in (102) 1s always. <0 (see Appendix) .... 122.22 (103) The boundary terms from the integration by parts in (101) vanish because of the behaviour of , Near zeros, and because of the factor 1/7,(w) in the logarithm at =o. The equality sign in (103) only holds when the integrand in (102) is identically zero, which requires (see Appendix) %,(6) =He(@)=—constant. .....29- 62. (104) Equation (103) is equivalent to (93), so we have shown that (90) is generally true, the equality sign applying when the 7,(w) are constants. Thus, finally from (89), (90) and (91) it has been shown that for any specified minimum reactance impedance there exists a minimum energy storage W),, ie. Wewe, Maw eee (105) with Ww), hI Ip0Xq/00 —IyloR, 5 a te i Ries a =47, [0X ,/0m—Inlo Re{F minl 10) Pint) Sooo (107) where Fmin(t@) is the minimum-phase shift function satisfying F(—10) F (tw) = R(t). Further, this minimum energy storage corresponds at all frequencies p=7w to the energy storage of a minimum phase-shift Darlington synthesis of the impedance. Any non-minimum reactance component of the impedance Z,(f) can now be replaced in (106), (107) making them valid for a general impedance. ES eee (106) VIII. Realization of the Minimum Energy Storage On general mathematical grounds the minimum energy storage was shown to correspond to that of a network with one-resistor in which the transfer function F(p) is minimum phase shift (i.e., a minimum phase shift Darlington synthesis of Z)(p)). It is well known that in conventional Darlington synthesis using reciprocal networks (Balabanian, 1958) minimum phase shift synthesis is not always possible, extra non-minimum phase shift factors in F(p) being required to effect a synthesis. However, Hazony (1961) has shown that by using gyrators it is possible to carry out Darlington synthesis without surplus factors, so that minimum phase shift Darlington synthesis is possible. Thus the minimum energy storage for a lumped-element network corresponds to a realizable network. Thus the problem of a minimum energy synthesis of an impedance Z,() is ENERGY STORAGE OF A PRESCRIBED IMPEDANCE 215 at once both posed and solved. Minimum energy synthesis will normally require non-reciprocal elements. It will certainly require non-reciprocal elements if for some f=1 IT lig: XD AY es A mache on ts as noes nent (108) since from (15) I,Jo | X,/2w| is the lower bound on the energy storage of a reciprocal network. _ This occurs in the simple example to be considered in the next section. IX. A Simple Example A simple example will illustrate a number of points without the complexities of elaborate realizations. Take Z,(/)=1-+1/(£+1), and suppose a unit excitation current. By following the introductory steps to classical impedance synthesis the realization of Fig. 1 (a) is obtained. However, Z,(p) corresponds to an RC network function (Balabanian, 1958), so we know that the minimum energy storage for reciprocal networks is (Eq. (14)) 1a Poe Gn Leet (OLS Ls NOW tire one Sareea (109) corresponding to Fig. 1 (a). Figure 1 (0) is an alternative synthesis with the same energy storage N]- (c) Fic. 1—Realizations of Z,(p)=1+1/(1+)). Choosing mesh currents J, and I, in Fig. 1 (a) and J, and Jz in Fig. 1 (0) gives mesh impedance matrices a 2 Th tein oane eae tae! (111) 2 44+4/p The two networks store the same energy and we see they are connected by a Cauer equivalence transformation (7) with a 0 iG | ee ee eee (112) 0 —2 / A simple example of a reciprocal network realization storing more energy than the minimum for reciprocal network is shown in Fig. 1 (c). This network is degenerate in the sense that the structure indicates two poles of Z,(f), but the choice of component values leads to only one in Z,(p}. Such superfluous pole or zero behaviour is a characteristic of non-minimum energy reciprocal networks. This particular network stores three times the energy of the networks of Fig. 1 (a), 1 (0). Z (p) may also be realized by a reciprocal non-minimum phase shift Darlington synthesis (Fig. 2 (a2)), for which F(p)=(./2—P)[(L 4D). eee cee cece eee eee (113) 216 W. E. SMITH It cannot be realized by a minimum phase shift synthesis using reciprocal elements alone. The energy storage of this realization is found from Eq. (60) to be — W=3(8 424/202)" | 2.0... (114) — (3424/9) | X20 | ooh (115) which is (3-+2,/2) times that of the minimum-energy storing reciprocal networks. It must of course exceed the minimum for reciprocal networks because there is magnetic as well as electric energy storage. Fic. 2—Darlington reciprocal network synthesis of Z,(P) =1+1/(1+). We now consider what is the minimum possible energy storage for any realization of Z,(p). This may be evaluated either by (106) or more conveniently by (107). The minimum phase shift — F(p) for this impedance is Frin(f)=(4/2+0)/0-+e) .... (116) The non-minimum phase shift function (113) differs from this by the all pass _ factor (4/2—f)|(4/2+p). The minimum possible energy storage is then F+V=4(8—24/2)/(1 +o?) =6—24/2) | X20) ) aaa (117) Thus the minimum energy is only (S==2472) -~0-17 of the minimum reciprocal network energy storage. We note also that (115) exceeds (117) by 94/2/(1+-o*)\—2Ry {4/2 (e242)... (118) This excess is the non-minimum phase shift contribution (Eq. (65)) from the zero of F(p) at b=1/2. All that remains is to show how to achieve a synthesis with this minimum energy. Hazony (1961) has considered examples of non-reciprocal Darlington synthesis without surplus factors. His methods give the syntheses shown in Fig. 3 (a), (0). — — 42 42 (a) (b) Fic. 3—Non-reciprocal Darlington syntheses of Zp) =1+1/(1+P). These syntheses are independent of the sign of the gyrator coupling. One sign, as in Fig. 3 with Carlin’s convention (Carlin, 1955), gives minimum phase shift networks corresponding to the F(p) of Eq. (116), while the other gives F(p) corresponding to (113). Notice also that both networks in Fig. 3 (with appropriate gyrator coupling signs) store the same energy and represent the same impedance, but in one it is entirely electric and in the other it is entirely magnetic. (This behaviour is peculiar to non-reciprocal networks (Smith, 1967).) ENERGY STORAGE OF A PRESCRIBED IMPEDANCE 217 To illustrate the use of Vratsanos’ theorem in evaluating the energy storage by this impedance, ‘we must suppose Z,(#) is given as a function of the magnitudes of all resistors in the network and that the network is composed of reciprocal elements. For example, take the case where there are two resistors and PR, 2 Lol PR) = Sms ee eee 119 Oe) a (119) Then Z)(p,R,)=1+1/(1+f) when R,=1 and R,=1. From (52) : Fi(p) =R,(0Z,/OR,) R, R= P2/(LAP)2 oe ee (120) an 7A Gs) eed ce) a rere (121) The energy storage can then be evaluated to obtain eae oY (122) which is the same as for the network of Fig. 1 (c). X. Summary and Discussion The average energy storage of a sinusoidally excited, general linear, passive network has been seen to be not determined by terminal behaviour alone. That is, equivalent circuits in the usual terminology do not store the same energy for the same excitation. However, the class of networks related by Cauer’s equivalence transformation do. The energy storage is uniquely determined by the terminal behaviour whenever the system dissipates no energy, is an RL or RC network, or when the dependence of the terminal behaviour on the individual dissipative processes is known. For reciprocal element networks a simple lower bound exists for the energy storage at each frequency. This bound is attained at all frequencies by RL or RC networks. A general expression for the energy storage has been found and used to show that for any linear, passive network there is a minimum possible energy storage corresponding to a prescribed impedance. Further, this bound is attainable at all frequencies as a minimum energy synthesis. The minimum energy synthesis is a minimum phase-shift Darlington synthesis, and normally non-reciprocal elements (gyrators) are required for its realization. Only sinusoidal excitation of the impedance has been considered in detail. If we consider excitation represented by a Fourier integral, Parseval’s formula can be used to find the time integral of the instantaneous stored energy since the storage in every element is a quadratic function of the voltage or current. The time integral of the energy storage is the integral over all frequencies of the energy storage associated with the individual Fourier components of the excitation. Conse- quently the network storing minimum energy (in the sense of an integration over time) is the minimum energy synthesis of the impedance. Instantaneous energy storage as a function of time would need to be approached by energy conservation arguments analogous to Section IV, but involving the time-domain behaviour of the dissipation functions. The methods used in the development are not intrinsically restricted to lumped-element systems, so that with perhaps some qualifications the results should extend to distributed systems with non-rational Z,(). Also, the results are not restricted to electrical impedances, for example, the same arguments apply for an acoustic impedance. An extension to multi-port systems may also be possible. That non-reciprocal elements may sometimes be necessary for the general case to attain the minimum energy can be expected intuitively from relationships between group time-delay and energy storage (Kishi and Nakazawa, 1963). Carlin (1967) considers time-delays in a matched loss-free two-port and shows that negative group time delays are possible, but only in non-reciprocal systems. There are still some further questions of interest. Is there a synthesis of a general RLC ; . + |X ; network which attains the reciprocal network minimum energy bound $J,/ |—*| at all frequencies ? 218 We. SMITE This is easily shown to be impossible in general, by the counter example of a unit inductor in series with a parallel combination of a unit resistor and unit capacitor. Z)=(p?+-+41)/(p+1). This network is a minimum energy network, and for unit current stores a non-zero amount of energy at w=0. But 4] X,/w|=0 at w=0, which is less than the minimum possible energy. Thus the + |X, 0 . ° . . bound 4$1oLo a for reciprocal networks is not a close one and the absolute minimum can exceed it. Perhaps there is a better bound for the energy storage in reciprocal networks. If so, is it attainable at all frequencies by some realization ? That is, is there a minimum energy reciprocal element synthesis in the same way as there is an overall minimum energy synthesis? Classical methods of synthesis have stressed the number or types of elements required for synthesis. We could = whether Brune synthesis, for example, occupies a special place in the energy storage hierarchy. XI. References Tonninc, A., 1960. Energy Density in Continuous Electromagnetic Media. JRE Tvrans., AP-8, 428. BALABANIAN, N., 1958. Network Synthesis. Prentice- Vratsanos, J., 1957. Zur Berechnung der Strom- Hall, Englewood Cliffs, N.J. verteilung in einem linearen Netzwerk. Archiv. Bove, H. W., 1945. Network Analysis and Feedback dev elektrischen Ubertragung, 11, 76. Amplifier Design. Van Nostrand, New York. CaRLIN, H. J., 1955. Synthesis of Nonreciprocal Networks. Proc. Symposium on Modern Network Synthesis, 5, 11-44. Polytechnic Institute of XII. Appendix Brooklyn, New York. CarLIN, H. J., 1967. Network Theory without Circuit The following inequality is proved : Elements. Proc. IEEE, 55, 482. N CauER, W., 1958. Synthesis of Linear Communication If f= = (p; ng;—p; In p;) L(A L) Networks, 1, 2. McGraw-Hill, New York. pa GouBau, G., 1961. Electromagnetic Waveguides and N Cavities. Sec. 44, eqn. 44.7. Pergamon, New ‘ PoNe : : with o o,=1) oor eee (A2) Gross, B., AND BraGa, E. P., 1961. Singularities of Linear System Functions. Appendix 2. Elsevier, id Amsterdam. and De G,= 1), 1g Oe ee (A3) Hazony, D., 1961. Two Extensions of the Darlington i=1 Synthesis Procedure. [RE Trans., CT-8, 284. then fZ0 5. ee (A4) Kisu1, G., AND NAKAzAWA, K., 1963. Relations between Reactive Energy and Group Delay in the equality sign implying Lumped-Constant Networks. IEEE Trans., 0,=q; t=1, N CT-10, 67. : Le é Maa, D. Y., 1943. A General Reactance Theorem for Write f as Electrical, Mechanical and Acoustical Systems. N Proc. IRE, 31, 365. f= p,lin feta .. (A6) i=1 MoNnTGOMERY,C.: ‘G:, DickEe; R. H., AND PURCELL, db; b; U 1 E. M., 1948. Principles of Microwave Circuits. Bee OT 2 CG a en an which is equivalent to (A1) by virtu of (A2) Morse, P. M., AND FESHBACH, H., 1953. Methods of Theoretical Physics, 1, 370-373. McGraw-Hill, and (A3). “ Neve one. Now Inx+1—%*x <0 for all x>0 except *=1 PANNENBORG, A. E., 1952. On the Scattering Matrix A of Symmetrical Waveguide Junctions. Philips when In #+1—*x=0. Consequently, from (A6) Res. Repts., 7, 181. f <0 unless all £;=q;, in which case f=0. SmitH, W. E., 1965. Energy and Dispersion in Electro- magnetic Systems. Aust. J. Phys., 18, 287. (The author is indebted to an unknown Smitu, W. E., 1967. Electric- and Magnetic-Energy : ‘ Sia 3 Storage in Passive Nonreciprocal Networks. American referee for suggesting this simplified Electronics Letters, 3, 389. proof.) (Received 4 June 1969) os INDEX Page A Abstract of Proceedings, 1967 - 89 Annual Report, 3lst March, 1968 : 87 Annual Report of New England Branch, "1967. 95 Astronomy 109, 119, 157 Auld, Bruce A.—The Distribution of Eupatorium adenophorum ponent on the Far North Coast of N.S.W. 159 B Balance Sheet ‘ ei - od wes! Bambrick, Susan —The First Commonwealth Statistician : Sir George Knibbs 28 BZ Barrier Ranges, N.S.W., Stratigraphy and Structure of the North-east Part of the, by Cy KR Ward, C.. N. es and N. F. Taylor 57 Blue Mountains, N. S.W.—Triassic | Stratigraphy, by R. H. Goodwin 137 Botany ee ess) Brown, R. D. —Where Are the Electrons ? " Liver- sidge Research Lecture, 1968 73 Burman, S.—A Solar Charge and the Perihelion Motion of Mercury 157 C Chemistry : vs 163 Chemicals in Food. "Presidential PRaueee 1970, by J. W. G. Neuhaus 163 Citations 98 Clarke Medal for 1968 : 98 Coal in the Volcanic Necks near Sydney, N. 2. W., The Occurrence and Significance of Triassic, by LL. 14, Hamilton, KR. sasish amd. Grr EL, Taylor 169 Coals Containing Marcasite Plant Petrifactions, Yarrunga Creek, Sydney Basin, N.S.W., Note on, by H. W. Read and A. C. Cook 197 Conodonts from the Lick Hole Limestone, Southern N.S.W., Lower Devonian, by P. G. Flood .. 5 Cook, A. C., see H. W. Read ae. ee Coolac-Goobarragandra Ultramafic Belt, N.S.W., The, by H. G. Golding 173 Council : Annual Report, ist March, 1968 .. 4 Ou Balance Sheet >-.. s% ol D Distribution of Eupatorium adenophorum Spreng. on the Far North Coast of N.S.W., The, by Bruce A. Auld .. 159 Dulhunty, J. A., and Eadie, J.—Geology of the Talbragar Fossil Fish Bed Area ee 1 Page E Eadie, J., see J. A. Dulhunty i Edgeworth David Medal, 1967 98 Electrons ?, Where are the. Liversidge Memorial Lecture, 1968, by R. D. Brown ; 73 Energy Storage of a Prescribed Impedance, The, by W. E. Smith ys 203 Esdaile, E. E.—Obituary er ee eka Eupatorium adenophorum Spreng. on the Far North Coast of New South Wales, The Dis- tribution of, by Bruce A. Auld 159 in First Commonwealth Statistician: Sir George Knibbs, The, by Susan Bambrick 127 Flood, P. G. Lower Devonian Conodonts from the Lick Hole Limestone, Southern N.S.W. 5 Florey, Lord Howard W.—Obituary un 96 Food, Chemicals in. Presidential Address, 1970; by J. W. G. Neuhaus 163 Fossil Fish Bed Area, Geology of. the, by ie A. Dulhunty and J. Eadie ; li Fundamental ee Meson Field Potential in, Dy, Aaadie IK1GEz, , sigs 5s os 20k G Geology 1,5; 11, 2). 41,508 130 149; 169) 113,189; 197 Geology of the Talbragar Fossil Fish Bed Area, by J. A. Dulhunty and J. Eadie 1 Geology, Section of os .. 94 Golding, H. G.—The Coolac-Goobarragandra Ultramafic Belt, N.S.W. ss me weiss Goodwin, R. H. iassic Stratigraphy—Blue Mountains, N.S.W. 137 Granitic Development and Emplacement in the Tumbarumba-Geehi District, N.S.W. I. Ihe Poliated Granites, by B. B. Guy ll Il. The Massive Granites, by B. B. Guy 149 Guy, Bb. B.; Granitic Development and Emplacement in the Tumbarumba-Geehi District, N.S.W. ~ I. The Foliated Granites 11 II. The Massive Granites 149 H Hails, J. R.—The Nature and Occurrence of Heavy Minerals in Three Coastal Areas of N.S.W... 21 Hamilton, L. H.—The Occurrence and Significance of Triassic Coal in the Volcanic Necks near sydney, N.S. W. : 169 Heavy Minerals in the Three Coastal Areas of N.S.W., The Nature and Occurrence of, By jes Hails sie a ual Helby, Kk., see.L., i. Hamilton 169 INDEX Page K Keane, A.—A Problem in Mine Ventilation. Presidential Address, 1969 Bis s0 1 283 Kinematical Derivation of Lorentz “Trans- formations, A Note on a, by A. H. Klotz 123 Klotz. A. A. A Note on a Kinematical Derivation of Lorentz Transformations 123 Lorentz Transformations and Invariance of Maxwell’s Equations .. 125 Meson Field Potential in Fundamental Theory 201 Knibbs, Sir George, The First Commonwealth Statistician, by Susan Bambrick ye a7 L Lick Hole Limestone, Southern N.S.W., Lower Devonian Conodonts from the, by P. G. Flood a 5 Lindsay, John F. —Stratigraphy and Structure of the Palaeozoic Sediments of the Lower Macleay Region, North-eastern N.S.W. we atl Liversidge Research Lecture, 1968. Where Are the Electrons ?; by RK: D: Brown Set gah Lorentz ‘Transformations and Invariance of Maxwell’s Equations, by A. H. Klotz.. 125 Lower Devonian Conodonts from the Lick Hole Limestone, Southern N:S:W., by -P. G. Flood 5 M Manchester, E. G. H.—Obituary 96 Marcasite Plant Petrifactions, Yarrunga Creek, Sydney Basin, N.S.W., Note on Coals Con- taining, by H. W. Read and A. C. Cook as Mathematics So, 123) 125. 27, 20k 2 Maxwell’s Equations, Lorentz Transformations and Invariance ot, by A. EL “Kiotz 125 Medallists, 1967-1968 t8 98 Members of society, Istapril; 1969 : 101 Mercury, A Solar Charge and the Perihelion Motion of, by R. Burman ~. 157 Meson Field Potential in Fundamental Theory, by Aj Hy Kilotz: oe 201 Mine Ventilation, A Problem in. Presidential Address, 1969, by _A. Keane .. 83 Morrison, F. R.—Obituary 96 Murray, P. D. F.—Obituary 98 N Nature and Occurrence of Heavy Minerals in threes Coastal “Areas of INeS3W.. hes by, JP Kk. Hails ep 21 Neuhaus, J. W. G.—Chemicals in ‘Food. Presi- dential Address, 1970 , . 163 Note on a Kinematical Derivation of Lorentz Transformations, A, by A. H. Klotz. see 1483 Note on Coals Containing Marcasite Plant Petri- factions, Yarrunga Creek, Sydney Basin, New South Wales, Bios H. W. Read and A. C. Cook : . a ay Ge Page O Obituary ; : 96, 108 Occultations Observed at “Sydney Observatory during 1967-1968, by K. P. Sims 119 Occurrence and Significance of Triassic Coal in the Volcanic Necks near Sydney,) he; |by:i. Hi. Hamilton, R. Helby and G. H. Taylor 169 Officers for 1968-1969 Back of Title Page Ollé Prize 99 Pp Palaeozoic Sediments of the Lower Macleay Region, North-eastern N.S.W., Stratigraphy and Structure of the, by John F. Lindsay ~ Al Pels, S.—Radio-Carbon Dating of Ancestral River Sediments of the Riverine Plain of South- eastern Australia and Their Interpretation.. 189 Petrifactions, Yarrunga Creek, Sydney Basin, New South Wales, Note on Coals Containing Marcasite Plant, by H. W. Read and A. C. Cook : 197 Planets at Sydney Observatory during 1967 and 1968, Precise Observations of Minor, by W. H. Robertson 5 i 109 Precise Observations of Minor Planets at Sydney Observatory during 1967 and 1968, me W.. EL. Robertson : .. Log Presidential Address : 1969 A Problem in Mine Ventilation, by As, Keane 83 1970. Chemicals in Food, by Te. Wl G. Neuhaus 163 Problem in Mine Ventilation, A Presidential Address, 1969, by A “Keane = i WROEe Proceedings, Abstract of oe 89 R Radio-Carbon, Dating of Ancestral River Sediments of the Riverine Plain of South-eastern Australia and Their Interpretation, by S. Pels 189 Read, H. W., and A. C. Cook—Note on Coals Containing Marcasite Plant Petrifactions, Yarrunga Creek, Sydney Basin, N.S.W. 197% Riverine Plain of South-Eastern Australia, Radio- Carbon Dating of Ancestral River Sediments of the, and Their Interpretation, by S. Pels.. 189 Robertson, W. H.—Precise Observations of Minor Planets at Sydney ea ies pare 1967 and 1968 ; 109 S) Sediments of the Riverine Plain of South-Eastern Australia and Their Interpretation, Radio- Carbon Dating of Ancestral River, by S. Pels 189 Sims, K. P.—Occultations Observed at Sydney Observatory during 1967-1968 ee 119 Smith, W. E —The Energy eae ofa Prescribed Impedance : 203 Society’s Medal for 1967 aie 99 Solar Charge and the Perihelion Motion of Mercury, by R. Burman 157 re INDEX Page Stratigraphy and Structure of the North-east Part of the Barrier Ranges, N.S.W., By C. R. Ward, C. N. Wright-Smith and N. ‘taylor - .. 57 Stratigraphy and Structure of the Palaeozoic Sediments of the Lower Macleay Region, North-eastern N.S.W., Py ia F. cau 4] Sydney Observatory : 109, 119 T Taylor, G. H., see L. H. Hamilton 7" .. 169 maylor, N. F., see C. R. Ward .. a yy Triassic Coal in the Volcanic Necks near “Sydney, The Occurrence and Significance of, by L. H. Hamilton, R. Helby and G. H. Taylor.. 169 Triassic Stratigraphy—Blue Mountains, N.S.W., by Robert H. Goodwin es ar -. 137 Tumbarumba-Geehi District, N.S.W., Granitic Development and Emplacement in the: I. The Foliated Granites, by B. B. Guy... I1 II. The Massive Granites, by B.B. Guy .. 149 Page U Ultramafic Belt, N.S W., The Coolac-Goobarra- gandra, by H. G. Golding... ag .. 173 W Ward, C. R., C. N. Wright-Smith and N. R. Taylor—Stratigraphy and Structure of the North-east Part of the Barrier Ranges, N.SsW. es: we 8 ce vO Where Are the Electrons ?. ‘Liversidge Research Lecture, 1968, by R. D. Brown ae te SKS Wright-Smith, C. N., see C. R. Ward .. os 0 00 Y Yarrunga Creek, Sydney Basin, New South Wales, Note on Coals Containing Marcasite Plant Petrifactions, by H. W. Read and A. C. Cook 197 AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. 71-79 ARUNDEL ST., GLEBE, SYDNEY, N.S.W., 2037 y \ { ar oe. ; a Pe | : ‘ : | - Royal Society of Nex ew South Wales "a OFFICERS FOR 1968-1969 os 1 { “i ve int Y f ar a 3 ate Pee ee ‘Patrons we | He Geeelcnwte: THE GOVERNOR-GENERAL OF THE CommonwEaLTH oF AUSTRALIA, ; “Tar Ricut HONOURABLE LORD CASEY, P.C.,.G.C.M.G., C.H., D.S.0., M.C., K.St.Je > ee s “His EXCELLENCY THE. GoveRNor OF NEw SouTH’ WALES, Pig ake eS Ve SIR RODEN CUTLER, Vc; K.C.M.G., C.B.E. : (ities te aS President sa he ay pee : oA BEANE me ave eee et pies | " Vice-Presidents : En FE. CONAGHAN, M.Sc. Brees A. H. LOW, php. ne” Gata te, ee pad a A. DAY, Ph.p. (Cantab.) eit of ie ER VOISEY, p.sc. era eine wae WwW. ‘Lz FEVRE, DiS0 FRG) FAA EUS ee AN MY East Rr sna : Se Se Seite aes Mee ee Ee a Honorary Secretaries : Dyes 2 4 L. GRIFFITH, “BAS Merci oe EME: KRYSKO v. TRYST (adtrs. ), Beshis. Grad. Dip, cue oe tee Sie, Honorary Treasurer eae ce See omens Sieg Ba IPE is * W. G. NEUHAUS, M.Sc. See ae ee | ihe ou pee 2d Puech Librarian eee eS AUG POGGENDORFF, B.Sc.Agr., ae! | : < | Members ‘of Council | = ix BURG, AS.7.C.: Natsu Hi, Cee Wis ye PUTTOCK, B.Se. 5 ene “A.Inst.P, ot. C. CAMERON, M.A., B.Sc. Gast D.LC. _-. W. H. ROBERTSON, -B:sc. Re J. GRIFFIN, B.sc. . = W. E. SMITH, Ph.D, (N.S.W.), M.Sc. (ya), _T. E. KITAMURA, B.a., Bismagre 2 > *B.Se. ‘(oxon.), ae PB. POLLARD, Dip. APP. Chem, : eek Rk aL STANTON, Ph. Ds : : : : ‘NOTICE 2 The Royal eager of New South: ‘Wales originated in Se as hes = ' Philosophical Society of ~ “Australasia ” ; after an interval of inactivity it was resuscitated in 1850 under the name’of the OP ‘ Australian Philosophical Society. ’’, by which title it was known until 1856, when the name was ~ changed to ‘‘ Philosophical Society of New South Wales”. In 1866, by the sanction of Her Most Gracious Majesty Queen Victoria, the Society assumed its present title, and y was Cae lags by Act of Role wccsacinsre ‘of New, South Wales in 1881. Pp aa nae ee \ com | KA My a < on t SA 3 2 ~ w BE 2 é F Wer 2 fe KG 2 ¢ 7 fe ‘a S = \ Nr Z. 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