HARVARD UNIVERSITY E Ls LIBRARY OF THE Museum of Comparative Zoology = = a _ 0 JOURNAL AND PROCEEDINGS OF THE ROYAL SOCIETY OF NEW SOUTH WALES PARTS 1- IV VOL. 9| 1957 Edited by the Honorary Editorial Secretary PUBLISHED BY THE SOCIETY, SCIENCE HOUSE GLOUCESTER AND ESSEX STREETS, SYDNEY Issued as a complete volume April 23, 1958. KRayal Society of New South Wales OFFICERS FOR 1957-1958 Patrons: His EXcELLENCY THE GOVERNOR-GENERAL OF THE COMMONWEALTH OF AUSTRALIA Fretp-MarsHat Sir WILLIAM SLIM, G.oc.B., G.c.M.c., G.C.v.0., G.B.E., D.S.0., M.C. His ExcELLENCY THE GOVERNOR OF NEw SouTH WALES, LIEUTENANT-GENERAL SrR ERIC W. WOODWARD, £E.c.M.G., C.B., C.B.E., D.S.O. President : F. N. HANLON, B.sce. Vice-Presidents : Rey. T. N. BURKE-GAFFNEY, s.s. F. D. McCARTHY, pip.anthr. H. A. J. DONEGAN, msc. C. J. MAGEE, p.sc.agr. (Syd.), M.Sc. (Wis.). Hon. Secretaries : J. L. GRIFFITH, B.a., m.sc. | IDA A. BROWNE, p.sc. Hon. Treasurer: F. W. BOOKER, Ph.p. M.Sc. Members of Council: G. BOSSON, m.se. (Lond.). PHYLLIS M. ROUNTREEH, p.sc. (Melb.), G. W. K. CAVILL, m.sc. (Syd.), Ph.p. Dip.Bact. (Lond.). (Liverpool). G. TAYLOR, p.sc. B.E. (Min.), (Syd.), J. A. DULHUNTY, p.sc. B.A. (Cantab.), F.A.A. A. F. A. HARPER, m.sc. H. F. WHITWORTH, m.sc. D. P. MELLOR, D.sc. | H. W. WOOD, m.sc. W. H. G. POGGENDORFY, B.sc.agr. CONTENTS VOLUME 91 Part I* ANNUAL REPORT OF COUNCIL _ BALANCE SHEET REPORT OF SECTION OF GEOLOGY OBITUARY List oF MEMBERS AWARDS ART. I—PRESIDENTIAL ADDRESS. F'. D. McCarthy— Part I.—The Society’s Activities Part I1.—Theoretical Considerations of Australian Aboriginal Art ART. II.—OBSERVATIONS ON LATERITE AND OTHER IRONSTONE SOILS IN NORTH QUEENSLAND. JD. G. Simonett .. ART. ITI.—MAGNETIC PROPERTIES OF Rocks. HA. Narain and V. Bhaskara Rao ART. [LV.—OCCULTATIONS OBSERVED AT SYDNEY OBSERVATORY DURING 1956. K. P. Sims.. ART. V.—A POLARITY REVERSAL IN THE TERTIARY VOLCANICS OF THE KURRAJONG-BILPIN DISTRICT, WITH PETROLOGICAL NoTES. K. A. W. Crook. . : Part Ii; Art. VII.—A Stupy or RIVER TERRACES AND Som DEVELOPMENT ON THE NEPEAN River, N.S.W. P. H. Walker and O. A. Hawkins.. ART. VIII.—THE MINERALOGY OF THE COMMERCIAL DYKE CLAYS IN THE SYDNEY District, N.S.W. /F. C. Loughnan and H. G. Golding. . ART. [X.—MINOR PLANETS OBSERVED AT SYDNEY OBSERVATORY DURING 1956. W. H. Robertson ART. X.—ORDOVICIAN CORALS FROM NEW SouTH WALES. Dorothy Hill Vili evil 23 36 55 OL a | * Published October 23, 1957. + Published December 11, 1957. CONTENTS. Part III* Page ART. XI.—BOUNDARY STRESSES IN AN INFINITE HUB OF SPECIAL SHAPE. Alex. Reichel ae ane aft an fa 505 Ae THOS ArT. XII.—BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND Tumut POND IN THE SNOWY MOUNTAINS OF NEW SouTtH WALES. Germaine A. Joplin a bi He oe Se a ey 48) ART. XIII.—ON A FORMULA OF THE CONVOLUTION TYPE RELATED TO HANKEL TRANSFORMS. James L. Griffith Me he ae sls eee, ART. XIV.—THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. J. F. Lovering a ue Br He Gi ae Me Pea Part IV{ ART. XV.—CLARKE MEMORIAL LECTURE. FURTHER REMARKS ON SEDIMENTARY FORMATIONS IN N.S. WALES. A. H. Voisey oie ek es ART. XVI.—ADDENDUM TO My PApER ‘ON WEBER TRANSFORMS ”’. J. L. Griffith sie . ae a sa bite hein Heo ART. XVII.—THE ZEROS OF A CERTAIN FUNCTION INVOLVING BESSEL Functions. J. L. Griffith ti the as oe ae Bony ci (0) ART. XVIII.—TAPIOLITE AND THE TRI-RUTILE STRUCTURE. Florrie M. Quodling.. ae ay iv Ar ste ae ae af ASK ART. XIX.—THE MANILLA SYNCLINE AND ASSOCIATED FAULTS. A. H. Voisey 5 ae ate aie ae sud re ats er 413) ABSTRACT OF PROCEEDINGS .. ae ate bet: eis she at \ rox INDEX XXV TITLE PAGES FOR COMPLETE VOLUME FOR 1957. Vou. XCI, Parts I-IV. * Published February 27, 1958. ¢ Published April 23, 1958. AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. SEAMER AND ARUNDEL STS., GLEBE, SYDNEY “tN S PPT eee : ‘ : Bibs a Pou any f f pace j ts aT. feel wil | a > j PT OR Ey me dado | 5 te? | ; j ew { ; B & \ } NOV 2 5 1987} JOURNAL. AND PROCEEDINGS | , | ete? OF THE ROYAL SOCIETY OF NEW SOUTH WALES 1957 Edited by the Honorary Editorial Secretary PUBLISHED BY THE SOCIETY, » GLOUCESTER AND ESSEX STREETS” SYDNEY ; : ae ISSUED OOTOBER 23, 1957 SCIENCE HOUS Registered at the G.P.0., Sydney, N.S.W., for transmission by post as a periodical. Royal Society of Lew South Wales OFFICERS FOR 1957-1958 Patrons: His ExcELLENCY THE GOVERNOR-GENERAL OF THE COMMONWEALTH OF AUSTRALIA, FreLtp-MarsHat Sir WILLIAM SLIM, G.o.8., G.0.M.G., G.0.V.0., G.B.E., D.S8.0., M.O. His EXCELLENOY THE GOVERNOR OF NEw SouTH WALEs, LIZUTENANT-GENERAL E, W. WOODWARD, 6.B., 0.B.E., D.8.0. President: F. N. HANLON, B.sc. Vice-Presidents : Rev. T. N. BURKE-GAFFNEY, s.z. HD: MoCARTHY, Dip.Anthr. H. A. J. DONEGAN, m.sc. C. J. MAGEE, v.sc.agr. (Syd.), m.se. (W%8.). Hon. Secretaries : J. L. GRIFFITH, 8.4., M.Sc. | IDA A. BROWNE, p.sc. Hon. Treasurer ; : > F. W. BOOKER, Ph.D. M.8e. Members of Council: G. BOSSON, m.se. (Lond.). PHYLLIS M. ROUNTREE, D.se. (Melb.), G. W. K. CAVILL, m.sc. (Syd.), Ph.D. -|_ Dip.Bact, (Lond.). (Liverpool). - |G. TAYLOR, p.sc. B.B. (min.), (Syd.), J. A. DULHUNTY, p.se. B.A. (Cantab.), F.A.A. A. F. A. HARPER, .sc. H. F. WHITWORTH, m.sc. D. P. MELLOR, -D.sc. ~ | H.-W. WOOD, m.sc. : W. H. G, POGGENDORFF, B.Sc.Agr. : d JOURNAL AND PROCEEDINGS OF URE ROYAL SOCIETY OF NEW SOUTH WALES VOL. 9| 1957 Edited by the Honorary Editorial Secretary PUBLISHED BY THE SOCIETY, SCIENCE HOUSE GLOUCESTER AND ESSEX STREETS, SYDNEY NOV 25 1957 Rt | UaiveRSITY Royal Society of Nem South Wales REPORT OF THE COUNCIL FOR THE YEAR ENDED 3lst MARCH, 1957. PRESENTED AT THE ANNUAL AND GENERAL MONTHLY MEETING OF THE SOCIETY, 3rD APRIL, 1957, IN ACCORDANCE WITH RULE XXVI. At the end of the period under review the membership of the Society stood at 343. Twelve new members were elected during the year, but five members were lost by resignation and three names were removed from the list of members under Rule XVIII. In addition two persons were admitted as associates, these being the first in this category. By the death of Dr. Walter Fitzmaurice Burfitt on Ist June, 1956, the Society lost its oldest member. He had been a member since 1898, and was one of the greatest benefactors of the Society. His munificence and foresight made possible the establishment of the Walter Burfitt Prize awarded by this Society, a prize which is now Australia’s highest award for pure and applied research, It is with regret that we announce also the death of Robert Desider Louis Frederick on 20th August, 1956, a member since 1943. Nine monthly meetings were held. Details of these meetings will appear in the fourth part of Volume 90 of the Journal and Proceedings. ‘The members of Council wish to express their sincere thanks to the 19 speakers at the symposia and also to the members who read their papers at the December meeting. Annual Social Function.—Due to the incidence of the A.N.Z.A.A.S8. meeting and other meetings consequent, it was found impossible to choose a suitable date for the annual social function prior to the annual meeting. The retiring Council recommends to the incoming Council that this function should be held during the year. Awards.—The Walter Burfitt Prize, 1956, for outstanding publications in pure and applied science over the last six years was awarded to Professor J. C. Eecles, r.r.s., for his contributions to neurophysiology. The Clarke Medal for 1957 was awarded to Miss Irene Crespin for distinguished contributions in the field of geology. The Society’s Medal, 1956, which represents the Society’s appreciation of service not only to pure science but to the welfare of the Society itself, was awarded to Dr. W. R. Browne. The James Cook Medal for 1956 was awarded to Sir Ian Clunies Ross, in recognition of his outstanding contributions to the organization of science in Australia. The Archibald D. Olle Prize for the best original research paper by a member of the Society published in Volume 89 of the Journal and Proceedings was awarded to Dr. R. L. Stanton for his paper entitled ‘‘ Paleozoic Rocks in the Wiseman’s Creek-Burraga Area, N.S.W.”? This was the first occasion on which this award has been made. The Edgeworth David Medal. There was no award made for 1956. Liversidge Research Lectuwre.—The Liversidge Research Lecture, 1956. was delivered by Professor G. M. Badger on 12th July. The title of the lecture was ‘“‘ Recent Advances in the Chemistry of Aromatic Compounds ”’, and it attracted an excellent audience in the Department of Chemistry at the University of Sydney on a wet and unpleasant winter night. Finance.—The financial position of the Society is basically sound, although the audit of the current books of account showed a slight excess of expenditure over income (£57 2s, 5d.) for the year. The Society’s share of the profits from Science House during the year was £822 Is. 9d. The Society has again received a grant of £500 from the Government of New South Wales. The Government’s continued interest in the work of the Society is much appreciated. The Council has given serious consideration to the financial condition of the Society. Since the cost of administration has increased at a much higher rate than its income, several measures of economy have been taken, the effects of which should be apparent in the next balance sheet. Transfer of the Society’s office from the ground floor to the library on the first floor of Science House not only reduces our expenses but allows visiting members to become acquainted with the extent of the library. Rather than make a further increase in the annual subscription, Council decided to follow the lead of almost all other societies and to cease issuing the Jowrnal and Proceedings as a bound volume. Members, as well as libraries, will receive the quarterly parts immediately after publication. A ii ANNUAL REPORT. General.—The Council held eleven ordinary meetings. The attendance of members of Council was as follows: Mr. McCarthy, 10; Dr. Bosworth, 8 ; Dr. Ida Browne, 11 ; Dr. Lemberg, 8; Dr. Magee (on leave for two meetings), 6; Mr. Griffith, 11; Mr. Hanlon, 9; Mr. Donegan, 10 ; Rev. Burke-Gaffney, 11; Dr. Booker, 7; Dr. Dulhunty, 8; Dr. Dwyer, 4; Mr. Fletcher, 5; Mr. Harper, 10; Mr. Higgs, 2; Mr. Proud, 4; Prof. Taylor, 9; Mr. Wood, 10. The Society was represented on the Science House Management Committee by Mr. H. A. J. Donegan and Dr. R. C. L. Bosworth; Mr. F. R. Morrison and Mr. J. 8. Proud were substitute representatives. The President represented the Royal Society of New South Wales at the commemoration of the landing of Captain Cook at Kurnell and placed a wreath on the Banks Memorial Monument. The President also acted as the Society’s delegate at the meeting of A.N.Z.A.A.S. held at Dunedin, New Zealand, from 16th January, 1957, to 23rd January, 1957. The President, accompanied by the Honorary Secretary, waited on His Excellency the Governor of New South Wales on 11th June. A report was given to His Excellency on the activities of the Society during the past year. Dr. M. R. Lemberg, F.R.S., represented the Society at the opening of an exhibition of ‘““Tsotopes for Industry ’’ on 29th January, 1957. Section of Geology.—Mr. F. N. Hanlon was Chairman and Dr. L. J. Lawrence was Honorary Secretary. This Section met five times during the year on alternate months with the Geological Society of Australia (N.S.W. Division). The average attendance was 19. The Library.—The amount of £120 1s. 1ld. was expended on the purchase of periodicals, and an amount of £75 has been spent on binding journals in the library. Exchange of publications is maintained with 383 societies and institutions. For the twelve months ended 28th February the number of accessions to the library was 2,178. To conserve space in the library, the Council decided to sell some of the duplicate copies of periodicals and some of the out-of-date engineering and medical periodicals not currently received The amount received for these was £749 8s. 6d. The removal of the office to the first floor and the resignation of the Assistant Librarian, Mrs. E. P. Wilson, have caused some dislocation in the library services. This should soon be remedied with the appointment of a new Assistant Librarian. Among the institutions which made use of the library through the inter-library loan scheme were: C.8.I.R.O.—Library, Canberra, and Head Office, Melbourne ; Division of Plant Industry, Canberra ; Division of Industrial Chemistry, Melbourne ; Plant and Soils Laboratory, Brisbane ; Dairy Research Section, Highett, Victoria ; Coal Research Station ; McMaster Animal Health Laboratory ; Sheep Biology Laboratory ; Division of Food Preservation; Radio Research Board ; Division of Wool Textiles; National Standards Laboratory : Forestry Commission of New South Wales, Division of Wood Technology ; Department of Agriculture; Bureau of Mineral Resources ; Royal Society of New Zealand ; Cumberland County Council; Ministry of Civil Aviation; Collina Corporation; Electricity Commission; Snowy Mountains Hydro- Electric Authority ; Department of Public Health; Sydney Hospital; Royal North Shore Hospital ; Alfred Hospital, Melbourne ; Colonial Sugar Refining Co. Ltd.; Waite Agricultural Research Institute; South Australian Museum; Sydney Technical College; Wollongong Technical College; N.S.W. University of Technology ; University of Sydney; University of New England; University of Queensland; University of Melbourne; Australian National University. F. D. McCARTHY, President. 1956. £ 85 18 143 7,641 23,653 £31,540 8,960 14,835 6,800 517 20 1 £31,540 AA BALANCE SHEETS. THE ROYAL SOCIETY OF NEW SOUTH WALES. BALANCE SHEET AS AT 28th FEBRUARY, 1957. LIABILITIES. Australia and New Zealand Bank Ltd.—Overdraft Subscriptions Paid in Advance ae Life Members’ Subscription— Amount _ ‘carried forward ve Trust and Monograph Capital Funds (detailed below)— Clarke Memorial Walter Burfitt Prize Liversidge Bequest Monograph Capital Fund | Olle Bequest é ACCUMULATED FUNDS 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 .. Monograph Capital Fund General Purposes Debtors for Subscriptions .. Less Reserve for Bad Debts Science House—One-third Capital Cost Library—At Valuation ay Furniture and Office Equipment—At Cost, less Depreciation ee Pictures—At Cost, less Depreciation Lantern—At Cost, less Depreciation 1,876 1,143 686 3,956 heh d. £ s. a HS 205 19 6 2 3 8 1 7,740 15 23,528 ILI for) fe 2) =) On oe 502 19 1 oot £31,502 19 ili d. =H ele 0 iv BALANCE SHEETS. TRUST AND MONOGRAPH CAPITAL FUNDS. Walter Monograph Clarke Burfitt Liversidge Capital Olle Memorial. Prize. Bequest. Fund. Bequest. AY S.idie os s. d. 9516 151 0 0 154,14 5 61 16 10 956 10) 8 “771457 Less Expenditure ne 7419 6 11 0 3 Toe a0 ine! — — Balance at 28th February, 1957 £76 0 6 £143 14 2 —£13 3 9 £956 10 8 £77 14 1 ACCUMULATED FUNDS. if SSsd a 8. id: Balance at 29th February, 1956 a ae 235652717 16 Less— Increase in Reserve for Bad Debts ate eo AO Bad Debts Written Off ee Pe wa Zo Zea, Deficit for twelve months oe ie Soy OU een. 124, 16) 5 Balance at 28th February, 1957 Be sts £23,528 11 1 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, 1957, as disclosed thereby. We have satisfied ourselves that the Society’s Commonwealth Bonds and Inscribed Stock are properly held and registered. HORLEY & HORLEY, Per Conrad F. Horley, F.C.A. (Aust.), Prudential Building, Chartered Accountants (Aust.). 39 Martin Place, Sydney. 25th March, 1957. (Sgd.) H. A. J. DONEGAN, Honorary Treasurer. 1956. £ 23 To Annual Social Function (Balance 1956) BALANCE SHEETS. INCOME AND EXPENDITURE ACCOUNT. 1st March, 1956, to 28th February, 1957. Audit Cleaning Depreciation Electricity : Entertainment Expenses. . Insurance Library Purchases and Binding - Miscellaneous Postages and Telegrams Printing and Binding Journal— Vol. 88—Binding ae Vol. 89— Parts 2—4 Binding .. Vol. 90, Part 1 Printing—General Removal Expenses Rent—Science House } Management Repairs Reprints Salaries : Telephone .. Surplus for twelve months 882 By Membership Subscriptions £3,979 Proportion of Life Members’ Subscriptions He Subscriptions to Journal Government Subsidy Science House Management—Share of ‘Surplus Rentals Received—Reception Room Interest on General Investments Sale of Periodicals ew Library .. Sale of Back Numbers of Journals Deficit for twelve months SLIT 0 $56 15 129 15 Zea 6 Wm i) 1,330 112 131 61 9 103 1,039 31 liye £3,516 n ~_— ee NOAOMWWYIeE Ce OR: a> ° jon wee WOoOUIWdw)]S[ SS: _ 6 ABSTRACT OF THE PROCEEDINGS OF THE SECTION OF GEORG GH Chairman: F. N. Hanlon, B.se. Honorary Secretary: L. J. Lawrence, Ph.p., B.Se. Mvetings.—Five meetings were held during the year 1956, the average attendance being 19. March 16th : Annual meeting. Election of office-bearers: Chairman, Mr. F. N. Hanlon; Hon. Sec., Dr. L. J. Lawrence. -Address by Dr. T. G. Vallance, entitled ‘“* The Mineralogy of the Plagioclase Group”. Dr. Vallance illustrated by means of a series of graphs the methods of determining the various plagioclases and discussed the application of plagioclase mineralogy to the problems of depth and temperature of formation of the various igneous rocks. May 18th: Address by Dr. F. W. Booker, entitled ‘‘ The Relationship of Geological Surveys and the State Universities in the U.S.A.” Dr. Booker spoke of the close relationship that existed between geological surveys and State Universities in the U.S.A., and then showed a number of colour slides depicting university and survey buildings in America. July 29th: Address by Mr. F. C. Loughnan, entitled ‘*‘ The Place of Clay Mineralogy in the Study of Sedimentary Rocks”. Mr. Loughnan described the various modern techniques by which the clay minerals may be identified and then considered their mineralogy as an aid in the classification and correlation of argillic sediments. September 21st : In the absence of Dr. Phipps, who was to have addressed the Section, Dr. L. J. Lawrence delivered a short address on “‘ The Tin and Tungsten Deposits of the New England District’. Dr. Lawrence’s address was followed by a short address by Dr. L. E. Koch, who discussed various methods of assessing temperature of formation of tin and tungsten minerals. November 16th : Address by Mr. B. E. Balme, entitled ‘‘ Fossil Spores and Regional Stratigraphy’. Mr. Balme discussed the classification of fossil spores and illustrated how they are being used as a means of stratigraphic correlation in both terrestrial and marine sediments, with special application to petroleum exploration. Obituary WALTER FrrzMauRIcE BurrFirtr, who died on Ist June, 1956, at the age of eighty, after a long illness, had been a member of this Society for fifty-eight years. He was born at Dubbo, N.S.W., and educated at Riverview College and later at the University of Sydney, where he had a brilliant academic career, being awarded almost every prize and scholarship for which he was eligible to compete. He graduated Bachelor of Arts in 1894, with Honours in Mathematics and First-class Honours and the University Medal in Geology. His early interest in geology, fostered by his association with Professor David, for whom he had a profound admiration, was maintained throughout his life. Entering the Faculty of Medicine, he graduated M.B. and Ch.M. in 1900, with First-class Honours and the University Medal. While doing his medical course, he also graduated Bachelor of Science in 1898. After a year as Resident at Royal Prince Alfred Hospital, he entered private practice in Glebe, and shortly before World War I moved to Macquarie Street, to become one of Sydney’s leading surgeons. For many years an honorary surgeon at Lewisham Hospital, he was Senior Honorary Surgeon and Chairman of the Honorary Staff there at the time of his retirement in 1939. He was a member of the British Medical Association, and a Foundation Fellow of the Royal Australasian College of Surgeons. He maintained a lifelong interest in University affairs, and was Chairman of the Council of Sancta Sophia College within the University. In 1925 he made a gift of £1,000 to the University for the establishment of a scholarship to be awarded in the Faculty of Science for proficiency in Physics or Chemistry. This was but one manifestation of his practical concern for the careers of young research students. This Society has cause for holding him in grateful remembrance. He endowed it with a gift, later supplemented by his wife to £1,000, to found the Walter Burfitt Prize for published research work. Competition for this coveted award is very keen, and some of Australia’s foremost scientists have been the recipients of the prize. In addition to his zeal for the advancement of science, Dr. Burfitt was a man of wide human sympathy and benevolence. He was also characteristically modest and retiring, and never courted but rather shunned publicity. In 1932, at the meeting at which the Burfitt Prize was being presented, he was asked to speak, and was obviously embarrassed and almost apologetic. In 1908 he married Esmey Mann, and of their family of two sons and three daughters three have followed their father’s profession. Rospert DesipER Louis FREDERICK, who died on 20th August, 1956, was a member of the Society since 1943. Royal Society of New South Wales as at April 1, 1956 P Members who have contributed papers which have been published in the Society’s Journal. The numerals indicate the number of such contributions. t Life Members. Elected. 1944 1938 1935 1950 1941 1948 1948 1930 LOTS 1924 1934 1937 1951 1919 1951 1950 1950 1947 1933 1926 1937 1920 1948 1946 1933 1956 1951 1939 Pe? Pe? ie al Pa 2) 2 1E 7 P30 Pin2 Perl 9 1 P 26 Adamson, Colin Lachlan, 36 McLaren-street, North Sydney. tAlbert, Adrien, D.sc., Ph.p. Lond., B.Sc. Syd., Professor of Medical Chemistry, The Australian National University, Canberra, A.C.T. tAlbert, Michael Francois, ** Boomerang’, Billyard-avenue, Elizabeth Bay. Alexander, Albert Ernest, B.Sc., M.A., Ph.D., Professor of Chemistry, University of Sydney. tAlldis, Victor le Roy, Box 57, Orange, N.S.W. Anderson, Geoffrey William, B.sc., c/o Box 30, P.O., Chatswood. |; Andrews, Paul Burke, B.se., 5 Conway-avenue, Rose Bay. Aston, Ronald Leslie, B.se., B.E. Syd., M.Se., Ph.p. Cantab., Department of Civil Engineering and Surveying, University of Sydney. (President, 1948.) tAurousseau, Marcel, M.c., B.Se., 229 Woodland-street, Balgowlah, N.S.W. Bailey, Victor Albert, M.A., D.Phil, F.A.A., Professor of Experimental Physics, University of Sydney. Baker, Stanley Charles, m.sc., Department of Physics, Newcastle Technical College, Tighe’s Hill. Baldick, Kenric James, B.Sc., 19 Beaconsfield-parade, Lindfield. Banks, Maxwell Robert, B.se., Department of Geology, University of Tasmania, Hobart, Tasmania, tBardsley, John Ralph, 29 Walton-crescent, Abbotsford. Basden, Keith Spencer, B.sc., School of Mining and Applied Geology, N.S.W. University of Technology, Sydney. Baxter, John Philip, B.sc., Ph.p., F.A.A., Vice-Chancellor and Professor of Chemical Engineering, N.S.W. University of Technology, Sydney. Beck, Julia Mary (Mrs.), B.sc., 5 Hall-road, Isleworth, Middlesex, England. Beckmann, Peter, c/o Corrosion Research Unit, Department of Metallurgy, University of Cambridge, England. Bedwell, Arthur Johnson, *‘ Wongala’’, Boomerang-street, Turramurra. Bentivoglio, Sydney Ernest, B.se.agr., 42 Telegraph-road, Pymble. Birch, Arthur John, M.sc., D.Phil. Oxon., Professor of Organic Chemistry, University of Manchester. {Bishop, Eldred George, 264 Wolseley-road, Mosman. Blanks, Fred Roy, B.sc., 10 Glenwood-avenue, Coogee. Blaschke, Ernest Herbert, 6 Illistron Flats, 63 Carrabella-street, Kirribilli. Bolliger, Adolph, ph.p., Gordon Craig Urological Research Laboratory, Depart- ment of Surgery, University of Sydney. (President, 1945.) Bolt, Bruce Alan, M.sc., Department of Applied Mathematics, University of Sydney. Booker, Frederick William, M.sc., Ph.p., Government Geologist, c/o Geological Survey of N.S.W., Mines Department, Sydney. Booth, Brian Douglas, Ph.pD., B.Sc., 37 Highfield-road, Lindfield. tBooth, Edgar Harold, m.c., D.sc., 29 March-street, Bellevue Hill. (President, 1936.) Bosson, Geoffrey, m.sc. Lond., Professor of Mathematics, N.S.W. University of Technology, Sydney. Bosworth, Richard Charles Leslie, M.sc., D.Sc. Adel., Ph.D. Cantab., Associate Professor, School of Physical Chemistry, N.S.W. University of Technology, Sydney. (President, 1951.) Elected. 1946 1952 1919 1942 1935 1913 1952 1947 1940 1946 1952 1950 1955 1938 1944 1954 1933 1940 1952 1953 1935 1940 1940 1940 1948 1955 1940 1955 1948 1946 1945 1913 1933 1940 1909 1941 1955 1955 1921 1956 1954 1948 1940 1951 1952 1952 1952 1953 1 al ‘Psp Per P 23 2 2 Bae2 Pra P 2 P12 1 Peed Davi, Pl Peal P 3 ix Breyer, Bruno, M.pD., Ph.D., M.A., Department of Agricultural Chemistry, University of Sydney. Bridges, David Somerset, 19 Mt. Pleasant-avenue, Normanhurst. {tBriggs, George Henry, D.sSc., Ph.p., National Standards Laboratory of Australia, University Grounds, Sydney. Brown, Desmond J., m.sc. Syd., ph.p. Lond., b.1.c., Department of Medical Chemistry, Australian National University, Canberra, A.C.T. Browne, Ida Alison, D.sc., “‘ Mount Stewart’, 363 Edgecliff-road, Edgecliff. (President, 1953.) tBrowne, William Rowan, D.sc., F.A.A., ‘“* Mount Stewart ”’, 363 Edgecliff-road, Edgecliff. (President, 1932.) Bryant, Raymond Alfred Arthur, M.&., Companion R.Ae.S., School of Mechanical Engineering, N.S.W. University of Technology, Sydney. Buchanan, Gregory Stewart, B.Sc., School of Physical Chemistry, Sydney Technical College. Buckley, Lindsay Arthur, B.sc., 30 Wattle-street, Killara. Bullen, Keith Edward, M.A., Ph.D., Se.D., F.R.S., F.A.A., Professor of Applied Mathematics, University of Sydney, Sydney. {Burke-Gaffney, Rev. Thomas Noel, s.J., Director, Riverview College Observatory, Riverview, N.S.W. Burton, Gerald, B.sc. Syd., c/o Bureau of Mineral Resources, Canberra, A.C.T. Campbell, Ian Gavin Stuart, B.sc., c/o Wesley College, Prahran, Victoria. {Carey, Samuel Warren, D.sc., Professor of Geology, University of Tasmania, Hobart, Tas. Cavill, George William Kenneth, m.se. Syd., ph.p. Liverpool, School of Organic Chemistry, N.S.W. University of Technology, Sydney. tChaffer, Edric Keith, 27 Warrane-road, Roseville. Chalmers, Robert Oliver, Australian Museum, College-street, Sydney. Chambers, Maxwell Clark, B.se., 58 Spencer-road, Killara. Chapman, Dougan Wellesley, 3 Orinoco-street, Pymble. Christie, Thelma Isabel, B.se., Chemistry School, N.S.W. University of Tech- nology, Sydney. Churehward, John Gordon, B.Sc.Agr., Ph.D., 55 Belmont-road, Mosman. Cohen, Samuel Bernard, m.sc., 74 Boundary-street, Roseville. Cole, Edward Ritchie, B.sc., 7 Wolsten-avenue, Turramurra. Cole, Joyce Marie, B.sc., 7 Wolsten-avenue, Turramurra. Cole, Leslie Arthur, 21 Carlisle-street, Rose Bay. Coleman, Patrick Joseph, B.sc., Ph.p., Department of Geology, University of Sydney. Collett, Gordon, B.sc., 27 Rogers-avenue, Haberfield. Colville, Jean Norma (Mrs.), B.sc., 4 The Postern, Castlecrag. Cook, Cyril Lloyd, m.sc., Ph.pD., c/o Propulsion Research Laboratories, Box 1424H, G.P.O., Adelaide. Cook, Rodney Thomas, Buckley’s-road, Old Toongabbie, N.S.W. Coombs, Arthur Roylance, 14 Georges River-road, Croydon. {Coombs, F. A., Bannerman-crescent, Rosebery. Corbett, Robert Lorimer, c/o Intaglio Pty. Ltd., Box 3749, G.P.O., Sydney. Cortis-Jones, Beverly, m.sec., 62 William-street, Roseville. {Cotton, Leo Arthur, m.a., D.sc., Emeritus Professor, 113 Queen’s-parade East, Newport Beach. (President, 1929.) Craig, David Parker, ph.p., Department of Theoretical Chemistry, University College, London, W.C.1, England. Crawford, Edwin John, B.8., ‘‘ Lynwood ’’, Bungalow-avenue, Pymble. Crawford, Ian Andrew, 73 Wyadra-avenue, Manly. tCresswick, John Arthur, 101 Villiers-street, Rockdale. Croft, James Bernard, 2284 Old Canterbury-road, Summer Hill. ‘Crook, Keith Alan Waterhouse, B.sc., Geology Department, University of New England, Armidale, N.S.W. Cymerman-Craig, John, Ph.D., D.1.c., B.sc., Department of Organic Chemistry, University of Sydney. Dadour, Anthony, B.sc., 25 Elizabeth-street, Waterloo. Darvall, Anthony Roger, M.B., B.S., D.o., 119 Marsden-street, Parramatta. Davies, George Frederick, 57 Eastern-avenue, Kingsford. Day, Alan Arthur, B.sc. Syd., ph.p. Cantab., 13 Besborough-avenue, Bexley. Debus, Elaine Joan, 62 Tarrant’s-avenue, Eastwood. de Lepervanche, Beatrice Joy, 29 Collins-street, Belmore. x Elected. 1955 1955 1928 1947 1950 1937 1948 1951 1924 1955 1934 1945 1951 1950 1946 1934 1949 1940 1944 1908 1935 1949 1950 1909 1940 1940 1956 1933 1932 1950 1951 1944 1945 1952 1935 1939 1942 1947 1947 1948 1945 1953 1951 1947 1949 1948 P 15 P 62 iQ il P 2 1 Me P22 2 4 6 P 2 127i Denton, Leslie A., Bunarba-road, Miranda. Denton, Norma F. (Mrs.), Bunarba-road, Miranda. Donegan, Henry Arthur James, M.se., 18 Hillview-street, Sans Souci. Downes, Alan Marchant, B.se., c/o Sheep Biology Laboratory, C.S.I.R.O., Prospect, N.S.W. Drummond, Heather Rutherford, B.se., 2 Gerald-avenue, Roseville. Dulhunty, John Allan, p.se., Department of Geology, University of Sydney. (President, 1947.) Dunlop, Bruce Thomas, B.sSc., 77 Stanhope-road, Killara. Dunn, Thomas Melanby, B.sc., ¢/o William Ramsay & Ralph Forster Chemical Laboratory, University College, Gower-street, London, W.C.1., England. Dupain, George Zephirin, 15 Calvert-parade, Newport Beach. Durie, Ethel Beatrix, B.sc., M.B., Ch.m., Institute of Medical Research, Royal North Shore Hospital, St. Leonards. Dwyer, Francis P. J., D.Sc., Professor of Organic Chemistry, The University of Pennsylvania, U.S.A. Eade, Ronald Arthur, m.se. Syd., ph.p. Liverpool, School of Organic Chemistry, N.S.W. University of Technology, Sydney. Edgar, Joyee Enid (Mrs.), B.Sc., 16 Cooper-street, Cessnock. Edgell, Henry Stewart, ph.p. Stanford, c/o Iranian Oil Exploration & Pro- ducing Co., Masjid-i-Sulaiman, via Abadan, Iran. El Nashar, Beryl, B.sc., Ph.p., 23 Morris-street, Mayfield West, 2N, N.S.W. Elkin, Adolphus Peter, M.a., Ph.p., Emeritus Professor, 15 Norwood-avenue, Lindfield. (President, 1940.) Ellison, Dorothy Jean, m.se., 51 Tryon-road, Lindfield. Emmerton, Henry James, B.sc., 37 Wangoola-street, East Gordon. Erhart, John Charles, e/o ‘‘ Ciba’? Company, Basle, Switzerland. tEsdaile, Edward William, 42 Hunter-street, Sydney. Evans, Silvanus Gladstone, 6 Major-street, Coogee. Everingham, Richard, 97 Hopetoun-avenue, Vaucluse. Fallon, Joseph James, 1 Coolong-road, Vaucluse. {Fawsitt, Charles Edward, p.sc., ph.D., Emeritus Professor, 144 Darling Point- road, Edgecliff. (President, 1919.) Finch, Franklin Charles, B.sc. Fisher, Robert, B.sc., 3 Sackville-street, Maroubra. Fleischmann, Arnold Walter, 8/25 Guilfoyle-avenue, Double Bay. Fletcher, Harold Oswald, m.sc., The Australian Museum, College-street, Sydney. Forman, Kenn P., 52 Pitt-street, Sydney. Freeman, Hans Charles, m.sc., 43 Newcastle-street, Rose Bay. French, Oswald Raymond, 66 Nottinghill-road, Lidcombe. Friend, James Alan, m.sc. Syd., Ph.p. Cantab., Department of Chemistry. Uni- versity of Tasmania, Box 647c, Hobart, Tas. Furst, Hellmut Friedrich, B.p.s. Syd., p.mM.p. Hamburg, 158 Bellevue-road, Bellevue Hill. Garan, Teodar, c/o Chief Geologist, Warragamba Dam, N.S.W. Garretty, Michael Duhan, p.sc., ‘‘ Surry Lodge’’, Mitcham-road, Mitcham, Victoria. Gascoigne, Robert Mortimer, Ph.p. Liverpool, Department of Organic Chemistry, N.S.W. University of Technology, Sydney. xibson, Neville Allan, m.sc., Ph.p., 103 Bland-street, Ashfield. Gill, Naida Sugden, B.sc., Ph.p., 45 Neville-street, Marrickville. tGill, Stuart Frederic, 45 Neville-street, Marrickville. Glasson, Kenneth Roderick, B.sc., 70 Beecroft-road, Beecroft. Goddard, Roy Hamilton, Royal Exchange, Bridge-street, Sydney. Golding, Henry George, B.sc. Lond., m.sc. Syd., School of Mining Engineering and Applied Geology, N.S.W. University of Technology, Sydney. Goldstone, Charles Lillington, B.Agr.sc. N.Z., East Sydney Technical College, Darlinghurst. Goldsworthy, Neil Ernest, M.B., ch.m. Syd., ph.D., 118 Ryde-road, West Pymble. Gordon, William Fraser, B.Sc., 176 Avoca-street, Randwick. Gray, Charles Alexander Menzies, B.Sc., B.E., Professor of Engineering, Uni- versity of Malaya, Malaya. Elected. 1952 1952 1952 1946 1934 1949 1955 1940 1905 1936 1934 1948 1946 1954 1956 1951 1955 1919 1952 1945 6 1 Pb P 6 P~6 Pe 4 6 Pe 3 Poel 7 1 Pr 2 1 all 12 8} Xi Gray, Noel Mackintosh, B.sc. W.A., 6 Twenty-fourth-street, Warragamba Dam, N.S.W. Griffin, Russell John, B.sc., c/o Department of Mines, Sydney. Griffith, James Langford, B.A., M.se., School of Applied Mathematics, N.S.W. University of Technology, Sydney. Gutmann, Felix, ph.p., N.S.W. University of Technology, Sydney. Hall, Norman Frederick Blake, m.se., 154 Wharf-road, Longueville. Hampton, Edward John William, 1 Hunter-street, Waratah, N.S.W. Hancock, Harry Sheffield, B.sc., 491 New Canterbury-road, Dulwich Hill. Hanlon, Frederick Noel, B.sSc., 22 Grayling-road, Pymble. (President, 1957.) tHarker, George, D.Sc., 89 Homebush-road, Strathfield. Harper, Arthur Frederick Alan, m.se., National Standards Laboratory, Uni- versity Grounds, City-road, Chippendale. Harrington, Herbert Richard, 28 Bancroft-avenue, Roseville. Harris, Clive Melville, B.sc., School of Inorganic Chemistry, N.S.W. University of Technology, Sydney. Harrison, Ernest John Jasper, B.Sc., c/o N.S.W. Geological Survey, Department of Mines, Sydney. Hasan, Syed Manzurul, M.sc., F.G.s., c/o Bureau of Mineral Resources, P.O. Box 449, Darwin, N.T. Hawkins, Cedrie Arthur, B.Sc.Agr., 11 Mitchell-street, Ermington. Heard, George Douglas, B.sc., Queanbeyan Intermediate High School, Quean- beyan, N.S.W. Heath, Russel Alan, ‘‘ Heathcote ’’, 9 Potter-avenue, Earlwood. tHenriques, Frederick Lester, Billyard-avenue, Elizabeth Bay. Hewitt, John William, B.sc., 31 Weatherill-street, Narrabeen. Higgs, Alan Charles, c/o Colonial Sugar Refining Co. Ltd., Building Material Division, Chatsworth House, 1-7 Bent-street, Sydney. Hill, Dorothy, p.se. Qld., Ph.p. Cantab., F.A.A., Department of Geology, Uni- versity of Queensland, St. Lucia, Brisbane, Queensland. Hogarth, Julius William, B.se., 8 Jeanneret-avenue, Hunters Hill. Holm, Thomas John, 524 Wilson-street, Redfern. Holmes, Robert Francis, 15 Baden-street, Coogee. tHynes, Harold John, p.sc.Agr., M.sc., Assistant Director, Department of Agri- culture, Box 36, G.P.O., Sydney. Iredale, Thomas, D.Sc., Chemistry Department, University of Sydney. Jaeger, John Conrad, M.A., D.Sc., F.A.A., Geophysics Department, Australian National University, Canberra, A.C.T. Jamieson, Helen Campbell, 3 Hamilton-street, Coogee. Jenkins, Thomas Benjamin Huw, B.sc., Ph.p., c/o A.O.G. Corp., Ltd., 133 Pitt-street, Sydney. Joplin, Germaine Anne, B.A., Ph.D., D.Sc., Geophysics Department, Australian National University, Canberra, A.C.T. Jopling, Alan Victor, B.Se., B.E. Keane, Austin, Ph.p., School of Mathematics, N.S.W. University of Technology, Sydney. Kelly, Caroline Tennant (Mrs.), Dip.anth., ‘“‘ Avila”’, 17 Heydon-avenue, Warrawee. Kenny, Edward Joseph, Under Secretary, Department of Mines, Sydney . Kimble, Frank Oswald, 31 Corongac-street, Killara. Kimble, Jean Annie, B.sec., 383 Marrickville-road, Marrickville. {Kirchner, William John, B.sc., 18 Lyne-road, Cheltenham. Knight, Oscar Le Maistre, B.z., 10 Mildura-street, Killara. Koch, Leo E., pr.phil-Hrabil Cologne, c/o N.S.W. University of Technology, Sydney. Lambeth, Arthur James, B.sc., ‘‘ Naranje’’, Sweethaven-road, St. John’s Park, N.S.W. Lancaster, Kelvin John, .a., B.Sc., B.Sc.Econ., London School of Economical and Political Science, Houghton-street, Aldwych, W.C.2, England. xii Elected. 1955 P 3 P 56 Pil P 2 P 2 Pod P 2 P 4 Pp 2 Pa 1) Pa P14 Poa P 25 Lang, Thomas Arthur, m.c.£., Associate Commissioner, Snowy Mountains Hydro-Electrie Authority, Cooma, N.S.W. | Lawrence, Laurence James, Ph.p., School of Geology, N.S.W. University of Technology, Sydney. | Leach, Stephen Laurence, B.A., B.Sc., ¢/o Taubman’s Industries Ltd., Box 82a, P.O., North Sydney. Le Fevre, Raymond James Wood, D.sc., Ph.D., F.A.A., Professor of Chemistry, University of Sydney. Lemberg, Max Rudolph, D.pPhil., F.R.S., F.A.A., Assistant Director, Institute of Medical Research, Royal North Shore Hospital, St. Leonards. (President, 1955.) {Lions, Francis, B.sc., Ph.p., Department of Chemistry, University of Sydney. (President 1946-47.) Lions, Jean Elizabeth (Mrs.), B.sc., 160 Alt-street, Haberfield. Lloyd, James Charles, B.sc. Syd., N.S.W. Geological Survey, Department of Mines, Sydney. Lockwood, William Hutton, B.Sc., c/o Institute of Medical Research, The Royal North Shore Hospital, St. Leonards. ‘tLoney, Charles Augustus Luxton, National Mutual Building, 350 George-street, Sydney. Loughnan, Frederick Charles, B.sc., 11 Rosebridge-avenue, East Willoughby. Lovering, John Francis, m.se. Syd., ph.p. Calif. Inst. Tech., Department of Geophysics, Australian National University, Canberra, A.C.T. Low, Angus Henry, m.sc., School of Mathematics, N.S.W. University of Tech- nology, Sydney. tLuber, Daphne (Mrs.), B.sc., 98 Lang-road, Centennial Park. Luber, Leonard, 80 Queen-street, Woollahra. Lyons, Lawrence Ernest, B.A., M.Sc. Syd., Ph.p. Lond., Chemistry Department, University of Sydney, Sydney. Maccoll, Allan, M.se., Department of Chemistry, University College, Gower- street, London, W.C.1. McCarthy, Frederick David, Dip.anthr., Australian Museum, Sydney. (President 1956.) McCoy, William Kevin, c/o Mr. A. J. McCoy, 23 Victoria-road, Pennant Hills. McCullagh, Morris Behan, 23 Wallaroy-road, Edgecliff. McElroy, Clifford Turner, B.sc., ‘‘ Bithongabel’’, Bedford-road, Woodford, N.S.W. McGregor, Gordon Howard, 4 Maple-avenue, Pennant Hills. McInnes, Gordon Elliott, B.sc., Cranbrook School, Bellevue Hill. McKay, Maxwell Herbert, m.a., School of Mathematics, N.S.W. University of Technology, Sydney. McKenzie, Peter John, B.sc., 33 Harbour-street, Mosman. McKern, Howard Hamlet Gordon, Museum of Applied Arts and Sciences, Harris-street, Broadway. McMahon, Patrick Reginald, m.agr.sc. N.Z., ph.p. Leeds, Professor of Wool Technology, N.S.W. University of Technology, Sydney. McNamara, Barbara Joyce (Mrs.), M.B., B.S., 82 Millwood-avenue, Chatswood. McPhee, Stuart Duncan, 14 Lennon-street, Gordon. McPherson, John Charters, 14 Sarnar-road, Greenwich. Magee, Charles Joseph, p.sc.Agr. Syd., M.Sc. Wis., Chief Biologist, Department of Agriculture. (President 1952.) Males, Pamela Ann, 13 Gelding-street, Dulwich Hill. Mandl, Lothar Max, pipl.mg. Tech. Univ. of Vienna, Senior Technical Officer, C.S.LR. O. Mapstone, George E., m.sc., c/o S.A.T.M.A.R., P.O. Box 5083, Boksburg North, Transvaal, Union of South Africa. Marshall, Charles Edward, Ph.pD., D.sc., Professor of Geology, University of Sydney. Marsden, Joan Audrey, 203 West-street, Crows Nest. May, Albert, ph.p., M.A., 94 Birriga-road, Bellevue Hill. Maze, William Harold, M.Se., Deputy Principal, The University of Sydney. Meares, Harry John Devenish: Technical Librarian, Colonial Sugar Refining Co. Ltd., Box 483, G.P.O., Sydney. {Meldrum, Henry John, B.A., B.Sc., 98 Sydney-road, Fairlight. Mellor, David Paver, D.sc., Professor of Applied Chemistry, N.S.W. University of Technology, Sydney. (President, 1941.) Elected. 1950 1940 1951 1922 1941 1934 1948 1955 1944 1946 1915 1951 1950 1930 1943 1932 1945 1920 1947 1940 1951 1947 1950 1951 1920 1948 1956 1953 1938 1935 1946 1943 1919 1949 1921 1938 1927 1956 1918 1956 1945 1935 P 34 Bae ea 1B P 26 12) 8} P 82 iPad Ps Pp 2 1 al Peas xiii Millar, Lily Maud (Mrs.), 4 Waratah House, 43 Bayswater-road, King’s Cross. Millership, William, m.sc., 18 Courallie-avenue, Pymble. Minty, Edward James, B.Se., Cooyong-road, Terrey Hills, N.S.W. {Morrison, Frank Richard, Director, Museum of Apphed Arts and Sciences, Harris-street, Broadway, Sydney. (President 1950-51.) Morrissey, Matthew John, B.A., M.B., B.S., 46 Auburn-street, Parramatta. Mort, Francis George Arnot, 110 Green’s-road, Fivedock. Mosher, Kenneth George, B.Sc., c/o Joint Coal Board, 66 King-street, Sydney. Moss, Francis John, m.B., B.S. Melb., 15 Ormonde-road, Roseville Chase, N.S.W. Moye, Daniel George, B.sc., Chief Geologist, ¢/o Snowy Mountains Hydro- Electric Authority, Cooma, N.S.W. Mulholland, Charles St. John, B.sc., Assistant Under-Secretary, Department of Mines, Bridge-street, Sydney. tMurphy, Robert Kenneth, pDr.tng.chem., 68 Pindari-avenue, North Mosman. Murray, James Kenneth, B.Sc., 464 William-lane, Broken Hill, N.S.W. Murray. Patrick Desmond Fitzgerald, M.a., D.Sc., F.A.A., Professor of Zoology, University of Sydney. Naylor, George Francis King, M.a., M.Sc. Syd., Ph.p. Q’ld., Department of Psychology and Philosophy, University of Queensland, Brisbane. tNeuhaus, John William George, 32 Bolton-street, Guildford. Newman, Ivor Vickery, M.Sc., Ph.D., Department of Botany, University of Sydney. Noakes, Lyndon Charles, B.a., c/o Mineral Resources Bureau, Canberra, A.C.T. tNoble, Robert Jackson, M.sc., B.Sc.Agr., Ph.D., Under Secretary and Director, Department of Agriculture, Box 36, G.P.O., Sydney. (President, 1934.) Nordon, Peter, 60 Hampton Park, Redland, Bristol 6, England. Nyholm, Ronald Sydney, m.sc. Syd., Ph.p., D.Sc. Lond., Professor of Inorganic Chemistry, London University College, Gower-street, London, W.C.1, England. (President, 1954.) tO’Dea, Darly Robery, Box 14, P.O., Broadway. Old, Adrian Noel, B.sc.agr., 4 Springfield-avenue, Potts Point. Oxenford, Reginald Augustus, B.Sc., 10 Fry-street, Grafton, N.S.W. Packham, Gordon Howard, B.se., Department of Geology and Geophysics, University of Sydney. Penfold, Arthur Ramon, 50 Park-avenue, Roseville. (President, 1935.) Perry, Hubert Roy, B.sc., 74 Woodbine-street, Bowral. Petersen, George, 108 Northcote-street, Naremburn. Phillips, June Rosa Pitt, B.sc., Geology Department, University of Sydney. Phillips, Marie Elizabeth, B.sc., php.. Manchester, Soil Conservation Section, S.M.H.E.A., Cooma, 4 Morella-road, Clifton Gardens. Phillips, Orwell, 55 Darling Point-road, Edgecliff. Pinwill, Norman, B.A. Q’ld., The Scots College, Bellevue Hill. Plowman, Ronald Arthur, B.sc., Ph.p. Lond., Chemistry Department, University of Queensland, Brisbane. {Poate, Sir Hugh Raymond Guy, m.B., ch.m. Syd., 225 Macquarie-street, Sydney. Poggendorff, Walter Hans George, B.Sc.Agr., Chief, Division of Plant Industry, N.S.W. Department of Agriculture, Box 364, G.P.O., Sydney. tPowell, Charles Wilfrid Roberts, ‘‘ Wansfell ’’, Kirkoswald-avenue, Mosman. Powell, John Wallis, c/o Foster, Clark (Aust.) Ltd., 17 Thirlow-street, Redfern. Price, William Lindsay, B.£., B.Sc., School of Physics, Sydney Technical College, Sydney. Priddle, Raymond Arthur, B.E., 7 Rawson-crescent, Pymble. {Priestley, Henry, M.p., ch.m., B.Sc., 54 Fuller’s-road, Chatswood. (President, 1942-43.) Prokhovnik, Simon Jacques, B.A., B.Sc. Melb., School of Mathematics, N.S.W. University of Technology, Sydney. tProud, John Seymour, B.£., Finlay-road, Turramurra. {tQuodling, Florrie Mabel, B.sc., Department of Geology, University of Sydney. Xiv Elected. 1953 1922 1919 1947 1931 1947 1947 1939 1939 1940 1949 1951 1940 1948 1945 mw tm NH ro kg tor or or bo o me bo Rade, Janis, M.sc., 694 Broadway, Nedlands, Perth, W.A. Raggatt, Harold George, C.B.B., D.Sc., F.A.A., Secretary, Department of National Development, Acton, Canberra, A.C.T. {Ranclaud, Archibald Boscawen Boyd, B.sc., B.E.. 57 William-street, Sydney. Ray, Reginald John, *‘ Treetops’, Wyong-road, Berkeley Vale. Rayner, Jack Maxwell, B.sc., Deputy Director, Bureau of Mineral Resources, Geology and Geophysics, 485 Bourke-street, Melbourne, Vic. Reuter, Fritz Henry, ph.p. Berlin, Associate Professor of Food Technology, N.S.W. University of Technology, Sydney. Ritchie, Arthur Sinclair, Department of Mineralogy and Geology, Newcastle University College, Newcastle. Ritchie, Ernest, D.sc., Chemistry Department, University of Sydney, Sydney. Robbins, Elizabeth Marie (Mrs.), M.se., Waterloo-road, North Ryde. Robertson, Rutherford Ness, B.sc. Syd., Ph.p. Cantab., F.A.A., Senior Plant Physiologist, C.S8.1.R.O., c/o Botany Department, University of Sydney. Robertson, William Humphrey, B.sc., c/o Sydney Observatory, Sydney. Robinson, David Hugh, 39 Molton-road, Beecroft. Rosenbaum, Sidney, 23 Strickland-avenue, Lindfield. Rosenthal-Schneider, Ilse, ph.p., 48 Cambridge-avenue, Vaucluse. Rountree, Phyllis Margaret, D.sc. Melb., Dip.Bact. Lond., Royal Prince Alfred Hospital, Sydney. Sampson, Aileen (Mrs.), 9 Knox-avenue, Epping. {Scammell, Rupert Boswood, B.sc. Syd., 10 Buena Vista-avenue, Clifton Gardens. Searl, Robert Alexander, B.sc., Rio Australian Exploration P/L., 20 Queen’s- road, Melbourne. See, Graeme Thomas, B.sSc., School of Mining Engineering and Geology, N.S.W. University of Technology, Sydney. Selby, Edmond Jacob, Box 175p, G.P.O., Sydney. Sergeyeff, William Peter, 137 Prince’s-highway, St. Peters. tSharp, Kenneth Raeburn, B.sc., c/o S.M.H.E.A., Cooma, N.S.W. Sherrard, Kathleen Margaret (Mrs.), M.sc. Melb., 43 Robertson-road, Centennial Park. Simmons, Lewis Michael, B.sc., Ph.p. Lond., c/o Scots College, Victoria-road, Bellevue Hill. Simonett, David Stanley, M.se., Ph.p., Assistant Professor of Geography, University of Kansas, Lawrence, Kansas, U.S.A. Simpson, John Kenneth Moore, ‘‘ Browie ’’, Old Castle Hill-road, Castle Hill. Sims, Kenneth Patrick, B.sc., 18 Onyx-road, Artarmon. Slade, George Hermon, B.sc., ‘‘ Raiatea ’’, Oyama-avenue, Manly. Slade, Milton John, B.se., 10 Elizabeth-street, Raymond Terrace, N.S.W. Smith, Erie Brian Jeffcoat, D.Phil. Oxvon., 74 Webster-street, Nedlands, W.A. Smith-White, William Broderick, m.a. Cantab., B.Sc. Syd., Department of Mathematics, University of Sydney. |tSouthee, Ethelbert Ambrook, 0.B.E., M.A., B.Sc., B.Sc.Agr., Trelawney-street, Eastwood. Stanton, Richard Limon, ph.p., B.Sc., 42 Hopetoun-avenue, Mosman. Stapledon, David Hiley, B.sc., c/o Section of Geology, S.M.H.E.A., Cooma N.S.W. tStephen, Alfred Ernest, c/o Box 1158HH, G.P.O., Sydney. {Stephens, Frederick G. N., F.R.c.S., M.B., Ch.M., 135 Macquarie-street, Sydney. Stevens, Neville Cecil, ph.p., Department of Geology, University of Queensland, St. Lucia, Brisbane, Queensland. Stevens, Robert Dencil, B.sc., Bureau of Mineral Resources, Canberra, A.C.T~ ‘{Stone, Walter George, 26 Rosslyn-street, Bellevue Hill. Stuntz, John, B.sc., 511 Burwood-road, Belmore. tSullivan, Herbert Jay, ‘* Stonycroft ’’, 10 Redmyre-road, Strathfield. tSutherland, George Fife, a.R.c.sc. Lond., 47 Clanwilliam-street, Chatswood. \{Sutton, Harvey, 0.B.E., M.D., D.P.H. Melb., B.sc. Oxon., ‘‘ Lynton ’’, 27 Kent- road, Rose Bay. Swanson, Thomas Baikie, m.sc. Adel., c/o Technical Service Department, I.C.1.A.N.Z., Box 1911, G.P.O., Melbourne, Victoria. Swinbourne, Ellice Simmons, 1 Raglan-street, Manly. |Taylor, Griffith, D.sc., B.E. (Min.) Syd., B.A. Cantab., F.A.A., Emeritus-Professor, 28 Alan-avenue, Seaforth, N.S.W. (Previous membership, 1921-1928.) XV Elected. ° 1915 P 3 |tTaylor, Brigadier Harold B., M.c., D.sc., 12 Wood-street, Manly. 1955 Thew, Raymond Farly, 88 Braeside-street, Wahroonga. 1944 Thomas, Andrew David, Squadron Leader, R.A.A.F., M.sc., 45 Greengate-road, Kallara. 1952 Thomas, Penrhyn Francis, Suite 22, 3rd Floor, 49 Market-street, Sydney. 1946 Ps 2 Thompson, Nora (Mrs.), B.Sc., c/o Government Geologist, Lands Department, Port Moresby, Papua. 1956 Thomson, David John, B.sc., Department of Main Roads, Parkes, N.S.W. 1955 Thorley, Geraldine Lesley, B.A., 1290 Pacific-highway, Turramurra. 1954 | Tompkins, Denis Keith, 8.sc., 24 The Crescent, Lane Cove. 1940 Tow, Aubrey James, M.Sc., M.B., B.S., c/o Community Hospital, Canberra, A.C. 1949 Trebeck, Prosper Charles Brian, Jerilderie-street, Jerilderie. 1951 Tugby, Elise Evelyn (Mrs.), B.sc., c/o Department of Anthropological Sociology, Australian National University, Box 4, G.P.O., Canberra, A.C.T. 1952 Ungar, Andrew, pipl.ing., 6 Ashley Grove, Gordon. 1949 122 a Vallance, Thomas George, B.Sc., Ph.D., Geology Department, University of Sydney. 1953 Veevers, John James, M.Sc., Ph.D., D.I.c., Bureau of Mineral Resources, Canberra. 1921 Vicars, Robert, Marrickville Woollen Mills, Marrickville. 1935 Vickery, Joyce Winifred, m.sc., 17 The Promenade, Cheltenham. 1933 12 Voisey, Alan Heywood, p.sc., Professor of Geology and Geography, The Uni- versity of New England, Armidale. 1903 P10 |t{Vonwiller, Oscar U., B.sc., Emeritus Professor, ‘* Silvermists ’’, Robertson, N.S.W. (President, 1930.) 1948 Walker, Donald Francis, 13 Beauchamp-avenue, Chatswood. 1956 ‘Py Walker, Patrick Hilton, B.sc.agr., Research Officer, C.S.I.R.O., Division of Soils, c/o School of Agriculture, University of Sydney. tWalkom, Arthur Bache, p.sc., 45 Nelson-road, Killara. (President, 1943-44.) (Previous membership, 1910-1913.) 1948 Ward, Judith (Mrs.), B.sc., No. 650, c/o H.E.C., Wayatinah, Tasmania. way = © rg to 1913 P 5 |tWardlaw, Hy. Sloane Halcro, p.se. Syd., c/o Kanematsu Institute, Sydney Hospital, Macquarie Street, Sydney. (President, 1939.) 1919 P 1 |t{Waterhouse, Lionel Lawry, B.£. Syd., ‘‘ Rarotonga ’’, 42 Archer-street, Chats- wood. 1919 P 7 |tWaterhouse, Walter L., C.M.G., M.C., D.Sc.Agr., D.I.Cc., F.A.A., ‘‘ Hazelmere ”’, Chelmsford-avenue, Lindfield. (President, 1937.) 1911 P 1 |{Watt, Robert Dickie, M.a., B.sc., Emeritus Professor, ‘‘ Garron Tower’’, 5 Gladswood Gardens, Double Bay. (President, 1925.) 1921 {Watts, Arthur Spencer, ‘“‘ Araboonoo ”’, Glebe-street, Randwick. 1954 West, Norman William, B.sc., c/o Department of Main Roads, Sydney. 1949 Westheimer, Gerald, B.sc., Ph.D. 1951 Whitley, Alice, pPh.p. Lond., 39 Belmore-street, Burwood. 1951 PRP 3 Whitworth, Horace Francis, m.sc., Mining Museum, Sydney. 1949 Williams, Benjamin, 14 Francis-street, Artarmon. 1949 Williamson, William Harold, m.sc., 6 Hughes-avenue, Ermington. 1954 Wood, Clive Charles, B.sc., B.E., c/o S.M.H.E.A., Cooma, N.S.W. 1936 P 14 Wood, Harley Weston, M.se., Government Astronomer, Sydney Observatory, Sydney. (President, 1949.) 1906 P12 |{Woolnough, Walter George, D.sc., 28 Calbina-road, Northbridge. (President, 1926.) 1946 Wyndham, Norman Richard, m.p., m.s. Syd., F.R.C.S. Eng., F.R.A.C.S., 225 Macquarie-street, Sydney. 1952 Wynn, Desmond Watkin, B.se., c/o Department of Mines, Sydney. ASSOCIATES. 1956 Donegan, Elizabeth S., 18 Hillview-street, Sans Souci. 1956 Griffith, Elsie A., 9 Kanoona-street, Caringbah. Xvl Elected. 1949 1951 1952 1949 1946 1912 1953 1948 1948 8 HoNnNoRARY MEMBERS, Limited to Twenty. | Burnet, Sir Frank Macfarlane, M.D., Ph.D., F.R.S., F.A.A., Director of the Walter and Eliza Hall Research Institute, Melbourne. Fairley, Sir Neil Hamilton, c.B.E., M.D., D.Sc., F.R.S., 73 Harley-street, London, W.i1. Firth, Raymond William, M.A., Ph.p., Professor of Anthropology, University of London, London School of Economics, Houghton-street, Aldwych, W.C.2, England. Florey, Sir Howard, M.B., B.S., B.Sc., M.A., Ph.D., F.R.S., Professor of Pathology, Oxford University, England. Jones, Sir Harold Spencer, M.A., D.Sc., F.R.S., Astronomer Royal, Royal Observatory, Greenwich, London, 8.E.10. Martin, Sir Charles J., C.M.G., D.Sc., F.R.S., Roebuck House, Old Chesterton, Cambridge, England. O’Connell, Rev. Daniel J., S.J., D.Sc., Ph.D., F.R.A.S., Director, The Vatican Observatory, Rome, Italy. Oliphant, Marcus L., B.Se., Ph.D., F.R.S., F.A.A., Professor of Physics, The Australian National University, Canberra, A.C.T. Robinson, Sir Robert, M.A., D.Sc., F.C.S., F.1.C., F.R.S., Professor of Chemistry, Oxford University, England. OBITUARY, 1956-57. 1898. Walter Fitzmaurice Burfitt. 1943. Robert Desider Louis Frederick. XVii THE REV. W. B. CLARKE MEMORIAL FUND. The Rev. W. B. Clarke Memorial Fund was inaugurated at a meeting of the Royal Society of N.S.W. in August, 1878, soon after the death of Mr. Clarke, who for nearly forty years rendered distinguished service to his adopted country, Australia, and to science in general. It was resolved to give an opportunity to the general public to express their appreciation of the character and services of the Rev. W. B. Clarke ‘“‘ as a learned colonist, a faithful minister of religion, and an eminent scientific man’’. It was proposed that the memorial should take the form of lectures on Geology (to be known as the Clarke Memorial Lectures), which were to be free to the public, and of a medal to be given from time to time for distinguished work in the Natural Sciences done in or on the Australian Commonwealth and its territories; the person to whom the award is made may be resident in the Australian Commonwealth or its territories, or elsewhere. The Clarke Memorial Medal was established first, and later, as funds permitted, the Clarke Memorial Lectures have been given at intervals. CLARKE MEMORIAL LECTURES. The practice of publishing the lectures in the Journal began in 1936. Detivered. 1903. ‘‘ The Life and Work of the Rev. W. B. Clarke.’’ By Professor T. W. E. David, B.a«., F.R.S. 1906. ‘‘ The Voleanoes of Victoria’’ and ‘‘ The Origin of Dolomite ”’ (two lectures). By Professor E. W. Skeats, D.Sc., F.G.S. 1907. ‘‘ Geography of Australia in the Permo-Carboniferous Period’ (two lectures). By Professor T. W. E. David, B.A., F.R.S. “The Geological Relations of Oceania.”” By W. G. Woolnough, D.sc. ““ Problems of the Artesian Water Supply of Australia.” By E. F. Pittman, A.R.s.m. ““The Permo-Carboniferous Flora and Fauna and their Relations.””. By W. 8. Dun. 1918. ‘‘ Brain Growth, Education, and Social Inefficiency.” By Professor R. J. A. Berry, M.D., F.R.S.E. 1919. “‘ Geology at the Western Front.’’ By Professor T. W. E. David, ©.M.G., D.S.0., F.R.S. 1936. ‘‘ The Aeroplane in the Service of Geology.” By W. G. Woolnough, D.se. 1937. ‘‘ Some Problems of the Great Barrier Reef.’ By Professor H. C. Richards, pD.sc. 1938. ‘‘ The Simpson Desert and its Borders.’”’ By C. T. Madigan, M.A., B.Sc., B.E., D.Sc. Oxon, 1939. ‘‘ Pioneers of British Geology.”’ By Sir John 8. Flett, K.B.E., D.Sc., LL.D., F.R.S. 1940. ‘‘ The Geologist and Sub-surface Water.”’ By E. J. Kenny, M.Aust.1.M.M. 1941. ‘‘ The Climate of Australia in Past Ages.” By C. A. Sussmilch, F.c.s. 1942. ‘‘ The Heroic Period of Geological Work in Australia.” By E. C. Andrews, B.A. 1943. ‘* Australia’s Mineral Industry in the Present War.’ By H. G. Raggatt, D.sc. 1944. ‘‘ An Australian Geologist Looks at the Pacific.” By W. H. Bryan, M.c., D.Sc. 1945. ‘Some Aspects of the Tectonics of Australia.”’ By Professor E. 8. Hills, p.se., Ph.p. 1946. “‘ The Pulse of the Pacific.” By Professor L. A. Cotton, M.A., D.Sc. 1947. ‘‘ The Teachers of Geology in Australian Universities.”” By Professor H. S. Summers, D.Sc. 1948. ‘* The Sedimentary Succession of the Bibliando Dome : Record of a Prolonged Proterozoic Ice Age.”” By Sir Douglas Mawson, 0.B.E., F.R.S., D.Sc., B.E. 1949. ‘‘ Metallogenetic Epochs and Ore Regions in Australia.” By W. R. Browne, D.Sc. 1950. ‘* The Cambrian Period in Australia.”” By F. W. Whitehouse, Ph.p., D.Sc. (Unpublished.) 1951. ‘“‘ The Ore Minerals and their Textures.”” By A. B. Edwards, D.se., Ph.D., D.I.C. 1953. “‘Some Problems of Tertiary Geology in Southern Australia.” By M. F. Glaessner, Ph.D. Vienna, v.sc. Melb. a 1955. ‘‘ Some Aspects of New South Wales Gemstones.’ By R. O. Chalmers, A.S.T.C. AWARDS OF THE CLARKE MEDAL. Established in memory of The Revd. WILLIAM BRANWHITE CLARKE, M.a., F.R.S., F.G.S., ete. Vice-President from 1866 to 1878. The prefix * indicates the decease of the recipient. The list of recipients from 1878, the date of the first award, to 1929 may be found in Vol. LXXXIX (for 1955). Awarded. 1930 ~—_L. Keith Ward, B.a., B.E., D.sc., Government Geologist, Geological Survey Office, Adelaide. 1931 *Robin John Tillyard, m.a., D.Sc., Sc.D., F.R.S., F.L.S., F.E.S., Canberra, F.C.T. 1932 *Frederick Chapman, 4A.L.S., F.R.S.N.Z., F.G.S., Melbourne. 1933. Walter George Woolnough, D.sc., F.c.s., Department of the Interior, Canberra, F.C.T. 1934 *Edward Sydney Simpson, D.sc., B.E., F.4.c.1., Carlingford, Mill Point, South Perth, W.A. 1935 *George William Card, 4.R.s.m., 16 Ramsay-street, Collaroy, N.S.W. 1936 Sir Douglas Mawson, Kt., 0.B.E., F.R.S., D.Sc., B.E., University of Adelaide. 1937 J. T. Jutson, B.sc., Lu.B., 9 Ivanhoe-parade, Ivanhoe, Victoria. 1938 *Professor H. C. Richards, p.sc., The University of Queensland, Brisbane. 1939 *C. A. Sussmilch, F.c.s., F.s.t.c., 11 Appian Way, Burwood, N.S.W. 1941 *Professor Frederic Wood Jones, M.B., B.S., D.Sc., F.R.S., Anatomy Department, University of Manchester, England. 1942 William Rowan Browne, D.sc., Reader in Geology, The University of Sydney, N.S.W. 1943 Walter Lawry Waterhouse, M.C., D.Sc.Agr., D.I.C., F.L.S., Reader in Agriculture, University of Sydney. 1944 *Professor Wilfred Eade Agar, 0.B.E., M.A., D.Sc., F.R.S., University of Melbourne, Carlton, Victoria. 1945 Professor William Noel Benson, B.A., D.Sc., F.G.S., F.R.G.S., F.R.S.N.Z., F.G.S.Am., University of Otago, Dunedin, N.Z. 1946 Black, J. M., s.t.s. (honoris causa), Adelaide, S.A. 1947 *Hubert Lyman Clark, 4.B., D.sc., Ph.D., Hancock Foundation, t.s.c., Los Angeles, California. 1948 Walkom, Arthur Bache, pD.sec., Director, Australian Museum, Sydney. 1949 *Rupp, Rev. H. Montague, 24 Kameruka-road, Northbridge. 1950 Mackerras, Ian Murray, 8.Sc., M.B., Ch.M., The Queensland Institute of Medical Research, Brisbane. 1951 Stillwell, Frank Leslie, p.sc., C.S.I.R.O., Melbourne. 1952. Wood, Joseph G., Ph.p. Cantab., D.sc. Adel., Professor of Botany, University of Adelaide, South Australia. 1953. Nicholson, A. J., D.se., C.S.I.R.O., Division of Entomology, Canberra. 1954 *Clarke, E. de C., m.a., Emeritus Professor of Geology, University of Western Australia. 1955 Robertson, Rutherford Ness, B.sc. Syd., Ph.D. Cantab., C.S.I.R.O. Plant Physiology Unit, Sydney. 1956 *Tiegs, Oscar W., D.sc., F.R.S., Professor of Zoology, University of Melbourne. 1957. +Crespin, Irene, B.a., F.R.M.S., Bureau of Mineral Resources, Canberra, A.C.T. AWARDS OF THE JAMES COOK MEDAL. Bronze Medal. Awarded for outstanding contributions to science and human welfare in and for the Southern Hemisphere. 1947 Smuts, Field-Marshal The Rt. Hon, J. C., P.c., C.H., K.C., D.T.D., LL.D., F.R.S., Chancellor, University of Capetown, South Africa. 1948 Houssay, Bernado A., Professor of Physiology, Instituto de Biologia y Medicina Ex- perimental, Buenos Aires, Argentina. 1949 No award made. 1950 =‘ Fairley, Sir Neil Hamilton, c.B.E., M.D., D.Sc., F.R.S., 73 Harley-street, London, W.1. 1951 Gregg, Norman McAlister, M.B., B.s., 193 Macquarie-street, Sydney. 1952. Waterhouse, Walter L., M.c., D.Sc.Agr., D.I.C., F.L.S., ‘‘ Hazelmere ’’, Chelmsford-avenue, Lindfield. 1953. Rivett, Sir David, K.c.M.c., M.A., D.Se., F.R.S., 11 Eton Square, 474 St. Kilda-road, Mel- bourne, 8.C.2, Victoria. 1954 Burnet, Sir Frank Macfarlane, M.D., Ph.D., F.R.S., Director, Walter and Eliza Hall Research Institute, Melbourne, Victoria. 1955 Elkin, Adolphus P., m.a., ph.pD., Professor of Anthropology, University of Sydney. 1956 Clunies Ross, Sir Ian, Kt., C.M.G., F.4.4., D.V.Sc., LL.D., D.Sc., A.R.C.V.S., Chairman, C.S.I.R.O., Melbourne. >. b< AWARDS OF THE EDGEWORTH DAVID MEDAL. Bronze Medal. Awarded to Australian research workers under the age of thirty-five years, for work done mainly in Australia or its territories or contributing to the advancement of Australian Science. Awarded. 1948 Giovanelli, R. G., M.sce., Division of Physics, National Standards Laboratory, Joint Sydney. Award, Ritchie, Ernest, m.sc., University of Sydney, Sydney. 1949 Kiely, Temple B., D.sc.agr., Caroline-street, East Gosford. 1950 Berndt, Ronald M., B.A., Dip.Anthr., University of Sydney. Joint Berndt, Catherine H., mM.a., Dip.Anthr., University of Sydney. f Award. 1951 Bolton, John G., B.a., C.S.1.R.O., Division of Radiophysics, Sydney. 1952 Wardrop, Alan B., ph.p., C.S.I.R.O., Division of Forest Products, South Melbourne. 1953 No award made. 1954 Barnes, Eric Stephen, ph.p. Cantab., University of Sydney, Sydney. 1955 Womersley, Hugh B. 8., M.se., Ph.p., Botany Department, University of Adelaide. 1956 No award made. AWARDS OF THE SOCIETY. Money Prize of £25. 1882 John Fraser, B.A., West Maitland, for paper entitled ‘“‘ The Aborigines of New South | Wales.” 1882. Andrew Ross, m.p., Molong, for paper entitled ‘‘ Influence of the Australian climate and | pastures upon the growth of wool.” The Society’s Bronze Medal. Awarded from 1884 until 1896 for published papers. The Award was revived in 1943 for scientific contributions and services to science. 1884 W. E. Abbott, Wingen, for paper entitled ‘“*‘ Water supply in the Interior of New South Wales.” 1886 8S. H. Cox, F.G.s., F.c.s., Sydney, for paper entitled ‘‘ The Tin deposits of New South Wales.” 1887 Jonathan Seaver, F.G.s., Sydney, for paper entitled *‘ Origin and mode of occurrence of gold-bearing veins and of the associated Minerals.” 1888 Rev. J. E. Tenison-Woods, F.G.s., F.L.S., Sydney, for paper entitled ‘‘ The Anatomy and Life-history of Mollusca peculiar to Australia.” 1889 Thomas Whitelegge, r.R.M.s., Sydney, for paper entitled ‘* List of the Marine and Fresh- water Invertebrate Fauna of Port Jackson and Neighbourhood.” 1889 Rev. John Mathew, m.a., Coburg, Victoria, for paper entitled ‘‘ The Australian Aborigines.” 1891 Rev. J. Milne Curran, F.a.s., Sydney, for paper entitled “‘ The Microscopic Structure of Australian Rocks.” 1892 Alexander G. Hamilton, Public School, Mount Kembla, for paper entitled ‘‘ The effect which settlement in Australia has produced upon Indigenous Vegetation.” 1894 J. V. De Coque, Sydney, for paper entitled the ‘“‘ Timbers of New South Wales.” 1894 R. H. Mathews, t.s., Parramatta, for paper entitled ‘“‘ The Aboriginal Rock Carvings and Paintings in New South Wales.” 1895 C. J. Martin, pD.sc., M.B., F.R.S., Sydney, for paper entitled ‘‘ The physiological action of the venom of the Australian black snake (Pseudechis porphyriacus).” 1896 Rev. J. Milne Curran, Sydney, for paper entitled ‘‘ The occurrence of Precious Stones in New South Wales, with a description of the Deposits in which they are found.” 1943 Edwin Cheel, Sydney, in recognition of his contributions in the field of botanical research and to the advancement of science in general. 1948 Waterhouse, Walter L., M.c., D.Sc.Agr., D.1.C., F.L.S., Sydney, in recognition of his valuable contributions in the field of agricultural research. 1949 Elkin, Adolphus P., m.a., ph.p., Sydney, in recognition of his valuable contributions in the field of Anthropological Science. 1950 Vonwiller, Oscar U., B.Sc., F.Inst.p., Sydney, in recognition of his valuable contributions in the field of Physical Science. 1951 Penfold, Arthur Ramon, F.R.4.C.1., F.c.S., Sydney, in recognition of his valuable researches in the chemistry of Essential Oils. 1952 No award made. 1953 Walkom, Arthur Bache, D.sc., Sydney, in recognition of his valuable contributions to Palzeobotany. 1954 Mellor, David Paver, D.sc., F.R.A.C.1., Sydney, in recognition of his valuable contributions in the field of Chemistry. 1955 Woolnough, Walter G., D.Sc., F.G.S., in recognition of his valuable contributions in the field of Geology. 1956 Browne, William Rowan, D.sc., F.A.A., in recognition of his valuable contributions in the field of Geology. XxX AWARDS OF THE WALTER BURFITT PRIZE. Bronze Medal and Money Prize of £75. Established as the result of a generous gift to the Society by Dr. W. F. Burrirt, B.A., M.B., ch.M., B.Se., of Sydney, which was augmented later by a gift from Mrs. W. F. Burrirr. Awarded at intervals of three years to the worker in pure and applied science, resident in Australia or New Zealand, whose papers and other contributions published during the past six years are deemed of the highest scientific merit, account being taken only of investigations described for the first time, and carried out by the author mainly in these Dominions. Awarded. 1929 Norman Dawson Royle, M.D., ch.m., 185 Macquarie-street, Sydney. 1932 Charles Halliby Kellaway, M.c., M.D., M.S., F.R.c.P., The Walter and Eliza Hall Institute of Research in Pathology and Medicine, Melbourne. 1935 Victor Albert Bailey, M.A., D.Phil., Associate Professor of Physics, University of Sydney. 1938 Frank Macfarlane Burnet, m.p. Melb., php. Lond., The Walter and Eliza Hall Institute of Research in Pathology and Medicine, Melbourne. 1941 Frederick William Whitehouse, D.se., Ph.p., University of Queensland, Brisbane. 1944 Hereward Leighton Kesteven, D.se., M.D., e/o Allied Works Council, Melbourne. 1947 John Conrad Jaeger, M.A., D.Sc., University of Tasmania, Hobart. 1950 Martyn, David F., v.sc. Lond., F.R.S., Radio Research Board, c/o Commonwealth Observatory, Mount Stromlo, Canberra, A.C.T. 1953 Bullen, Keith E., M.A., Ph.p., F.R.S., Professor of Applied Mathematics, the University of Sydney. 1956 Eecles, John Carew, M.A., Ph.D. Oxon., F.R.S., F.A.A., F.R.C.P., Professor of Physiology, Australian National University, Canberra, A.C.T. THE ARCHIBALD D. OLLE PRIZE. Under a bequest from the late Mrs. Olle a prize, known as the “‘ Archibald D. Olle Prize ’’, will be awarded “‘ from time to time at the discretion of the Council to the member of the Society who in any year (in its opinion) submits to the Society the best treatise, or writing, or paper, on any subject coming within the province of the Society for that year’. 1956 Stanton, Richard L., ph.p., for his paper ‘“‘ The Paleozoic Rocks of the Wiseman’s Creek- Burraga Area, N.S.W.” AWARDS OF LIVERSIDGE RESEARCH LECTURESHIP. This Lectureship was established in accordance with the terms of a bequest to the Society by the late Professor Archibald Liversidge. Awarded at intervals of two years, for the purpose of encouragement of research in Chemistry. (THis Journat, Vol. LXII, pp. x-xiii, 1928.) Awarded. 1931 Harry Hey, c/o The Electrolytic Zine Company of Australasia, Ltd., Collins Street, Melbourne. 1933 W. J. Young, D.sc., M.Se., University of Melbourne. 1940 G. J. Burrows, B.sc., University of Sydney. 1942 J. 8. Anderson, B.sc., Ph.D. Lond., A.R.C.S., D.1.c., University of Melbourne. 1944 F. P. Bowden, pPh.p., se.p., University of Cambridge, Cambridge, England. 1946 Briggs, L. H., p.phil. Oxon., D.sc. N.Z., F.N.Z.1.C., F.R.S.N.Z., Auckland University College, Auckland, N.Z. 1948 Ian Lauder, m.sc., Ph.p., University of Queensland, Brisbane. 1950 Hedley R. Marston, F.R.s., C.S.I.R.O., Adelaide. 1952 A. L. G. Rees, p.sec., C.S.I.R.O., Division of Industrial Chemistry, Melbourne. 1954 M. R. Lemberg, pD.Phil., F.R.s., Institute of Medical Research, Royal North Shore Hospital, St. Leonards, N.S.W. 1956 G. M. Badger, pD.sc., Professor of Organic Chemistry, University of Adelaide. SS ee PRESIDENTIAL ADDRESS By Freperick D. McCARTHY, Dip.Anthrop. (Syd.). Delivered before the Royal Society of New South Wales, April 3, 1957. BART ale THE SOCIETY’S ACTIVITIES. The past year was the ninetieth of the Royal Society of New South Wales under this title, which was bestowed on May Ist, 1866. It was an important one for the Society. Due to the economies (dealt with in our annual report) effected in the Society’s accommodation and in its various activities, our financial position is now reasonably sound, and should continue to remain so in the future. To ensure that it will, members are asked to bear in mind our need for more members, and also of associate members, the latter being a new category introduced to cater for undergraduates and the wives of members. We need, too, more members from the biological and social sciences to make the Society more representative of Australian science as a whole. A glance at the presidential addresses and annual reports of recent years will reveal how earnestly the various Councils have considered ways and means of improving the Society’s financial position, its journal and its programme of meetings. The retiring Council is no exception, and it has, I feel, taken positive action in a number of ways that will be of permanent benefit to the Society. Perhaps the Society’s greatest need is for additional financial assistance with the printing of its journal, but to date no permanent source of such funds has presented itself. This year saw the introduction of a new award by the Society, the Archibald D. Olle Prize, for the best paper submitted for publication by a member of the Society. It is hoped that the idea which prompted the late Mr. Olle to finance this award, which is a money prize, will yield an increase of papers of the highest quality and also an increase in membership. The programme at the general meetings was an intensely interesting and important one. It inenided Symposia on electron-microscopy, radio-isotopes and radiophysics, blood-grouping and pasture developments. An address on Antarctic research, an evening devoted to the commemoration of great scientists and one to ‘the reading of papers completed the programme. All of these subjects are of topical interest and were dealt with clearly and lucidly by authorities in their fields. While some of the meetings attracted good audiences, others were very poorly attended, and your Council feels that members generally ‘do not support the meetings, and in doing so the speakers and the Council, as well as they should. One of the Society’s important functions is to bring together scientists from different disciplines to discuss their work, and our meetings provide an excellent opportunity for this purpose. I have great pleasure in extending my sincere congratulations to the recipients of ‘the Society’s awards for 1956. Their outstanding scientific work has been honoured by the Society with awards which now include the names of many great Australian scientists, as a perusal of the lists, two of which extend B yy FREDERICK D. MCCARTHY. back to 1878 and 1882, of recipients will reveal. The awarding of these honours is one of the most serious, and at the same time one of the most difficult, responsi- bilities of your Council each year. His Excellency the Governor, Lieutenant-General Sir John Northcott, K.C.M.G., K.C.V.G., C.B., one of the two patrons of the Society, stressed the important part that science and scientific societies are playing in the world today when he welcomed the President and Honorary Administrative Secretary to morning tea at Government House on June 11th, 1956. This has been a year in which the many participant nations began or con- tinued their preparations for the forthcoming Geophysical Year, and already the profound scientific results that will ultimately be revealed by this compre- hensive survey are becoming apparent. It is timely to note, also, the untiring efforts of UNESCO to bring about a greater understanding of one people’s problems by another, particularly of the backward and economically poor peoples of the world. In this connection we find that acculturation studies by anthropologists and sociologists are providing a mass of data that will be of the greatest value in helping such peoples towards a better future. The alleviation of their bitter struggle to live, to gain an adequate education for their children, and enlightenment for themselves, is one of the major problems UNESCO is attempting to solve. Science has not the need nowadays to publicize itself that it had formerly. The flood of popular scientific books and of articles in newspapers and magazines, and the regular sessions devoted to science on the radio and television, are spreading widely a broad interest in and knowledge of science among the lay population. That there has been a response is evident from the support given to such media of dissemination. The large audiences which attended the section meetings and public lectures of A.N.Z.A.A.S. at Dunedin this year, and the excellent coverage in the local newspapers, form good examples of the public interest in science today. Science has, nevertheless, a task of first-class importance facing it in the need to attract to its ranks a much larger number than it does now of the young men and women leaving school. It is essential to maintain the greater proportion of scientists and technicians needed in industry and government services today. There are wonderful opportunities for the young to gain a higher education, and better facilities would appear to be one solution of the problem. It is with the deepest regret that I record the death of Dr. Walter Fitz- maurice Burfitt, a benefactor of the Society who had a lifelong interest in science and the Society, as manifested in his munificent gifts, which made it possible to establish a highly esteemed award for original research work over a period of six years—one which has proved to be a genuine inspiration to scientific workers in both Australia and New Zealand. My own personal thanks are tendered most warmly to the Honorary Administrative Secretary, Mr. J. Griffith, for the very efficient manner in which he has carried out the exceptionally heavy duties imposed upon him during the year ; to the Honorary Editorial Secretary, Mr. F. N. Hanlon ; to the Honorary Treasurer, Mr. H. A. J. Donegan; and to the members of the Executive, the Council and various sub-committees for their loyal support and for their keen interest in the welfare of the Society. Vice-President Dr. Ida Browne’s watchful eye on our finances and her valued assistance in many other ways during the year merit special mention. Our thanks are due also to Miss M. Ogle, Assistant* Secretary, for her conscientious work during the year, and to Messrs. F. Daly and I. A. Crawford for their voluntary assistance in the reorganization of the library C—O a a S PRESIDENTIAL ADDRESS. 3 PAR ili: THEORETICAL CONSIDERATIONS OF AUSTRALIAN ABORIGINAL ART. During the past twenty years the interest of the applied and commercial artist, architect, book illustrator and the scientist in aboriginal art has increased tremendously. The motifs are now applied freely in all kinds of commercial work, and vulgar as much of this exploitation undoubtedly is, we are left with the feeling that it involves an interest in the aesthetic, apart from the scientific, values, and in the meaning of aboriginal art motifs. Although much of the art on portable objects such as weapons, utensils, ornaments and ceremonial objects, and also on the bodies of the people, is purely decorative in nature, there remains an important proportion of it that is serious and sacred when used in a ritual or ceremony. Depiction of single figures, unrelated to any others, is common in rock engravings and paintings, but in all kinds of aboriginal art—whether it be on wood, rock, the ground, body or other medium—planned compositions are featured. Thus a wide range of techniques, motifs and ideas is involved, every available medium is decorated in some areas, form is notable in weapons and design in ornaments and ceremonial objects. Aboriginal art is not a single style, concept or school, but is a mixture of a number of them. The styles we call realism and abstract are both represented. There is no denying that it is art in the true sense of the term, an art that has developed along different lines, and in a different context, to our own. Nevertheless it has been nurtured from time immemorial by religious and aesthetic inspirations and has never attained a state of free and uninhibited expression. It is timely, therefore, to discuss, more particularly in the terms of Franz Boas (1955), its variety, representative and formal modes of expression, tools and materials, form and content, and its chronological history. The Aborigines are a semi-nomadic hunting and food gathering people who live in small local groups confined to specific territories. The men paint and incise secular objects, decorate their bodies for corroborees and ceremonies, paint and engrave on rocks. The quality of their work varies, and that of talented craftsmen stands out in collections. To the men art is an integral part of their economic, social and ritual life. To the women it is a culture element of which they stand on the fringe, their work being limited mainly to body decora- tion and fashioning ornaments. In Arnhem Land, for example, the men decorate baskets made by the women. The status of the artist in aboriginal society is not a specialized one as a rule, but the old men, and the few men unable to hunt or fish through ailments, who remain in camp making weapons and the like for which they are rewarded in food and other articles (Sharp, 1934; Thomson, 1949), may be regarded as craft specialists, like those at Ngillipidji quarry in eastern Arnhem Land, where the men of a local group own the site and spend a great deal of their time in making and trading stone knives (Thomson, 1949) of the Leilira-type (McCarthy, Bramell and Noone, 1946). The important group of ceremonial leaders of clan and cult groups who make and decorate ritual objects, and paint sacred figures in the caves, approach most closely to specialists in tribal art as a whole. A system of hereditary craftsmen, like that of Polynesia, is not established in Australia. The art of the Aborigines, therefore, is principally an art of the men, and in its higher forms of the ritual leaders and occasional talented old individuals. Art, like music and language, is a means of expression, of perpetuating ideas, and of educating a people about the topography, fauna and flora of their habitat and about their own history. Whether art in aboriginal culture is a product of visual or mental processes, or of an innate visual sense of form, whether it arose out of a need and desire to employ symbols in magical and religious rites, BB Cs FREDERICK D. MCCARTHY. will probably never be known, and need not be debated here. It is a psycho- logical, emotional and visual link between the social, economic, magical and ritual life of the Aborigines. It combines an aesthetic impulse or desire for expression with inspiration from all aspects of life, and illustrates well the close- knit structure of a primitive culture. Sir Herbert Read (UNESCO, 1954) implied that environment is the principal ‘ause of different forms of art and of the comparative skill involved among primitive peoples, stating that ‘‘ a people hunting bison and reindeer across icy tundras, and retreating periodically to the shelter of caves, is bound to produce an art different from that of a people chasing kangaroos through the hot desert ”’. It may be pointed out that no other of the “prehistoric peoples of the world who lived in a similar cold environment to the Aurignacians and Magdalenians produced a cave art of such incomparable quality ; furthermore, that only a small proportion of the Australian Aborigines chased kangaroos in the hot desert and some, in fact, never chased them at all. But Aborigines who hunted and fished and retired to rock-shelters to paint have failed to produce realistic pictures of animals as technically fine as those in France and Spain for the reasons discussed later. Environment, then, may be rejected as the primary factor in dictating the artistic quality of aboriginal art. A much more potent factor is the possession by a people of a rich mythology and religion. On the Sepik River in New Guinea, the fascinating body of beliefs is expressed in a remarkable art of wood carving and painting, bark cloth, pottery and other media, but in central New Guinea the cultures are as bereft of art as they are of mythology and folklore. In Australia art is highly developed in areas where an inspiring body of beliefs exist, as in Arnhem Land, Kimberleys, central Australia and south-eastern Australia, and this factor would appear to me to be one of the most important ones in the development of aboriginal art. To Professor Elkin (in McCarthy, 1956a) aboriginal art arises for the most part out of, and finds its meaning and significance in, the sphere of ritual and belief, combined with an aesthetic sense, and Dr. Berndt (1952b) regards it in the same light. The combination of an active aesthetic desire, a dynamic cultural and mythological inspiration, and an environment providing suitable rock surfaces, has both induced and enabled the Aborigines to produce a vast array of engravings and paintings in many parts of the continent. The number of paintings runs into tens of thousands in Arnhem Land alone. It is likewise patent that the above desire and inspiration have produced the wealth of ornamentation, ritual objects and body decoration characteristic of aboriginal culture. ; Boas (1955) in analysing primitive art, postulated that the principle must be accepted of the fundamental sameness of mental processes in all races and in all cultural forms of the present day. To him the difference in thinking is due to the advantage bestowed on civilized people by their accumulation of written knowledge and their constant search for improvements and new ideas, as against the manner in which primitive peoples are conditioned by their culture to accept and maintain without question traditional customs and beliefs so that the logics of science are not the logics of life. Primitive man thinks in a pattern in which magic, belief and subjective causality are important factors. There are many examples of a similar mode of thinking among civilized peoples today. It is true that the aesthetic and psychological approach of aboriginal artists to their work is limited by their cultural background and setting. They thus lack the freedom of our own artists who are ever seeking new techniques and fresh ways of presenting their ideas. McElroy (1952) concluded, after applying tests to 40 Aborigines and 40 Whites, that there is little or no evidence for the existence of inter-racial good taste based upon inherited predispositions ; his PRESIDENTIAL ADDRESS. o results, he thinks, provide much evidence in favour of the view that the beauty of a visual object is almost entirely determined by the cultural conditioning of its perception. The Polynesians have emphasized the formal element in their art, in which conventionalized motifs are important mythological symbols. The art of Melanesia includes areas like the Massim in which formalism prevails, and others such as the Sepik district, with an intense emotional interest in representative form and in its emphasis by various sculptural devices. In Australia, a similar contrast may be drawn in the formalism of central Australia as compared with the naturalism of the Kimberley and Cape York cave paintings and of the Sydney-Hawkesbury district engravings. REPRESENTATIVE ART. Representative, realistic or naturalistic depictions comprise the greater part of aboriginal art as a whole, not only as major motifs in rock art but as dominant subjects in a setting of cross-hatching, chevron and other line patterns, and in a dotted field, in decorative art. The principal subjects are mammals and reptiles, fish and sea mammals with some of the batrachians and birds. There are few insects, shells, invertebrates or plants portrayed in most areas. Human beings and spirits, weapons and other objects are common motifs. Generally speaking, the art reflects the fact that it is principally a male sphere and conse- quently the affairs and activities of the women enter very slightly into it and chiefly in so far as they are associated with the female ancestral beings. On the Forrest River some women paint Brimurer, the Rainbow-serpent, and here, toe, the wife of a clan leader retouches totemic paintings during increase rites (Kaberry, 1935). In three analyses of aboriginal rock art that I have made the results have demonstrated a wide variation in the emphasis upon the artistic value of specific subjects. A few examples will suffice. In the Sydney-Hawkesbury engravings the fish, kangaroos, wallabies, emus, shields and boomerangs are depicted more frequently than all other subjects. While the economic life is thus proved to be an important source of inspiration, it is combined with a high frequency of ancestral and ritual beings and their activities, tracks and weapons. In the paintings of this area human beings are more abundant than animals, among which the kangaroo-wallaby group and their tracks, and fish, take second place to the goannas. Among both the rock engravings and paintings such important sources of food as the wombat, possum, koala, echidna, rodents and tortoise are rare subjects, as is the dingo, and whales are unknown among the paintings. Another important point of contrast is that culture-heroes are seldom pictured in these caves, and they are rare among the cave paintings of Groote and Chasm Islands, where we find the harpooning of dolphins, turtles and dugongs by men in small canoes to be the main subjects of the artists ; the animals are comparatively easy to kill by men armed with the detachable harpoon and dugout-canoe and form a major source of flesh-food, but in the Sydney-Hawkesbury district, where they are rarely shown in the rock art, the men no doubt found them difficult to spear from a frail bark canoe and consequently they were not of great importance economically. Lizards and weapons are common motifs in both localities. Whales, however, are featured among the Sydney-Hawkesbury engravings, being not infrequently stranded ; they are not shown among the Groote and Chasm cave paintings, although they inhabit the seas of this area and are portrayed in the Arnhem Land bark paintings. Fish are not depicted in some coastal sites in Australia and although used as a food by inland tribes they are almost completely neglected by the latter as an 6 FREDERICK D. MCCARTHY. art motif. Generally speaking, marine subjects are predominant in coastal areas, and animals—snakes, kangaroos, wallabies, lizards and emus principally— in the inland galleries. It is obvious that the relationship between economic and ritual subjects, as exemplified in the rock art, varies in many localities. The one may take precedence over the other in art, but the predominance of the most important economic species as art motifs within the framework of ritual is now becoming clearer as more groups of art are analysed. The northern Kimberley tribes believe that everything edible is painted in the Wandjina caves, when in reality only a small proportion of these items is so depicted (Love, 1930). As representative subjects, human and huge spirit beings are the dominating motifs in the Kimberley paintings and in the Sydney-Hawkesbury engravings, with them being found mythological figures like the Rainbow-Serpent and others often of curious shape, and also weapons and utensils. This complex of human, animal and spirit beings, of animals and tracks, weapons and utensils, forms a nucleus of representative art which extends from north-western Australia through the Kimberleys, Arnhem Land and the Northern Territory to parts of central Australia, and most of Victoria. The variation in subjects in the art of different parts of Australia and the many inconsistencies in different areas indicates that numerical analyses are needed from many localities and types of art to ascertain to what degree art is a reflection of local socio-economic and religious beliefs, and to make it possible to establish general principles or conclusions about this important aspect of aboriginal art. Representative motifs occur in all kinds of aboriginal art, including body painting, but for the purposes of this discussion the cave paintings will be dealt with in detail. The amazing uniformity of style in most parts of the continent is a good example of the stability of tradition in aboriginal culture. Whether we examine the paintings and engravings in New South Wales, Queensland, Arnhem Land or Western Australia, we find the same technical devices in use for portraying various subjects. These include depicting human beings from the front with varying numbers (or none) of fingers and toes, two eyes, no mouth or nose and often no ears or neck. The head is not enlarged because of its importance in belief as it is in Melanesia and Polynesia. The arms are outstretched or upraised, but in the Kimberley Wandjina cave paintings they are held stiffly at the sides of the body. The genitals are inconspicuous in the art. of some localities but of exaggerated size in other areas, notably Arnhem Land, but in the Sydney-Hawkesbury engravings the size varies according to the nature of the figure. Many variations occur in the postures of the human figures which include those seated, running, lying down, dancing, fighting and throwing weapons. The types range from the stick-men so gracefully refined in western Arnhem Land and Groote Eylandt to the huge culture-heroes of the Sydney-Hawkesbury engravings, and the stiff and poorly proportioned Wandjinas of the Kimberleys. Chronological studies of the mythology and relevant paintings throughout the continent would throw a great deal of light on the variations of styles. Macintosh’s study (1951) attempts such an analysis for some southern Arnhem Land paintings. The mammals, birds, fish, whales, dolphins and sharks are drawn in profile, each type being stylized, with a line for the mouth, one or two eyes, the outline of one limb for each pair of limbs ; fins are shown as part of the main outline of the fish. The numbers of toes and claws vary, and on the birds the wings are not shown unless in flight. Snakes are shown from the side or top view, but the lizards, frogs, turtles and tortoises are usually depicted from above. Thus the subjects are portrayed from the angle at which they are usually seen by the artists, although the poses vary widely in occasional portrayals from the basic PRESIDENTIAL ADDRESS. stylized type. Examples that might be mentioned are kangaroos hopping, emus running, or both of them feeding or standing on the alert. The young is often shown in the pouch of kangaroos, and the emu may be standing beside or sitting on its eggs. Groups of old and young emus and kangaroos are common. A peculiar error in drawing kangaroos is that the hump of the great loins is often misplaced as far forward as the neck. Stylization, however, even though it is so firmly established in aboriginal art, has not completely suppressed virtuosity. The artists are, in a sense, impressionists concerned primarily with posture and general outlines, depicted within traditional limits, but even under this restraint they have produced admirable examples of rock and other art which demonstrate a relatively high appreciation of line and mass in the best figures. Their pictures are mental images and symbols, and not representations drawn in the manner of a still-life painting. There is a lack of any indication of body contours or tones, and of fur, feathers or scales in most of the representative art. Exceptions are feathers shown in a simple way on cave paintings in the Kimberleys and both feathers and wings on birds, by areas of dots or lines, in the bark paintings of Groote Eylandt. But the general omission of these characters elsewhere reduces considerably the artistic possibilities and scope of the artists’ work. Neverthe- less, although the forms are constant many individual paintings demonstrate that some artists have the skill to infuse into their work a certain amount of animation in capturing a posture or action of an animal, to the degree in some instances of producing a figure of outstanding artistic merit. The techniques, on the whole, are simple. The painting methods display some measure of control even though much of the work is done on poor surfaces. It is difficult to determine the degree of interest of the Aboriginal artists in technique. One gains the impression from their cave and other paintings that the representation itself, the symbol, however technically deficient, is of greater importance than the method. Should this be true, it is probably the reason why their work has never risen to the great heights artistically of that of the Aurignacian and Magdalenian cave painters and engravers in the late Palzo- lithic period in southern France and northern Spain. The skill and knowledge of the aboriginal artists are certainly insufficient to imbue their pictures with the intense feeling and character of those of the Paleolithic artists, or with tonal variations of colour to show body contours. Aboriginal representative art is, on the whole, child-like in its conventions. As Boas said (1955), the principles of selection in both primitive and child art are based more upon the inclusion of essential features, such as two eyes when only one should be shown, than upon a mental image of the subject. Both adopt a symbolic style in which accuracy as such is not essential because they are more intent upon including the features by which they visualize a creature or human being, an approach that Dr. Adam (1948) has called intellectual realism, than of drawing what they can see from a certain angle. There is an inconsistency in this approach inasmuch as both groups of artists will show one leg or ear when they know two of each should be shown. FORMAL ART. To an artist nurtured and trained in a culture in which formal art is the norm it is highly probable that the enjoyment of form is as great as that derived from representative art. In Australia the comparatively intense development of formal or geometric art is probably due to introduced ideas, not to a chrono- logical evolution from the representative to the formal, but there must at the same time be an aesthetic interest even though the content is the more important element in the art. op FREDERICK D. MCCARTHY. In south-eastern Australia the formal designs consist of a concentric diamond set in a field of herringbone, chevron and sets of parallel lines incised at various angles. These designs illustrate well the manner in which the Aborigines set out a field and the importance of rhythmic repetition in aboriginal art. The diamond may be incised in parallel rows, or so placed that the flutings of one side form in turn one side of another concentric diamond, thus producing neat and complementary rows. It is sometimes distributed freely in no set order in the field. Where the designs are incised on cylindrical clubs, rubbings reveal that they are planned as though worked out for a flat surface. Occasionally small human or animal figures are introduced. The surfaces of the shields of this area are often divided into panels of design separated by plain bands to set off effectively the patterned panels. Each shield’s surface is treated in the mass, that is, the design is taken to the edges without a marginal band or is divided into panels in a vertical, horizontal or other symmetrical arrangement. i] AND DELTA REGION SKELETAL OWINANTLY PRED DEVELOPED ON ACID NO INTRUSIVES WETAWORPHICS 4 \\ A\\ \ WY \) WW POST - TERTIARY SOILS ILs so TERTIARY Text-fig. 2. 28 D. S. SIMONETT. (iii) Calcareous Grey Laterite Soils. In the low rainfall districts of Croydon (28 inches p.a.) and on Spring Creek, Lyndhurst, and Carpentaria Downs Stations near Hinasleigh (25 inches p.a.), ‘Calcareous Grey Laterite Soils have developed at the ends of long gentle slopes on granite and granodiorite. They are all of post-Tertiary age. A typical profile is given below. The Lyndhurst Profile. Occurs towards the end of a long }° slope (of two miles) on granodiorite near Bundock Creek on Lyndhurst Station. Grades upslope into a Yellow Podzolic soil. Open savannah woodland of Hucalyptus leptophleba-E. brownii vell. aff. Rainfall about 26 inches. 0-18 in. Grey to light yellowish grey loamy sand to sandy loam. 18-36 in. Yellow and grey reticulately mottled sandy elay with yellow-brown ironstone pisolites scattered throughout and in parts cemented into a firm hardpan. 36-70 in. Yellow sandy clay reticulately mottled with grey with weakly developed vertical cells and pipes of ironstone. 70-96 in. As above, with large calcium carbonate concretions up to one inch across or more. 96 in. Decomposing granodiorite. (iv) Lateritic Krasnozems. Lateritic Krasnozems (the term follows Stephens’ (1953) usage) are restricted to the lower slopes of Recent basalts,! mixed basalt and schist colluvial-alluvial materials, and occasional very ferruginous schists in the high rainfall areas of the east coast, notably in the Innisfail district (140 inches). The Mena Creek Recent Profile. Typical of end-of-slope laterite development on basalt in the Mena Creek area near Innisfail. Profile through end of 2°-3° slope, cut by cane tramway. This profile has been sampled and described by Teakle (1950), and analyses carried out by the Division of Soils, C.S.I.R.O. Rainfall about 150 inches. Original cover rainforest, now cleared for sugar cane. 0— 6 in. Disturbed by cutting. 6 in. to. Partly disturbed in the upper section by tram cutting. Light, brownish red light 4 ft. clay with occasional hard, irregular purplish-red ironstone masses up to four inches across. 4— 6 ft. Very light brownish red light clay. Contains numerous pieces of irregular ironstone, purplish-red in colour. Tendency to cellular structure in parts, in others a weakly developed cellular structure is apparent. Merges into 6-10 ft. Brownish red clay with large irregular, cellular ironstone masses. Merges into 10-18 ft. Yellow grey and olive grey clay with slight segregation of iron into small irregular masses. Appears to be a weakly developed ‘ pallid zone ”’ Teakle (1950) considers that this profile is that of a ‘‘ very immature laterite ”’ CATENARY RELATIONSHIPS OF THE LATERITE SOILS. The Tertiary Laterites. In areas of dissected Tertiary laterites a varied assemblage of soils develops on the different horizons exposed by erosion, as well as on transported material derived from the laterite. No study of these derived soils was made, but in all probability they follow a pattern similar to that outlined by Stephens (1946) for southern Australia. Where the site is undisturbed the catena members depend upon the acidity of the parent materials and the degree of slope. A form of listing is adopted below (Table 1) to make the various sequences clear. 1 Professor W. ie Bryan, University Py: Queensland, considers these basalts to be very late Pleistocene or early Recent in age (personal communication). LATERITE AND OTHER IRONSTONE SOILS IN NORTH QUEENSLAND. 29 TABLE 1 Acidity of Parent Degree of Catenary Sequence Moving Downslope to Material. Slope. the Right. | | Acid— | More than 1—2°. | Krasnozem—transitional—Lateritic Red Earth. Intermediate | shales, Less than 1—2°. Transitional Lateritic Red Earth—Lateritic Red Earth. granodiorite, ete. | Very long and | Transitional Lateritic Red Earth—Lateritic Red Earth— gentle, —_ less Grey Laterite Soil. than 1°. Acid More than 1—2°. | Red Podzolic—Yellow Podzolic—transitional—Grey Laterite sandstone, Soil. granite, etc. Very gentle long | Red Podzolic—Yellow Podzolic—transitional—Grey Laterite slopes. Soil—Meadow Podzolic. The last sequence listed above is of considerable interest for the light it throws on the nature of the water-table fluctuations on long very gentle slopes and may be examined further. The evidence for this sequence (namely Red Podzolic-Yellow Podzolic—transitional-—Grey Laterite Soil-—Meadow Podzolic) is based upon an interesting topographic succession described from the Northern Territory by Stewart (1954) and a parallel sequence in north Queensland developed on the broad, low, weakly-dissected shaly-sandstone mesas (mesa walls 15-20 feet high) between the Gilbert and Mitchell rivers to the north of Croydon. These examples are illustrated in Text-figure 3. LATERITIC RED EARTH (BERRIMAH) AND LATERITIC PODZOLIC SOILS (KOOLPINYAH & FLORINA) SOIL SURFACE iV LATERITE MEADOW PODZOLIC See em TCHOP CE ale LATERITE OR FERRUGINOUS CONCRETIONS (MARRAKAI) SOILS Fe IRI roe v LATERITIC RED EARTHS AND LATERITE GREY LATERITE SOILS MEADOW PODZOLICS I} SOIL SURFACE “ We LATERITE OR FERRUGINOUS CONCRETIONS Text-fig. 3.—Topographic successions of laterite and meadow soils of Tertiary age in the 1. Katherine-Darwin Area (after Stewart, 1954); 2. Lower Cape York Peninsula to the north of Croydon. Referring to the example from the Territory, Stewart notes that ‘‘ in many places massive laterite outcrops around the higher margins of the Marrakai soils (described as Meadow Podzolics) of the creek flats or depressions. Apparently the ferruginous zone represents the range of fluctuation of the water-table in the wet season. In the Marrakai soil the water-table is above the surface of the soil and the soil undergoes similar pedological processes to those of the subsoils of lateritic soils. In the anaerobie conditions of the waterlogged soil iron is reduced 30 D. S. SIMONETT. to the ferrous form and is removed upwards from the solum. Even though flooded, the soils are very strongly leached, i.e. they must be reasonably per- meable, and the water-table above soil level is apparently due to their low topographic position and the high regional wet season water-table.’’ In general, the same topographic relations hold in the zone to the north of Croydon and Stewart’s argument is applicable there also. Although these seasonally inundated soils may have been subjected to some slight post-Tertiary erosion, they probably approximate closely to the original Tertiary lowest members. From these examples we might conclude that on very gentle long slopes on acid rocks the lowest areas subject to seasonal ponding would not tend to develop Grey Laterite Soils because the water-table fluctuations would not be of the type needed for their formation, whereas at the base of slightly steeper slopes where long-continued surface ponding is restricted they would constitute the lowest member. The areas of excessively high rainfall on the east coast provide a partial exception to this generalization for even on slopes which elsewhere would carry Grey Laterite Soils some surface ponding is common and Meadow Podzolics are often noted in such inundated zones. The Post-Tertiary Laterites. In the post-Tertiary laterites, as is the case with the Tertiary group, parent materials, slope and also rainfall greatly influence the course of development of the laterites and their associated soils. In Table 2 given below some general relationships are shown. TABLE 2. Present Annual Parent Rainfall in Degree of Catenary Sequence Moving Down- Material. Inches. Slope. slope to the Right. Basalt. 40 to 140 5°-+ for upper | Krasnozems on all slopes. East coast to 1-2° on and Atherton Tableland. lower slopes. Recent 140+ As above. Krasnozems — Yellow Brown Latosols Basalt (occasional and on _ basalt only)— and very Lateritic Krasnozems. Well developed Ferruginous in the Innisfail district. Schist. Granite. 25 to. 20 As above. Krasnozem (on ferruginous schists and basic granites and in the higher rainfall areas) or Red Podzolics—Red Podzolics— Yellow Podzolics — transitional — Grey Laterite Soils. Hast Coast and Inland districts. ; Granite 120+ andin some | As above plus | Krasnozems — Red Podzolics — Yellow and favourable sites, gentle end of | Podzolics—Meadow Podzolics. East Schist. 90+. slope less than coast, especially the Tully and Innisfail ie areas. Alluvial 75+ Level to very | Krasnozem — Red Podzolics — Yellow Terraces. gentle. Podzolics—Grey Laterite Soils (or in some instances Grey Ironstone Soils). LATERITE AND OTHER IRONSTONE SOILS IN NORTH QUEENSLAND. oil The following comments are relevant to a study of the preceding table: (i) Generally speaking, the Pleistocene and Recent laterites have formed on steeper slopes than the Tertiary examples. They occupy a smaller pro- portion of the catena, and are more markedly restricted to the lower slopes. (ii) If the present rainfall pattern is a reasonable guide to that of the Pleistocene, then it seems that laterite will form on acid rocks under considerably lower rainfalls than on basic rocks. (iii) On basaltic parent materials Lateritic Krasnozems are found only on the lower slopes of Recent basalts in the high rainfall area around Innisfail (140+ inches p.a.), while the higher sites are characterized by Krasnozems. In several instances soils with distinct affinities with Yellow Brown Latosols were observed on sites intermediate between the Krasnozems and the Lateritic Krasnozems in the Innisfail district, but it is not known whether they are an invariable intermediate member of the catena. Elsewhere in the coastal belt where rainfalls are lower than at Innisfail, Krasnozems generally occupy all sites, including the lowest on the Recent basalts. Hven on the Atherton Table- land, where rainfalls range up to 150 inches, no Lateritic Krasnozems have been observed by Teakle (1950) or the writer either on the Recent basalts in the north or on the Tertiary flows in the south. The hilly nature of the southern high rainfall zone of the Tableland and the sharp decline in rainfall (40 to 80 inches) over the more undulating and rolling lands to the north evidently has not favoured laterite development. It would appear, therefore, in north Queensland that only in undulating to rolling country where rainfalls exceed 140 inches can the persistent high water-tables needed for the formation of laterite at moderate depth be maintained on the normally free-draining Krasnozems which tend to develop over basalts at rainfall levels above about 40 inches. (iv) Along the east coast where rainfalls are above 120 inches—and in some areas where they are as low as 90 inches per annum—laterite development is uncommon on granite and schist. This contrasts to the situation on basalt, where lateritic soils do not develop until some 140 inches are received. This contrasting situation. is probably in part related to the more frequent occurrence of long very gentle slopes and flats at the base of granitic and schistose hills than is the case with the shorter and more undulating to rolling slopes on basalt. On these very gentle slopes, backed by a considerable sheet-flood catchment upslope, many low-level sites on granite and schist are waterlogged for almost the entire year and apparently do not experience water-table fluctuations of the type needed for laterite profile development. In this high rainfall area where even the dry season from July to October averages more than 16 inches sheet and imbricate rill flow of excess water is common across the gentle aprons skirting the steep hills. In such areas Meadow Podzolies, rather than Grey Laterite Soils, are the norm! (v) The Krasnozems and Red Podzolics which are t pical of all slopes over 2° on schistose alluvial-colluvial slopes to the south of Cairns (in the rainfall range 90+ inches) in some instances have lateritic ironstone and mottled and pallid horizons occurring in the very deep subsoils 15 to 25 feet or more below the surface. Fine examples of these deep horizons are exposed by deep stream gashes in the Mulgrave Valley colluvials between Meringa and Cairns; on road cuttings between Tully and Innisfail; and at Bingil Beach to the east of Tully, Whether these deep horizons are related to present-day deep water-table fluctuations or are related to earlier water-table positions—and hence are reliet— the writer cannot say. However, the marked dissection of the exposure at Bingil Beach is at least suggestive of the latter possibility. 32 D. S. SIMONETT. GENESIS OF THE LATERITES. On the genesis of laterite soils in Australia there is a general consensus of opinion on the role of water-table fluctuations by which the pallid, mottled and portion at least of the ironstone horizons are developed. Stephens (1946), Whitehouse (1940), Teakle (1950) and Hallsworth and Costin (1953) have discussed the mechanism thoroughly, and the latter in particular have pointed out several possible ways in which the appropriate water-table fluctuations could arise in both tropical and sub-tropical areas, noting that water-table movements on the lower, gentle slopes of hills as well as regional water-tables on long gentle slopes could be involved in the production of laterite soils. These writers agree that—irrespective of the nature of the surface horizons—a well- developed lateritic soil contains an ironstone horizon in the subsoil, underlain in turn by a mottled and then a pallid zone, and then, in occasional instances, by a silicified horizon of “ billy’. There is also agreement that during the formation of these soils the pallid zone, and to a lesser degree the mottled zone, are the site of a permanent or semi-permanent water- table, and that seasonal fluctuations in the water-table take place up to and occasionally above the level of the ironstone horizon. The development of the ironstone horizon is attributed by Teakle (1950) to deposition from iron-charged ground waters, the iron being derived ‘‘ (a) from the surface as the leaching waters descend, (b) from remote places, as ground waters slowly move laterally under oravity, and (c) from the water saturating the pallid and mottled zone, where reducing con- ditions will prevail . . . (and deposition) would naturally occur at or near the fluctuating capillary fringe (of the water-table) where intermittent aeration would promote oxidation of the ferrous carbonate to ferric oxide ”’. As noted in the profiles described earlier, the soil overlying, and in part included within the ironstone horizon, varies from a Krasnozem to a Red Earth, to a podzolic type soil (the Grey Laterite Soil) depending on the parent material, topographic site, rainfall and age. For the Grey Laterite Soils the development of the podzolic type surface soils may be pursued further around the question ‘did the podzolic type surface horizons develop contemporaneously with the deep-seated portions of the profile? ” Prescott (1931) and Stephens (1946) consider that both surface and deep profile features developed at the same time, but Hallsworth and Costin (1953) have stated that ‘ this does not appear to be necessary ”? in New South Wales. They argue that, ‘‘ in so far as the Monaro and Sydney Laterites are concerned, the upper podzolized layer is more logically interpreted as having been super- imposed after lateritization as an effect of a strongly podzolizing climate (during the Pleistocene)’. By implication this same argument may be applied to other areas of Australia. In the lower Peninsula the following observations suggest that contemporaneous development of the whole profile is normally the case: (1) In the middle courses of the Einasleigh, Lynd and Etheridge Rivers are Mesozoic shaly sandstones which were strongly lateritized during the Tertiary, and were then gently warped and dissected into low mesas during and after the Kosciusko uplift of late Pliocene-early Pleistocene time. Grey Laterite Soils are now found, along with other soils, on both the mesa edges and in the interior portions of the mesas. Now, if the ‘development of the upper grey podzolized horizon of the Grey Laterite Soils was confined to the Pleistocene, then we could reasonably expect to find considerable differences in profile between the free- draining areas at the mesa edges and the much less free-draining areas in the centres of the mesas. No such differences were observed in uneroded sites. Further, if podzolization were a Pleistocene phenomenon, then we could expect to find little difference in profile and intensity of podzolization between the various soils of the free-draining sites at the mesa edges. This is not the case, LATERITE AND OTHER IRONSTONE SOILS IN NORTH QUEENSLAND. 33 and in fact there is a variety of soils matching those of the crests and troughs of the extremely gentle undulations of the mid-most parts of the mesas. In essence, then, the soils found on the mesas appear to reflect the pre-dissection topography and show little relation to the existing topography, which pre- sumably was also typical of much of the Pleistocene. The writer concludes from this that, in the main, development of the surface as well as the deep profile features of the Grey Laterite Soils, antedated the Kosciusko uplift, and probably occurred at the same time. (2) Grey Laterite Soils on granite and schist were observed in the Pleistocene valleys of the east coast, and on the lower slopes of the broad Pleistocene surfaces etched in the Tertiary upland surface at the headwaters of the Burdekin, Gilbert and Etheridge Rivers. These soils have also developed on the abandoned Pleistocene alluvials of the Mulgrave River near Cairns and on other Pleistocene terraces between Cairns and Tully. All these profiles are broadly similar to those on the mesas described above. Bearing in mind the site and time of formation differences between these groups, it is difficult to account for the development of these similar profile features through the action of two separate processes widely separated in time. For these reasons, then, it is considered that polygenesis as a means of developing the Grey Laterite Soils is doubtful ; contemporaneous development seems much the more likely. It is suggested that the same arguments hold for the development of the Lateritic Red Earths during the Tertiary and for the Lateritic Krasnozems on Recent basalts. This argument seems much less certain for the Calcareous Grey Laterite Soils found on granite in the Croydon and Einasleigh districts. In these low rainfall areas (28 inches or less) secondary carbonate retention may be a relatively recent imposition on laterites formed during the Pleistocene, such retention presumably following from a shift to drier conditions after the Pleistocene. In other parts of Australia there is much evidence that late Pleistocene rainfalls were higher than the present (Crocker and Wood, 1947). No clear-cut evidence to this effect is available in the lower Peninsula. However, the presence of relict: areas of Indo-Malaysian flora in the headwaters of the Einasleigh River under rainfalls of about 30 inches, and the development of Tropical Black Earths on Recent basalts alongside leached red soils on earlier flows (in the same headwater zone), is at least suggestive of such a change. With the possible exception of the low rainfall areas above there would seem to be no reason why the lateritization process is not still operative through- out the lower Peninsula, although it may perhaps be geared to a different mean water-table position compared to earlier periods. Marked water-table fluctua- tions occur each year with the onset and passage of the monsoon and during the wet season reducing conditions exist as close to the surface as 6 to 12 inches in many low-lying sites. OTHER IRONSTONE SOILS. In addition to the post-Tertiary Grey Laterite Soils and Caleareous Grey Laterite Soils and Calcareous Grey Laterite Soils occurring respectively in the high and low rainfall areas of the Peninsula, there are other ironstone soils with closely similar upper-profile features, but they lack the companion horizons of mottled and pallid kaolinitic clay and ironstone ‘“ pipes ’’, which are replaced by non-mottled or weakly mottled clays. The development of these non- mottled or weakly mottled clays in the place of the companion horizons implies that such water-tables as do develop in these soils are perched above an impervious clay horizon, and that there is little deeper water-table development except perhaps at levels well below the surface. Although some workers in 34 D. S. SIMONETT. Australia group such profiles with the fully developed laterite containing companion horizons, the writer feels that they should be separated. Until detailed work on these soils enables more suitable terms to be devised, Grey Tronstone Soils and Caleareous Grey Ironstone Soils may be used for con- venience. Typical profile data are as follows: Grey Ironstone Soils. Grey Ironstone Soils were observed mainly in low-lying sites on Pleistocene terraces, notably along the east coast streams under rainfalls of 75 inches or more, and also on the alluvials of the Gilbert and Mitchell Rivers where present rainfalls range from 30 to 40 inches. The writer is unsure to what extent the sites along the distributory zones of the Gilbert and Mitchell Rivers should be regarded as Pleistocene or as Recent. The Mulgrave Profile. Onthe abandoned Pleistocene terrace of the Mulgrave River near Gordonvale, to the south of Cairns. Lowest portion of terrace. Originally dry sclerophyll forest of Hucalyptus alba, Tristania suaveolens, Melaleuca leucadendron and numerous acacias. Rainfall about 75 inches. 0- 6 in. Brownish grey sandy loam; numerous soft, earth pisolites; pH 5-6, clay 17%; silt 14%, organic carbon 3-36%, chlorides 0-01%. 6-18 in. Light grey and light yellow grey sandy clay loam ; numerous firm pisolites becoming larger with depth; pH 5-5, clay 23%, silt 14%. chlorides 0-01%. 18-30 in. Black and yellow pisolitic rubble ; discrete ; firm ; but not exceptionally hard where not exposed to the air. On exposure the outer surfaces become very hard and are cemented together. pH 5-1. 30-54 in. Red scattered pisolites in a yellow clay loam; pH 5-1. 54-80 in. Red and yellowish red sandy loam becoming sandier with depth. The catena on these Pleistocene alluvials in the high rainfall areas consists of Krasnozems or Red Podzolic Soils in the higher areas, the former generally being found on the heavier textured alluvials ; these grade downslope through Yellow Podzolics into the Grey Ironstone Soils. It is important to note that in other sites on these alluvials where the water-table fluctuations are of the appropriate type, Grey Laterite Soils occur. Clearly, then, there is considerable affinity between these two groups of lower member soils with ironstone horizons— but there is still the necessity to separate those with companion horizons from those without. Insufficient sampling was carried.out to determine the associated soils in the low rainfall areas. Calcareous Grey Ironstone Soils. Examples of Calcareous Grey Ironstone Soils are to be found in the low rainfall area (28 to 35 inches) to the west of Croydon on unconsolidated materials probably to be correlated with Whitehouse’s (1940) Pliocene Glendower Series. The Strathmore Profile. Site seven miles west of Strathmore homestead. End of long $° slope. Savannah woodland of Eucalyptus microtheca, E. polycarpa and Petalostigma pubescens. Rainfall about 30 inches. 0-12 in. Ash grey very fine sandy loam; micaceous. 12-24 in. Ash grey very fine sandy loam with occasional ferruginous pisolites. 24-48 in. ¥ellow-brown clay with numerous ferruginous pisolites merging into a hardpan about 34 inches. 48-60 in. Yellow brown clay. 60-70 in. Yellow brown clay with calcium carbonate concretions. These soils occupy only a small part of the catena, the Brown Soils of Light Texture (?) which occur upslope covering a much greater area. It is possible that they may have some affinities with the solodic soils described by Halls- worth, Costin and Gibbons (1953). LATERITE AND OTHER IRONSTONE SOILS IN NORTH QUEENSLAND. 35 SUMMARY. Soils containing ironstone concretions and pans are widespread in the lower Cape York Peninsula of north Queensland. The most common of these soils fall into two main groups : (1) The laterite soils, characterized by subsoil iron coneretions and vermicular and cellular ironstone overlying mottled and ‘‘ pallid ”’ horizons, and apparently formed by fluctuations of considerable amplitude etmecn the wet and dry season levels of the water-table. Four major types occur: (i) Grey Laterite Soils, (ii) Lateritic Red Earths, (iii) Calcareous Grey parents Soils, and (iv) Lateritic Krasnozems. Formation of laterite has occurred in the Tertiary, Pleistocene and. Recent. Some conditions under which laterite development does not occur (in conjunction with severe sheet flooding) in low- lying sites are described. Common catenary relationships are also given. (2) The ironstone soils also possess horizons of ironstone concretions, but lack the deep mottled and pallid horizons which are replaced by non-mottled or slightly mottled clays. In these soils, temporary wet-season waterlogging above a clay horizon—rather than wholesale water-table fluctuations—appear to be important in developing the iron pans. Two main types occur: (i) Grey Tronstone Soils and (ii) Calcareous Grey Ironstone Soils. Both appear to be of post-Tertiary age. ACKNOWLEDGEMENTS. Grateful acknowledgement is made to Professor E. G. Hallsworth and Mr. F. A. Barnes of the University of Nottingham for helpful criticisms ; and to Mr. G. A. Stewart, who kindly allowed the writer access to his report on the soils of the Katherine-Darwin region before it was published. The field work for this paper was carried out while the writer held a Research Fellowship in the University of Sydney. Grateful acknowledgement is made to the Research Grants Committee of the University of Sydney for the Fellowship and for financial assistance. REFERENCES. Australian Atlas of Resources, 1952. ‘‘ Soils Map of Australia.’”’ Department of the Interior, Canberra. Crocker, R. L., and Wood, J. G., 1947. ‘‘ Some Historical Influences in the Development of the South Australian Vegetation Communities and Their Bearing on Concepts and Classification in ergata Trans. Roy. Soc. S. Aust., 71, ie Hallsworth, G., and Costin, A. B., 1953. ‘“‘ Studies in Pedogenesis in New South Wales. IV. The eee Soils.” J. Soil Sci., 4, 24. Hallsworth, E. G., Costin, A. B., and Gibbons, F. R., 1953. ‘‘ Studies in Pedogenesis in New South Wales. WI. On the Classification of Soils Showing Features of Podzol Morphology.”’ Ibid., 4, 241. Prescott, J. A., 1944. ‘“‘ A Soil Map of Australia.” C.S.I.R. Aust. Bull. 177. Stephens, C. G., 1946. ‘‘ Pedogenesis Following the Dissection of Lateritic Regions in Southern Australia.” C.S.I.R. Aust. Bull. 206. e 1953. ‘*‘ A Manual of Australian Soils.”? C.S.I.R.O., Melbourne, Australia. Stewart, A. G., 1954. “The Soils of the Katherine-Darwin Region, Northern Territory.” Soil Publication No. 6, C.S.I.R.O., Melbourne, Australia. Teakle, L. J. H., 1950. ‘‘ Notes on the Soils of Coastal Queensland.” Univ. Q’ld. Papers, Faculty of Agriculture, 1, 1. Whitehouse, F. W., 1940. ‘‘ Studies in the Late Geological History of Queensland.” Univ. Q’ld. Papers, Dept. Geology, 2, 1. NotTE oN TEXT-FIGURE 2. The soil boundaries given in Text-figure 2 are based upon limited reconnaissance, extended by discussions with graziers, and the use of Tri-metrogon aerial photographs (for the southern half of the area) both before and after going into the field. Useful four miles to one inch military maps were available for the Atherton, Einasleigh, Normanton and Galbraith areas. One inch to one mile military maps were used for the east coast and Atherton Tableland areas. MAGNETIC PROPERTIES OF ROCKS. By H. NARAIN and V. BHASKARA RAO. Department of Geology and Geophysics, The University of Sydney. (Communicated by Dr. Ipa A. BROWNE.) Manuscript received, June 11, 1956. Read, April 3, 1957. ABSTRACT. A critical review of the previous researches in this field has been made. The phenomenon of hysteresis in rocks, and the variation of susceptibility with magnetizing field and the magnetite content of rocks have been studied. A modified method of obtaining the hysteresis loops on the cathode-ray oscillograph has been developed. Severe scatter in the relationship between the specific susceptibility and the normative, modal and volume magnetite contents of the rocks has been observed. However, an empirical linear relationship between the specific susceptibility at a field of 8-8 oersteds and the normative magnetite content has been established. . The results, though quantitatively difficult to analyse and interpret, indicate qualitatively the ferromagnetic behaviour of rocks. This is primarily due to the presence of magnetite, though other magnetic minerals also contribute to the phenomenon. INTRODUCTION. Ever since the magnetic behaviour of lodestone was discovered, numerous investigators have been engaged in the determination of the magnetic properties of rocks and minerals. The volume of data accumulated over the years is so variegated and huge that, now, the study, of any one of these properties has become a specialized branch. Particular significance is attached to the studies in magnetic susceptibilities because of their application in problems of geo- physical exploration. The discovery of the Kursk anomaly gave an impetus to pooling up of magnetic data on rocks and minerals and resulted in a compre- hensive survey by Reich (1941) and many others, of the magnetic susceptibility of various minerals. In spite of the large range in values quoted for the susceptibility of even the same type of rocks it is now, more or less, generally agreed that the susceptibility of rock is mainly dependent on the magnetic minerals—especially magnetite— contained in the rock. However, susceptibility determinations are complicated, among others, by (i) the magnetizing field, (ii) the previous history of the rock, (iii) the grain size of magnetic particles contained in the rock, (iv) the chemical composition, and (v) petrological characteristics of the rock. Some of these factors attracted the notice of the authors, who were primarily engaged in the detailed magnetic survey of the Sydney Basin and of the Prospect intrusion in N.S.W. An apparatus was, therefore, set up to obtain the hysteresis curves for various rock samples up to a maximum magnetizing field of 176 oersteds. Variation of specific susceptibility of 38 rock samples in the magnetic field range of 44 to 176 oersteds has been studied. The investigations have revealed that in general the susceptibility decreases with increasing field strength. Hysteresis and the change in shape of the hysteresis loops with increasing field strength indicate the ferromagnetic behaviour, which is primarily due to the presence of magnetite in the rock. MAGNETIC PROPERTIES OF ROCKS. ot Variation of specific susceptibility with normative magnetite content was studied for a number of samples. The studies indicate that, due to a large number of factors affecting the results, it may be hard to establish a simple relation which will have universal prediction value. PREVIOUS RESEARCH. Research workers like Rucker (1890), Takagi (1913), Wilson (1920-21), Barret (1932), Hallimond (1933), Nagata (1940, 1943), Werner (1945), Duffin (1946), Bruckshaw and Robertson (1948), Bruckshaw and Rao (1950) and Mooney (1952) have contributed a lot to the experimentation side as well as interpretation of susceptibility determinations of different rock types. Ricker established that the average susceptibility of basic rocks is relatively very high. Takagi observed that the susceptibility decreases with increasing field but in strong fields this decrease becomes less. Various authors have attempted correlation between susceptibility and magnetic content of rocks but they have used different methods to obtain a quantitative estimate of the magnetite contained in a rock. Nettleton and Elkins (1944) have discussed these methods with their relative merits. It is evident from a consideration of the work of these investigators that (i) the susceptibility values show a very considerable scattering even for the same volume percentage of magnetite, (ii) this scattering indicates definitely a large range of variation in the susceptibility of magnetite itself, (iii) the suscepti- bility does “not decrease linearly with magnetite content at least for samples very rich in magnetite, and (iv) the failure of the assumption that the susceptibility and demagnetization factor of magnetite for a particular rock type are uniform may be the cause, in a large measure, of the large scatter observed in the data. However, it is possible to obtain certain conclusions as to the relative magnitudes of the susceptibilities encountered in different rock types. It is to be remembered that a number of factors affect the susceptibility determinations. Hence, such conclusions as can be drawn from these measurements have no more than order-of-magnitude significance. Still it is worth while attempting a correlation between such laboratory measurements and the ground and aerial magneto- metric surveys. EXPERIMENTAL TECHNIQUE. The aim of the present investigations has been to obtain the hysteresis curves for various rock samples, in the form of cylinders, up to a maximum magnetizing field of 176 oersteds. The principle of the experimental technique is essentially the same as the one employed by Bruckshaw and Rao, with the ae H curves, the [—H curves were themselves directly obtained on the oscillograph screen. An electrical circuit, which integrates the differential voltage set up in a system of three previously balanced pick-up coils, is introduced to give a vertical deflection on the oscillograph, which is directly calibrated in terms of absolute values of intensity of magnetization I. difference that in the present case, instead of Coil System. The coil former consists of insulating Permali (Text-fig. 1). Six Permali discs are mounted on this former at proper places by suitably turning down the rod on a lathe at those places. The lengths have been so designed that not only the whole coil system is symmetrical about its centre, but also that when the specimen S is pushed into its limit the centre of the specimen coincides with the geometric centre of the coi! system. D 38 NARAIN AND RAO. oe. bons — — -S:Bem— - - - —38cem— — Ps,A = — -3bem— ~ Text-fig. 1—Section of the coil former. H,, H, form a pair of Helmholtz coils which produce an alternating average magnetic field of 88 oersteds per ampere current flowing through them. This field is nearly uniform over the area occupied by the specimen. The dimensions and other details of the coils are summarized in Table I. TABLE 1, Inner diameter of all coils= 4-2 cms. Outside diameter of H,, H,=12-6 ems. Length in Number of | Wire. Resistance Coil. | Centimetres. | Turns. | S.W.G. No. | in Obms. | | | | a | s E | | Hants | 2-9 | 857 | 20 En. 8.C.C. | li Pe 3:8 1835 | 40 D.C.C. 370 lens 3°8 1968 | 40 D.C.C. 400 PS 3°8 1805 | 40 D.C.C. 350 Text-fig. 2.—Schematic diagram of associated circuit. MAGNETIC PROPERTIES OF ROCKS. 39 Associated Cireuit. Text-figure 2 shows the scheme and details of the electrical connections of the associated circuit. The Helmholtz field coils H,, H, are connected in series with a resistance h and a power source 8S. Potential tapped from F is fed to the horizontal deflecting plates or X-plates of the cathode-ray oscillograph (C.R.O.). The pick-up coils P,, P, and P, are connected in series opposition, the unbalanced pick-up being further reduced by an auxiliary coil A and a potentio- meter P. Voltage from these pick-up coils is fed into an integrating circuit, J, the integrated output voltage from which is applied to the vertical deflecting plates or the Y-plates. Field Produced by the Helmholtz Coils. Actual field produced by the coil system has been determined by three different methods : (i) By the use of a fluxmeter. (ii) Passing an alternating current and measuring the pick-up voltage, after feeding it to an amplifier through a 1000 to 1 transfor mer, by a vacuum-tube voltmeter. (iii) Sending a direct current and determining the induced voltage. Typical values (88-07, 88-14, 87-9 and 88-0 oersteds per ampere current), obtained from different methods, showed fair agreement among themselves. Throughout the present work a value of 88-0 oersteds per ampere current is adopted for the field produced by the Helmholtz coils. Balancing of Pick-up Coils. To start with, the pick-up coils P,, P, and P, are wound with nearly the same number of turns on each. | aL | Basalt. Bowely Estate. 36 | Oligoclase basalt. Cement Works Township. 42 | Olivine basalt. Government House, Moss Vale. 44 | Labradorite basalt. ““Summerlees ’’, Moss Vale. 45 | Porphyritic basalt. Blake’s Hill. 50 | Basalt. Belanglo. 75. | Basalt | Allambie 1 alee | M Dolerite. | Mittagong. GS Syenite. | Mt. Gibraltar. MAGNETIC PROPERTIES OF ROCKS. TaBLe II. Susceptibility. Specimen Density, e yx 108 for H (Oersteds). No. gms./cc.) = 176 132 | 88 44 1 2-79 100; fia4 120 130 200 2 2-66 2190 2250 2400 3800 3 2 -62 650 690 800 1200 4 2-78 3740 4000 4400 6500 5 2 -67 2000 2000 2200 3280 1M 2 -82 1790 1750 1720 2600 2M 2-92 6120 6120 6120 6530 3M 2-68 190 140 160 320 4M 3-05 580 620 750 1290 5M 2 90 2000 2060 2240 3200 hi P 2-98 5420 —— -- — 12P 2 +85 8180 8360 8730 12,450 3B 2-95 5200 = 5200 6680 TaBLeE III. Susceptibility. Specimen Density, ¢ yx 10° for H (Oersteds). No. (gms./cc.) - 176 132 88 44 VP 2 +84 1680 1900 2000 3000 2;P 2-81 430 540 790 1000 Sue 2-40 90 80 — — 4P 3-00 3500 2850 3500 4600 bay? 2 +58 1500 1500 2700 2400 @ 12 2-87 4060 4360 4560 6300 gf Lee 2 89 2220 2360 2560 3900 8P 2-88 6900 6800 7300 9800 1 2 -82 3600 3000 ° 3800 9400 10 P 2:78 3500 3550 3600 4140 TaBLeE LV. Susceptibility. Specimen Density, 9° yx 10° for H (Oersteds). No. (gms./ec.) 176 132 88 ft 1S 2-91 3900 4500 5150 7700 12 2-95 3800 4300 5000 7250 17 DOs 4600 5200 5900 8400 21 3-02 3100 3400 3600 5000 32 2-88 4500 4800 4800 6300 34 3-00 6300 6500 6700 9000 36 2°72 7300 7800 8700 13,250 42 3-01 450 450 500 950 44 3-04 3650 4050 4600 6700 45 2-94 6600 6900 7200 10,350 50 2 -90 400 400 450 800 75 2-81 400 400 500 1000 76 2 -90 700 700 900 1650 M 2-76 3450 3500 3800 5500 GS 2 +54 2400 2300 2400 3550 44 NARAIN AND RAO. By obtaining the hysteresis curves for four values of maximum magnetizing field, viz. 176, 132, 88 and 44 oersteds, and determining the densities of the rocks, the variation of specific susceptibility with magnetic field is studied for the specimens in the three groups. These results are summarized in Tables IT, III and IV. Values of the specific susceptibility at the maximum and minimum magnetizing fields along with those of the coercivity (H.) and remanence at the maximum energizing field for all the specimens under investigation are sum- marized in Table Vv. TABLE V. Susceptibility. Specimen y 10° for H (Oersteds). Coercivity, Remanence, No. = He. Tx 108: 176 44 (Oersteds.) 1 100 200 51 38 2 2190 2250 31 25 3 650 1200 26 32 4 3740 6500 23 103 5 2000 3280 26 82 1M 1790 2600 51 119 2M 6120 6530 41 — 3M 190 320 62 30 4M 580 1290 46 107 5M 2000 3200 72 113 ie 9420 — 68 395 12P 8180 12,450 52 257 3B 5200 6680 65 360 ie. 1680 3000 55 94 2a 430 1000 46 25 3P 90 — — — 4P 3500 4600 66 223 5.P 1500 2400 43 63 6P 4060 6300 52 318 ae 2220 3900 43 107 8P 6900 9800 52 189 9°P 3600 9400 58 205 10P 3500 5140 58 376 1K 3900 4500 69 223 12 3800 7250 54 240 17 4600 8400 58 290 21 3100 5000 56 188 32 4500 6300 70 342 34 6300 9000 58 308 36 7300 13,250 47 218 42 450 950 43 25 44 3650 6700 44 189 45 6600 | 10,350 54 291 50 400 800 35 13 75 400 1000 39 19 76 700 1650 47 32 M 3450 5500 38 107 GS 2400 3550 39 75 Table VI shows the y-values at maximum and minimum magnetic fields along with the magnetite contents obtained as q,,,, the normative amount from the chemical analyses, and M,,,, the amount calculated from the modal analyses on thin sections. The values in the fifth column were calculated from v= © x ut where a value of 5-2 for 9,,—the density of magnetite—is assumed. MAGNETIC PROPERTIES OF ROCKS. 45 TaBLeE VI. x x 10° for H Specimen (Oersteds). No. ’ Mixer. = v. ; mt Mt id ie 7m ae 1M 4-64 2-94 2-80 2-49 1790 2600 4550 2M 3-62 7-13 2 -84 1-98 6120 6530 5400 3M 4-4] 6 +65 2 +82 2 +39 190 320) — 4M 3:48 2-44 3-09 2-07 580 1290 — 5M 10-14 6 -62 3-03 5-91 2000 3200 2450 1 6-03 2-48 2-84 3°29 100 200 = 2 3-48 1-49 2-74 1-84 2190 | 2250 3750 3 1-16 0-50 2 -66 0-59 650 1200 2200 4 4-18 1 -82 2 -82 2 -26 3740 6500 5100 5 2-78 0-63 2-70 1-45 2000 3280 3750 11P 32D 4-89 2-98 1-87 5420 = = Ze 9 -28 10-57 2-99 5 -34 8180 12,450 7500 3B 4°87 3:95 2 -93 2-75 5200 6680 4350 The y-values at a low field of 8-8 oersteds calculated for certain specimens by direct measurement of the vertical deflections, are also included in the above table. They serve to show the tendency of the (y—#H) curves with a decreasing field. These values denoted by 7, the susceptibility at H=176 denoted by Xm; the rate of increase of susceptibility given by R —Xm—Xo and the corres- Xo ponding coercivity H. values at the maximum energizing field are shown in Table VII. TasBie VII. Specimen He. No. Xm X 108. Sow Los: it < L083: (Oersteds). 2M 6120 5400 133 41 12P 8180 7500 91 52 3B 5200 4350. 195 65 8P 6900 640 78 52 45 6600 5800 138 54 34 6300 . 4750 326 58 DISCUSSION OF RESULTS. It must be emphasized, in the first place, that all results of hysteretic characteristics of rocks reported in this investigation are obtained at fields far above that of the earth. Obviously, the values quoted do not represent the natural values for the specimens. But as the experiments were conducted under similar standard conditions, the results have significance for comparison among themselves and also have an order-of-the-magnitude significance for their application to the field magnetometric studies. The results of calibration, by replacing the rock specimen by an equivalent magnetic shell, showed a fair degree of repeatability as far as the deflections on the vertical plates of the oscillograph were concerned. A considerable amount of sensitivity is lost by the introduction of the integrating circuit as also a shunt-resistance at the Y-input terminals to eliminate the interference of harmonics on the /—H curve. However, the method of calibration with a 46 NARAIN AND RAO. search coil was found to be quite dependable and has an added advantage of easy operation. A wide range of deflections could be calibrated by winding the coil with suitably thick wires. In the present studies, however, only two ranges of vertical amplification, viz. the 1-0 mV. and 3-0 mV. ranges, were calibrated as the deflections of all the specimens studied lay in these ranges. t//,000 20 40 60 gO 700 120 (40 460 780 Text-fig. 9.—Variation of specifie susceptibility with magnetic field from 44 to 176 oersteds. As is seen from Text-figures 3 to 8, the hysteresis loops are those of unsaturated specimens. On the assumption that the rock specimens contain disseminated spherical particles of magnetite, if can be shown theoretically that a magnetic field of about 2200 oersteds would be required for saturation MAGNETIC PROPERTIES OF ROCKS. 47 of rocks. In loops of some specimens, a tendency to assume a rectangular shape or a flattening at the tips of the /—H curves could be visualized. This shape is more attributable to the small grain size of the ferromagnetic minerals contained in the rock than the magnetic field approaching anywhere near the saturation field. The hysteresis phenomenon is very well marked in all the specimens and, as is shown later, follows the general trend of that of ferro- magnetic minerals contained in the rock, especially that of magnetite. Further, the change of shape of the hysteresis loop with changes in the magnetizing field as obtained in these investigations alse resembles that of ferromagnetic materials, and thereby proves that this behaviour is due to ferromagnetic minerals contained in the rock. H 20000 20 40 6O oO 700 120 740 160 4 4 4 a ———— 1 — 4 Text-fig. 10.—Variation of specific susceptibility with magnetic field from 0 to 176 oersteds. Tables II, III and IV summarize results of variation of the specific suscepti- bility with the magnetic field for all specimens under the three groups ; while Text-figure 9 depicts the same for a few selected samples. In spite of such a large variation among the same group of rocks, it is evident that most rocks have the same trend of variation qualitatively. Specific susceptibility increases in the same manner for most rocks, when the magnetic field is reduced from 48 NARAIN AND RAO. 176 to 44 oersteds. However, the rate of increase seems to differ considerably from specimen to specimen. In the two specimens 12 P and 1, for example, the variations in susceptibility in the field range of 176 to 44 oersteds are 4000 and 100 x10~-* ¢.g.s. respectively. The quantum of change in susceptibility seems to agree well with the content of magnetic minerals of the rock ; the more the magnetic material, the more the change, and vice versa. As mentioned earlier, the specific susceptibilities for a few specimens at a field of 8-8 oersteds were calculated. Text-figure 10 shows the plots of these results, together with the variation of susceptibility over the rest of the field range. The dotted lines indicate the extrapolated probable path of variation of susceptibility between 0 and 44 oersteds. It is obvious from the extra- polation that unless more data are available between 8-8 and 44 oersteds, it would not be possible definitely to locate a sharp maximum of susceptibility. However, the variations in specimens follow the same general trend, viz. an increase of susceptibility up to a field, say, of 30 to 50 oersteds, then decrease of susceptibility with further increase in magnetic field. The latter decrease is rather sharp in the initial stages, usually up to a field value of 80-100 oersteds, and then gradually becomes less with increasing fields. This type of variation bears a close resemblance to the variation of susceptibility of magnetite itself. These results confirm the observations of Takagi (1913) that the y—H curve is “ very similar to that of ferromagnetic bodies, ‘with a quantitative difference that the field of maximum susceptibility is here much larger ”’ 40 1 an fe) /400 Text-fig. 11.—Variation of remanence with rate of increase of susceptibility. Table V shows the range of susceptibility giving the two values at maximum and minimum fields, as also the coercivity and remanence values at the minimum magnetic field. The magnitude of an enormous range of values obtainable with rock specimens is evident in this summary. Coercivity values range from 35 to 70 oersteds, while the average for most rocks may be said to lie between 45 and 50 oersteds. Most of the rock specimens are, therefore, magnetically “soft ’, as has been observed by Nagata (1943), with their coercivities lying below 100 oersteds. From the results tabulated in Table VII, an idea of the relation between the rate of increase of the susceptibility R and the coercivity H, is obtained. The six specimens, though not numerous enough to enable any reliable conclusions to be dr awn, seem to agree in general with Nagata’s (1953) observation that ‘‘ the rate of increase in magnetic susceptibility with H becomes larger according to the increase of magnetic “har dness’’. In this connection the effect of grain size of the ferromagnetic minerals on the susceptibility and the MAGNETIC PROPERTIES OF ROCKS. 49 coercivity has to be kept in mind and unless the shape and size of this effect on the two parameters involved is really proportionate, nothing more definite could be said about the proportionality than that it is a general trend. Another measure of hardness, as adopted earlier by Nagata, is the ratio of the remanent magnetization to the initial susceptibility, i.e. J,/y). If we plot this against the rate of increase of susceptibility (7 ,,—7o)/Yo, the relation thus obtained needs to be a linear one. In Text-figure 11 are plotted the values of I, x10 taken from Table V as the ordinates and the difference between the susceptibility at maximum field and the initial susceptibility as the abscissae. 176 % «4 10% for H r ve wh 4 Ve Za “ [ he / wi 7 Pad ut Magnetite Content [.7eo ov ee — Text-fig. 12.—Variation of specific susceptibility at 176 oersteds with normative and modal magnetite contents, This is in effect the same as plotting the hardness factor and the rate of increase of susceptibility both multiplied by a factor yo. It is interesting to observe that out of the five specimens plotted nearly four seem to fall well on a straight line graph. But, as already pointed out, even from this linear relationship it may be too much of a generalization to say that the rate of increase of suscepti- bility varies linearly with the hardness factor, because the number of specimens involved is too few. Considerations of the effect of grain size of ferromagnetic minerals in the rock apply equally well in this case also. Variations of specific susceptibility at various fields normative, modal and volume magnetite contents are plotted in Text-figures 12, 13 and 14. In Text- figure 12 are shown the modal and normative magnetite amounts against susceptibility at the maximum field of 176 oersteds ; while in Text-figure 13 the same quantities are plotted against specific susceptibility at a field of 44 50 NARAIN AND RAO. oersteds. It is seen from these two plots that the scattering of points is too large to enable any curve fitting. The lines drawn indicate the mean lines through the origin on the assumption that the largest proportion of the observed susceptibility is due to the presence of magnetite content. In Text-figure 14 the specific susceptibilities at a low field of 8-8 oersteds are plotted against the normative, modal and volume magnetite contents. A comparison of the three figures indicates a decrease in the degree of scattering of the susceptibility as the field is decreased. While realizing that the susceptibility values at earth’s 70,000 ° Fe «My 44 /000 % x/0° for H Magnetite content ro Text-fig. 13.—Variation of specific susceptibility at 44 oersteds with normative and modal magnetite contents. field differ substantially from those at even a field of 8-8 oersteds, an attempt has been made to correlate the normative magnetite content, q,,,, with the susceptibility y ) at 8-8 oersteds. It is seen that both Slichter’s relationship (1929) of y,=0-3 V. and Nagata’s relationship given by equation Yo = (2°43 40°75) x 10-*q,,,, are not really applicable for the susceptibility values quoted here. It is doubtful whether a simple linear equation of the type proposed by either will have a universal prediction value. However, to establish an empirical relationship for these rocks, it is assumed that the spec ‘ific susceptibility at 8-8 oersteds is roughly proportional to the normative amount, q,,,. So we can write down MAA hg Me ee gas ave tas lle St yhel ee = eee (v) where A is a constant given by A Hola I Udy Results of nine samples were utilized to ‘fit into such an equation and a value of MAGNETIC PROPERTIES OF ROCKS. 5] 6-39 x 10-2 for the constant was obtained. The error involved in such a constant is given by ror 0 ee oe vii Error in A= ee DEG, (vii) where r is the difference between the observed value of 7) and the one calculated by utilizing the value of A, mG a is the number of observations. The error in this case worked out to be +2 10-2. Hence the empirical relation may be written as 2 Yo= (6°3942-03) X10-Gagyp vee eee e eee eee (viii) Caleulating the ratios of y9/q,,, and obtaining the mean deviation leads to a constant of 8-3x10-2 for A. 10,000 ov i ee 7 [ © Me L L <0 % Se) o zt « e © g x x Magnetie content ro feet a ee Text-fig. 14.—Variation of specific susceptibility at 8 -8 oersteds with normative, modal and volume magnetite contents. However, it is to be borne in mind that such a relation really oversimplifies the conditions existing in a rock. Apart from magnetite, rocks have generally other magnetic minerals such as ilmenite, or complex solutions of iron oxides. The effect of these is ignored in establishing a relationship of the type described above. Moreover, the magnetic history of the rock, the degree of purity of the magnetite, its grain size and its distribution within ‘the rock specimen itself are factors which play no small part in the susceptibility considerations. Plotting these results on logarithmic scale, though having the advantages of spreading the data more uniformly and avoiding the extreme weighting of the end-points, leads one to believe that an exponential relationship similar to the one suggested by Werner and Mooney would be more applicable. But it may 52 NARAIN AND RAO. be pointed out that in the latter’s results, except for a few cases, the exponential constant factor is nearly unity ; also, the scattering is too large to leave any choice between a linear or an exponential relationship. Any trial at curve fitting in this case would have only an order-of-magnitude significance, and that, too, perhaps for specimens studied in a particular case. Unless exhaustive investigations are made on artificially made samples, in which known quantities of minerals are mixed to simulate as nearly as possible a known rock or rock type, it may really be very difficult to comprehend the various complex factors, which affect direct results on rock samples. In such a set of experiments on artificial samples it would be easier to isolate the individual effects and study their variation. Further, the discrepancies in the relationship between the susceptibility and the magnetite content are due, apart from the inaccuracies of Text-fig. 15.—Variation of remanence with normative magnetite. determination and the variation of susceptibility values among themselves, to a considerable extent to the ambiguity in determining the magnetite content itself. The discrepancy in determinations of the magnetite could be visualized at a glance from Table VI. Text-figure 15 illustrates the variation of remanence with the magnetite content. This figure, again, shows the scattering of values as much as the susceptibility. One is led to believe that the scattering is, perhaps, more due to errors in the evaluation of the magnetite content than in the determination of the hysteretic constants as the errors in the latter, if any, are believed to be rather uniform. However, it is seen that, roughly, there is a linear relationship between the remanence and the normative amount of magnetite. VY) MAGNETIC PROPERTIES OF ROCKS. 5S CONCLUSIONS. Summing up, the results of these investigations may be stated as 1. Variation of specific susceptibility of 38 rock specimens in the magnetic field range of 44 to 176 oersteds is studied. There is a general decrease of susceptibility with increasing field strength, the decrease being steep in the initial stages and then gradually becoming less and less. 2. Values of susceptibility determined for a few specimens at 8-8 oersteds and extrapolated to the value at the next highest field observed, produced a curve, whose shape resembles the y—H curve of magnetite qualitatively. 3. Hysteresis and the change in shape of the hysteresis loops with increasing field strength indicate the ferromagnetic behaviour of the rocks. 4. The coercivity values indicate that most of the rocks are magnetically ‘“‘ soft’; it is shown that measures of hardness given by H. and J,/y, and their relationship with the rate of increase of susceptibility are not very trustworthy. 5. Variation of specific susceptibility with normative magnetite content was studied for 13 samples and attempts are made to establish an empirical relationship between them. It is pointed out that due to the large number of factors affecting the results, and their equally large amount of variation among rocks of the same type, it may be hard to establish a relation which will have universal prediction value. 6. All the above results, though quantitatively hard to analyse and interpret, indicate qualitatively the ferromagnetic behaviour of the rocks, and also that this ferromagnetic behaviour is primarily due to the presence of magnetite in the rock, though other magnetic minerals are also sure to contribute their share to the phenomenon. ACKNOWLEDGMENTS. The authors express their grateful thanks to Professor C. E. Marshall for his keen interest and encouragement throughout the progress of this work. They acknowledge the financial assistance given by the Research Committee of the University of Sydney to procure part of the equipment needed for these investigations. REFERENCES. Barret, W. M., 1932. ‘‘ A Method of Determining Magnetic Susceptibility of Core Samples.” Am. Inst. Min. Met. Eng. Geoph. Prosp., 216. Bruckshaw, J. McG., and Robertson, E. I., 1948. ‘* Measurement of Magnetic Properties of Rocks.” Jour. Sci. Inst., 25, 444-446. Bruckshaw, J. McG., and Rao, B. 8., 1950. ‘‘ Magnetic Hysteresis of Igneous Rocks.” Proc. Phys. Soc., 63B, 931-938. Duffin, R. J., 1946. ‘‘ Measurements of Magnetic Susceptibility with the Hughes Induction Balance.” Terr. Magn. Elec., 51, 419-426. Hallimond, A. F., and Herroun, E. F., 1933. ‘* Laboratory Determinations of the Magnetic Properties of Certain Igneons Rocks.’ Proc. Roy. Soc. Lond., 141A, 302-314. ; Mooney, H. M., 1952. ‘‘ Magnetic Susceptibility Measurements in Minnesota. Part I. Technique of Measurements.’ Geophysics, 17, 531-548. Nagata, T., 1940. ‘‘Some Physical Properties of the Lavas of the Voleanoes Asama and Mihara II; Magnetic Susceptibility.” Bull. Earthquake Res. Inst. Tokyo, 18, 102-134. 1943. ‘The Natural Remanent Magnetism of Voleanic Rocks and Its Relation to Geomagnetic Phenomena.” Bull. Earthquake Res. Inst. Tokyo, 21, 1-197. 1953. ‘‘ Rock Magnetism.’? Tokyo: Maruzen Co. Ltd. Nettleton, L. L., and Elkins, T. A., 1944. ‘* Association of Magnetic and Density Contrasts with Igneous Rock Classifications.”’ Geophysics, 9, 60-78. 54 NARAIN AND RAO. Reich, H., 1941. ‘* Magnetic Properties of Rocks and Ores.” Zeits. Deutsch. Geol. Gesells., 93, 443-455. Rucker, A. W., 1890. ‘‘ On the Relation Between the Magnetic Permeability of Rocks and Regional Magnetic Disturbances.’? Proc. Roy. Soc. Lond., 48A, 505-535. Slichter, L. B., 1929. ‘‘ Certain Aspects of Magnetic Surveying.” Am. Inst. Min. Met. Eng. Geoph. Prosp., 238-260. Takagi, H., 1913. ‘‘On the Susceptibility of Soils and Sands.’ Tohoku Imp. Uni. Sci. Repts., 2, 15-24. Werner, 8., 1945. ‘‘ Determinations of the Magnetic Susceptibility of Ores and Rocks from Swedish Iron Ore Deposits.’’ Sver. Geol. Unders., 39, 1-79. Wilson, E., 1920. ‘‘ The Measurement of Magnetic Susceptibilities of Low Order.” Proc. Roy. Soc. Lond., 96A, 429-455. 1921. ‘‘On the Measurement of Low Magnetic Susceptibility by an Instrument of New Type.” Proc. Roy. Soc. Lond., 98A, 274-284. OCCULTATIONS OBSERVED AT SYDNEY OBSERVATORY DURING 1956. By K. P: Sms, B. Se. (Communicated by the GOVERNMENT ASTRONOMER.) Manuscript received, February 7, 1957. Read, April 3, 1957. 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. The necessary data were taken from the Nautical Almanac for 1956, the Moon’s right ascension and declination (hourly table) and parallax (semi-diurnal table) being interpolated therefrom. No correction was applied to the observed times for personal effect but a correction of —0-00152 hour was applied before entering the ephemeris of the Moon. This corresponds to a correction of —3”-0 to the Moon’s mean longitude. —————————————————— ———————— — ——— ———————————— Ors TABLE I. = ——— - = Serial N.Z.C. | No. No. Mag. | Date. 1 Os | Observer. | | | — | —— — — | — | h mi =s 329 oa 8:6 | April 16 9 49 34-6 S 330 984 | 6-6 | April 16 Ora 09% 5 Ss 331 1381 6°3 | April 19 8 56 05-2 W 332 1429 6-8 June 13 8 40 28-3 W 333 1662 6-5 | June 15 Orie Sat Ss 334 2120 6-8 June 19 | 9 37 17:2 W 335 1968 | 6-9 July 15 | 8 54 11:2 Ww 336 2376 4-6 July 18 Ib 35 59°6 S Sor 2509 6-0 July 19 | ld 56 4525 Ss 338 1809 6-9 August 10 10 09 18-6 R 339 2307 | 4-1 August 14 9 O1 34-0 WwW 340 2310 | 4-6 August 14 9 13 06°] WwW 341 | — 8:4 August 14 | 9 16 47-9 WwW 342 2330 | 6-3 | August 14 | 13.59 58-0 W 343 2445 | 7:4 | August 15) | 9 32 11-4 S 344 2457 6-3 | August 15 | 13 17 30:4 Ww 345 2599 | 6-8 August 16 | 15 52 03-5 Ww 346 3093 | 4-5 August 20 | 9 43 34-2 R 347 2826 | 4-0 Sept. 14 | 12 23 12-6 Ww 348 | 2715 6-5 Nov. iu LOU iis R 349 | 89 6-4 | Dec: 12 | 10 08 10-1 Ss Table I gives the observational material. The serial numbers follow on from those of the previous report (Sims, 1956). The observers were H. W. Wood (W), W. H. Robertson (R) and K. P. Sims (8). In all cases the phase observed was disappearance at the dark limb. Table IT gives the results of the 56 kK. P. SIMS. reductions which were carried out in duplicate. The N.Z.C. numbers given are those of the Catalog of 3539 Zodiacal Stars for the Equinox 1950-0 (Robertson, 1940), as recorded in the Nautical Almanac. TaBLeE II. Coefficient of Serial | Luna- Pp q Pp Pq Q? \o | pAc |] qAca No. tion. | Aa Ad | | | | 329 412 |+ 97 | —23 95 —22 5 |—2-4 |—2-3 |+0-6 | +13-0 | —0-35 330 412 |+100 |} + 6] 100 + 6 0 |+0-7 |/+0-7 0-0 | +13:9 | —0-06 331 412 |+ 93 | +38 86 | +35 | 14 |+0-2 |+0-2 |+0-1 |] +14:7 | +0-05 332 414 /|+ 95] +31 90 +29 10 |—0-8 |—0:8 |—0:2} +14:-8 | —0-04 SRR 414 /|+100 | + 3 | 100 || 0 |—1-1 |—1-1 0-0 | +14:1 | —0:34 334 414 |+ 95 | —30 91 29 | 9 |—0-2 |—0-2 |+0-1 | +12:-4 | +0-50 oD 415 |+ 58 | —8l 34 —47 | 66 |+1-9 |4+1-1.|—1°5 | + 4:7 |"—0-95 336 415 96 | —29 92 28 | 8 |—1-2 |—1-2 |+0-3 | +13-1 | —0-34 387! 415 |+ 84] +54 71 | +45 | 29 |—1-9 |—1-6 |—-0") -E11-5.) -20s56 338 | 416 |-- 98 | — 19"! 196 |—19)) “4. |420-38\--0.3 =O eo al One 339 416 + 62 | +79 38 +49 | 62 lee7 1:1 13 | 9-7 | +0-72 340 416 |+100 |} + 7 |} 100 + 7 | O |—1-8 |—1-8 |—0-1 |] +14:0 | —0:03 341 | 416 /|+ 98 | —20 96 —20 | 4 |+0-5 |+0-5 |—0-1 | +13:3 | —0:-30 342 | 416 /|+ 39 , —92 15 —36 | 85 |+2-0 |+0-8 |—1-8]} + 4:4 | —0-95 343 416 |+ 80] +60 64 +48 36 2-2 1-8 1-3 | +11-3 | +0-58 344 416 |+ 97 | —26 93 —25 i 1:3 1-3 |+0:3 +13-5 | —0-27 345 416 |+ 97 | +26 93 +25 7 1-7 1-6 0-4) +13:2 | +0:-34 346 416 |+ 75.| —66 56 —50 44 |+1-0 |+0-8 |—0-7 | +13-6 | —0-39 347 | 417 /|+ 81] +59 65 +48 35 DD, 1:8 les + 9-7 | +0-73 348 419 83 | —56 69 —46 | 31 |+0-8 |4+0-7 j—0-4 | +12-8 | —0-43 349 420 |+ 97 | +24] 94 +23 6 1-4 1-4 0-3 | +12-3 | +0-55 The stars involved in occultations 329 and 341 were not in the Nautical Almanac list; they are Yale 25 2364 and Yale 1/5 I 6660. The apparent place of 2364 was R.A. 65 22™ 468-83, Dec. +21° 36’ 32”-8, and that of 6660 was R.A. 16 04™ 545-99, Dec. —20° 49’ 29”-7. REFERENCES. Robertson, A. J., 1940. Astronomical Papers of the American Ephemeris, 10, Part II. Sims, K. P., 1956. Tuts Journat, 90,17; Sydney Observatory Papers, No. 25. A POLARITY REVERSAL IN THE TERTIARY VOLCANICS OF THE KURRAJONG-BILPIN DISTRICT, WITH PETROLOGICAL NOTES. By KeitH A. W. CRook. University of New England. Manuscript received, December 10, 1956. Read, April 3, 1957. ABSTRACT. The volcanics occur as dykes, flows and necks of alkali olivine basalt containing titanomagnetite. Microscopic examination indicates the absence of ilmenite. and ulvispinel (2FeO.TiO,). One 80-foot flow gives anomalies to +1046. The Merroo Neck exhibits reversal of polarity, apparently due to reversal of the geomagnetic field, and gives anomalies to —2219 y. INTRODUCTION The Kurrajong-Bilpin district (Text-fig. 1) lies some 50 miles north-west of Sydney, and consists dominantly of Triassic sandstones and shales (see Crook, 1957). Physiographically the area is part of the Blue Mountains Plateau. The Triassic sediments are horizontal, except on the east and west, where the area is bounded by easterly-facing meridional monoclines, the monocline on the east having a major fault—the Kurrajong Fault—parallel to and immediately west of it. The development of these structures post-dates the Tertiary vuleanicity and is generally referred to the Kosciusko epoch in the Plio- Pleistocene. The date of the vuleanicity is thought to be pre-Miocene, since there is no evidence of the ? Miocene laterite surface beneath the basalt flows. Specimen numbers used throughout this paper refer to specimens and slides housed in the Museum at the Department of Geology and Geophysics, University of Sydney. IGNEOUS ACTIVITY. TIntrusives. Several dykes, all deeply weathered, occur in the area (Text-fig. 1). Those in the Bilpin region are apparently related to Mt. Tootie, a basalt-covered peak to the north-west. Most remarkable is the dyke swarm consisting of five dykes, the largest being five feet across. They are surrounded by a wall-like aureole of prismatized sandstone. Powell’s Neck, north of Bilpin (522636 St. Albans), noted by Carne (1908, p. 137), is a circular patch of fresh basalt about half an acre in extent overlooked by cliffs of Hawkesbury Sandstone. The soil-covered margins are marked by fragments of what is probably a weathered metamorphosed shale consisting of a box-work of limonite. It may have been derived from the Burralow Formation below. The Merroo Neck (Willan, 1925), which is the Diamond Hill Neck of Carne (1908, p. 102), is a patch of fresh basalt breccia about an acre in extent, some 34 miles north of Kurrajong (668568 Windsor). At its south-eastern corner are outcrops of a very weathered breccia (Text-fig. 3), probably a remnant of the 58 KEITH A. W. CROOK. shale-rich agglomerate which was associated with the vent. This material is the highest topographically in the intrusion, being on the eastern side of a hill of Ashfield Shale. On the east and north Hawkesbury Sandstone occurs. The Mountain Lagoon is possibly situated on an intrusion. The lagoon itself is known to contain white clay to a depth of 14 feet below the floor (Mr. ae AGOON Vv? QO WHEENY CK. ae LEGEND ROADS TERTIARY VOLCANICS DYKES PROBABLE OYKES MOUNTAIN LAGOON PNECK THE GREEN SCRUB BASALT POWELLS NECK MERROO NECK ric: | KURRAJONG -BILPIN DISTRICT MILES: i B. Boughton, personal communication), but this may have come from the surrounding Ashfield Shales. As the lagoon has been well filled for several years, investigation of it was not possible. Hatrusiwes. Lying to the west of the area examined are the basalt covered peaks of Mounts Caley, Banks, Tomah, Irvine, Wilson and Tootie. A flow, which POLARITY REVERSAL OF THE KURRAJONG-BILPIN DISTRICT. 59 occurs south of Mountain Lagoon (630655 St. Albans), was first noted by David (1902, p. 369) and briefly described by Carne (1908, p. 122), who gave it the name ‘** Mountain Lagoon Neck’. This term is discarded, however, in preference for ‘‘ The Green Serub Basalt”? of Willan (1925), because confusion may well arise with the alleged neck on the site of The Mountain Lagoon. Grady and Hogbin (1926), in discussing the physiography of the district, give a brief description of this basalt and the surrounding rocks. Three spurs trending westward from the high ground east of the Kurrajong Fault are covered by columnar basalt which is lower topographically than the plateau surface east of the fault, and cannot be traced over the fault line. The basalt disappears beneath talus cover as the fault is approached. Ashfield Shale, preserved under the basalt, is exposed between the spurs, but contacts are obscured. PETROLOGY. The various igneous bodies are petrologically similar, and are probably comagmatic. They are all alkali olivine basalts, with the association labradorite, forsteritic olivine, titan-clinopyroxene, iron ore and interstitial analcite. A micrometric analysis (vol. percent.) of GR 98 from The Green Scrub Flow gives & composition fairly typical of these rocks : Titan-clinopyroxene .. 41:7 Analcite ae a (ET Olivine .. is oe OS Iron ore .. ss JO°o Plagioclase a: ste wee RY Alteration products a 0-6 Texturally they tend to be trachytic, and intergranular to sub-ophitic. Phenocrysts of olivine and plagioclase are common, and titan-clinopyroxene phenocrysts occur occasionally in the Merroo Neck. The olivine contains iron ore inclusions and is frequently altered to bowlingite, or occasionally to iddingsite. The plagioclase is usually zoned and frequently corroded. Inclusions of clinopyroxene, which may form a band on the margin of the inner zone, and carbonate cores are found in feldspars from the Green Serub Flow. Feldspars from the Merroo Neck show carbonate and iron ore inclusions, and veins and blobs of bowlingite or iddingsite. The zoning in the feldspar pheno- crysts may be normal or reversed (Merroo Neck). The ground-mass feldspar is also zoned at times (Table 1). TABLE 1. Optical Properties of Plagioclases. (Secmons Cut [| ( (010). ) | A | | Extinction Angle X’ 001 Slide No. | Locality. Habit. - ; == Core. Margin. | | GR 98 Green Scrub. Phenocryst. 300 | ay GR 99 i 53 Ground Mass. —15° 40 GR 100 - s A a 2a" | —3° GR 119 Merroo Neck. Phenocryst. —20° | —24° GR 120 as ke | Pe —20° ca... —25° The titan-clinopyroxene, which is occasionally zoned, is generally in a small euhedra, but it may occur as a felty mass associated with iron ore or as a vermicular corona about quartz xenoliths. In GR 120 the clinopyroxene occurs in clots exhibiting a semi-radial prismatic structure with granular margins. Certain features of each igneous body are unusual, and deser rve comment. The Green Scrub Flow is characterized by frequent quartz xenoliths. These may be composite grains, and show bubble trails and chlorite stringers. Quartz 60 KEITH A. W. CROOK. of this type is typical of the underlying Triassic sandstones. The xenoliths are always margined by a corona of vermicular clinopyroxene which represents ‘seeding’ of the magma by quartz. This relationship is similar to that discussed by Stevens (1955) from the Tertiary volcanics of the Southern Highlands. The Merroo Neck contains fragments of a pilotaxitic olivine basalt quite unlike anything encountered elsewhere in the area, and fragments of picrite. The latter contains about 40°% of colourless clinopyroxene, 30% of olivine and minor plagioclase, which is similar to the types found as phenocrysts. Powell’s Neck is unusual in that it contains xenocrysts about 1mm. in diameter of picotite, which is greenish brown with an opaque margin, and of very dark red, almost opaque chromite. An almost resorbed feldspar, with a corona of acicular clinopyroxene, suggests that xenocrysts of calcic plagioclase may also have been present. TRON ORES. The iron ore is without surface alteration. That from the Green Scrub Flow is of late crystallization, occurring interstitial to the feldspar, and usually to the pyroxene. Crystals may be equant and angular (0-1 mm. diameter), due to surrounding silicates ; acicular (0-01 by 0-15 mm.) ; or skeletal (0-1 mm. diameter). Some of. the skeletal crystals are text-book examples. The iron ore in the Merroo Neck, again of late crystallization, is variable in habit. In the typical basalt it occurs exclusively as interstitial equant euhedra 0-02-0:03 mm. in diameter. The pilotaxitic basalt possesses a few large anhedral grains 1-0 by 0-5mm. The remainder is interstitial to the feldspar as before, some as grains 0-02-0-03 in diameter, but most as a ‘ dust ”’ of grains 0-005 mm. or less in diameter. In polished section iron ore and a few grains of chalcopyrite are visible. The iron ore is grey, with a brownish tint, and is isotropic or rarely faintly anisotropic. These properties, allied with the absence, after etching with HF, of exsolution lamelle or ‘‘ cloth texture ” of exsolved ulvéspinel, suggest titano- magnetite, the weak anisotropism being due to lattice distortion resulting from Fe,0, -FeTiO, solid solutions (Hdwards, 1954, p. 76). Ilmenite and ulvéspinel were not detected on microscopic examination. Data on the iron oxide species in alkaline basalts are limited. Newhouse (1956) found only magnetite and magnetite with exsolved ilmenite in nine nepheline-basalts examined by him. Edwards (1954, p. 77) has stressed the speed at which exsolution of ilmenite can occur; it would seem that rapid cooling of the flows has prevented exsolution of FeTiO,;. In the absence of chemical and X-ray data, further definition of the mineral species and discussion of its magnetic properties is impossible. Comparison of habits suggests that the titanomagnetite crystallized later in the Green Scrub Flow than in the Merroo Neck. In view of their contrasted magnetic anomalies this difference is suggestive, but the connection, if any, is obscure. MAGNETOMETRIC SURVEYS. Tables 2 and 3 set out data obtained from magnetometer traverses over the Green Serub Flow and the Merroo Neck. Text-figures 2-4 illustrate the areal relationships of the anomalies. The Green Scrub Flow gives positive anomalies with an observed maximum of 1046 y. Their distribution (Text-fig. 2) suggests that the mass is a dissected flow. The volume percentage of iron ore (5-5°%) and the thickness, about 80 feet, are sufficient to account for the anomalies. To the east the anomalies decrease due to talus cover. Indentations in the belt are due to the absence of basalt between the spurs. The Kurrajong Fault, which trends almost due north POLARITY REVERSAL OF THE KURRAJONG-BILPIN DISTRICT. TABLE 2. The Green Scrub Basalt Data. | | Mean | Aux. Diurnal | Diff. from Station Time, Scale Reading | Mag. Correction.| Local | Primary No. E.S8.T. Reading. x 307. | Correction. Y: Station, Base. a | i | | 1 1155 30: 921-0 | 684 0 1605-0 0 Base 2 1206 26-15 784-5 684 —7 1461-5 —143-5 3 1214 26-1 783-0 684 —12 1455-0 —150-0 4 1226 40-4 1212-0 684 —19 1877-0 272-0 5 1235 24-45 733°5 684 —25 1392-5 —212-5 6 1248 25-7 771-0 684 33 1422-0 —183-0 1 1258 2-0 960-0 684 —39 1605-0 0 1 1348 32°9 987-0 684 —66 1605-0 ) 9 1357 PHS 713-0 684 —66 1331-0 —274:-0 10 1408 42-75 1282-5 684 —65 1901-5 294-5 ll 1416 40-4 1212-0 684 —65 1831-0 226-0 12 1426 45-95 1378-5 684 —64 1998-5 391-5 13 1441 8-15 244-5 2163 —63 2344-5 739-5 14 1452 0-8 24-0 2163 —63 2124-0 519-0 15 1503 15-1 453-0 2163 —62 2554-0 949-0 16 1511 18-3 | 549-0 2163 —6l 2651-0 1046-0 17 1519 —0:5 —15-0 2163 —61 2087-0 482-0 18 1535 28-35 850-5 684 —60 1474-5 —130-5 19 1544 22-55 676-5 | 684 —60 1300-5 —305-0 20 1556 33-25 DOT 684 —59 1622-5 17-5 21 1602 2045 832-5 684 —59 1457-5 —147-5 1 1632 32-6 978-0 684 —57 1605-0 0 TABLE 3. Merroo Neck Data. Mean | Aux. Diurnal Diff. from Station Time, Scale Reading Mag. Correction.| Local Primary No. E.S.T. Reading. x 30y. | Correction. Y. Station. Base. 3 1100 +1-0 30-0 1380 0 1410-0 0 Base 4 1115 +2-55 16915 1380 —2-0 1454-5 34-5 5 1130 +7-35 257-5 1380 —4-0 1633-5 223-5 6 1205 +5-0 150-0 1380 —9:-0 1521-0 NETS) 7 1215 Oso 27-0 1380 —10-0 1397-0 —13-0 8 1225 +1-7 51-0 1380 —12-0 1419-0 9-0 9 1235 +2-35 70-5 1380 —13-0 1437-5 27-5 10 1245 +5:45 163-5 1380 —14-0 1539-5 129-5 3 1256 +1-55 46-5 1380 —16-5 1410-0 0 11 1315 +25-6 768-0 | —1561 —16-0 —809-0 | —2219-0 12 1330 +39-°65 1189-5 —1561 —15-5 —387-0 —1797-0 13 1345 +14-8 344-0 1380 —15-0 1709-0 299-0 14 1356 +37-55 1126-5 —1020 —14-5 92-0 —1318-0 15 1408 +23-1 693-0 —- —14-0 679-0 —731-0 16 1421 +1-45 43-5 1380 —13°5 1410-0 0 17 1430 +0-75 22°5 1380 —13-0 1389-5 20-5 18 1445 +19-45 583-5 = —12-5 571-0 —829-0 19 1455 —1-3 —39-0 — —12-0 —51-:0 | —1461-0 20 1505 +1:4 42-0 1380 —12-0 1410-0 0 21 1515 +2-85 Tee) Hl) UBIO —11°5 1444-0 34-0 3 1530 +1-35 40-5 1380 —10°5 1410-0 0 62 KEITH A. W. CROOK. through Stn. 21 (—147-5 y), apparently truncates the basalt, since sandstone outcrops prominently east of this point. The localized nature of the anomalies would preclude a feeder situated in the fault plane, and there seems little doubt that the basalt pre-dates the faulting. The Merroo Neck exhibits a most interesting distribution of anomalies (Text-fig. 3), and is of importance in being the first totally reverse polarized intrusion discovered in N.S.W. The anomaly pattern confirms the mass as a neck. The rise of the anomaly curve to the south (Text-fig. 4), coupled with the MAGNETOMETRIC SURVEY OF THE ro2 GREEN SCRUB BASALT. 125 STATIONS O |ISOGAMS Text-fig. 2.—Scale: 7-25 ins.=1 mile. even slope on the north, suggests an induced positive anomaly in the south due to a southward plunge of the neck. The anomaly curve, apart from its reversal, is typical for a neck. The residual intensity of magnetization of specimens from the mass has not been determined, one difficulty being the absence of material which is undoubtedly in situ. Although many fresh boulders are present, soil cover obscures their relationships. The following discussion is therefore somewhat tentative. Discussion. Reversals of polarity have been recorded from both overseas and in Australia, a good summary of the literature being given by Hospers (1953-54). Although published records of reversals in Australia are few, they are known from Queens- POLARITY REVERSAL OF THE KURRAJONG-BILPIN DISTRICT. 63 land, N.S.W., and Tasmania. Jaeger and Joplin (1955) discuss reversals in the Mt. Wellington Sill. Day (in Bruckshaw, 1953) records reversals at Ginginbullen in N.S.W. and Mahmud (1955) records small magnitude reversals over the Savoy Sill in N.S.W. Five possible causes of reversal of polarity have been suggested. Two, invoking internal influences, are (a) the existence in the rock of magnetic iron ores (ferrites) having two sub-lattices which can become polarized in opposite directions, giving reversal under suitable conditions; (b) the occurrence in the rock of two ferrites of widely different Curie Points. If present in sufficient quantity in local aggregates, the magnetization of the substance with the higher Curie Point can induce a reversal of polarity as the other mineral reaches its Curie Point. Either of these two effects may be strengthened by removal of any normally polarized material by subsequent alteration. MAGNE TOMETRIC SURVEY OF THE MERROO NECK. KEY 100 y ia ISOGAMS x Pe a BRECCIA FRESH ° =) a BRECCIA WEATHERED SANDSTONE S.__ BOUNDARY -32! QO STATION Text-fig. 3.—Scale: 10-1 ins.=1 mile. Hospers (1953-54), in dealing with reversals in Iceland, has discussed the internal mechanisms at some length and finds them an inadequate explanation for his observations. Two sub-lattice ferrites are unknown in nature, which renders the first explanation improbable. Vincenz (in Bruckshaw, 1953), in discussing the second explanation, states that concentrations of ferrite of between 40°%-60°% are required to produce the desired magnetic effects. Such concentra- tions are not common in basic intrusions. It therefore seems unlikely that either cause can be invoked to explain the reversal of the Merroo Neck. The remaining three causes invoke external influences. Lightning strike, which may cause anomalies of very great magnitude, is generally very local in 64 KEITH A. W. CROOK. its effect. It is virtually impossible that the anomaly distribution observed can be explained by this mechanism, as the negative anomalies cover too large an area. Bersudsky (1937), in a paper which the author has been unable to examine, suggests induction developed in fissured rocks as the cause of the high negative anomalies associated with the magnetite deposits of the Angara- -Tlim region in the U.S.S.R. It is unlikely that this mechanism is operative in the case of the Merroo Neck. There remains only reversal of the geomagnetic field. This mechanism is invoked by Bruckshaw and Robertson (1949) to explain reversals over dykes in northern England. According to Hospers (1953-54), evidence suggests that 500 } ATWWONY << x ° ie) ie) -1500 -2000 DISTANCE ANOMALIES OVER THE MERROO NECK FIG. Text-fig. 4 reversals occur every quarter to half million years, and have been going on since the Miocene at least. Final judgment on the Merroo Neck must await detailed laboratory studies, but on present indications the last explanation seems most likely. It is interesting that the Green Scrub Flow is normally polarized. If reversal of the geomagnetic field does occur this flow will be of an age different from that of the Neck, although the age difference may not be great. ACKNOWLEDGEMENTS. The author would like to express his thanks to Messrs. B. Hobbs and J. M. Jackson for assistance with field work; Drs. H. Narain, T. G. Vallance and J. F. G. Wilkinson for discussion and criticism ; and Mr. and Mrs. Boughton, of Mountain Lagoon, for hospitality whilst on field work. PB) U ~ POLARITY REVERSAL OF THE KURRAJONG-BILPIN DISTRICT. 6 BIBLIOGRAPHY. Bersudsky, L. D., 1937. ‘‘ The Causes of the Inverse Polarity of the Magnetite Deposits of the Angara-Ilim Region.” Hast Siberian Geol. Trust., Tr. f. 20, 73 pp. (Quoted in Bibliog. and Index of Geol. Exclusive of North America, 1949, 14, 21.) Bruckshaw, J. McG., 1953. ‘‘ Magnetic Properties of Rocks.’ Nature, 171, 500-502. Bruckshaw, J. MeG., and Robertson, E. I., 1949. ‘* The Magnetic Properties of the Tholeiite Dykes of North England.” Mon. Not. Roy. Astr. Soc. Geophys. Supp., 5, 308-320. Carne, J. E., 1908. ‘‘ Geology and Mineral Resources of the Western Coalfield.” Geol. Surv. N.S.W., Mem. 6, 254 pp. Crook, K. A. W., 1957. ‘* The Stratigraphy and Petrology of the Narrabeen Group in the Grose River District.””> THis JouRNAL, 90, 61-79. David, T. W. E., 1902. ‘* An Important Geological Fault at Kurrajong Heights, N. 8. Wales.” THis JOURNAL, 34, 359-370. Edwards, A. B., 1954. ‘‘ Textures of the Ore Minerals’’. 2nd Ed., 242 pp. A.I.M.M., Mel- bourne. Grady, A., and Hogbin, H., 1926. ‘* Mountain Lagoon and the Kurrajong Fault.’ THis JOURNAL, 60, 119-129. Hospers, J., 1953-54. ‘‘ Reversals of the Main Geomagnetic Field.” Proc. Kénig. Ned. Akad. Wet., Ser. B, 56, 467-491; 57, 112-121. Jaeger, J. C., and Joplin, G., 1955. ‘* Rock Magnetism and the Differentiation of Dolerite Sill.”’ Jour. Geol. Soc. Aust., 2, 1-19. Mahmud, 8., 1955. Unpublished M.Sc. Thesis, University of Sydney. Newhouse, W. H., 1936. ‘* Opaque Oxides and Sulphides in Common Igneous Rocks.” Bull. Geol. Soc. Amer., 47, 1-52. Stevens, R., 1955. ‘‘ Quartzite Nenoliths in the Tertiary Magmas of the Southern Highlands, N.S.W.” THis JOURNAL, 88, 89-96. Willan, T. L., 1925. ‘* A Geological Map of the Sydney District.” N.S.W. Dept. Mines, Sydney. CORRECTION. THE STRATIGRAPHY AND PETROLOGY OF THE NARRABEEN GROUP IN THE GROSE RIVER DISTRICT. By K. A. W. Crook. THIS JOURNAL, Vol. 90, Pt. 2, p. 64. The scale in Text-figure 1 should read ‘‘ 1 inch =625 feet ”’, not as shown. AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. SEAMER AND ARUNDEL STS., GLEBE, SYDNEY be Lb, Pied re o - < re 1 i s i a fl 7 t : ont 5 ¥ i 3 4518 eS ; ¥ i ee 4 & z Meld a NOTICE. ‘Tur Royat Socrety 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, it assumed its present title, and was incorporated by Act of the Parliament of New South Wales in 1881. TO AUTHORS. Particulars regarding the preparation of manuscripts of papers for publication in the Society’s Journal are to be found in the “* Guide to Authors’, which is obtainable on appli- cation to the Honorary Secretaries of the Society. CONTENTS VOLUME XCI . 2Part ke | = ANNUAL Report oF COUNCIL = «swe ss Oe s ee BALANCE SHEET = ps Se es a ee < ees a e REPORT OF SHOTION oF GROLOGY .. .. ee se oes : oe OBITUARY 3 Ge aa a ae fc on he os List OF MEMBERS fe SP ae Ae So AAT ge cane ae AWARDS .. & Beas a eee eS oe ee ART. I.—PRESIDENTIAL ADDRESS. F'. D. MeCarthy— Part I.—The Society’s Activities .. .._ ee Part II—Theoretical Considerations of Art. II.—OBSERVATIONS ON LATERITE AND OTHER IRONSTONE Soms IN ee : eo 5 ADs a NORTH QU eaNSEaN: D. G. Simonet . ART. III.—Macneric Pporenitks oF Rocks. ART. [LV.—OcCCULTATIONS Ousenies AT SYDNEY Ossunvarony DURING : 1956. °K Pe Sams cs 2a ee cae 5 Se eee Art. V.—A POLARITY REVERSAL IN THE TERTIARY VoLcanics’ OF THE : _ ~KURRBAJONG-BILPIN DISTRICT, WITH PRTROLOGICAL NOTES. - i: A. We Sa Crook... c ee ee ee ee ee ee ee oe THE AUTHORS OF PAPERS ARE ALONE RESPONSIBLE FOR . THE ce STATEMENTS MADE AND THE OFLNIONS eis eae a SES Australian Aborigmal Art... Nee oe rere oe ee ee ee re H Ne arain and. Y. Blatora | Rao See ee eee i Sais , 7 — » Alin: r* ~ : " ‘ a e 4 . y * j t Vs ; eee Se r- dient. wot we ‘ - JOURNAL AND PROCEEDINGS |, : ~ OFTHE {ae ROYAL SOCIETY OF NEW SOUTH WALES 1957 - Edited by the Honorary Editorial Secretary “che ats \ PUBLISHED BY THE SOCIETY, SCIENOE HOUSE, GLOUCESTER AND ESSEX STREETS SYDNEY ——— BAS ee 2 JSSUED DECHMBER 11, 1957 r Registered at the G.P.0., Sydney, N.S.W., for transmission by post as a periodical. e Rayal Soriety of Hew South Wales OFFICERS FOR 1957-1958 Patrons: His EXCELLENOY THE GOVERNOR-GENERAL OF THE COMMONWEALTH OF AUSTRALIA, Fistp-MarsHat Sim WILLIAM SLIM, G.o.B., G.0.M.G., G.0.V.0., G.B.E., D.S.0., M,C. His. EXCELLENCY THE GOVERNOR or New South WALES, LIEUTENANT-GENBERAL E.W. WOODWARD, ¢.8., 6.B.E., D.S.0. President : F. N. HANLON, 3B:sc, : Vice-Presidents: ~ Rey. T. N. BURKE-GAFFNEY, 8.3. ; F, D. McCARTHY, pip.anthr. H. A. J. DONEGAN, usc. Cc. J. MAGEE, D.Sc.Agr. (Syd.), M.Sc. (Wie. ). Hon. Secretaries : J. L. GRIFFITH, B.A4., M.Sc. | IDA A. BROWNE, psc. _ Hon, Treasurer: F, W. BOOKER, Ph.vD. M.se. Members of Council: G. BOSSON, m:sc. (Lond.). Se PHYLLIS M. ROUNTREE, D.Sc. (Melb. Ve G. W. K. CAVILL, m.sc. (Syd.), Ph.D. _Dip.Bact,, (Lond.). (Liverpool). G. TAYLOR, bisc. B.z. (ated, (Syd.), J. A. DULHUNTY, D.8c. B.A. (Cantab:); F.A.A, A. FLA. HARPER, M.Sc. H. F. WHITWORTH, m.sc. -D. P. MELLOR, D.sc. : | H.W. WOOD, m.se. W. H. G. POGGENDOREF®, B.sc.Agr. JOURNAL AND PROCEEDINGS OF THE ROYAL SOCIETY OF NEW SOUTH WALES VOL. 9| [957 Edited by the Honorary Editorial Secretary PUBLISHED BY THE SOCIETY SCIENCE HOUSE, GLOUCESTER AND ESSEX STREETS, SYDNHY A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT ON THE NEPEAN RIVER, N.S.W. By P. H. WALKER and C. A. HAWKINS. Manuscript received, January 4, 1957. Read, April 3, 1957. ABSTRACT. A succession of eustatic-climatic terraces along the Nepean-Hawkesbury River System show a chronosequence of soils, viz. Lateritic soils, Solodics and Podsolics, Prairie Soils and undifferentiated alluvia. Tentative Pleistocene correlations are made. INTRODUCTION. This study represents a more detailed examination of part of County Cumberland which was previously covered by a broad scale soil survey.* An attempt was made to establish the physiographic and climatic history of the area in relation to soil development. The study was carried out along the Nepean-Hawkesbury Rivert system between Pitt Town and Wallacia, within the Cumberland basin, 30 miles west of Sydney (Text-fig. 1). The floodplain here is the widest depositional zone along the river, approximately 100 square miles in area, and includes the agriculturally important ‘“‘ Hawkesbury River Flats ”’. Supporting data were sought between the Sydney coastline and the western plateau region of the Blue Mountains. PHYSIOGRAPHY. The area lies at the foot of the Blue Mountains; it is enclosed to the north, south and west by raised sandstone plateaux at an elevation of 700 to 2,000 feet above sea level. To the east lies the low undulating shale country of the Cumber- land basin, seldom rising above 300 feet. Within the area, six formations have been defined for the purposes of discussion (Text-fig. 2). The main features of these units and their relationship to each other are discussed below. (1) St. Mary’s Formation. This includes the undulating country around Riverstone, Schofields and St. Mary’s with hills up to 200 ft. above sea level and through which run Eastern, Rope’s and South Creeks. This is an old dissected alluvial formation overlying Wianamatta shale. (2) Londonderry Formation. This formation comprises the ancient deposits of river gravels, sand and boulders running sub-parallel to the present Nepean River in a broad band several miles wide. It is relatively undissected and varies in height from 50 ft. near Pitt Town to 200 ft. at Mt. Pleasant behind Cranebrook. *P. H. Walker, 1956. ‘A Soil Survey of the County of Cumberland, Sydney Region, N.S.W.” N.S.W. Department of Agriculture Soil Survey Publication. + Nepean-Hawkesbury system: south of Richmond the river is called the Nepean, and to the north, the Hawkesbury. 68 WALKER AND HAWKINS. (3a) Clarendon Formation. This is a well-defined series of small remnants, the largest of which forms a semi-circular mass between Hawkesbury College and Rickaby’s Creek. It varies in height from 40 ft. to 80ft. and, although relatively flat, has a minor relief pattern of sand ridges and swamps. Other remnants of this formation are found behind St. Matthew’s Church, Windsor, at Pitt Town village and on the western side of the Nepean at Richmond Bridge. (3b) Cranebrook Formation. Probably contemporaneous with the Clarendon Formation is the 80 ft. terrace between Emu Plains and the Castlereagh neck. The main feature of this terrace is a number of sand-covered, boulder ridges running sub-parallel to the present Nepean course for the most part, but con- verging on the river at the Castlereagh neck. L WISEMANS es ERS FERRY 2 GosFoORD ® aos # law's Al) ~ =) a VEAK MK e AWINDSOR FERRY + @KATOOMBA (| \\\\\ove \\) : PENRITH an A \\ INN Aas 9 WALLACIA SYDNEY N x Zz < w Oo as =z a AK is 1 WOLLONGONG 9 iO MILES Scarce Text-fig. 1—Sketch-map of Nepean-Hawkesbury River System showing area studied. (4) Lowlands Formation. This is a younger terrace adjacent to the present stream course. It is probably a composite depositional unit and varies in height from 60 ft. above sea level on the north side of Castlereagh to 17-20 ft. at Pitt Town Bottoms. It is undissected, up to 1 mile wide, and characteristically has large lagoons parallel to the stream course. (5) Hawkesbury Formation. This is represented by a narrow terrace, diminishing in width from 14 chains at its point of departure at Castlereagh neck to a ledge 2 chains wide at Richmond bridge. (6) The Present River Course. Text-figures 3 and 4 illustrate the relationship of levels to one another and to the stream course. | | | | A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. 69 DETAILED DESCRIPTION OF UNITS. In this section the formations are grouped under three headings, viz. Lateritized, Podzolized and Immature Soil Formations. In addition each period of erosion and deposition or soil development is called a Stage and given a number, 7.e. Stage I, Stage II, etc. (See Table 2). Wx College Xs Text-fig. 2.—Contour map showing the Six Formations studied. Seale: 1”=4 mls. S™=St. Marys. L!= Lowlands. L4 — Londonderry. H = Hawkesbury. C! —Clarendon. Ss= Hawkesbury Sandstone. Cr =Cranebrook. W=Wianamatta Shale. Contours: --+-- 100:--: Roads : Formation boundaries ; —-—-— _—-: Sections in Text-fig. 4: Section a Section 6b 70 WALKER AND HAWKINS. (A) Lateritized Formations. (1) St. Mary’s Formation. The characteristic pattern is one of low hills capped with old alluvium and wide valleys partly filled with heavy, more recent alluvium. lLaterite* remnants are found on the low hills at less than 200 ft. elevation. These are in various states of preservation from complete profiles DUNHEVED 169 100-150 Ss 40-50" d St.MARYS FORMATION ‘ +» SCARP ‘90 20-9 av) LY “ Ss pat TOPPE moo CASTLEREAGH 77 per siores © hie 70 FLAT TOPPED , ‘ / $0 : RICKABYS CK. ; A ae 90 LONDONDERRY FORMATION ———. SAND ANDGES 80 R65’ “a 45/ een » Re RENDON FORMATION Sean Aes ik 20/7 — 60-70 ‘4 Ic 2 = 2 rat, ~ - ve SP aAe (es es 25°30 gag — me LA 20-25' 2 3 tities, FORMATIO 1 smairsaaT at WKESBuURY RIVER “~~ HAWKESBURY FORMATION Text-fig. 3.—A view of the Alluvial Formations of the Nepean-Hawkesbury System. with an indurated ironstone layer to mere remnauts of the mottled or pallid zone. The process of lateritization has penetrated through the alluvium at the surface into the underlying shale often to a depth of 4-6 ft. Where the indurated zone is present, the hills are flat-topped with steep scarps overlooking the valleys. SCALE :- Vert. 2 Lots Hor. 2 67 chns. Upthrust sandstone plateau (a) ¥ St Marys formation 300 ” a on v >» x (6) shale hills Dy a ( 200. Z Cranebrook mies vO yi 3 formation vV x a a x F F 199. z 3 e Rouse Londonderry formation 0) we Hine o/S.L CHAINS: 1273 GO3 oO > ) : 200 (o4 Hawkesbury (b) yin Q formation ay 4 Low! wh F u owlands Ts) f G i 6 100 | a formation ) | . @ Slondonderry Clarendon | Si. formation formation Text-fig. 4.—Cross-section from Rouse Hill to Castlereagh (a) with offset to Richmond (6). rN The type location of this formation is found in a rail-cutting east of St. Mary’s railway station. The depositional record is set out in the stages which are enumerated in the Chronology of Table 2. The section (Text-fig. 5) shows a shallow trough cut into the shale and filled with depositional ironstone, sand and large boulders. Weathering has penetrated through the mixed alluvium and * The definition of ‘‘ laterite’ is that used by Hallsworth and Costin (1953), viz. that the laterite soil profile consists of indurated, mottled and pallid horizons and consequently the presence of one of these horizons suggests that there was an original laterite profile, hence the terms “laterite remnant” and “‘ lateritization ’? are used. | A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. 71 deep into the shale. Close examination reveals at least two depositional phases (a) weakly cemented, pisolitic ironstone gravel for the greater part, lining the bottom of the trough, except on the eastern side, where a single layer of large silicified (‘‘ grey billy ”’) boulders rests directly on the shale together with the ironstone gravel, and (b) above this ironstone a layer, up to 15 ft. thick, of weakly cemented, reticulately mottled, current-bedded sandy alluvium which is overlain by another band of ironstone gravel with silicified boulders also weakly cemented. Finally there is a cemented, mottled red and grey sandy clay capping, which was deposited in Stage IV, subsequently lateritized (Stage V) and now has a Yellow Podzolic soil on it (Stage VIII). The cementation of both the ironstone gravel layers, together with the deep red and white reticulate mottling of the underlying sandy layers, suggests lateritization following deposition. This rail cutting has already been described by Storrier (1951) and Hallsworth and Costin (1953) as a multiple laterite, the two ironstone layers representing successive levels of a fluctuating water table. However, on close examination the following features were observed which support the view that the ironstone gravel layers have been transported : (i) Ironstone pisolites (gravel) are current bedded. (ii) The ironstone layers follow the outline of the bottom of the trough. (iii) Ironstone gravel is not a continuous horizon. 160ft. above sea level Current pele mottled ean Alluvium Cemented at Top) Yellow Podgolic Hae MA atc ae ile TK Current bedded Ironstone Gravel Transported MEISE, ‘SOS... Piet tic SAN Ironstone a | Dihaaseee nie aS “Grey-Billy Boulders aN “00 2 267d relies Sy (= Gees Oo wu D ate sete Pega * POS, 62. 38 Terce Wianamatta Shale deeply weathered , bleached, possibly lateritised RAIL LEVEL pet ere ee rome | Text-fig. 5.—Diagram of St. Marys Rail Cutting showing Lateritized Alluvial Deposits in a trough in Wianamatta Shale. The grey billy boulders mentioned in the above description are silicified and up to 24 inches in diameter. They vary in nature from quartzites to sand- stones and conglomerates, but are all extremely hard and, although relatively unweathered, have a distinct bleached periphery of up to one inch. There is no evidence to suggest that they have been silicified in sitw and their position amongst much finer sediments is anomalous, particularly as the boulders them- selves are of very coarse size with no intermediate or fine grades. It is thought that the boulders came either from a previous laterite landscape (Stage I) or material silicified by proximity to volcanic intrusions. In either case the source of the boulders was quite close to their present position, and they moved downslope by creep or slip into the stream basin at a time when ironstone gravel was being deposited. On both shale and alluvium parent material the soils developed both on the hills and in the valleys throughout this formation are heavily textured and strongly differentiated Red and Yellow Podzolics with concretionary ironstone accumulations in the A, and B horizons. Curiously enough soils on the hilltops are Yellow Podzolics where the parent material is alluvium, whereas on shale parent material the hilltop soil is invariably a Red Podzolic. The occurrence 72 WALKER AND HAWKINS. of such strongly developed soils on both hilltop and valley floor suggests a considerable period of landscape stability (Stage VII). Within the area bounded by St. Mary’s Formation, the Eastern Creek deposits give some link between the dissection of the latest laterite—St. Mary’s and Londonderry (Stage V)—and the present day, and for that reason are discussed here. Around Riverstone, Eastern Creek has four levels of interest (Text-fig. 6) : (1) A deposit of heavy blue-grey and reddish-grey tile-clay which is extremely fine textured and tough. ‘This occurs at 38 ft. above sea level. (2) An upper terrace on the creek at 32 ft. above sea level. (3) A lower terrace at 28 ft. above sea level. (4) The present entrenched stream bed which was estimated to be at 10 ft. or 11 ft. above sea level. The creek bed is cut through Wianamatta shale above which is a layer of weakly cemented ironstone gravel similar to that in the St. Mary’s cutting and believed to be transported. The top of this gravel stands at 21 ft. above sea level in the creek bed and occurs again at this level under the upper terrace, and therefore appears to be a base depositional layer under the terrace system. Above this gravel are fine sandy clays and clay loams. There are two terrace levels, and on these soil development differs. On the upper terrace the soil is a strongly differentiated Yellow Podzolic developed on a sandy clay loam parent material. The profile passes quickly from a loam to a heavy clay and then to a fine sandy clay loam by 84 inches. The A, is strongly bleached and tongues into the B. Ironstone accumulation in the A, is marked but is absent in the B horizon. By contrast, the soil on the lower terrace shows a gradual rise in texture over a distance of 20 inches from loam to sandy clay. There is no development of a bleached horizon and no ironstone concretions in the A, horizon. This changes to another material at 34 inches—possibly the butt of the upper terrace. Slightly above the upper terrace level is a deposit of blue and reddish-grey tile clay. This must have been deposited from very quiet waters and may have been a swamp between the levee shoulder and the adjacent shale hills when the upper terrace was being built. It is not clear whether the terraces are climatic or eustatic ; if eustatic, then they must belong to the latter part of the Pleistocene because of their low level. If they are climatic, two periods of relative aridity are suggested for terrace building since the latest laterite-forming period (see Huntington (1914)). Sequence of Events Shown by the St. Mary’s Formation and Eastern Creek Deposits. Soil formation Laterite on subdued topography under suitable climatic (Stage I). conditions—pre-St. Mary’s. Erosion Landscape instability, climatic and/or tectonic. Dis- (Stages IT, III section of earliest laterite landscape, shallow stream beds and IV). cut ; ironstone gravel from laterite deposited together with sandy alluvium and ‘ grey billy’. Two periods of more active erosion suggested by two ironstone and grey billy layers each followed by finer deposition. Soil formation Mild lateritization in the St. Mary’s rail cutting. (Stage V). Erosion Dissection of laterite, downcutting to much lower base (Stage VI). level, deposition of resulting ironstone gravel in Eastern Creek bed, upper terrace built (32 ft.). A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. 73 Soil formation Strongly differentiated Red and Yellow Podzolics formed (Stage VII). on hill country—Yellow Podzolic on St. Mary’s cutting and on upper Eastern Creek terrace. Erosion and de- Upper terrace truncated, lower Eastern Creek terrace position deposited on top (28 ft.). (Stage XI). Soil formation Weakly differentiated Red Podzolic formed on lower (Stage XII). terrace. Erosion Final stream entrenchment to 11 ft. above sea level. (Stage XIIT). (2) Londonderry Formation. These deposits of sands, gravels and boulders cover a much wider area than is shown as “ old river gravels ” on the geological map of Willan (1925). In the area studied they form a broad band several miles wide running north through Cranebrook, Windsor and Mulgrave in a direction sub-parallel to the present course of the Nepean and Hawkesbury Rivers. From SHALE b 40 CHAINS |< 6 CHAINS—+% g HILLS \ eA \ ‘ y = yurem a DENSE CLAY 38‘ ABOVE SEA LEVEL /Q1,41¢ aN a eee x - HILLS aN NK UPPER TERRACE aes Am. SS aE ENSEN 32‘ ABOVE SEA LEVEL LOWER TERRACE al YELLOW PopzoLIC SOIL WEAKLY Devetopen 28 ABOVE sare Corey SEA LEVEL I (SSW Lh ~ = oar “ase ra = rey ent a « *\ aN \" Why eet eeeeeaAR A 1) = i me ey 2 *’ SBANDY ‘AiLivivea Wet VAAN \\ \ A) ba ae 4 sa Dee Se ye teh Be : TERRACE REMNANT x oR fy ee, PB ecb net S a a8g Oe | * sts IRONSTONE GRAVEL LAVER — ibeshertodaie cert etl | _| = 6 ABOVE SEA LEVEL + A o ABOVE SEA LEVEL ——— WIANAMATTA SHALE = CREEK BED Text-fig. 6.—Block diagram showing Section through Eastern Creek Deposits, Riverstone. Cranebrook they cross the Nepean and proceed up the Lapstone monocline almost to Glenbrook. Similar smaller deposits, no doubt of the same age, are widespread up and down the Nepean-Hawkesbury system. Near Glenbrook these deposits are over 400 ft. above sea level and have obviously been carried up by the folding which was contemporaneous with the Kosciusko uplift. East of the Nepean and south of Windsor they form a relatively undissected block tilted east and north-east. From some 200 ft. elevation at Cranebrook, the Londonderry formation slopes down to 60 ft. 14 miles north of Marsden Park. The whole block is remarkably well preserved and flat topped. It has been cut into by the Nepean on the western side, leaving a steep 30-40 ft. scarp fronting a younger terrace, and on the south-east and east by South Creek forming a similar steep scarp. This is demonstrated in Text-figure 4. A characteristic dense scrubby vegetation with tea-trees (Melaleuca spp.) and ironbark (Hucalyptus crebra) as the larger species distinguishes this tract from the surrounding country. For the greater part of the area a sandy cover obscures the boulders, but wherever this cover has been penetrated a bed of boulders and sand has been found beneath and sometimes another layer of sandy 74 WALKER AND HAWKINS. material occurs under the boulders. The deposits vary in thickness from 13 ft. to 40-50 ft., where observed, and overlie Wianamatta shale throughout the area. As a whole, the area has been only mildly lateritized, probably at the same time as the St. Mary’s Formation, for a crust of ironstone was found at only a few places. Nevertheless the boulders show intense chemical weathering, so that while the exact form of the boulders is preserved they easily crumble to a white powder in the hand. The sedimentary material of this formation consists mainly of large water- worn boulders up to 15 inches in diameter, set in a matrix of sand and sandy clay and, in places, current-bedded ironstone gravel. The boulders are dominantly quartzites and sandstones with some granites and porphyrites. The size of the boulders and depth of the deposits indicate the great power and duration of the streams which deposited them. The orientation of these deposits shows that they were laid down by the ancient Nepean River prior to the uplift of the Blue Mountains plateau in the Kosciusko epoch. The soils developed on the lateritized remnants of this formation are deeply weathered and well differentiated Yellow Podzolics, having deep surface soils and heavy accumulation of concretionary ironstone in the A, horizon. Where part of the indurated horizon of the laterite remains, Red Podzolic soils are developed. There appears to have been little dissection of this formation about Londonderry, so that the soils are very old and show the characteristics of deep chemical weathering. The presence of current-bedded ironstone gravel incorporated in the London- derry sediments near Windsor indicates that existing laterites were dissected during the period of deposition. The sedimentary sequence is similar to that of the St. Mary’s formation and it is suggested that the sedimentation and subsequent lateritization of these two formations was contemporaneous. (B) Podzolized Formations. (3a) Clarendon Formation. The main remnant of this formation, between Hawkesbury College and Rickaby’s Creek, abuts the Londonderry formation but differs from it in that there is no evidence of lateritization. It is mildly undulating with a relief pattern of sand ridges and swamps. The largest sand ridge runs in a general east-west direction through the grounds of Hawkesbury College and rises to 80 ft. above sea level at the western side fronting the Nepean. On the other hand the general terrace level falls to 40 ft. along Rickaby’s Creek. The pattern of sand ridges and swamps, so clearly seen on a detailed contour map, suggests wind distribution of the surface materials in some past period. South of Richmond, at Agnes Banks, Simonett (1950) has described a series of similar sand dunes. An almost perpendicular scarp 30-40 ft. high separates this terrace from the younger one below. Road cuttings through the scarp show at least five layers in this formation ; in particular, the road cutting on the eastern edge of the scarp overlooking Rickaby’s Creek (Text-fig. 7) illustrates this layering. Text-figure 7 shows the following sequence : (1) A surface layer 3-10 ft. thick of loam to clay loam texture which has a strongly differentiated Yellow Podzolic soil developed on it. (2) Remnants of a mottled, drab, compact layer which is light clay in texture, micaceous and sometimes vesicular and about 2-3 ft. thick. It appears to have been partly removed during the laying down of the surface layer. A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. 75 (3) A layer of micaceous, mottled, loose sand 2-4 ft. thick which is not continuous but sometimes occurs in what were depressions in the old surface beneath. Current-bedding is evident in some exposures. (4) A rather dense vesicular layer of fine sandy clay or clay loam which is mottled dark grey and yellowish brown. It has light to moderate amounts of iron oxide deposited in the form of vertical pipes, each with a small hollow down the centre and measuring 2-3 in. long and 3 in. in diameter. The whole layer gives the impression of having been swampy at some period, and usually forms the lowest visible layer in the cutting down to 13-18 ft. In one case a layer of micaceous sand was found beneath this. At least two periods of stability with lengthy periods of exposure are represented here. The first followed the deposition of dense light clay at the bottom of this cutting 10-12 ft. below the surface and was marked by consider- able iron segregation giving abundant tubular ironstone. The second period of stability followed deposition of the surface layer. Between these two periods 65 ft. above sea level Yellow Pod3olic Soil 5 1 a Clay Loom - Scarpface - Compacted So mottled es ge oe EO AG) pit oe Tf - Dense vesicular — mottled clay loam — moderafe iron oxide} _ in the form of pes 14. FT. GINS Es [+6 FT. Covering loose Sand lorem ek sa Text-fig. 7.—Diagram of Road Cutting, Richmond, through Clarendon Formation. | Micaceous alternating fine and coarse deposition took place, but no evidence of prolonged stability was found. On Richmond aerodrome, away from the scarp, pits showed 4—5 ft. of sandy alluvium overlying water-worn boulder beds down to at least 8 ft. This is the only occurrence of boulder beds found on this terrace. The soils developed on the surface layer of sands and light clays are Ground- water Podzols, Red and Yellow Podzolies and Solodics. The Red Podzolics occupy the ridges and the Yellow Podzolics the depressions. The Yellow Podzolics are strongly differentiated with a deep A horizon up to 3 ft. thick and a strongly bleached A,. Heavy ironstone accumulation occurs in the lower part of the A and textural contrast between A and B horizons i en from a loam to a heavy clay. A deep A horizon is a feature of the Red Podzolics also but texture grading is much more gradual here than in the Yellow Podzolics ; bleaching in the A, is absent and only soft concretions of iron-cemented sand are found. The Groundwater Podzols show intense bleaching in the A, and an iron-organic cemented B at 30-36 in. below which is a deep zone of clay accumula- tion. The Solodic soils have a shallow (2 in.), extremely bleached A horizon over a deeply cracked, broadly columnar clay B horizon which has a marked predominance of sodium and magnesium on the exchange complex. A subdivision of the Clarendon formation is possible on the basis of the degree of soil profile differentiation. The older soils are for the most part Yellow Podzolics and Groundwater Podzols, while the younger are predominantly Red Podzolics. The older soils have strongly bleached A, horizons and contrasting 76 WALKER AND HAWKINS. A and B horizon textures in all topographic positions. They are found on the high sand ridge which runs through Hawkesbury Agricultural College and on similar dunes south to Agnes Banks (see Simonett (1950)). The Solodics and Yellow Podzolics on the eastern edge of the College also belong to this sub- division. The younger soils do not have well-developed texture contrast or bleached A, horizons except in local depressions where Yellow Podzolics occur. These are found on the western edge of Hawkesbury College and continue through Richmond to Clarendon. These subdivisions, based on the degree of soil profile development, are similar to those observed for Eastern Creek near Riverstone, and it is probable that the individual terrace systems are related. (3b) Cranebrook Formation. This formation is separated from the Clarendon formation by the Castlereagh neck, and lies at the foot of the Londonderry scarp. The strip of alluvium, 2 miles wide, seems to have been deposited by a progressive lateral shift of the Nepean River bed towards the foot of the Lapstone monocline. The resulting sedimentary pattern consists of a series of boulder ridges running parallel to the present stream. The soils on the ridges are weakly-developed Red Podzolies showing little iron movement and no great textural differentiation. Weakly developed Red Pod3olic Undifferentiated Shale Colluvium Remnant of. : Red Podgolic profile re Yellow Pod oli Sandy Alluvium DRAIN FLOOR a CHAIN —————— Text-fig. 8.—Sketch of Drain Wall, Jamieson Road, Penrith, cut through Cranebrook Formation. In the depressions well-developed Yellow Podzolics are found. The soil pattern is therefore similar to the younger subdivision of the Clarendon formation and there is little doubt that the formations are contemporaneous. South of Penrith an interesting exposure of buried soils was found on the Clarendon terrace close to the flanking shale hills (Text-fig. 8). The oldest layer exposed is a sandy alluvium having a shoulder on the western side and a depression against the shale hills. On the shoulder a Red Podzolic soil was developed with a Yellow Podzolic in the depression. In the depression heavy shale colluvium from the adjacent shale hills overlies the sandy alluvium; on this heavy material a strongly-differentiated Yellow Podzolic was developed. Some sand from the nearby alluvial shoulder has blown over this second layer. Subsequently a further sand layer was deposited on the existing sand rise and from this sand deposit an immature Red Podzolic has been formed. Sequence of Events shown by Clarendon and Cranebrook Deposits. As far as can be determined by field observations, these formations are the next in chronological succession to the Londonderry formation. They represent the first material laid down subsequent to a major shift in the river course to the present river valley. In the literature this shift has been attributed partly A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. 77 to the major uplift of the Western Plateau, said to be part of the Late Pliocene, or Kosciusko uplift. Jensen (1911) suggests that an upbowing of the landscape, due to volcanic activity of similar age to Prospect, was the main cause of the westward shift of the river. The Clarendon and Cranebrook formations are generally at a lower level than the Londonderry and the soils show no evidence of lateritization. The relationship between Clarendon-Cranebrook and Londonderry is similar in most respects to the relationship between the Eastern Creek terraces and the St. Mary’s formation. In each case the older formations have been lateritized and subsequently dissected to varying degrees. On the dissected remnants Red and Yellow Podzolics have formed. On the other hand, the younger terrace formations are not lateritized but do show podzolic soil development and are relatively undissected. The absence of laterite on the younger formations indicates a major climatic change. The suggested sequence of events is: Uplift and Change in New stream course eroded. Nepean Course (Stage VI). Unknown time interval. 2 Depositional period (Stage VII). Stability (Stage VIII). Depositional period (Stage IX). Stability (Stage X). Depositional period (Stage XI). Stability (Stage XII). Deposition (Stage XITT). Stability (Stage XIV). Sand, followed by light clay of Clarendon level laid down. Weathering and soil formation ; older Clarendon soils (iron segregation). Podzolics and Solodies of Hawkesbury College- Agnes Banks. Sand and light clay material, Clarendon and Cranebrook. Soil formation; Groundwater Podzols and Yellow Podzolic on alluvium on Jamieson Rd. (Text-fig. 8). Surface sands and loams of Clarendon. Red and Yellow Podzolics of upper Clarendon and Cranebrook. Jamieson Rd. Yellow Podzolic on colluvium. Red Podzolic on sandy alluvium. Sand of Jamieson Rd. cutting, alluvium against stream. Weakly developed Red Podzolics, Jamieson Rd. (C) Immature Soil Formations. (4) and (5) Lowlands and Hawkesbury Formations. The Lowlands formation is distinguished not only by its level but also by its well-structured Prairie soils. The terrace begins on the north side of the Castlereagh neck at 65 ft. above sea level, but quickly drops to 40 ft. by Agnes Banks. A further drop to 20 ft. opposite Richmond on the north side is followed by a relatively level portion from Richmond to Pitt Town Bottoms, where it stands at 17-20 ft. above sea level (see Text-fig. 3). It is up to 14 miles wide and consists of fine sandy sediments with little or no gravel. At approximately 8 ft. under this terrace the remnants of an older terrace are found—presumably part of the Clarendon formation. 78 WALKER AND HAWKINS. The soils of the Lowlands formation are Prairie soils with deep organic matter penetration, good crumb structure and no texture differentiation. There has been considerable worm activity which has assisted organic matter penetra- tion and destroyed alluvial stratification. The Hawkesbury formation is the latest terrace against the stream course. It consists of mixed stratified sediments made up of sands, boulders, ete. From 48 ft. above sea level at the Castlereagh neck it drops to 8-10 ft. by Windsor. The sediments are strongly stratified, with no organic matter penetration and no evidence of modification due to soil-forming processes. Not only are these two formations separated clearly from Clarendon forma- tion by a steep scarp of 20-40 ft., but there is also a marked difference in soil profile development, denoting a long time interval. t ScALE:- Vert. 2 100 ft Hor. 2 10 Mis. REET MENANGLE + 145’ ; fay 00 7 Zz FF. 1°) ° yo Ze : zs Iw oe, wl + oF | ao a S:k. . ° a ee el ee — MILES 4 so ae 100 140 & - 100 eer om 2; - 200 = -300 AC One ee = Emer <%o = ani oo a Text-fig. 9.—Thalweg of the Nepean-Hawkesbury River Rock Bed. (6) The Present River Course. The Nepean-Hawkesbury River system drains an appreciable portion of the Sydney Region. By far the greatest contri- bution comes from the tributaries to the south-west, which drain the upwarped dividing range running parallel to the coast. The river rises south-west of Sydney ; the main arm, the Wollondilly River, joins the Cox’s and sweeps down in a wide are from the tablelands as the Warragamba River. The Nepean rises south of Picton in country of much milder relief, and is joined by the Warragamba at Wallacia. The combined stream cuts through part of the Lap- stone monoclinal fold and emerges at Penrith to run along the foot of this fold and across the western edge of the Cumberland Basin. At Sackville, north of Pitt Town, it enters the Hornsby plateau, through which it meanders in a deeply incised gorge. At Wiseman’s Ferry the river turns abruptly at right angles and flows east into Broken Bay. The rock floor of the stream is 230 ft. below sea level at Peat’s Ferry bridge, 14 miles from the sea, and rises to sea level between Richmond rail bridge and Castlereagh, 88 miles from the river mouth. The thalweg of the stream (Text-fig. 9), back as far as Menangle on the Nepean, shows at least three kink points. It is not known whether these changes in river grade are products of eustatic fluctuations of the sea or local subsidence. Insufficient data are A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. 79 available to obtain the true gradient of the rock floor between Peat’s Ferry and the ocean and therefore the depth of the submerged trough at the mouth of the river. In the absence of such data it is not possible to correlate the depth of the submerged mouth with past low sea levels. However, drowned river valleys are typical of the eastern Australian coastline, and it seems more logical to propose eustatic movements than regional subsidence. Abundant evidence is available from various parts of the world, particularly in the Pacific Ocean, for sea level changes of the order of 300 ft. during the Pleistocene. [See Zeuner (1945, 1952), Stearns (1938, 1945), Tindale (1947) and Brothers (1954). ] SoME IMPLICATIONS OF THE TERRACE OBSERVATIONS. Laterite is generally accepted as an ancient soil formation in Australia. Some workers [Prescott and Pendleton (1952), Woolnough (1927) and Hallsworth and Costin (1953)] have placed it in the Miocene; others [Whitehouse (1940), Hallsworth and Costin (1952)] regard it as Pliocene. In the area studied evidence was found of two laterite landscapes of different ages—an older pre- St. Mary’s and pre-Londonderry laterite (Stage I) and the younger St. Mary’s and Londonderry laterite of restricted occurrence (Stages II-V). The former supplied the current-bedded ironstone gravel which was re-cemented in the St. Mary’s and Londonderry formations. The second laterite stage was confined to alluvial parent material and hence lateritization must have been restricted to low-lying areas along stream courses in this period. In accordance with previous ideas regarding the age of laterites in Australia, the older or pre-St. Mary’s laterite must be placed as Miocene or at least Pliocene in age, while the younger St. Mary’s and Londonderry laterites would be Pliocene. However, one of the major obstacles to placing these laterites in the Miocene or Pliocene is their height above sea level, particularly when the general proximity of this area to the Pacific Ocean is considered. Several workers (Zeuner, 1945 ; Stearns, 1945 ; and Brothers, 1954) have recorded sea levels as high as 550-600 ft. above the present for the Pacific Ocean and have suggested their age as the beginning of the Pleistocene. Evidence from Europe and America further suggests that Pliocene and Miocene sea levels would have been at least as high as this, and possibly higher. Such sea levels would have inundated the whole of the Cumberland Basin up to some 300 ft. above the present levels of the St. Mary’s and Londonderry laterite formations. No evidence has so far been found of such widespread drowning. This leaves two possible alternatives : (1) Subsidence since Pliocene times has affected the whole of the Cumberland Basin, reducing its level by at least 300 ft. to bring these laterites to their present low level. (2) Subsidence in the areas concerned has been slight or absent, so that the laterites were formed well into the Pleistocene, by which time the Pacific Ocean had progressively dropped to about 150 ft. above its present level. On the assumption that these formations are Pleistocene it is possible to correlate all the alluvial formations with known past levels of the Pacific Ocean (see Table 1). The consequence of this alternative is that the Kosciusko uplift post-dated the mid-Pleistocene since parts of the Londonderry formation, at 110-150 ft., or mid-Pleistocene level, were carried up the monocline. If the first alternative is accepted, the present Londonderry and St. Mary’s and probably the younger landscape elevations cannot be correlated with past sea levels, and the depositional chronology will be complex. 80 WALKER AND HAWKINS. Examination of the higher reaches of the Nepean River reveals that the Clarendon formation occurs at higher levels than between Richmond and Windsor and may be as high as 150 ft. above sea level in the vicinity of Wallacia. This results in a steeper gradient upstream from Richmond than between Richmond and Pitt Town, indicating that the upper part is of climatic origin while the downstream end, where the river bed is below sea level, has been affected by eustatic changes. Similar terrace gradients have been found for the Londonderry, Lowlands and Hawkesbury formations, indicating that they too could have been the product of the dual influence of climate and sea level. It would be expected that climatic terraces would have been built during warm- dry interglacials and interstadials, when the landscape was unstable through reduced vegetative cover, at times of high sea level. The gradient of these TABLE 1. Comparison of Hustatic Levels of the Pacific. Pacific Is. New Zealand. Australia. Stearns Brothers Tindale Nepean-Hawkesbury System. (1945). (1954). (1947). Feet. Feet. Feet. St. Mary’s and Londonderry : 110-150 feet Ss aK ae a5 +150 +110-130 150 —300 feet .. Sf ae ae sv —300 ? ? she ee - He 5 +100 ? 105-110 Clarendon and Cranebrook : -+40-80 feet ree ae ne aie + 70 + 45-— 75 65 + 45 | ? Se ae hr ate “a — 60 ? Lowlands : | | +15-20 feet ay. 2p ie be; SOT +, 15— 25 (29 25 2) ? me és ae Me ue ? | —190 Hawkesbury : +8-10 feet.. ae ks uy ee + 5 + 8 12 5-10 climatic terraces would be roughly parallel to the stream bed, to a point where inundation of the lower stream course by higher sea level would cause the terrace gradient to flatten, giving a eustatic terrace. This in fact is the typical structure of the Nepean-Hawkesbury terrace systems. Text-fig. 3 illustrates that in the Richmond-Pitt Town area younger forma- tions occur below older formations. This could be explained as a result of intermittent uplift in the area, assuming static sea level. However, from Richmond to Broken Bay the rock bed of the river falls from sea level to —250 ft. at least, and if this were the result of subsidence, then uplift is precluded. Subsidence, on the other hand, would result in younger terraces occurring above the older, whereas at Richmond the reverse is true. Another explanation of the terrace sequence is that it is purely climatic. This does not afford an explanation of the deep entrenchment of the lower stream course. Furthermore, it is unlikely that the terraces between Richmond and Pitt Town would have been beyond the influence of the high Pleistocene sea levels since nowhere do they rise above 90 ft. The general succession of terrace levels between Richmond and Pitt Town, the deep entrenchment of the stream bed and the presence of kink points along its lower course can be best explained as due to progressive sea level fall with the A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. 81 superimposed fluctuations caused by glaciations during the Pleistocene. The upstream extensions of these terraces south of Richmond are due to climatic influence. CHRONOLOGY. It will be noticed in Table 2 that there are two very long periods of erosion. The first occurs between the St. Mary’s and Clarendon formations, where the height difference is considerable (100 ft. at Riverstone and 50 ft. at Cranebrook), and during which there was a change from the laterite type of soil weathering to a milder type giving podzolic soils only. The second is that between the . Clarendon and Lowlands formations, where the height difference (20-40 ft.) is again marked and the soil differences are great on the same type of parent material. The soil chronosequence may be summarized thus : (a) St. Mary’s and Londonderry Formations: Lateritic soils formed at high levels (110-150 ft.). (b) Clarendon and Cranebrook Formations: (i) Dominantly Yellow Podzolic soils formed on terraces at 40-80ft. (ii) Dominantly Red Podzolic soils formed on terraces at 40-80 ft. (c) Lowlands Formation: Prairie soils formed on terraces at 30 ft. (d) Hawkesbury Formation: Undifferentiated alluvial deposits as terraces at 5-8 ft. Correlation of the terrace levels with past sea levels can only be very tentative in the absence of more data. In Table 2 an attempt has been made to relate data from the various formations and correlate these with sea levels of the past. It is important to emphasize that whether or not the following correlations are valid, the relative chronology, as outlined, is of primary importance. It ean be stated that from St. Mary’s to Hawkesbury time there have been periods of vigorous stream cutting alternating with periods of aggradation and terrace building, and that these periods can be readily differentiated by a study of soils and landscape. Furthermore, such studies show beyond doubt that this is an extended time sequence covering a significant part of the geological past, and has particular bearing on Pleistocene pedological history. SUMMARY. A study was made of river terraces and associated landscape along part of the Nepean-Hawkesbury system. Six physiographic units were defined, repre- senting successive stages of alluvial deposition and soil development. Pro- ceeding from the older to the younger, these were: (A) Lateritized Formations. 1. St. Mary’s .. Undulating country with some remnants of lateritized alluvium; Red and Yellow Podzolic soils at the surface. 2. Londonderry Undissected river sands and gravels, lateritized ; Yellow Podzolics at the surface. (B) Podzolized Formations. 3a. Clarendon and Undissected river terraces ; soils of varying ages at 3b. Cranebrook. surface including Ground Water Podzols, Red and Yellow Podzolics and Solodies. (C) Immature Soil Formations. 4. Lowlands .. Undissected river terrace ; Prairie soils at surface. 5. Hawkesbury — River terrace ; stratified, undifferentiated sediments. 6. Present Nepean-Hawkesbury course. WALKER AND HAWKINS. 82 “uory -eulIoy §,AIVW “4S uo o1ozpod MOTIAA “yoo Uloyseg jo soozpog seddn ayy pue syurg sousy ‘eseT[op Anq *y90I9 -SOYMEH JO Soljoz UloysVay yoddn -pod pue sorpojos pue yooirqeuely {(uo]yeBoises UOT) é | ‘wopterey) Apreg, é ‘Joos “4stoy | S[fos Wopuerv[D TePlO “APTLY IIIA “Yoo U1oysey jo syueurrpes soddn *yooIp {ssurgyno prod uloysey goddn yoorqouriy pure pue yoorqouriy uopusie}g jo sAvyo “od ‘uopuele{pD AUIV fh é pue spurs ysomoT | UoryIsodep pue UOolsory IIA “80911048 ‘yoo Ul04yseq sg, AI’ “98 JO Worqoos OAvIs QuOysUOIT | -SIP + WOISOLO aAT}OV "sy UOUWIIpes ¢asammoo JoATyY UeedeN ‘WGL-OF [PAI] BOS *yoomqouri) *(surTaqs yoorqeuvdy pure ul esueyo * neoyeld [epovpsIojUy WINAM-ssIyY | PUB TOpUsIVI)D Ayem | -410) 9u9004S19[d_ é uopuele[p) yomoT | urojsom jo yida IA “80411048 *£IIOpuopuoT AIIIpuopuoyT “UOTYRZI4L 6 | puv s,Arv “4S 0}eT *aus00![d ‘ayereduie} “4sloyy | pue s Are 4S -IoyR] plu + AWWPAVIS A *AIJopuopuo'T osje §=‘s,Arveyt “98 ‘od ‘od ‘od ‘od *snqliyop O}IIO}V'T ‘UOISOIa PesvaIOUT AL *(JQA0L BAS “93 OGT-OOT) *AIJopuopuoT “sy UOUIIpEs [eLovpsioyUY SsTY-[EPUL | Pue s,ATeTV “4S ATIVT *9U900T[ qd -9UIDOTPL ‘od sAreW 9S = OU ‘UOISOI BATJOV SSO'T Til ESS “Sa ‘AlJopuopuoT jo *(JaA0T BAS “45 OST-OOT) *£IIapuopuoT qived =pue s,AIeyr ‘aqtoye, JO WOTzeSSIp jefor[s10yUT ssiy-[Epul, | pur s,ArTey “9S AYIVL *9U9001[ q-aUI90TIL 4 yeordory, “49 ‘Snylyop a}loyvT | + UOTSOIa 9ATIOV AIOA I *So}lIO}e] yIvd [VuolyeNn *AIJopuopuoT pue AqsuloyR “UOTPVZIFLI9}VT ISTO} 4 | -oid ‘s,AleW “4S9-d “QuUs00I *yeotdory, | ‘o}1104e] peoldsoplIM -ut ‘ advospury 9[qe4S i ee ee — *SUOT}RIAIION [9Ad'T *AINQsoyMe A “(g¢61) UIySs0D Bag us004S10[q -uvadoN pue yyomMs][eH (g) (3) (T) “suOlgIpuoo O1yRUly[o “1108 “UO]}RJUIUIT PIS ‘advospuvT JO 2984S ‘O8BIg poqsedang “sogpeog UTE sAtzequay, *ABojouoLy ‘SZ QIAV.L 83 A STUDY OF RIVER TERRACES AND SOIL DEVELOPMENT. “UO1} BULIOS AIUqsoyMe jo sjeaein pue spurs “‘quosolg *‘Jajoo) “ysloyWT | pogeiqguetoyiIpuy “AYTTIGVIS JAX “u0ly -vUlIoy AINGSOYM AL “YF OI-E QUAY aeT | ‘AImnqsoymeR ApIeq *AIp ‘WIBAL JO SJaAvIs puv spuvg | ‘uorysodep pur UOIsoIgy AX “‘spuv[MoT Jo s[los oleig * ‘pw uosoruep = ‘tWealys 4SUIVSR S]IOS OLITelg pue solozpog per “SpUuR[MOT 9048'T *Jajooo “ystoyy | pedopaasp ATYVOAA “AqTqRIS AIX “UOIPVULLOF spuv[ MOT : PU uosaluee = UI ea4s qsurese = WIN TAN]]e SUIvIpP "PY Uosarture fc “YJ OZ-ST JUdD0y ApIe ‘spue[MoTyT Ape “AIP ‘WIG M jo spurs qysoultoddy | “uorsodep pur uojsorg Tx “UMIANT[? UO oozpog ped (8 "py uosorure se “BY-} xo) UNTANT[IOO uo oTOzpod AMOT[AA *S]IOS Yoo Uloyseg IdMOT Ssytsod -ap yoorqouedy pure uopudirz[p 9Q0VJAMS JO SoOZpoO “(g) TeoepTD WIN AA “UOpusale[) 93v'T *Jooo “4sIoyy | MOTTPA pues poy “AVTTEQRVIS IX “a0VI ‘spsodep yoorp -I0} YooIQ Uloyseq ulojseq JaIMOoy "3 GL-OF IIMOT | YOOIqoueID SUOPUdIR[D JO SULBOT [eloe[sIojUy UN AQ-ssiy | pue UOpuare[D 99e'T é ‘AIP ‘WIIG pue spurs oovjing | ‘uorIsodep puv uolsoig, 1B'¢ “PY Uosouwe ¢* WMIAnTe UO oOZ -pod MOT[AA + ase] “95 GL—-OF “9Ua004SI9[ qd. [Og AINGsoyMeV]T JO TePoerps10,UT WIN AA -ssty “UOpUale[O-PI, | ‘suleysyIo0 = WapuleD *Jooo “4stoy | sfozpod JoyemMpunoly “AUTTIGRIS axe 8 "BY-9X0L, — ‘py uosomes UINIATT[® JSAMOT 2 “DY-yxXo., — 5uryyno “yoorqouriy peor uopusielyD 4 | pue wuopudsle[o-pI é “AIP ‘ULIV A jo sAvjo pue spueg | ‘uollsodep pue uoIsolg XI “SUOT}VVIION [AAd'T *AIMNQSOYM? AL “(EG61) UlYsOD BIG 9UI00}SI9]q -urvodan pure YWJOMST[e HL (g) (Z) (1) *SuOTgIpuod o1yeuntyO “10S “UOLPRIUBUIIPIg ‘advospuvyT JO a3e4g aBVyS poysesang *Sa]Vog aUILy, dAIZR4UaT, *panuryu0jg— *Abojou0Ly,) “‘panuyuoj— se ATaV.L 84 WALKER AND HAWKINS. From a consideration of the nature of the deposit, subsequent soil develop- ment and elevation, these formations were correlated with reported high Pleistocene levels of the Pacific Ocean. On available evidence the change from the lateritic to the non-lateritic type of weathering was dated as mid-Pleistocene. The system was interpreted as being largely the product of alternating periods of landscape instability (erosion and deposition) and stability (soil formation). A tentative chronological table was drawn up. ACKNOWLEDGEMENTS. The authors wish to acknowledge the suggestions and criticisms made by a number of colleagues during a field excursion to the area under discussion. In particular, the authors are indebted to Mr. B. E. Butler, C.S.I.R.O. Division of Soils, Canberra ; Mr. A. N. Old (Senior Chemist), Dr. J. D. Colwell, Mr. J. A. Beattie and Mr. R. KR. Storrier, of the New South Wales Department of Agri- culture. Thanks are due to Mr. T. H. Johns, Chief Chemist, New South Wales Department of Agriculture, who read the manuscript, and to Miss E. Shannon and Mr. B. Fuller, who drew the diagrams. REFERENCES. Brothers, R. N., 1954. ‘‘ Relative Pleistocene Chronology of the South Kaipara District, New Zealand.”’ Trans. Roy. Soc., N.Z., 2, 82 (3), 677-694. Hallsworth, E. G., and Costin, A. B., 1953. ‘‘ Studies in Pedogenesis in New South Wales. IV. The Ironstone Soils.”” J. Soil Sci., 4 (1), 24. Huntington, E., 1914. ‘‘ The Climatic Factor ’’, pp. 23-36. Carnegie Institute, Washington. Jensen, H. I., 1911. ‘‘ The River Gravels Between Penrith and Windsor.’’ THts JOURNAL, 45, 249-257. Maze, W. H., 1945. ‘‘ Evidence of a Eustatic Strandline Movement of 100-150 Feet on the Coast of New South Wales.’ Proc. Linn. Soc. N.S.W., 70, 41-46. Prescott, J. A., and Pendleton, R. L., 1952. ‘‘ Laterite and Lateritic Soils.’’ Tech. Comm. No. 47, Comm. Bur. Soil Sci., Rothamsted Exp. Stn., Harpenden. Simonett, D. E., 1950. ‘‘ Sand Dunes near Castlereagh, New South Wales.” Aust. Geog., 5 (8), 3. Stearns, H. T., 1938. ‘‘ Ancient Shore Lines on the Island of Lanai, Hawaii.’’ Bull. Geol. Soc. Am., 49 (4), 615-628. —_-—_______— 1945. ‘‘ Eustatic Shore Lines in the Pacific.’ Bull. Geol. Soc. Am., 56, 1071-1078. Storrier, R., 1951. Honours Thesis (unpublished), Faculty of Agriculture, Sydney University. Tindale, B. 1947. ‘* Subdivision of Pleistocene Time in South Australia.” Rec. S. Aust. en 8 (4), 619-663. Whitehouse, F. W., 1940. ‘‘ Studies in the Late Geological History of Queensland.’ Univ, of Queensland Papers, Dept. Geol., 2 (N.S.), No. 1. Willan, T. L., 1925. Geological Map of the Sydney District, Dept. Mines, N.S.W. Woolnough, W. G., 1927. ‘‘ Presidential Address. Part I. The Chemical Criteria of Pene- planation. Part II. The Duricrust of Australia.” THis Journat, 61, 1-53. Zeuner, F. E., 1945. ‘‘ The Pleistocene, Its Climate, Chronology and Faunal Succession.” Ray Society, London. 1952. “‘ Dating the Past.” 3rd Ed. Methuen and Co. Ltd.: London. THE MINERALOGY OF THE COMMERCIAL DYKE CLAYS IN THE SYDNEY DISTRICT, N.S. W. By F. C. LoUGHNAN, and H. G. GOLDING. New South Wales University of Technology. With Plate I and two Text-figures. Manuscript received, April 4, 1957. Read May 1, 1957 ABSTRACT. Residual clays formed by the extensive leaching of Tertiary dykes in the Sydney district are predominantly kaolinitic, though illite is frequently present to the extent of 30%. The clays contain a relatively high percentage of titania, much of which occurs as distinctive leucoxene octahedra, believed to be pseudomorphous after ‘“‘titaniferous magnetite ’’. There is an association of illite with these octahedral forms of leucoxene. INTRODUCTION. The mineralogy of the Tertiary dyke clays occurring in the Sydney district is of interest for two reasons. Firstly, mineralogical data may enable the more effective commercial utilization of these materials; and secondly, such data may contribute to the elucidation of wider problems concerned with clay, soil and laterite genesis. The present study arose from independent observations by both authors. One of us (F.C.L.), during a broader investigation of N.S.W. commercial clays, previously had determined the clay minerals of the Sydney deposits, whilst the other first detected and checked by X-ray diffraction methods the presence of microscopically visible leucoxene of unusual characters in some of the same dyke clays. MINERALOGY AND ORIGIN OF THE DYKE CLAYS. The commercial dyke clays of the Sydney district are located principally in the French’s Forest area where they extend in a westerly trending belt from Narrabeen Lagoon to Asquith, a distance of approximately twelve miles. The dykes vary in width from a foot or two up to sixteen feet and have been worked to a depth of 40 feet or more. Some of the individual dykes comprising the system extend for several miles. Occasional short N-S trending dykes intersect the main belt. The country rock is generally sandstone of the Hawkesbury Formation but shale lenses of the same formation occasionally form the enclosing medium. The parent material of the clays was not observed at any point on the present survey ; however, the frequent occurrence throughout the Sydney area of fine grained dolerite dykes and other intrusions of Tertiary age leaves little doubt that the parent materials of the clays were of similar composition and that the environmental conditions in the French’s Forest area were favourable for the conversion to clay. The favourable conditions alluded to are the altitude of the region, the permeability of the Hawkesbury sandstone, and, 86 LOUGHNAN AND GOLDING. contingent on these, the considerable depth to the water table. Morrison (1904) noted that the dykes intruding the Hawkesbury Formation were almost invariably weathered to considerable depth whilst those intruding the Wianamatta Group were fresh. He attributed this to differential weathering. The clays are usually white but lack homogeneity and considerable areas are iron stained. Impregnation of the sandstone walls by iron oxides and hydroxides is common but metamorphic effects from the original dykes appear to be slight. Degrees C en ner aes a Ree es a a 100 300 500 700 goo 00 100 300 S00 700 Joo 1108 EE SS EE ee Eee ee eee eee Degrees C Text-fig. 1.—Differential Thermal curves of Dyke Clays from the Sydney Area. (I) St. Ives. (II) Belrose. (III) Narrabeen Lagoon, Examination of samples of the dyke-clays by X-ray, thermal and chemical techniques has shown that kaolinite is the predominant clay mineral, occasionally to the exclusion of all others, but illite is frequently present and at times comprises as much as 30% of the clay mineral content. The variability in mineral composition is evident by the differential thermal curves (Fig. 1). The sample from St. Ives is that of a well crystallized kaolinite and contrasts quite markedly with the illite-bearing kaolins from the Narrabeen Lagoon and Belrose areas. For the formation of kaolinite from a rock of doleritic composition the complete removal from the system of the alkalies, alkaline earths and iron, together with approximately 50% of the silica is necessary. A consideration MINERALOGY OF COMMERCIAL DYKE CLAYS IN SYDNEY DISTRIOT. 87 TaBLeE I. Chemical Analyses of Dyke Clays and Parent Material. I II Ill. IV SiO, 43-6 49-9 43-1 42-5 Al,O; 37-8 29-0 34-0 15-7 Fe,0O, 0-3 2-3 0-7 3°5 FeO — — — — Os 3°0 5-9 5:7 1-9 MgO — — — eZ, CaO.. — — — 9-5 K,O 2-7 2°3 0-7 1-8 Na,O — — a aoa H,O+ 9-6 9-5 12°3 2-2 H,O— 2-6 0-3 3°0 0-6 Total she 99-6 99-2 99-5 = Si0,/Al,0, ote Ts 1-72 1-27 2-70 Al,O,/TiO, ae 12-60 4-82 6-00 8-0 I. Dyke Clay—M.L. 28, Ph. Manly Cove, Co. Cumberland. Il. ey ” M.L. 40, 9 ” ” ” ” ITT. » Por. 341, ,, Gordon, EV Average of seven dyke rocks from the Sydney area after H. P. White and J. C. Mingaye (1904). of the chemical analysis (Table 1) of three dyke clays and the average for seven dolerites of the Sydney district shows this trend. Goldschmidt (1937) has shown 5 «Rb °Ba oK °Sr Ae _| Soluble cations \\ " he ola Vv W ° Na, Cu > 5 °Mn Hydrolzates I oZn,Fe ° Pb (oe “Mg = < = oS Soluble complex anions of 5 6 7 Z 3 “ IONIC CHARGE =2 Text-fig. 2.—Stability of the various ions as a function of the ionic potential (Z/r). After Goldschmidt, 1937. (see Fig. 2) that the stability of the various ions in a leaching environment is a function of the ionic potential (i.e. the ratio of charge to radius). Consequently, of the ions occurring in the original dolerite, titanium and 88 LOUGHNAN AND GOLDING. aluminium were the most stable and the alkalies and alkaline earths the least stable, silica occupied an intermediate position which depended on the pH of the leaching solutions. A spectrographic analysis (see Table 2) carried out on three dolerites and three dyke clays from the Sydney district supports Goldschmidt’s findings. However, potash behaves anomalously in two of the dyke-clays and it is significant that both of these clays contain illite. Apparently the ability of potassium to enter into twelve co-ordination in the formation of the hydrous mica not only prevented its loss from the system but, further, TABLE 2. Spectrographic Analysis. Element. il IBGE Td IDV. Vv. VI. Li Ay — —- T M — Na s S s av Ww WwW K M M M — M M Mg V.S. V.S. VS. WwW Ww Ww Ca Ss Ss S W WwW Ww Cu M M M WwW WwW Ww Fe Ss Ss Ss M M M Mn Ss Ss Ss — a -= Pb W W W M W WwW Sn — — -—— Tt M — Ti M M M Ss Ss S Zn Ab f¥ —_ — —_ — V.S., very strong; 8S, strong; M, medium; W, weak; T, trace. I. Dolerite Dyke, Bondi. Il. = Pr Narrabeen. Il. Be Sill, de Burgh’s Bridge. IV. Dyke clay, St. Ives. V. 33 5 Belrose. VI. zi ss Oxford Falls. enabled the stabilization of some of the silica by the formation of the illite— 2:1 (silica to alumina)—lattice as opposed to the 1: 1—lattice of kaolinite, which the leaching conditions favoured. Jackson et alii found illite common in the highly leached kaoline of Hawaii, some of which contained titania in excess of 30%. MINERALOGICAL FORM OF THE TITANIA. Previous references to the mineralogical form of the titania present in various clays are somewhat speculative; thus the titania has been referred wholly or partly to the following mineral groups : 1. Doubtful titanium compounds not visible macroscopically (Goldschmidt, 1954; McLaughlin, 1954). 2. Anatase detected by X-ray analysis but not represented by micro- scopically visible particles (Brindley and Robinson, 1947 ; Nagelschmidt et alti, 1949; McLaughlin, 1955). 3. Microscopically detectable discrete crystals of various titanium minerals (Simpson, 1928; Carroll, 1934; Brindley and Robinson, 1947; Frederickson, 1948). MINERALOGY OF COMMERCIAL DYKE CLAYS IN SYDNEY DISTRICT. 89 4. Microscopically visible leucoxene as rounded or angular grains or earthy or crust-like material associated with minerals of group 3 (Edwards, 1942; Frederickson, 1948; Goldman, 1955). Leucoxene varies in crystallinity and purity but usually it gives the X-ray powder pattern of rutile, anatase, brookite or sphene (Tyler and Marsden, 1938 ; Frederickson, 1948 ; Allen, 1949 and 1956; Golding, 1955.) In the Sydney dyke-clays examined, much of the titanium occurs as microscopically visible leucoxene grains many of which exhibit well faceted but skeletal octahedral forms. The grains are dull and cream coloured in reflected light, and opaque to transmitted light but some show a pale cloudy aggregate polarization indicative of their polycrystalline (leucoxenic) constitution. The grains have similarities to the mat-surfaced grains present in some dune-sands (Golding, 1955) but differ from them in being more friable and in displaying faceted forms. The powdered leucoxene gives the X-ray pattern for anatase. Leucoxene-rich concentrates were prepared by sieving suspensions of clay to recover the plus 50 micron material, which was then fractioned in bromoform. The light bromoform fractions of most samples consisted of clay flakes and pellets usually peppered with small faceted leucoxenes or with blebs or plates of leucoxene. A few grains of wind-blown quartz, derived from the surrounding sandstone, also occur. The heavy bromoform fractions of most samples consisted largely of leucoxene octahedra 0-1 to 0-2 mm. wide showing hopper or hollow faces (Figs. 1-5 and Figs. 7 and 8) or parallel growths (Fig. 6). - +0 +1490? +0 -01775 +0 -006%8 +0 00st. BOUNDARY STRESSES IN AN INFINITE HUB OF SPECIAL SHAPE. 113 (o) Towards solving (6) we note that ae is the boundary value of the rational @ (oO function w(Z) _y9 0-825 +0-1497 +0 -1077° +0 00629 +0 -003¢? ) ~ > (—0-82572-++0 -2987° +0 -08578 +0 - 04873 +0 -033 y = —{0-00479 +0 -0087° +0 -02473 +. 0-190} +terms in a 7 . . ete. which is holomorphic outside 7 except at €= 00, where it has a pole of order 9. Now ¢(¢) is holomorphic inside y, so that 9’(c) is the boundary value of my (2); holomorphic outside y. Hence (6) a)'(o) o’(o) is the boundary value of ake ° (2) holomorphic outside y except at C= oo, where it has a pole “(yt of order 9. Aecuutiuy 9(G)=a,5+a.0?+. : a,c? +. ee in | Gilrew, then na, a (gat er - sateen. for | C/I. Therefore, in the present case, for | ¢|>1 5 ame al —— 10+0(5) oe (9) where K,—0-072d, +0 -048a, +0 -0364, K,=0-0484a, +0 -0404, +0 -0324, K,=0 -0244a, +0 -0324, +0 -0284, -024a, +0 -024a, SOUGGa Ur OL0 Ges We ictetene crarelaae Ga) asa +0 - 0067 +0 - 00374} Str (14) Comparing coefficients on both sides and substituting for K,, K., .. ., Ko, we have xd, +0 +07243 +0 +0484, +0-0364,=0 xa, +0-0484, +0 -0404, +0 -0324,—2yiae (0-149) xa, +0 -024d4, +0 +0324, +0 -028a4,—0 xa, +0-0244,-+0-0244, =) xa, +0-0164,-+0-0204; == Duras (OnONG) ta gti: crete (15) xa, +0-008a, +0 -016a, = xa,+0-0124, ==0 xa, +0 -0084, =2uiae (0-006) xa, +0-0044, = XA9 = X44 =2utae (0-003). Putting a,=a,+i8,,...,a,=a,+i6, and equating real and imaginary parts we find that all «’s are zero and all #’s are zero except (., 8;, Bg, and 6,,;. Thus the only equations which concern us here are (x —0-048)8, —0-0408, —0-0328,.=2uae (0-149) (x —0-020)8, —0-0168, —2Quac (0-017) .....----- (16) xB,—0-0088, —2uae (0-006) *Pi —2uae (0-003). Solving (16), neglecting terms of order 10-5, we have syne | 02 149%—0-002 ee aks x2—0-068x 0-017x+0-001 Ps = diite ae pRee 0-001 oy mel 07006% +0 001 By =2uae| 2 0.068% ene ° -003 and p(T) =#[ Bol? +BsC>+BeCo+Pio7)] «- eee (18) BOUNDARY STRESSES IN AN INFINITE HUB OF SPECIAL SHAPE. 115 and since a,—7i8., a;=i6;, etc., we have from (10) K,= —0-04878, —0-04078, —0-0326, K,=—0-01628, —0-02078, K,=—0-00878,, all other K’s being zero, K, not being required. Hence (9) can be rewritten as follows : 1b ey (Ret eal ele #(7) BN ate. Kt —Kt +0 > | eee (9’) wo’ ls (:) Taking the conjugate of this equation we see that in | ¢| <1, ONG ee. | Bia) Bie Ke HOwoa ee eS +a Holomorphic Function .. (19) (oc) a@’(o) Considering the second integral in (7), the function © 2] (:) o'(0)* order 8. Thus the Cauchy Integral 1 | (5) 9'(s) Qnt y w'(o) o—F o’(c) is the boundary value of (¢), holomorphic inside y except €=0, where it has a pole of do=the holomorphic function in (19). Now, on the boundary of the hub, using (12), j= ~iae} 0 8256-4" = a0 aa a? a ee ot crepe (21) so that = : 0 = +2uiae (0 -825Z) Thus equation (7) yields me | o(;) ie sie, 21 (6) =2piae (08250) — re e'(0)— a a 7 eee (22) RELATION BETWEEN MOMENT OF APPLIED COUPLE AND e. The moment M of forces acting on the boundary of the hub about the centre will be equal and opposite to the moment of forces acting on the shaft in the vicinity of the hub about the centre. This moment is given by the real part 116 ALEX REICHEL. of the change in Aa (2 —ap, (2) —22¢1(2) as 2 moves around the contour L clockwise (cf. Muskhelishvili’s ead he 33.3, in which there is a misprint), where = [uae +constant. Since (7), p’(¢) and Y(C) are holomorphic inside y, ¢1(z) and (2) are holomorphic outside LZ, so that we need only calculate the real he of the increase in as € moves around y anti-clockwise. Thus we need the multivalued term in Re fH t)o" Cat, ie. in Re | \2uiae (0-825)t0'@)—0(} 9°) (stett elo mle. .. (23) This multivalued term is Re[{—2uica? (0-825)?—ia (0-2988,-+0-0858, +0-0488,+0-0338,,) —@ (0-298K,+-0-085K, 4-0 -048.K)) Imi Gh wea eet eee eee (24) From (10), A,—0-048i8,+0-040i8,-+0-032i0, K,—0-016i8, +-0-020i8 , K,=0-008i8,. Substituting in (24) and simplifying, we find =2r{2Quea? (0-825)? +B, (0-313) +48, (0-099) +48, (0-058) +a8,, (0:033)} POET AR (25) JALCULATION OF STRESS COMPONENTS. The components of stress in orthogonal curvilinear co-ordinates (p), (0) are given by the formule (50.9), (50.10) in Muskhelishvili. A rearrangement gives fo +Go—sRe! St “maakt eee (26) and ‘ =~ r~ — 972 a 60 —pp +2igb= oe [ee «(C) ere fr¥eo], NO Vay: (27) When p=1, 20, 60, 0 give the normal, tangential and shear stresses on the boundary of the hub corresponding to values of 8 in the C-plane. Equation (26) presents no difficulty. We find, putting p=1, 4a (B sin 30-+C sin 60+D sin 90 +2 sin 120) a* (0-780 —0-430 cos 30 —0-106 cos 60 —0-060 cos 99 —0-054 cos 120) vate Aho cae (28) pp +60 = BOUNDARY STRESSES IN AN INFINITE HUB OF SPECIAL SHAPE. a taly; where B=1-8208, —1-2508, —0-4168, —0-5288,, C=0-0968,-+4-2908, —2-3848,—0-935B,, D=0-0668, +6 -6008,—3-2788,, E=9-0758,,. Towards evaluating (27), we note that @'(S)) — @(T)w'(Z) p(T) —w(Z) 9’ (7) w’"(Z) . Oa een (Ce clea i) and from the expression (22) for }(¢) we find Pacey an, Y(C)—2uiae (0-825) +B gs — o'@a(e)e"® o(z)e@o"® 17) eee eee (30) Or * wr Substituting from (29) and (30) in (27) we find 66 —pp +2i90— Since on the boundary of +, ofa) 5) we have, putting p=1 and o=e’*®, ee es a De2i0 00 —pp +2700 = ——____ |2uiae (0 -825)a'(c) «’(6)a@'(a) (2K, 5K, 8K) , a = aa eae i d Say Ea , me c) qo lO? (2)] Wore (31) Substituting in (31) for w'(c), @'(6), Ko, K,, Kg, etc., and separating the real and imaginary parts of each term in turn we find firstly — p0= rare’ +B’ cos 30+C’ cos 60+-D’ cos 969+-E’ cos 120] .. (32) | w’( where A’=0-6358,+0-4588,+0-4038,+0-3638,, —2uea (0-681) B' = —1-5168,+1-7068,+0-8968,+0-5288,,+2yea (0-246) C' =0-0578, —4 -0268,, +2 -3878,+0-9358,,+2uea (0-070) D’=0-0168,+0-0038,—6 -5988,+3-2788,, +2uea (0-040) E’ = —9-0758,, +2uea (0-027). 118 ALEX REICHEL. Combining the expression for 66—o¢ from (31) with 00-+0 from (28), we find ep =. [B” sin 30-0” sin 60-+.D” sin 90-+-2”” sin 126]'0.2..%33) | ® (co) |? where B’’=1-8848, —1-2028, —0-3588, —0-5288,, +2uea (0-246) C’’ =0-1518,+4-3808; —2-3818, —0-9358,, +2uea (0-070) D’ =0-1228,+0-0038;+6 -6028, —3-2788,,++2uea (0-040) E” =9-0758,, +2uea (0-027). Also 0= Sar [B” sin 30+0” sin 60+D” sin 99+” sin120] .... (34 where B”= 5-3968,— 3-7988,;— 1-3068,—1-5848,, —2uea (0-246) C”—= 0-2338,+12-7808;— 7-1558,—2-8058,, —2uea (0-070) D"= 0:1428,— 0-0038;+19-7988, —9 -8348,, —2uea (0-040) Ei” =27 -2258,, —2uea (0-027). Text-fig. 4. RESULTS FOR SPECIAL MATERIAL. GRAPHS. Choosing steel as the special material, with Poisson’s Ratio 0.30, we have x=1-80. Then, from (17) 6B, =2uae (0-085) Bs —2Zpae (0-010). 5... one ee a8 (35) B, =2uae (0-004) ) The value of < for a given couple with moment M is given from (25) ) M ~~ Arua? (0-709) 0.2 (0 je) ©) © © efete ale, ale « «0.6 BOUNDARY STRESSES IN AN INFINITE HUB OF SPECIAL SHAPE. 119 From (32), (33), (34) A ve (1:240—0 +277 cos 30 —0 -087 cos 69 —0-043 cos 96 —0-025 cos 126) aa (0-780 —0-430 cos 30 —0-106 cos 68 —0-060 cos 99 —0-054 cos 120) Sag Peeneney ara ara ska (37) > pe (0-784 sin 30 +0-246 sin 60 +0-141 sin 90 +-0-083 sin 120) Pe (0-780 —0-430 cos 30 —0-106 cos 69 —0-060 cos 98 —0-054 cos 128) and 6p— HE (0-335 sin 30+0-102 sin 60+0-063 sin 96+-0-033 sin 126) ~ (0:780 —0-430 cos 30—0-106 cos 69 —0-060 cos 99 —0-054 cos 120) Seretinte wees Sok (39) The graphs of 00, 60 and 90 against § are shown in Text-figure 4. By choosing the positive directions of pe, 00, 0 as shown we can show the stresses along the edge of the hole for values of angle ® from 0 to 120°. The stresses are repeated on each of the other two edges. The values of ® corresponding to the values of § from the graphs can be obtained from Text-figure 3. REFERENCES. Muskhelishvili, N. I., 1953. ‘‘ Some Basic Problems of the Mathematical Theory of Elasticity.’’ INGVin Ee Noordhoff, Holland. Nehari, Zeev, 1952. ‘‘ Conformal Mapping.” McGraw, Hill. BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND IN THE SNOWY MOUNTAINS OF NEW SOUTH WALES. By GERMAINE A. JOPLIN, Department of Geophysics, Australian National University. With Seven Text-Figures. Manuscript received, June 26, 1957. Read, August 7, 1957. ABSTRACT. A number of basic and ultrabasic rocks occurring within the area drained by the Upper Tumut and Happy Jacks Rivers have been described. These include pyroxenites, hornblendites, gabbros, diorites, monzonites, lamprophyres and a number of other types occurring as minor dykes and veins. It is believed that they are all related, and that they have been derived partly by differentiation and partly by assimilation during the Bowning Orogeny just prior to the emplacement of the granite. It is suggested that the basic parent is an earlier intrusion of Ordovician age, possibly related to the Porphyritic Central Magma type, and that the acid parent is the (?) Silurian granite magma, or partial magma. CONTENTS Page 1. Introduction . . ais a3 ae te ae on x ». 120 2. Field Occurrence .. ies AG Je ae He Sp a. | L2H 3. Petrography . ho .. 123 Pyroxenite, Hornblende- yroxenite and Hornblendite 0 SR Hornblende-gabbros’.. C Ab atc ae ae) Ze: Diorites .. in awe a oe ZG Orthoclase- diorites and ‘Monzonites a are fe ac a Za Hornblende-lamprophyres BO ate $6 ac ou re e28) Mica-lamprophyres Be Bip BI ae ats = na | Lill Mica-porphyrites ale a dc 56 Sib me SZ Hornblende-quartz- -porphyrites oie bso 5.6 xe do ley Dolerites .. : ava a 5 co LES 4. Nomenclature of the Orihodlase: Bearing Hecke. site as ese 5. Mutual Relations of the Different Rock Types .. oe ae s+ Se 6. Origin of the Basic Rocks .. 3 au ia at se se) LSD Differentiation versus Assimilation as 5 ats ha Sy | USS Nature of the Basic Parent .. Se Ao bcs me ao theks The Hybridization Process... fe He 66 re go UGH!) 7. References .. a3 as ae 3.6 os au ite :. 140 INTRODUCTION. Andrews (1901) briefly referred to the occurrence of norite and of syenitic diorites at Kiandra, and later Browne and Greig (1923) described the so-called norite in detail and designated it an olivine-bearing quartz-monzonite. Recent work by the Geological Survey of New South Wales (Hall and Lloyd, 1954) and by the Engineering Geology Section of the Snowy Mountains Hydro-Electric BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND. 121 Authority has revealed many occurrences of closely related rocks to the south of Kiandra, including ultrabasic, basic and intermediate types. Many of these have been mapped at the surface and others have been encountered in the tunnels and in the exploratory drill holes. According to Vallance (1953) similar types occur 34 miles to the north- north-west on the same line of strike. To the east, near Cooma, and in the region north of Cooma, several small basic and ultrabasic masses are recorded (Browne, 1914; Joplin, 1939, 1942). These bear no close resemblance to the Snowy Mountains rocks and appear to be of Ordovician age. Basic granulites of probable Ordovician age are also recorded near Cooma and later work (Browne, 1944 and Joplin, 1943) shows that several of these masses occur to the north of Murrumbucca, and the former presence of others is suggested by the occurrence of numerous basic xenoliths in the (?) Silurian granite. N. J. Snelling, of this department, is at present engaged on a very complete study of this granite and has kindly made available several analyses of the basic xenoliths, some of which he suggests are of sedimentary origin. Recent work in the Mt. Isa-Cloncurry district of Queensland has raised the problem of distinguishing between metamorphosed basic igneous and calesilicate rocks (Walker and Joplin in MS.) and it is indeed possible that some of the Cooma granulites are in fact highly altered banded calcareous rocks. In the present paper an attempt is made to examine the relation between the different basic types within the Tumut Pond and Happy Jacks area and then to compare them with the other basic types recorded to the north and to the east. Their origin and their relation to the granite are also discussed in relation to the diastrophism with which they are believed to be associated. The writer would like to acknowledge her indebtedness to the Snowy Mountains Hydro-Electric Authority, and in particular to their Chief Geologist, Mr. D. G. Moye for the loan of slides, specimens and maps ; to Dr. W. R. Browne for kindly criticism and for the loan of specimens from the Kosciusko region collected by himself and by the late Sir Edgeworth David; and to Mr. C. McElroy, of the Geological Survey of New South Wales, for the loan of specimens and for discussion on the field occurrence of the rocks in the southern part of the area. She also wishes to thank Mr. N. J. Snelling for his generosity in permitting her to use several of his unpublished analyses for the plots in Fig. 7. 2. FIELD OCCURRENCE. Reference to Fig. 1 will show that numerous small masses of basic rock occur within the region drained by the Upper Tumut and Happy Jacks Rivers. Masses A and B were mapped by Andrews (1901) and referred to as norite and syenitic diorite respectively. Most of the other masses were mapped by Hall and Lloyd (1954) and are referred to under the collective term Jagungal-Nine Mile Complex. The larger masses are narrow elongated bodies trending approximately N. 60° E., roughly parallel to the margins of the granite. In places the basic rock is adjacent to the granite, and shows contact alteration as a result. Both within and outside the area delineated in Fig. 1, small basic dykes invade the country rocks. Some of these are possibly of Tertiary age, but many are older and closely allied to the basic types described in this paper. Dykes of lamprophyre cutting both country rocks and granite have been examined by the late Sir Edgeworth David and by Dr. W. R. Browne in the Kosciusko area, and these are briefly referred to in the petrography. Just north of Tumut Pond, an elongated mass of serpentine trends N. 5° W., but as the strike is different and it is magmatically dissimilar to the rocks here considered, it is not discussed herein. Although specimens from bores and tunnels and from several different outcrops have been lent by the Snowy Mountains Hydro-Electric Authority, the 122 GERMAINE A. JOPLIN. writer herself has examined only three outcrops in the field. Her impression is that, with but few exceptions, the different types grade one into the other and rarely show clear boundaries. Thus in the elongated mass parallel te the Tumut River, and about 2 miles south of Junction Shaft (Locality K), large patches of pyroxenite contain patches and veins of coarse hornblendite and both grade out into gabbro and finer grained dioritic types, all being intersected by veins of = <<") <=KIANDRA 1 FA NEN gt CABRAMURR A—! No Granite? , * “So F NOENS aa |. a ives, Intrus Je pu ww ut 7 rs Fan ~ 4 LLG, NENG ys SS SS oy SNE DN Miles Text-fig. 1.—Map of the Tumut Pond-Happy Jacks area showing localities of basic rocks. epidote, quartz, calcite and fine hornblende rock. Only the most detailed mapping could delimit these types, and even then junctions would probably prove indefinite and unsatisfactory. In the “ Diorite ” quarry within the small heart-shaped mass 2 miles south- south-east of Junction Shaft (Locality G), two types predominate, a fine grained hornblendic rock cut by a lighter type with large uralitized pyroxene phenocrysts. Both are orthoclase-bearing and show affinities to the monzonite, and in places BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND. 123 both assume a pinkish colour which appears to be due to the invasion of later solutions. The core of a bore (5193) put down though this mass shows that it consists mainly of these types and that alteration is very common. Dolerites, mica lamprophyres and porphyrites are also found in the core and probably represent small dykes or veins. As both a quarry and a bore core are available at this locality, much of the described and analysed material comes from this mass. Most of the other masses consist predominantly of orthoclase-bearing diorites or monzonites, but the other types are commonly associated in small amount, and again the field relations are not clear, though it is possible that some order of intrusion might be established if other quarry exposures were available. Small irregular bodies of pyroxenite and of monzonite and numerous dykes of dolerite, lamprophyre and porphyrite have been encountered in the Hucumbene- Tumut Tunnel, and a number of such dykes are exposed in the road cuttings near Junction Shaft. These, together with small veins of similar type, as well as of epidote, calcite and quartz, appear to be the only well-defined discrete injections. Veining by acid material even close to the granite is rare, though the pink coloration due to alteration may be mistaken for it in places. Except for the absence of this feature, the field relations of the basic and ultrabasic rocks show a remarkable resemblance to those of the Ach’uaine hybrids of Sutherland, Scotland (Read, 1931). Though genetically unrelated, the field occurrence is not unlike that of a group of basic rocks at Cooma (Joplin, 1939). 3. PETROGRAPHY. Pyroxenites, Hornblende-pyroxenites and Hornblendites. Pyroxenites, hornblende-pyroxenites and hornblendites show all gradations from one into the other and are here described together. They form small areas within some of the basic intrusions, and are commonly surrounded by and grade out into less basic types. A large mass crops out near the road about 2 miles south-south-east of Junction Shaft and a smaller irregular intrusion is found between stations 506+-70 and 508-+50 in the Eucumbene-Tumut Tunnel. Dr. W. R. Browne (pers. comm.) has also found pyroxenite included in granite and impregnated with tourmaline near Seaman’s Hut in the Kosciusko area. It is also of interest to note that Vallance (1953) found an ultra-basic inclusion, with a chemical composition approximating to that of the pyroxenite, in the Wantabadgery granite about 30 miles north- north-west of Kiandra. In hand specimens these rocks are dark and coarse-grained with hornblende crystals in some specimens measuring up to 15 mm. Under the microscope the pyroxenites have a fairly even grain size which may range in different specimens from 1 to 6 mm., and the fabric is from allotriomorphie granular to hypidiomorphic granular (Fig. 2A). The bulk of the pyroxene is pale green, optically positive witn Z /\ c=54° and a slight polysynthetic twinning sometimes apparent. It thus appears to be diopsidic. A negative, slightly pleochroic pink pyroxene is also present in small amount. Some sections show an oblique extinction and it was suggested by Browne and Greig (1923), who found the same variety in the Kiandra monzonite, that it is a monoclinic clino-hypersthene. Both pyroxenes contain inclusions of magnetite which may grow outwards and link with schiller inclusions of the same material. Flecking with small patches of green hornblende is common and the pyroxenes are often wrapped by irregular grains (1mm.) of brown hornblende with Z—dark olive green, Y=golden yellow and X=pale yellow. Green hornblende may also form independent grains with Z=dark green, Y=olive green and X=greenish yellow, Z 2 5 8 = @ & H a =) p> ° = | S jon [o) S S) Bs ce a x ea) fo) = - AE 1 17-9 40-1 5:9 2123 7:2 6-3 0:6 0-7 — 35-4 2. 14-7 44-2 5:5 22°8 5:3 6-2 Tr 1-3 — 34-3 3. 12-4 39-3 6-7 26-7 8-0 5-1 —- 1-9 — 39-8 4. 11-4 42-4 729 22-9 7:6 5-6 0-3 1-9 — 36-1 5. 11-2 47-6 8-6 13-6 13-8 3-6 —- 1-6 — 31-0 6. 10-7 47-7 19-8 2-6 11-9 5-1 -- 1-6 — 19-6 Ts 9-2 52-7 12-5 — 9-0 15-1 — 0-6 — 24-1 8. 8-6 36°8 5:2 —_ 35-8* 5-27t) — -- 8-6 41-0 9. 7:6 46-1 9-8 8-8 11:9 13-2 — 2-7 — 33-9 10. 7-2 49-0 21-6 8-9 7-6 5-3 — 0-4 — 21-8 11. 7-1 52-4 7°5 9-0 9-5 11-5 —— 2°6 —_ 30-0 12. 6-3 49-5 19-4 6-1 8-5 9-2 — 0-9 — 23-8 13. 4-7 48-7 7:6 — 28-4* 10-07 — 0-7 — 38-4 14. 4-4 44-9 13-9 5-2 17-4 10-8 -- 2°5 0-7 34-1 15. 4-3 30-5 8-9 10-3 42-7* 2-0ft|; — 1-1 — 55-0 16. 4-3 43-8 15-8 1-2 20-6 5:8 —- 1-8 Graz, 27°6 Wie 3°7 56-3 5-6 5-0 18:5 8-4 2-5 — 31-9 18. 3-6 46-8 13-0 3:6 20-4 9-8 — 2-8 — 33°8 19. 1-4 54-4 5-6 29-2 1-9 5-1 —- 2-3 = 36-2 20. 1-4 30°7 3°9 4-1 54-+3* 5-1ft} — 0-5 — 63-5 Note: Uralite has been counted as pyroxene when it was obviously so derived. Doubtful cases have been counted as hornblende. * Partly chloritized. + Wholly chloritized. { Epidotized. 1. Kiandra (Locality A), Anal. W. R. Browne, Journ. Roy. Soc. N.S.W., 56, 1922, 261. (Anal. VII, Table ITT). 2-3. Kiandra, Anal. G. A. Joplin. 4. Kiandra (Locality A), Anal. G. A. Joplin. 5. Locality G. 2} miles S.E. of Junction Shaft. Anal. G. A. Joplin. 6. Locality J. One mile 8.8.E. of Junction Shaft. Anal. G. A. Joplin. 7. Locality I. One mile East of Junction Shaft. Anal. G. A. Joplin. 8. Locality G. Bore 5193 at 428 ft. (Anal. IV, Table III). Anal. G. A. Joplin. 9-10. Locality G. Bore 5193 at 170 ft. (Anal. V, Table III). Anal. G. A. Joplin. 11. Locality J. Anal. G. A. Joplin. 12. Locality G. ‘* Diorite”’ Quarry. Anal. G. A. Joplin. 13. Locality G. Bore 5193 at 248 ft. (Anal. III, Table III). Anal. G. A. Joplin. 14. Locality G. Bore 5193 at 470 ft. Anal. G. A. Joplin. 15. Locality G. ” Diorite’ Quarry (Anal. I, Table III). Anal. G. A. Joplin. 16. Locality G. ‘* Diorite”’ Quarry. Anal. G. A. Joplin. 17. Locality G. Bore 5191 at 290 fr. Anal. G. A. Joplin. 18. Locality G. Bore 5193 at 90 ft. Anal. G. A. Joplin. 19. Locality G. ‘* Diorite”’ Quarry. (Anal. II, Table III). Anal. F. A. Joplin. 20. Locality I. One mile east of Junction Shaft. Anal. G. A. Joplin. texture the felspar forms small tabular crystals that measure from 0-3 to 0:75 x 0-2mm. Much of the felspar is saussuritized and alteration to calcite is common. Quartz is present in most of these rocks, and many of them show a fine quartz veining. In the finer grainer types quartz is present in small fine grained BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND. 131 aggregates (see Fig. 54), and in the coarser groundmasses it occurs interstitially amongst plagioclase crystals. Except for the habit of the amphibole, the coarser groundmasses resemble fine grained quartz-diorites. According to Iddings (1913, p. 200), such rocks are more closely related to spessartites than to camptonites on account of the larger amount of amphibole in their groundmass and of the presence of quartz. Mica-Lamprophyre. This rock occurs in the borehole at Locality G. and is also met with as dykes at stations 452+-75 and 532-+-00 in the Eucumbene-Tumut Tunnel. As yet it has not been recognized as a surface outcrop in the Tumut Pond area, but the Zi vy it ee Z yi oa x LAN; ys We ZW NY Text-fig. 5. (A) Hornblende-lamprophyre from Locality I, showing large idiomorphic phenocrysts of greenish-brown hornblende in a plexus of small idiomorphic laths of hornblende and plagioclase. Magnetite is accessory and in places small aggregates of quartz grains occur, and elsewhere this rock is veined with quartz. x 10. (B) Mica-lamprophyre from Locality G, showing large phenocrysts pseudomorphed by carbonates, quartz, chlorite and magnetite, smaller phenocrysts of biotite in a groundmass of plagioclase, elongated plates of biotite, chlorite and magnetite. x 10. writer has examined a similar rock collected from a dyke by the late Sir Edgeworth David at Thompson’s Flat, near Kosciusko, and two closely related types collected by Dr. W. R. Browne east of Boggy Plains from dykes intruding the granite. : The specimen from the borehole occurs at the 329-foot level and possibly represents a vein intrusive into monzonites. It is porphyritic with idiomorphic phenocrysts up to 4-5 mm. completely pseudomorphed by aggregates of carbonate, quartz, chlorite and magnetite (Fig. 56) suggesting original pyroxene. In the Thompson’s Flat rock a little fresh pyroxene remains as cores, though most of it is altered to uralite and chlorite with a trace of carbonate. Both of the Boggy Plains specimens contain much fresh pyroxene, though some phenocrysts are entirely altered to chlorite. One of these rocks contains a pyroxene pheno- cryst with a completely serpentinized inclusion suggesting the former presence of 132 GERMAINE A. JOPLIN. olivine. Phenocrysts in the rocks from the Eucumbene-Tumut Tunnel are also altered to chlorite, but a little carbonate is also present, the dyke at station 523 +00 being the more altered and less characteristic of the group. One of the Boggy Plains rocks contains a few altered phenocrysts of plagio- clase. In the borehole specimen biotite also occurs as small phenocrysts in extremely elongated thin plates which show every gradation into the smaller flakes of the groundmass. In this rock the groundmass has an average grain size of 0:75 mm. and consists of plagioclase, biotite, chlorite, carbonates and quartz with accessory magnetite. The Boggy Plains rocks differ from one another in regard to the groundmass. One contains almost completely chloritized flakes of biotite and is slightly more felspathic with some pyrites ; the other has an extremely fine grained groundmass consisting of plagioclase, augite and magnetite. These rocks bear a close resemblance to kersantites—rocks that Iddings (1913, p. 199) considered to be related to the monzonites—and it is of interest to note that Harper (1919) recorded kersantite dykes in the Adelong granite some thirty miles to the north-north-west, where Vallance (1953) has described other types comparable to the basic rocks in the Snowy Mts. area. The analysis of the Adelong kersantite is plotted on the AFC diagram (Fig. 7) at point 10 and thus falls within the field of the Snowy Mts. rocks. Mica-Porphyrites. A vein of this material occurs at 409 feet in the borehole 5193 at Locality G. It is a porphyritic rock with a fluidal groundmass. Comparatively fresh, zoned felspar occurs as phenocrysts about 2 mm. in diameter and granular aggregates of quartz, carbonates and chlorite suggest the former presence of augite pheno- crysts. The groundmass consists of plagioclase, quartz and biotite, the last delineating a well marked fluidal fabric. Except for the presence of plagioclase phenocrysts, this rock is not unlike the mica-lamprophyre occurring 80 feet above it. Hornblende-quartz-porphyrites. At stations 654-++00 and 649+50 in the Eucumbene-Tumut Tunnel an irregular-shaped body occurs which appears to be contact-altered and in places sheared. It is a porphyritic rock with phenocrysts of plagioclase, quartz and an altered ferromagnesian mineral, presumably hornblende, in a very fine groundmass. In the contact-altered rock the ferromagnesian phenocrysts consist of aggregates of criss-cross flakes of reddish brown biotite, obviously pseudo- morphing an idiomorphic mineral suggesting hornblende. In the sheared rock these phenocrysts are not well defined and consist of elongated patches of chlorite and iron ores. Quartz forms idiomorphic crystals (up to 3 mm.) slightly corroded and in the sheared rock it is granulated and strained, although some evidence of strain is also apparent in the thermally altered type. Plagioclase forms tabular crystals up to 2-5 mm. and is slightly sericitized in the contact rock, but in the sheared specimen it is only just recognisable as an aggregate of sericite, quartz, chlorite and iron ore which merges into a ground- mass consisting of the same minerals. The groundmass of the contact-altered rock forms an exceedingly fine crystalline mosaic. BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND. 133 Before alteration these rocks possibly showed some resemblance to the hornblende-lamprophyres, though the characteristic elongated amphibole crystals do not appear to have been present. Dolerites. Doleritic rocks occur in the bore 5193 at Locality G., in the bore 5057 about 1 mile upstream from the Tumut Pond dam site, and also as dykes in the Eucumbene-Tumut Tunnel. All are much altered and their identification is difficult and unsatisfactory. Furthermore, there are many individual differences between the rocks that are here grouped together. Unfortunately the present writer has not been able to examine specimens from Jagungal, but this rock has been described by Whitworth (1954) as an amphibolized dolerite with ophitic fabric and the mass is reported to be hornfelsed at the southern end where it is adjacent to the granite. In bore 5193 these rocks occur at 140 feet and at 177 feet. The upper one consists of laths and small tabular crystals (about 0-2 mm.) of plagioclase much altered to carbonates. These appear to have been wrapped by a ferromagnesian mineral now entirely altered to chlorite with small inclusions of magnetite. Quartz is interstitial. Small (about 2-5 mm. in diameter) ellipsoidal bodies infilled with plagioclase, quartz, carbonates and radiating chlorite were possibly original amygdules or vughs. Some of these have small acicular crystals of magnetite arranged around the outer margin. At 177 feet the rock is slightly coarser and contains a few much altered elongated crystals of mica suggesting a link with the mica-lamprophyre. This rock also contains epidote and pyrite. Several very similar rocks occur as dykes in the Eucumbene-Tumut Tunnel. They contain a great deal of calcite and are much altered, but individual des- criptions seem unnecessary. At 84 feet in bore 5057 a slightly sheared and coarser rock occurs. It contains rare phenocrysts of altered plagioclase in a subophitic groundmass consisting of heavily kaolinized plagioclase wrapped by subidiomorphic crystals of hornblende. Large grains of strained quartz are interstitial and the rock is veined by quartz and epidote. 4. NOMENCLATURE OF THE ORTHOCLASE-BEARING ROCKS. As noted above, the Kiandra rock was originally called a norite (Andrews, 1901) and later re-named an olivine-bearing quartz monzonite (Browne and Greig, 1923). This rock contains 17-9% of orthoclase and 40:1°% of plagioclase, and although it has a very distinct monzonitic fabric, it would not be regarded as a monzonite by Nockolds (1954), who considers that the ratio of the amount of potash felspar to total felspar should range within the limits of 40 and 60%, or by Iddings (1913) who lays down that the ratio of plagioclase to orthoclase should be from 5:3 to 3:5. Tyrrell (1928) considers that the amounts of plagioclase and of orthoclase should be about equal in the monzonites, and he points out that these rocks, as compared with the syenites, show an increase in ferromagnesian minerals and a more calcic plagioclase. Harker (1919), following Brogger, defines the monzonites as a group with orthoclase and plagioclase in approximately equal proportions. Reference to Table IV indicates that the volume percentage of orthoclase in a number of the Snowy rocks shows a wide range. These modal analyses are plotted on a triangular diagram in Fig. 6 to show the relative amounts of plagio- clase, orthoclase and ferromagnesian minerals. The diagram shows that none of the Snowy Mts. rocks falls within the area prescribed as that of the monzonites by 134 GERMAINE A. JOPLIN. Nockolds. Modal analyses have also been made of four specimens from the geological collections of the University of Sydney, namely, three monzonites from Mount Dromedary, N.S.W. (Brown, 1930) and one from the Tyrol. It will be noted that the Tyrol rock and one of the Dromedary rocks closely approach Nockolds’ boundary, that another Dromedary specimen falls among the Snowy Mts. rocks and that the third has an excess of orthoclase and approaches the syenites. A number of modal analyses have also been taken from tables (Johannsen, 1952) and plotted, and it will be seen that the monzonites mostly fall within the area between 40 and 60% of orthoclase, whereas the Snowy Mts. rocks bear some relation to the tonalites, syenogabbros, diorites and dioritic dyke rocks. Fm @ Syenogabbro 2 Snowy Mountains Rocks (Johannsen,1952,127) Ti Diorite 4 Mt Dromedary Monzonites (Johannsen,1952,154) Dioritic Dyke Rocks © Tyrol Monzonite (Johannsen,1952,193) @ Tonalite A Monzonites (Johannsen, 1952,173) (Johannsen, 1952,110) P Pl Text-fig. 6.—Triangular diagram showing relative proportions of orthoclase, plagioclase and ferro-magnesian minerals in a number of Snowy Mountains rocks and some types from elsewhere. Because of the marked monzonitic fabric, of the presence of fairly basic plagio- clase and of the fairly persistent presence of pyroxene, the name monzonite is retained for those types that contain readily recognizable orthoclase and a well marked monzonitic fabric. Hornblende-pyroxenite ——> Hornblendite AN ro : \ Dolerite ae Hornblende -Porphyrite paola te pA fHormblenge-Porshyrt te Diorite -Porphyrite Orthoclase-diorite | er baa -Porphyrite Monzonite ae Mica-Lamprophyre It is evident that these rocks are all related in space and in time and thus they might be said to belong to a petrological province. Although the monzonites are not commonly considered as normal members of the granodiorite stem, and by some are regarded as belonging to a separate magma type, where monzonites may occur, together with latites, in a distinct petrological province (Brown, 1930; Hanlon, Joplin and Noakes, 1952), the literature nevertheless reveals that they are not infrequently associated with diorites and with syenites in many parts of the world. In referring to the Predazzo and Monzoni occurrence, from which the monzonites take their name, Shand (1949) pointed out that a number of rock types occur together and he discussed a hybrid origin. 6. ORIGIN OF THE BASIC ROCKS. The origin of the basic and ultrabasic rocks of the Tumut Pond area is a little obscure, and three possibilities suggest themselves: (1) they are original sills interbedded with the sediments and bear no relation to the contiguous granite ; (2) they are earlier differentiates of the granite magma; (3) they are products of assimilation, one parent being granite, and the other either a basic rock or a calcareous sediment. Reference to Fig. 1 will show that they are in very close proximity to the eranite and the same relation exists further north (Vallance, 1953), so it seems that their association with the granite is not a fortuitous one, as suggested by (1). Differentiation versus Assimilation. Unfortunately the field evidence throws little light on the problem though in the ‘‘ Diorite ”’ quarry at Locality G., where good exposures are available, some intrusive relations are evident and some order of succession can be established. Elsewhere, however, and indeed in many places within this quarry, types appear to grade one into the other as though large blocks of more basic material were completely surrounded by less basic; the petrography supports this field observation. It is also of interest to note that Vallance (1953) in describing the Adelong norite, which he compares with the Kiandra monzonite, remarks upon the presence of basic clots enriched in olivine and pyroxene that appear to be closely related to the host rocks. Cc 136 GERMAINE A. JOPLIN. Although some contacts have been observed, and a magmatic origin for at least some of these rocks is beyond dispute, the capricious distribution of the component minerals also suggests partial assimilation of solid material by a magma. Furthermore, the development of large hornblende crystals in the hornblende-pyroxenites and the segregation of such crystals to form patches of hornblendite are reminiscent of the Ach’uaine Hybrids of Sutherland (Read, 1931), and similar observations have been made among hybrid rocks by Deer (1938) and by Joplin (1939). Many of these rocks, particularly the monzonites, show excellent examples of a discontinuous reaction-series, and in fact the Kiandra rock was used for many years in the Department of Geology, University of Sydney, as an illustration of Bowen’s Reaction Principle. Bowen (1922 a and 6) discussed this principle with reference both to differentiation and to reaction between acid magma and solid basic material. In a normal differentiation series it would be unusual for a complete sequence of discontinuous reaction minerals to be present in a single specimen, yet such is the case in many of the monzonites. If this took place during differentiation, it would suggest great and sudden variations of temperature during cooling, whereas it could be regarded as fairly normal in the case of solid material that was undergoing both mechanical and chemical assimilation in an acid magma. Zoned plagioclase, though present in most rocks, is not the continuous type that might be expected in a differentiation series. A rapidly fluctuating temperature might explain this too, but it would not explain the fact that a plagioclase of intermediate composition normally surrounds the zoned crystals. Such an arrangement, on the other hand, can be explained readily by assimilation. The basic, somewhat altered cores of labradorite represent the original felspar of the basic parent, the fresh oligoclase rims represent the phase which is being deposited by the magma at the time of incorporation of the basic material, and the surrounding andesine has formed as a result of some assimilation and has been deposited later from a basified magma. Although a monzonitic fabric may develop during the course of crystallization from a differentiating magma, it is a fabric that might well be expected in a rock of hybrid origin, especially when the amount of orthoclase and of quartz shows such marked variation. Further reference to Table IV will show that although it has been arranged in order of decreasing orthoclase, there is no corresponding regular gradation in the volume percentages of other minerals; this again is a departure from a normal differentiation series. In Table IT three modal analyses of diorites and one of hornblende-gabbro are compared. Unfortunately this is an insufficient number of analyses upon which to base conclusions regarding origin, but it is evident that the volume percentages show some regular gradation, and there appears to be more evidence of differentiation here than among the orthoclase-bearing types in Table IV. Diorites of doubtful origin have been found among the Ach’uaine Hybrids and Read (1931) has pointed out that they have some resemblances to the intermediate type of Ach’uaine Hybrid and are probably related. Although the origin of the Snowy Mts. diorites is also doubtful, they are most certainly related both to the ultrabasic rocks and to the monzonites. Thus the weight of evidence seems to favour assimilation rather than differentiation for the origin of these rocks, and if such is the case then the nature of the basic parent must now be considered. Nature of the Basie Parent. As indicated above (p. 121), two types of basic magma appear to have antedated the granite at Cooma. One, related to a norite, has given rise to ultrabasic types and is itself metasomatized by the granite (Browne, 1914; ee c BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND. 137 Joplin, 1939, 1942), and the other, a basic granulite, appears to have affinities to the Porphyritic Central Magma type, and is found only as inclusions within the granite (Joplin, 1942); furthermore, recent work (Walker and Joplin in MS.) suggests that some of these basic granulites may be of sedimentary origin. Although neither of these types is known to crop out in the Tumut Pond—Happy Jacks area, either may occur among the deeper-seated rocks and must be considered as a possible parent of the hybrids. @ 1 - 10 and 14 @ 11 -13 A 15 - 20 He 22 - 26 Text-fig. 7—AFC diagram showing fields for Porphyritic Central Magma type, magnesia-rich amphibolites at Cooma and Snowy Mts. and Adelong rocks. 1. Pyroxenite, Locality K. 15. Basic xenolith, Murrumbucca. 2. Altered monzonite, Locality G. 16. Hornblende-granulite, Cooma. 3. Orthoclase-bearing diorite, Locality G. 17. Amphibolite, Adelong area. 4. Altered monzonite, Locality G. 18. Hornblende-pyroxene granulite, Cooma. 5. Altered monzonite, Locality G. 19. Basie xenolith, Murrumbucca. 6. Orthoclase-bearing diorite or monzonite, 20. Basie xenolith, Murrumbucca. 2 Locality G. PA Coarse phase of heterogeneous amphi- 7. Quartz-bearing olivine-monzonite, Kiandra, bolite, Cooma. Locality A. 22. Amphibolite (relict gabbro), Cooma. 8. Monzonite-Porphyry, Kiandra, Locality A. 23. Fine-grained granoblastic amphibolite, 9. Norite, Adelong. Cooma. 10. Kersantite, Adelong. 24. Ultrabasic inclusion, Adelong area. 11. Pyroxene-granulite, Hume Weir, Albury. 25. Tremolite-chlorite schist, Cooma. 12. Altered basic rock, Hume Weir, Albury. 26. Fine phase of heterogeneous amphibolite. 13. ‘‘ Trachytic ’’ rock, Albury. 14. Xenolith in equilibrium with granite, Cooma fall into two well-defined separate fields. Murrumbucca. Again there is little doubt that the hybrids are very closely associated with the pyroxenite, which appears to have a magmatic origin since a mass of it occurs as a small irregular intrusion with sound contacts at stations 506+-70 to 508 +50 in the Eucumbene-Tumut Tunnel. in a discussion on the ancestry of the hybrids. It was shown on an AFC diagram (Joplin, 1942) that the basic rocks at Thus this too must be considered These have been re-plotted in Fig. 7, and the field for the magnesia-rich type extended to include two ultra- F 138 GERMAINE A. JOPLIN. basic rocks, one from the Cooma area and one from Wantabadgery to the north- north-west (Vallance, 1953). Basic rocks from the Snowy Mts. region, from the Adelong area 34 miles north, and from the Albury district about 150 miles west, are also plotted, as well as several xenoliths from the Silurian granite north of Cooma. It is clear that these occupy a separate field which is distinct from the other two, but which slightly overlaps them. It was suggested (Joplin, 1946) that the three basic rocks from Albury might compare with the pyroxene-granulites of Cooma, but it is now apparent that they fall into a smaller separate field and resemble the Snowy Mts. types more closely than the Porphyritic Central Magma type with which they were originally compared. Points 15 and 19 are the plots of basic xenoliths in the Silurian granite on Murrumbucca Creek, north of Cooma, and it is obvious that they are related to the granulites, whereas point 14, which is a xenolith in almost complete equili- brium with the granite, occupies a position in the same field as the Snowy Mts. basic rocks. If it can be assumed that this xenolith had an original composition similar to those represented by points 15 and 19, then it can be suggested that the Snowy Mts. basic rocks have arisen from a magma much hybridized by the incorporation of material similar to the Cooma granulites and possibly related to the Porphyritic Central Magma type or to a highly metamorphosed calcareous rock. Unfortunately the identity of the xenolith (point 14) is uncertain, so this inference cannot be made with any confidence. Point 1 represents the analysis of a pyroxenite with which these rocks are undoubtedly associated in the field. It falls within the area arbitrarily delineated for this group of rocks, and appears to differ widely from the two ultrabasic rocks 24 and 25, which are associated with the more magnesia-rich type of magma. The fact that this ultrabasic rock contains greater C and A relative to F on the AFC diagram suggests that it represents a distinct ultrabasic magma, that it is an ultrabasic differentiate of the Porphyritic Central Magma type, that it is a differentiate of some other magma unknown in the Cooma area, or that it is a metasomatized calcareous rock. Unfortunately there is no means of solving this problem, but two observations are pertinent, namely, the relatively small amount of pyroxenite and the suggestive positions of points 14, 15 and 19 on the AFC diagram. The limited amount of pyroxenite and its persistent association with the other basic rocks strengthen the view that it is a differentiate rather than a separate ultrabasic magma, whilst its position on the diagram relative to those of the three xenoliths, and its close field relation to the gabbros, lend slight support to the view that it is a differentiate of the Porphyritic Central Magma type. Although hornblende is present in most of the rocks described in this paper, it is noteworthy that pyroxene is a prominent mineral, and that much of the hornblende is either pseudomorphing or moulded on to original pyroxene. Pyroxene is the typical ferromagnesian mineral of the basic extrusives and of the intrusives associated with the stable areas of the crust, while hornblende is more common in the granitic complexes of the geosynclines, where hornblendites are typically developed and where pyroxenites are rare. For this reason the writer has some hesitation in suggesting that the pyroxenite is genetically related to the Silurian granite. On the other hand, pyroxenites are not unknown as associates of the Porphyritic Central Magma, a magma characterized by the presence of pyroxene. The essential minerals of rocks belonging to the Porphyritic Central Magma type are basic plagioclase, augite and iron ores. This magma is distinguished by the early separation of basic felspar, thus the normal basic differentiate is an anorthosite, though veins of pyroxenite are recorded in the Great Eucrite Ring-dyke of Ardnamurchan (Richey and Thomas, 1930). There is some evidence that such a magma gave rise to small sills or flows in the Cooma BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND. 139 area, so it is not unreasonable to assume that a series of slightly larger differentiated sills occurred at some depth below the present level of erosion in the Snowy Mts. area. The Hybridization Process. In a few places the basic rocks have been altered by the granite and, with the exception of the lamprophyres, there is little doubt that they antedate most of the granites in the Snowy Mts. area. Furthermore, their marginal disposition to the (?) Silurian granite suggests that they are related to it and probably belong to the same orogeny. If a hybrid origin is postulated the granite is the likely acid parent, and assimilation must have taken place at a deep level before the emplacement of the granite at the present level of erosion. If such an assumption be made, then at this level the granite magma, or partial magma, would have sufficient energy to completely assimilate deep-seated basic rocks consisting of pyroxenites and gabbro by a process of reaction. Thus a basified acid magma, containing fragments with which it was in complete equilibrium, might be emplaced at higher levels as a diorite. It is probable that larger fragments, which had failed to attain equilibrium, would also travel upwards with this magma and occur within it as partly resorbed xenoliths of pyroxenite or gabbro. Possibly at a higher level and a slightly later stage, other sills of the gabbro and pyroxenite were invaded by solutions containing silica and alkalies arising in advance of the main granite intrusion, and these would produce both ortho- clase-mica-diorites and monzonites. At this higher level the energy, and possibly the time, was insufficient to bring about complete equilibrium, and thus there is a more complete discontinuous reaction-series exhibited by these rocks than by the diorites that formed at a deeper level. Nevertheless, there was still sufficient energy to bring about a fairly complete mechanical disintegration, and sufficient liquid phase for the material to move upward as a mobile mass to be injected at the present level of erosion. It seems likely that the rise of the granite followed closely upon that of the monzonite, and that accompanying volatiles were responsible for the formation of large hornblende crystals in situ among rocks of appropriate composition, thus forming hornblendites and hornblende-gabbros. Shortly afterwards, when the granite and basic hybrids that had been emplaced at the present level of erosion were essentially solid, there was a discrete injection of small dykes and veins of lamprophyre, porphyrite and dolerite. These are highly altered rocks, and it is obvious that carbon dioxide played an important role in their formation. It seems likely that they were derived from a deeper level of hybrid magma and subjected to hydrothermal action at the end stage of the consolidation of the granite after emplacement. Reference to Table III shows that two of the altered orthoclase-diorites or monzonites (Anal. IV, V) contain higher potash than the two fresh monzonites (Anal. VI and VII), yet if the corresponding modes be compared (Table IV, Nos. 8, 9, 10, 2 and 1), it will be seen that the orthoclase and biotite content is much lower in the altered rocks and in fact bears no relation to the amount of potash present. It may be further noted that the altered rocks contain lower silica and higher alumina as compared with the fresh monzonites, and though this may be due to alteration it seems more likely that the altered rocks were more closely allied to the orthoclase-diorites and originally may have been more basic than those analysed (Table IIT, I and II), there being an addition of silica and of potash at a late stage, which caused sericitization of the felspar and some silicification. A decrease in the amount of magnesia may imply a movement of chlorite-bearing solutions, and the increase of ferric iron relative to ferrous iron further suggests alteration. In the field the pink rock shows an intrusive 140 GERMAINE A. JOPLIN. front against the orthoclase-diorites, and it seems fairly obvious that this is brought about by an invasion of hydrothermal solutions that have not only brought in potash and silica, but have brought about alteration and movement of many of the components of the rock. This possibly took place during the last stage of the cooling history of the granite, and perhaps slightly later than or approximately at the same time as the discrete injections. This study is not sufficiently detailed to permit further elaboration of these processes, and these suggestions are put forward only as a tentative explanation of the origin of this interesting and complex group of rocks. An attempt is made to indicate their origin schematically below. Granite Magma Porphyritic Central n Magma x nl 3 5 3 Bey > s Hornblende » Veins © Pyroxenite Hornblendite a Hornblende- = pyroxenite _ a Gabbro rnbdlende- gaobro Mica-lamprophyre Monzonite Hybrid magma __ Mica-porphyrite with much solid Dolerite Diorite Hybrid magma Hornblende - lamprophyre aS Dolerites Orthoclase-bearing diorite REFERENCES. Andrews, E. C., 1901. ‘‘ Report of the Kiandra Lead.”’ Geol. Surv. N.S.W., Min. Res, 10, 17. Bowen, N. L., 1922a. ‘‘ The Reaction Principle in Petrogenesis.”’ Journ. Geol., 30, 177-198. ——_—____——— 1922b. ‘‘ The Behaviour of Inclusions in Igneous Magmas.”’ Ibid, 513-570. Brown, I. A., 1930. ‘‘ The Geology of the South Coast of New South Wales, III. The Monzonitic Complex of the Mount Dromedary District.” Proc. Linn. Soc. N.S.W., 55, 692. Browne, W. R., 1914. ‘‘ The Geology of the Cooma District I.’’ Turis Journat, 48, 172-222. —_____—— 1944. ‘“‘ The Geology of the Cooma District II.”’ Ibid, 77, 156-172. and Greig, W. A., 1923. ‘‘On an Olivine-bearing Quartz-Monzonite from Kiandra.”’ Ibid, 56, 260-277. Deer, W. A., 1938. ‘‘ The Composition and Paragenesis of the Hornblendes of the Glen Tilt Complex, Perthshire.” Min. Mag. Lond., 25, 61. Hall, L. R., and Lloyd, J. C., 1954. ‘‘ Snowy Mountains Area Progress Report I, Toolong.”’ Dept. Mines, N.S.W., Ann. Report for 1950, 98-99. Hanlon, F. N., Joplin, G. A., and Noakes, L. C., 1953. ‘‘ Review of Stratigraphical Nomen- clature. 2. Permian Units in the Illawarra District.””’ Aust. Journ. Sci. 15 (5), 160-163. Harker, A., 1919. ‘‘ Petrology for Students,’ Cambridge, 46. Harper, L. F., 1916. ‘*‘ The Adelong Goldfield.” Geol. Surv. N.S.W. Min. Res., 21. Iddings, J. P., 1913. ‘Igneous Rocks,” Vol. II. New York, 200. Johannsen, A., 1952. ‘‘ A Descriptive Petrography of the Igneous Rocks,” Vol. IIT. Chicago, 110, 127, 154, 173, 193. BASIC AND ULTRABASIC ROCKS NEAR HAPPY JACKS AND TUMUT POND. 141 Joplin, G. A., 1939. ‘‘ Studies in Metamorphorism and Assimilation in the Cooma District of New South Wales. I. The Amphibolites and their Metasomatism. TxHis JOURNAL, 73, 88-106. 1942. ‘* Petrological Studies in the Ordovician of New South Wales. I. The Cooma Complex.” Proc. Linn. Soc. N.S.W., 67, 156-196. ——__—_—_—_— 1943. “Idem. II. The Northern Extension of the Cooma Complex.” Jbid, 68, 159-183. ——__—___——_ 1947. ‘“‘Idem. IV. The Northern Extension of the North-east Victorian Complex. Ibid, 72, 87-124. Nockolds, S. R., 1954. ‘‘ Average Chemical Composition of Some Igneous Rocks.” Bull. Geol. Soc. Amer., 65, 1007-1032. Read, H. H., 1931. ‘‘ The Geology of Central Sutherland.” Mem. Geol. Surv. Scot. 165-172. Richey, J. E., and Thomas, H. H., 1930. ‘‘ The Geology of Ardnamurchan, North-west Mull and Coll.” Mem. Geol. Surv. Scot., 86-87. Shand, 8S. J., 1949. ‘‘ Eruptive Rocks.” London, 275. Tyrrell, G. W., 1928. ‘‘ Principles of Petrology.’’ London. Vallance, T. G., 1953. ‘* Studies in the Metamorphic and Plutonic Geology of the Wantabadgery- Adelong-Tumbarumba District N.S.W., II. Intermediate-Basic Rocks.’’ Proc. Linn. Soc. N.S.W., 78, 181-225. Whitworth, H. F., 1954. ‘‘Petrological Determination of Specimens from Toolong Area.”’ Appendix to paper by Hall and Lloyd, Dept. Mines N.S.W., Ann. Report for 1950, 103-104. ON A FORMULA OF THE CONVOLUTION TYPE RELATED TO HANKEL TRANSFORMS. By JAMES L. GRIFFITH. School of Mathematics, New South Wales University of Technology. Manuscript received, July 15, 1957. Read, August 7, 1957. SUMMARY. Assuming that the Hankel transform is defined by ie: the formula j 2, —Va,¥ flu ya’ tt sin Yo Aas IP be taal eek with w?=2?+s?—2xs cos a, w =0 is discussed. Incidentally, the formula TS [uJ y(us) f(u) = 2 vee Ih LE) gin Y ada P(g) (v+2) 0 w is derived. I The n-dimensional Fourier Transform of a function f,(7,,. . ., v,) is defined by FilEny s+ +9 & =F [fot - - +) L,) ~ (27 rarlt a UNS Dfo(y : @,,)AX, sel ces dz, Suet (ales) where &-7 signifies the dot product of the vectors (&,. . ., &,) and (@,,. . -, &,). The inversion formula for this transform is fo(@1) - aes) oe: Fy eau cn iene) 2) ~ (Qn Bay fie a of, ( (Gis OO) 2) hee D9) dé,,- xe (1.2) It is well known that if f,(7,,.. ., 7,)=fo(7) where roar. eles RAE Ge ene (1.3) then the equation (1.1) reduces to emante=[ Ped xy, 1 (OT) Tig OT whole pet (1.4) 0 CONVOLUTION TYPE RELATED TO HANKEL TRANSFORMS. 143 where f,(e)=f,(&1,- - -» &,) and or =F ee Ne A aiaus (1.5) With this modification, Bane on reduces to rinrpgry= [* Bueno —yale)ide “sssms.e< (1.6) 0 The convolution formula connected with the transform (1.1) is i ice) co ie earl. : [fale Yip + + ey U, Yn )9(Y 19 Cae oh Yn )dY1) egal | ay,| ssf ( Gastemen ey oma Cage ay Ce) ot nd son wat tasl wins Spa (1:7) Tf fo(t1,. - +» @,)=folr) and go(%,. . -, %,)=9)(7r), this equation reduces to 91—4n oe) Tw Se 2-1 gyjnn—-2 Plrarae sp], |, {iste sine o an] =F (ON GmG) a elses ai wits oensts ee. cyatl algae (1.8) where W2=r?-+s2—2rs cos a. We now make the substitutions rin—1f(r)=f(r), ri’ —199(7) =g(r) eo =F(e)=Kle)s, oe” 19,(e)=G(e) =2v-+2, r=, p=4, and obtain = ABC) lnn Pepa a eaten CRs Gini a se chee cdl w aie wn wees (1.9a) fla)=[~ wIy(ucr)fu)du 0 =e | ERR a 6 oi btero dled itiiais 2 3083 (1.90) an r, anne 5 a eae te f(w)g( olde gin2’ a ads] (3) VG eee ee ee ce (1.10a) where w?—«? +s? 2as COS &. Equation (1.10a) can be interpreted as either Dia f(w)g(s)s’t1 sin?’ a Se l+v Jv Py Tre nl, BL TYI¥ (OU a I. “dads wy AUN G(s = cde wiysh os Sas (1.100) or as | u—»f(u)g(u)J,(au)du 0 2a" © (™ f(w)g(s)s¥t1 sin2’ « =rprosn), |, — Gods we eet en A (1.10¢) 144 JAMES L. GRIFFITH. Referring to the diagram which needs no description, it is easily seen that the equation (1.10a) may be written in the symmetrical form wna =P. rere TA) f(w)g(s) sin” & sinv ed) (1.10d) where the integral is taken over the upper half plane. The formal work of this section suggests that formule (1.10) hold only for v=dn—1 (n=an integer 21). We will prove two cases in which the equations hold for all v> —}. 9 Suppose that xf(~) and x'g(x) belong to L7(0, co), then it is well known that u+f(w) and w?g(w) belong to L?(0, oc) where the integrals in equations (1.9a) and (1.9b) are to be understood to be mean-square integrals. In particular flw)= Lim. [" wJ,(eu)f(w) po 0 The Parseval formula for this transform takes the form {" af (x)g(x)de= Ik Uf (UG AL)OM sas tone (2.1) 0 If g(x) =a, 0 —3.) CONVOLUTION TYPE RELATED TO HANKEL TRANSFORMS. 145 We now find a formula for Ty '[u-vJ*(us)f(u)], s>0 and v> —} Since u-vJ,(us) is bounded, ui—vJ,(us)f(w) belongs to L2(0, ae whenever u3f(u) belongs to L(0, o). Using Watson, p. 397 (16) (somewhat modified), we find that T=" ud (us) Ty +1 (wa) f(u) ee i o Jy .1(uw)(#@—s cos «) sin?’ af(u) oa 1 2 dadu where again w?=a?+s?—2us cos «. Observing that when «4s, w=|x—s| and when w=s, w=2e sin $a, we can show that the integral converges absolutely, which allows the order of integration to be interchanged. Thus i Sk ™ (2—s Cos a) sin?’ 00 ee i ranean. ES a Jy 44(uw)f(ujdu 2 0 2 —vaovgy Tw (a —s cos a) gin2’ Oo w oe) Ee we te da yr ify)dy (from equation (2.2)). Then d 2-Ysva2y ™ 2v+1)s sin?’ a cos a (2v-+2)as2 sin2%t+2 q Geeta pd a . +1) 4 2v+2) ) (Ayr (v +4 wy +2 wy +4 j aH as? smn a sin?’ [great ay — ee 00) +E hte | 0 Ww (In order to justify the differentiation under the integral sign we observe that f(w) belongs to L1(a, b) for finite a and b, and then use the properties of w, just quoted, in conjunction with McShane, p. 217, Coroll. 39.2.) oe i d (s sin’¥*? & ae Fete x sin2 ~ 1PG)P(44) | dx were [9 fy) sae oY “flo)| aa “7 2-vgvg2v+1 T f(w) ae ae mee ae Then equation (2.3) shows that Ly *[w~T,(us)f(w)] Sey eee LL (2.4) We now replace /(u) in ia (2.1) by u-J,(us)f(u) and obtain us OTe g(x) sin?%« iy Il ee dada = I. wJ,(us)| u—f(u)g(u) Jd. 0 (the last integral being an L}-integral). 146 JAMES L. GRIFFITH. Interchanging x and s leads to era w)g(s) sin?’ « ip [- DTA tae dads =|" ud (wa) [u-f(u)g(u) du. 6. eee cece eaee (2.5) 0 We have thus proved that equation (1.10c) holds if 7?f(x) and «x?g(x) belong to L7(0, oo), the integrals being L}-integrals. 3 In this section, we will show that equation (1.10b) holds if #*f(x), x4g(«) and «x’t+!g(”) belong to Z1(0, 00). The transform in this case is defined by fee= | DIU) FONE. | onc nereateiorans (3.1) 0 Writing 2-*h(x)/T(4)0(v+4) for the right side of equation (1.10c), we will prove that x*h(«) belongs to L1(0, 0). Now i iP xttrsyt+lw- | f(w) || g(s) | sin?’ adadx On -h0 = tt |\9(s) | i | f(w) | sin’? y sin’+? « w-tadada 0 Jo =s’+1 | g(s) | I | f(w) | sinv—# y siny+? « w2dydw Ony/0 (changing the origin of co-ordinates from P to Q, see figure) =Cs*" | g(s) if w? | f(w) | dw 0 7 Tv where o= | sin’—? ydy. 0 Thus ia ip [; wh +9»+199~ | fw) |] g(s) | sin” adadads so" “ gytl | g(s) | as * w | fiw) | dw. 0 0 This indicates that the integral on the left of the last inequality converges absolutely. We may then change the order of integration to obtain the required result. Now | ie i at 1J,(xu)s**1w-f(w)g(s) sin’? adadsdx ) 0 0 =|" er eagisyas |” i LTS, (2u)w-f(w) sin?’ adadx .... (3.2) 0 0 0 CONVOLUTION TYPE RELATED TO HANKEL TRANSFORMS. (by absolute convergence) =|" srtg(ayds |” iL ew tlJ,(xu) sin?’ y f(w)dydw 0 0 Jo (changing the origin from P to Q). =—T(v-+4)T (4) wf 0 modacanoyteoye |” sJ,(us)g(s)ds 0 (recalling that #?=s?-+w?—2sw cos y and using Watson, p. 367 (16)) =QT'(vth)T(dya- fugu). oc. ccc ccc ceees (3.3) 147 Then comparing equations (3.2) and (3.3), we see that equation (1.10d) holds under the conditions stated at the beginning of this section. 4 In this section, we note two interesting applications for the case v—0. In this case the equation (1.10a) reduces to T-1Ef(u)g(u)|=" ae | flog(eieds <..2...1.. (4.1) From Watson, p. 485 (5), we find tl ara =) | ee ee (4.2) Thus ie wJo(va) (uk) Pau * i eG i cos «+k?) es hee sds =[ (s? +k?)[(s? +a? -k?)? —44s?]? 1 . an Hae rise v nen, ae al -1 — x Fae =| sinh 7a ae )+sinn 5 1 £ Sa eS sinh=! ez OK (compare with Erdelyi, p. 16 (32), where this result appears in a different form). Consider the equation ay 1 dy eas ye (4.3) Assuming that f(x) is a suitable function, we take the 7 -transform of equation (4.3) and obtain —ueg 29 —f(u) where 7, [y(x)]=g(u). Thus - 1 = Yy(u)= — ee) 148 JAMES L. GRIFFITH. Then referring to equations (4.1) and (4.2) we find the particular solution vo fT K,(kw)f(s)dods of equation (4.3). This leads to the “ general” solution of the equation in the form y(t) = Alg(ke) +BK (ker) — ~ | ‘ I * Ky (kw)fi(s)dads. 0 0 REFERENCES. Watson, G. N., 1952. ‘‘ Theory of Bessei Functions.’’ Cambridge. Erdelyi, A., and others, 1950. ‘‘ Tables of Integral Transforms.” Vol. II. McGraw-Hill. McShane, E. J., 1947. ‘“‘ Integration.” Princeton. THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. JOHN F. LOVERING. Department of Geophysics, Australian National University, Canberra. With four Text-figures. Manuscrépt received, July 29, 1957. Read, October 2, 1957. ABSTRACT. The geochemical behaviour of selected elements is discussed relative to their observed distributions between the silicate, sulphide and metal phases of stony-iron meteorites. Furthermore, the observed distribution of certain elements in iron meteorites is discussed relative to the behaviour of these elements during the crystallization of an iron-nickel melt forming the core of the parent meteorite body. INTRODUCTION. In 1937, Goldschmidt suggested an empirical geochemical classification of the elements into three groups—siderophile, chalcophile and lithophile— depending on whether the elements tended to concentrate in either metal, sulphide, or oxide -+-silicate phases, respectively. As a basis for his classification, Goldschmidt used the data available on the observed distributions between the metal, sulphide and silicate slag phases forming in metallurgical processes as well as data on the distributions of elements in iron meteorites, troilite (Fe S) from both stony and iron meteorites, and the silicate portion of the stony meteorites. Many of the data on distributions in meteorites which were available to him are now considered to be of rather dubious reliability. Furthermore, it now seems most unlikely that the silicate, sulphide and metal phases of chondritic stony meteorites were ever in equilibrium with regard to the distribution of trace elements, since all indications are that these meteorites are essentially consolidated aggregates of all three phases (Lovering, 1957, b & c). It is not surprising, then, that Goldschmidt’s geochemical classification of the elements (see Goldschmidt, 1954) has not always accorded with the behaviour of elements predicted from their thermodynamic and atomistic properties. The only primary meteorites known in which silicate (+oxide), sulphide (+phosphide) and metal phases exist and in which the distribution of elements can be taken as representing equilibrium distributions at temperatures of up to 2000° K and of between 104 and 10° atmospheres are the stony-iron meteorites (Lovering, 19576). Of these the pallasites are by far the most common (70 per cent. of the total number) and are composed of olivine crystals (of composition about forsterite 80: fayalite 20) and very minor oxide (magnetite and probably chromite) phases embedded in a base of iron-nickel alloy (about 11 per cent. nickel) with troilite (FeS) and some schreibersite (Fe,P). Olivine and metal each make up about 50 per cent. by weight, while troilite and schreibersite together make up about 1 per cent. From observed phase relationships and from data given by Perry (1944), the order of crystallization is probably olivine, metal, troilite and schreibersite. Recent work by Goldberg, Uchiyama and Brown (1951), Patterson, Tilton and Inghram (1955), Lovering, Nichiporuk, Chodos and Brown (1957), and Lovering (1957, a & c) has provided analytical data for the silicate, sulphide and metal phases of pallasite meteorites from which the geochemical behaviour of the elements Mg, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Ga, Ge, Pb, can be determined. 150 JOHN F. LOVERING. A measure of the lithophilic versus chalecophilic behaviour of an element in these meteorites is given by the massaction constant, C,, for the reaction M Silicate +FeS =MS +Fe Silicate where M is any metal and from which (M)suipniae( Fe) siticate C, -(Fe)sutpniae(M)siticate Thus elements for which C, is >1 have stronger chalcophilic tendencies in this environment while elements for which C, is <1 have stronger lithophilie tendencies. TABLE [. Trace-element Distribution Between Olivine (Silicate), Troilite (Sulphide) and Metal Phases of Pallasites and the Geochemical Behaviour of Some Elements in Meteorites. Concentration (ppm) in B| a aio Geochemical Behaviour. , the Constituent Phases of 2 Is id is = Pallasites. SiS or-1 © sg S\2 | Gold- This Work a SIS = schmidt (based on a Olivine.* | Troilite.+ | Metal.t IL Ir (1954). |C, and C.). S o | Mg 27-8% ~0-0038% —— 0- 00002 — L L>C>8 Ti 25 ~2 ea 0-012 <0-4 (©) L>C>S8 Vv 15 10 << 0-097 <0-07 Chae L>C>8 Cr 150 1100 ~2 1-1 <0-002 Cy C0, L>s Mn 1900 320 <5 0-025 0-011 C, L L>C>8 Fe 92306 63-6% 885% 1 1 8, C Cas Co 35 160 5500 0-67 25 S$, 1(L)) |, S=ise Ni 0:025% 0-6% 11°-0% 3:5 13 8, [(L)] S>C>L Cu 4 700 200 26 0-21 C Cc>S8S, L Ga <2 ~0°-4§ 18 > 0-03 32 C, (L) S>C, L Ge <20 8 40 > 0-06 3:6 ) S>C, L Pb <10 ~15] ~0:37F |>0:2 0-018 C, (S) C>S8, L * Data from Lovering (19576 and c). + Data from Lovering (19576) unless otherwise stated. { Data from Lovering et al. (1957) unless otherwise stated. L=Lithophile ; C=Chalcophile ; S=Siderophile. § Troilite from Iron Meteorites [Goldberg et al, (1951)]. {| Phases from Iron meteorites [Patterson et al. (1955)]. C>(C)>[(C)]. A measure of the chalcophilic versus siderophilic behaviour of an element in these meteorites is given by the mass-action constant, C,, for the reaction MS+Fe=M+FeS from which (M)metai(F'e)sutpniae (Fe) metai(M)sutpniae Ce Elements for which C, is>1 have stronger siderophilic tendencies in this enrivonment while those for which C, is<1 have stronger chalcophilic tendencies. The geochemical behaviour of the elements as listed in Table I has been calculated from the relative values of C, and C,. Goldschmidt’s (1954) geo- chemical classification is also included in Table I. THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. 151 In Part I of this paper an attempt is made to explain the observed geochemical behaviour of the elements in meteorites from both thermodynamic and atomistic viewpoints. Part II is concerned with the behaviour of certain siderophilic elements during the crystallization of the metal core of the parent meteorite body from which the various iron meteorites have originated (Lovering, 1957a). Part I. THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN PALLASITE METEORITES. THERMODYNAMIC APPROACH. The distribution of elements between the three phases is governed by reactions of the type : M-+Fe silicate =M silicate +Fe M-+Fe sulphide=M sulphide + Fe. TaBLeE II. Standard Free Energy of Formation (AF°) of Some Oxides and Sulphides, After Rankama and Sahama (1950) and Goldschmidt (1954). (kg. cal. per gm. Atom Oxygen|/Sulphur at 25° C). —AF° —AF° —AF° MgO 136-4 ZnO 76-3 Zn8 40-4 Al,O; 125-6 SnO 60-8 FeS 23-4 V.O3 103-7 FeO 59°6 PbS 22-7 TiO, 102-5 NiO 51-7 NiS 21-3 MnO 91-3 PbO 45-1 Cos 21-1 Cr,0, 84°5 Cu,O 29°5 Cu,S 19-2 Ga,O; 78-3 In,O, ers Cus Ls Ags 87, Thus a knowledge of the free energies of the various metal silicates and metal sulphides, in relation to those of iron silicate and iron sulphide, would enable predictions to be made of the geochemical behaviour of the elements. Unfortunately, few free energy data are available for metal silicates and free energy data for the metal oxides are generally used instead. Goldschmidt (1954) and others have stated that the following general relationships hold : Lithophile elements —AF°gement oxiae — —AF°reo Chalcophile elements —AF°gement sulphide => —AF res Siderophile elements —AF °.jement sulphide << —AF “res where AF cement oxide/sulphide 1S the standard free energy of formation of element oxide/sulphide per gram atom of oxygen/sulphur. From Table II it is apparent that the free energy data do not explain the observed behaviour of all the elements. For example, Ga, Zn and Cr should be lithophilic, but their observed behaviour would indicate they are either chalcophilic or siderophilic. Similarly, Cu, Pb and Ag should be strongly siderophilic but all are actually chaleophilic. Rankama and Sahama (1950) have suggested that the anomalous behaviour of Ga and Zn may be due to their distribution being not controlled by the thermodynamic properties of their pure dD 152 JOHN F. LOVERING. compounds (because of their low concentrations and subsequent inability to form pure compounds) *‘ but by the energy balances connected with the corresponding isomorphic substitutions.” Most workers have pointed out that discrepancies between observed and calculated behaviour of elements from free energy data are only an approximation since metal oxide rather than metal silicate data have been used. The present writer would like to suggest that an even greater source of error lies in the use of free energy data for metal oxides and sulphides in which the metal is present in an oxidation state which is different from that in which it occurs in the meteorite environment. Thus it is important to establish in which oxidation states the elements are most likely to occur in the environment in which the pailasite meteorites crystallized. Oxidation Potentials and the Oxidation States of Elements in the Meteorite Environment. In aqueous solutions, oxidation/reduction potentials may be used to indicate the stable oxidation state of an element relative to that environment. Although it is recognized that oxidation potentials are not unreservedly applicable, in the absence of other data they probably can be used to provide some information concerning the stable oxidation states of elements in the ionic and metal melts of the meteorite environment. In order to take some account of the change in environment from aqueous solution to the ionic and metal melts of the meteorite environment, it will be arbitrarily assumed that oxidation potentials for likely reactions must differ by +-0-2 volts from the oxidation potential of the limiting reaction which is taken to be characteristic of the particular environment under discussion. The history of pallasites is such (Lovering, 1957b) that two stages in their crystallization are clear, and each must be considered separately when discussing the distribution of elements between the metal, sulphide and silicate phases during crystallization. Stage 1: At temperatures around 2000° K and pressures about 104-105 atmospheres (Lovering, 1957b), olivine crystals became enmeshed in a melt of iron-nickel metal in which sulphur and phosphorus were also distributed. The elements present in this system would then distribute themselves between the silicate phase and the metal-+-sulphide phase. Metals migrating into the silicate environment would form cations whose oxidation states were controlled by the oxidation potential (E,) of the reaction Fe?+=Fe3+ +e E°—0-771 volts. From the assumptions made above, the stable oxidation state for any metal in the silicate phase is given by the form on the left-hand side of reactions for which the oxidation potentials are greater than 1-0 volts and on the right- hand side for reactions for which EK, are less than 0-6 volts. For reactions with E, values between 0-6 and 1-0 volts, it is not possible to differentiate between the two lowest oxidation states given in these reactions. The E, values of a number of oxidation reactions of interest to this discussion are given in Table ITI. Similarly, the stable oxidation states within the iron metal sulphide melt will be controlled by the E, value for the reaction : Fe+S=-=FeS +2e E,= —1-00 volts. Using these data, the stable oxidation states for certain elements in the two phases can be calculated and have been listed in Table IV. The information in Table IV may be used to a limited extent to explain the observed geochemical behaviour of elements in meteorites. For example, THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. TABLE III. Oxidation Potentials of Some Reactions of Geo- chemical Interest. (Data from Latimer, 1938). Co2+ =Co3+ +e Pb?2+ =Pb!+ +26 Au =Aut+ +e Mn?2+=—Mn3++e Au =Aut + 3e Au#+ = Aut +e Aut =Au?++e Fe?+ =Fe3+ +e Cu =Cut +e Cu =Cu?+ +2e Cut =Cu?+ +e H, =2Ht +2e Fe =Fe*+ +3¢e Pb =Pb?++2e Vt+ =V3+ +e Ni =Ni?+ +2e Co =Co?+ +2e Ti2+ =Tit+ +e Cr?+ =Cr*+ +e Fe =Fe?+ +2e Ga =Ga?+ +2e Ga =Ga'+ +3e Ga?+ =Ga+ +e Cr =Cr*+ +3e Cr =Cr?+ +26 [s7-+Fe=Fe8 +20 Mn Vv Di Mg =Mn?+-4 2e =V?+ +26 =Ti*+ +2e = Mg?+ + 2e E® (v Leith eeeill emt anal ell lll ool AV TABLE Iv. olts) 842 Stable Oxidation States within Various Phases during the Crystallization of the Pallasite Meteorites. Stage I. Stage IT. Silicate. Iron + Sulphide Metal. Sulphide (FeS) Melt. Au Au Au Au Ga3t+ Ga (Ga)(Ga?+) Ga Co?+ Co (Co)(Co?+) Co (Cu)(Cu?+) Cu Cu Cu Crs+ (Cr)(Cr?+) (Cr2+)(Cr3+) (Cr)(Cr2+) Mn?+ (Mn)(Mn?+) Mn?+ (Mn)(Mn?+) Tis+ 4oiGa (Ti?+)(Ti3+) Mier V3t+ V2t V2t+ Vit Mg?+ Mg?+ Mg?+ Mg?t+ Ni?+ Ni (Ni)(Ni?+) Ni Pb2t+ Pb Pb Pb 154 JOHN F. LOVERING. cations which can replace either Fe?+ or Mg?+ cations in the olivine lattice could be lithophilic in their geochemical behaviour. The main criterion which re- placing cations should satisfy is the well-known generalisation of Goldschmidt that their ionic radii should not exceed about 15 per cent. of the radius of either Fe?+ or Mg?+ ions. The relationship of the size of a number of cations to the size of Fe2+ and Mg?+ cations is illustrated in Figure 1. Increasingly lithophilic Increasingly chalcophilic s siderophilic a + %, re) Vv 3 8+ C96) i“ Ge = ao) 2 = re) c } On Y 3 AZ, 2 = ~ 2 ray ' 47 a — —_— am fo) 2 2 5S) .= g¢ ay Y 6 6 0 20 30 40 50 lonization Potential W Text-fig. 1.—The relationship of ionic radius and ionization potential for a number of cations. Monovalent (full triangles) ; divalent (open circles); trivalent (full circles) ; tetravalent (open triangles). Some off-scale cations: Pb?+: r=1-20, I=15-05. ver : r=0-88, [=—14-2. Si#t = r=0-53, 1=4557 Returning to specific examples of behaviour of elements in the silicate environment in meteorites, gold is present in the zero oxidation state and is consequently not likely to be a lithophilic element. On the face of the available evidence at this point Ga, Cr, Ti, V, Mn, Co, Cu and Ni may all possibly be lithoplilic elements. Both Ga’+ and Cr*+ may capture a Mg?* site in the olivine lattice, while Ti?+ and V%+ may capture an Fe*+ site. Similarly, Mn?+ may be camouflaged in an Fe?+ site, as may Co?+, Cu?+ or Ni?* in either Fe*+ or Mg?* sites. However, Ringwood (1956) has recently shown on other grounds that nickel appears to enter common olivine at the expense of iron rather than magnesium. Stage 2: With further cooling of the metal-+sulphide melt, two distinct and immiscible phases—metal phase and FeS phase (troilite)—separate out. The elements which were concentrated in the metal--sulphide melt during stage 1 must now distribute themselves between these two separate phases. Within the Fe S phase, the stable oxidation states of the elements will be governed by the oxidation potential range of -+-0-2 volts about E, for the reaction Fe+S==FeS +2e E,= —1-00 volts THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. 155 as previously given. Within the metal phase, the stable oxidation states will be governed by the oxidation potential range of +0-2 volts about E, for the reaction Fe=Fe?+ +2e E,= —0-44 volts. The most likely stable oxidation states of certain elements in both metal and Fe S phases are listed in Table IV. When cations of the elements Au, Ga, Co, Cu, Ni, Pb in oxidation states greater than zero enter the metal-+sulphide melt, they are immediately reduced to the metallic state (oxidation state zero) and thus could well be siderophilic elements. On the other hand, both Ti and Mg can exist only in the +2 oxidation state in the same environment, and thus both might be either chalcophilic or lithophilic elements. The data for Cr and Mn are not so conclusive, since both zero and +2 oxidation states may well be stable in this environment. Even more conclusive evidence concerning the geochemical behaviour of certain elements arises from an inspection of their stable oxidation states in both the metal and sulphide phases. For example, Ga, Co and Ni may possibly occur in either the zero or the +2 oxidation states in the metal phase, but only the zero state is possible in the FeS phase; consequently, all three should be siderophilic elements, as has been observed to be the case. Also, Cr, Mn, Ti, V and Mg exist in oxidation states other than O in the metal phase; thus these elements should not show siderophilic characteristics. This is in agreement with their observed behaviour (Table I). However, Cu and Pb should exist as native metals in both metal and FeS phases, and thus should show siderophilic tendencies. From Table I it appears that both Cu and Pb are more likely to be chalcophilic than lithophilic in character. In the case of Pb, the explanation may be due to the large size of the Pb atom (12-fold co-ordination radius 1-746A) compared to the size of the Fe atom (1-260A) which it should replace during crystallization of the metal phase. The Pb may originally have concentrated in the metal-+sulphide melt relative to the silicate phase, but as the metal crystallized before the sulphide phase, the Pb was rejected from the crystallized metal phase and forced to concentrate in the still molten FeS melt. Such an explanation would not apply to Cu, whose radius (1-17A) is essentially identical with that of Fe. The geochemical behaviour of the elements in the pallasite meteorites is not completely explained by oxidation potentials, but some indication is given of stable oxidation states within the various phases of the pallasite meteorite environment. Ionization Potentials and the Geochemical Behaviour of Elements in Pallasite Meteorites. It has long been recognized that since the type of bonding characteristic of the silicate, sulphide and metal phases is significantly different, then the measured tendencies of elements to form certain bond types should be valuable in providing a theoretical basis for the geochemical behaviour of the elements in these various phases. Inthophilic-Chalcophilic Tendencies. We will confine our attention first to relative distributions between metal/ non-metal compounds (i.e. the silicate and sulphide phases). There is general agreement that bonds in sulphide minerals are dominantly non-ionic (2.e. covalent), and that in silicates, metal/non-metal bonds might be described as ‘‘ approximately half covalent and half ionic”? (Ahrens, 1953). Thus elements which tend to form metal/non-metal compounds which are predominantly covalent should tend to be chalcophilic, while those which form metal/non-metal compounds with ionic characteristics should tend to be lithophilic. 156 JOHN F. LOVERING. TABLE V. Ionization Potentials and Ionic Radii for Some 1+, 2+, 3+ and 4+ Cations. (Data from Ahrens, 1952, 1953, or Calculated from his Data). a. Univalent Cations. Lit Tit Zn+ | Agt | Cut Aut I (volts) ie sis 5-4 6-1 ~6 7-57 icy) 9-22 Radius (A) .. ae 0-68 1-47 >0-74 1-26 0-96 1-37 b. Medium-sized Divalent cations (0-6—0-85A). Tizt Mg?t+ Mn?2+ Ge?+ Fe?t+ Co2+ I (volts) 5 se 13-6 15-03 15-64 15-93 16-24 17-4 Radius (A)... oir >0-76 0-66 0-80 0-73 0-74 0-73 b. (continued) Zn2+ Cr2+ Ni?+ Pd?+ Cu2t+ Ga*+ I (volts) a as 18-0 ~18 18-3 19-9 20-28 20-51 Radius (A) .. oo 0-74 ~0:-73 0-69 0-80 0:72 0-71 c. Large Divalent Cations (0-85-1-35 A). Ba2+ Ca2+ V2+ Sn2+ Pb2+ T (volts) at oh 10-0 11-9 14-2 14:6 15-05 Radius (A) .. ae 1-34 0-99 0-88 0-93 1-20 d. Trivalent Cations. Se3+ Vest | Al8+ | Fe3+ | Ga3+ Cr3+ T (volts) ae a 24-75 ~26°5 28-4 30-6 30-7 ~32-1 Radius (A)... os 0-81 0-74 0-51 0-64 0-62 0-63 e. Tetravalent Cations. Pibt® Sn4t+ aac | Sit Gett Vee TI (volts) ns a 39 40-70 43-24 45-1 45-7 ~48°5 Radius (A) .. bC 0-84 0-71 0-68 0-42 0-53 0-63 THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. 157 In an attempt to predict the type of metal/non-metal compounds which the various elements would form, Ahrens (1953) has abandoned the classical covalent approach to bond formation and with it the use of Pauling’s (1948) electro- negativities to indicate bond type in favour of an “‘ionic approach to bond formation’. From Ahrens’ point of view, the formation of a bond passes through three main stages ; first, that of initiation of the reaction ; second, an intermediate or transitory ‘‘ free-ion’’ stage; and third, equilibrium. The important stage, as far as the geochemical behaviour is concerned, is that in which virtually free cations and anions are formed. In this stage anion affinity has been defined as the power of a free cation to attract anions. Ahrens used ionization potentials (i.e. last-stage ionization potentials for M”-0+—+M"+ +e) to indicate anion affinity. He pointed out that anion affinity is related to such properties as polarizing power, ionic potential and field strength which have been defined by other authors, but that none of these take into consideration variable screening of the nucleus by ions of different electronic configuration. In the final stage, coulombic attraction between cation and anion draws them together to give an equilibrium product. If the anion affinity (7.e. ionization potential, J) is small, the metal/non-metal bond will be largely ionic; if anion affinity is large, the bond will be largely covalent. The degree of covalent character may be regarded as the degree with which the anion has its negative charged distribution drawn towards the cation (7.e. the degree of polarizability of the anion in the field of the cation). Ahrens has discussed the geochemical distribution of elements between sulphide and oxide (rather than silicate) phases. The S?- anion is much more easily polarized than the O?- cation, so that metal-sulphur bonds have a greater covalent character than metal-oxygen bonds. Thus for ions of the same valence and similar size, those with the highest ionization potentials should show the greatest tendency to form covalent bonds with sulphur and thus to concentrate in the sulphide phase (i.e. be chalcophilic). The sulphide phase in the pallasites is FeS and the highest stable oxidation state in which the elements under discussion can occur in FeS has been shown before to be +2. Thus we will restrict this discussion to the behaviour of those elements whose divalent cations are of similar size to the Fe?*+ ion and can replace it in the FeS structure. Ahrens (1953) has previously stated that an I value greater than about 15-5 v. is required before the element tends to preferentially enter the sulphide phase. In the meteorites the lithophilic versus chalcophilic character of a cation of similar size and valence to that of Fe?+ will depend on its I value relative to that of Fe?+ (7.e. 16-2 v.). Elements whose divalent cations have I values considerably greater than 16-2 v. should be chacophilic in behaviour, while those with I values considerably lower than 16-2 v. should be lithophilic. It would seem to be a fair assumption that cations whose I values were within +0-5 v. of the I value of Fe?+ might be either chalcophilic or siderophilic. Increasing I value relative to Fe?+ should correspond to increasing chaleophilic character for the elements and decreasing I value should correspond to increasing lithophilic character. From Figure 2 it would appear that in general this relationship does hold, at least insofar as Cu, Ni, Cr, Co, Mn and Mg are concerned, but Ti seems to be less lithophilic than its I value would suggest. Precise values of C,, which is the measure of the lithophilic-chacophilic behaviour of an element, for Ga and Ge are not available, but their I values would suggest that Ga should be relatively strongly chalcophilic, while Ge could be either chaleophilic or lithophilic. The behaviour of V and Pb is complicated by the fact that their divalent cations are significantly larger than Fe*+, but just taking into account their I values, then both V and Pb should be lithophilic. The available data would indicate that V is indeed strongly lithophilic, while Pb is almost certainly chalcophilic. 158 JOHN F. LOVERING. Chalcophilic-Siderophilic Behaviour. Ahrens (1953) has stated that for all valence groups, extremely high I values for a cation would indicate that the outer valence electrons are tightly held. lO es ~ O-. ie) Cu S (26) c ; £3 0 Ore =, £ .c a fe) aS) 1e) 6 OF ----© - - j-- ~--- rid nie eek NAY YX [s) U tre | > c oe te 8 (= w| 85 a/0 “Es(6 > es Of SIS =0 ce i" a ng {e) O = IS 16 7 ts} ie) 20 2l lonization Potential G) Text-fig. 2.—Lithophilic-chalcophilic behaviour of certain divalent cations of comparable size (0-6—0-85 A.) as a function of their ioniza- tion potentials. Notes : Some off-seale cations of comparable size are Ti (C,: O-012, I: 13-6 v), Ga (C,>0-03, 1: 20-51 v) and Ge (C,>0-06,1I: 15-93 v) while V (C,: 0-097, I: 14:2v) and Pb (C,>0-2, I: 15-05v) are significantly larger cations also off-scale. As a result, these elements are reluctant to enter into chemical combination and elements with very high I values should tend to remain native. However, an inspection of the data in table V will show that this is only partly true. Thus Ahrens’ statement probably represents an over-emphasis of one parameter. With regard to the chalcophilic-siderophilic behaviour of certain elements in THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. 159 meteorites, let us again refer to the ionization potentials of their divalent cations relative to that of Fe?+. As has been assumed in the lithophilic-chalcophilic discussion, cations whose I values are within +-0-5 v. of Fe?+ may be either chalco- philic or siderophilic relative to Fe. Then cations whose I values are greater than about 16-7 v. should be siderophilic, with greater siderophilic tendencies as the I value increases. Similarly, cations whose I values are increasingly less than about 15-7 v. should be increasingly chalcophilic. (oye) io oe U re Ni s © (e) See rw J8 oO Ge =6 Ae O /§E 2 |S /% El Fo 2 Sie arr’ 2 (4 BOR ra ----------------- it we S 3 oe ae (4 8 o 6 CrCOO2) 6 17 18 19 20 2l lonization Potential GQ) Text-fig. 3.—Chalcophilic-siderophilic behaviour of certain divalent cations of comparable size (0-6—0-85 A.) as a function of their ionization potentials. Notes: Ti (C,: <0-4, I: 13-6 v) is an off-scale cation of comparable size while V (C,: <0-:07,1: 14-2) and Pb (C,: 0-018, 1: 15-05 v) are significantly larger cations also off-scale. From Figure 3 it would appear that the elements Ga, Ni, Co, Ge, Mn, and perhaps also Mg and Ti, do follow the predicted trend, although Cu and Cr are apparently well off the curve. The significantly larger size of the divalent V and Pb cations might be expected to introduce complications, but their I values would suggest they should be non-siderophilic, as has been observed to be the case (Table I). All in all, ionization potentials are of considerable use in predicting the geo- chemical behaviour of elements, provided that their oxidation states are known. 160 JOHN F. LOVERING. Part II. BEHAVIOUR OF ELEMENTS DURING THE CRYSTALLIZATION OF IRON METEORITES. In a previous work (Lovering, 1957a) it has been shown that the observed nickel contents of iron meteorites are consistent with their having differentiated by a process akin to fractional crystallization from an originally homogenous melt of about 11% nickel. For nickel the distribution coefficient, k, given by the ratio nickel concentration in solid phase nickel concentration in remaining melt is about 0-5, so that the first formed crystals of iron-nickel alloy have the lowest nickel contents. As crystallization proceeds, the nickel content of the solid phase gradually increases. From analytical data recorded by Goldberg eé al. (1951) and Lovering et al. (1957), it would seem that certain other siderophilic elements (e.g. Co, Cu, Pd, Au) behave in a similar manner to nickel and have distribution coefficients <1. On the other hand, analytical data for Ga and Ge (Lovering et al., 1957) would indicate that k values for these elements are considerably greater than 1, so that the first formed solid phase has a very high Ga and Ge concentration while the last solid phase to crystallize is very much impoverished in both elements. There is also some evidence that unlike Co, Cu, Pd and Au, both Ga and Ge do not vary smoothly when compared to the nickel content of the alloy but seem to concentrate in three or even four distinct levels. Some possible reasons for this unusual behaviour will form the subject of another work which is at present in preparation. The purpose of this discussion is to attempt to explain the tendency of certain elements to concentrate in the solid phase relative to the liquid phase (i.e. elements with k>1), and other elements to concentrate in the liquid phase relative to the solid phase (7.e. k <1) during the crystallization of the metal iron melt. Solid Solutions in Metals. According to Darken and Gurry (1953), the following factors control the extent of primary solid solution in metals : Size factor: primary solid solution is seriously hindered whenever the dis- parity in atomic radii exceeds 15 per cent. In this discussion we are dealing with fractionation of elements between the metal melt and the face-centred cubic (y-phase) iron-nickel solid which crystallizes first. Thus the 12-fold co-ordination radii of the elements should be used. Hlectronegativities : metallic elements with electronegativities within -+0-4 electronegativity units of the substituted element have maximum solid solubility (i.e. >5 atoms per cent.) in that element. Electronegativities may also be used to predict the behaviour of a trace- element during the crystallization of a melt. For instance, Ringwood (1955) studied the distribution of elements during the crystallization of silicate magmas. He pointed out the general weakening effect of increased covalent bonding in a compound and used electronegativities (i.e. the power of an atom to attract electrons) to determine the extent of covalent relative to ionic bonding in a compound. The greater the difference in electronegativity of two atoms which are bonded together, the more ionic (7.e. stronger) the bond will become. Ring- wood was able to propose that whenever diadochy in a crystal is possible between two elements possessing appreciably different electronegativities, the element with the lower electronegativity will be preferentially incorporated because it forms a stronger and more ionic bond than the other. A difference of 0-1 or THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. 161 more in electronegativities is necessary before this rule has a significant effect on diadochic substitutions. Given Pauling’s (1948) concept of metallic bonds as essentially resonating covalent bonds and Ahrens’ (1953) ionic approach to covalent bond formation described previously, then it is felt that the application of Ringwood’s dictum, concerning electronegativities of elements and their behaviour in the crystallization of silicate melts, to the crystallization of metallic melts has certain justification. Thus, considering the iron metal melt in the meteorite environment, elements with electronegativities less than that of Fe will be preferentially incorporated in the early crystallizing solid phases and should decrease in concentration in the solid phase as crystallization proceeds. Those elements whose electronegativities are greater than Fe will tend to remain in the melt and should gradually increase in concentration in the solid phase which separates as crystallization proceeds. TABLE VI. Metallic Valencies and 12-fold Co-ordination Radii (after Pauling, in Darken and Gurry, 1953) of Certain Elements and Their Electronegativities. 12-fold Co-ordi- Metallic Selected Value of Element. Metallic nation electro- Electronegativity Valence. Radius negativity | (Gordy and Thomas, (A) (X) 1956). Cr 6 1-267 2-24 1-4(2)* Fe 5-78 1-260 2-30 1-7(2) Co 6 1-252 2-37 U7 Ni 6 1-244 2-38 1-8 Cu 5-44 1-276 2-20 2-0(2) Ga 3-44 1-408 1-61 1-5 Ge 4 1-366 ovis 1-8 Pd 6 1-373 2-20 2-0 Au 5-44 1-439 2-00 2-3 * Figure in brackets is valence state to which the selected electro- negativity value refers. We may look upon those elements with smaller electronegativities as forming metallic bonds (or resonating covalent bonds, in the sense of Pauling) with Fe in which the ‘ionic character” is greater than those with higher electro- negativities. These bonds will be stronger and consequently will be more stable in the relatively high temperature environment in which the first crystals form. Thus a knowledge of the metallic radius and the electronegativity of an element (Table VI) relative to Fe should be sufficient to determine whether that element (1) has unlimited substitution of Fe, and (2) is concentrated in either the solid or liquid phase as crystallization proceeds. From the information plotted in Figure 4a, the following conclusions may be drawn : (i all metals plotted (except Au) should have maximum solubility in iron ; ) (ii) Cu, Pd and Au should be concentrated in late-forming solid phase ; (iii) Ga should be enriched in early-forming solid phase relative to the melt ; (iv) behaviour of Ni, Ge and Co cannot be predicted as electronegativities of these elements lie between +-0-1 electronegativity units of Fe. This would certainly explain the qualitative behaviour of Cu, Pd, Au and Ga, but it does not explain the behaviour of Ge. With regard to the behaviour of gallium, it is interesting to point out that Petit and Nachtrieb (1956) found that liquid gallium is more metallic in character 162 JOHN F. LOVERING. than the solid phase, suggesting that gallium should tend to concentrate in the solid phase crystallizing from a metal melt, as has been observed from the analytical data. Electronegativity 3-0 OAuCl) Electronegativity Metallic 8 LO 2 4 6 l2-fold co-ordinate radius CA) (b) Text-fig. 4.—The behaviour of certain elements in the metallic phase of iron meteorites as related to their metallic radii and (a) electronegativities (Gordy and Thomas, 1956), (b) metallic electro- negativities (this work). Notes: Elements increasing with nickel (open circles); elements decreasing with nickel and showing ‘‘ quantized”’ distribution (full circles). Elements with maximum (>5 atoms per cent.) substitution for Fe lie inside the large circle. Metallic Electronegativities. Gordy (1946) has derived an equation which expresses the electronegativity (x) of aneutral atom as a function of the number of electrons (n) in the incompletely filled (valence) shell and the single-bond covalent radius (r) of the atom: x=0-31 (a sip Qusnt aud Ae Lieut (1) 7 THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES. 163 Darken and Gurry (1953) have pointed out that more significant values for the electronegativities of Class I elements (the true metals) are given if Pauling’s metallic valences (n!) are used in place of the term n in Gordy’s equation (1). The electronegativity value so defined will be called here the metallic electro- negativity, and has been calculated for a number of elements (Table VI). If we now plot the metallic radii and metallic electronegativities of some elements (Figure 4b), the following conclusions may be drawn : (a) all metals plotted, except Au, Ge and Ga, should have maximum solubility in iron. (b) Au, Ge and Ga should be enriched in first-formed crystals. (c) behaviour of Ni, Co, Cu, Pd cannot predicted. The behaviour of elements Ga, Ge, outside the area of maximum solubility is explained on this basis. With regard to gold, Darken and Gurry (1953) have shown that the behaviour is best explained by using an electronegativity value based on the unit valence state. Using this new value, the tendency should be for gold to concentrate in the melt, as has been observed. SUMMARY. The geochemical behaviour of certain elements (Mg, Ti, V, Cr, Mn, Co, Ni, Cu, Ga, Ge, Pb) relative to their distributions between the silicate (olivine), sulphide (troilite) and metal phases of pallasitic stony-iron meteorites has been determined from new data. Oxidation potentials are used to indicate the most likely oxidation states of the elements in the various phases. Ionization potentials of the divalent cations are used to indicate their anion affinity relative to Fe?+ and consequently to explain their relative lithophilic-chalcophilic-siderophilic tendencies. The distribution of Ga, Ge, Co, Pd, Cu and Au in iron meteorites is discussed as a function of the behaviour of these elements during the crystallization of an iron-nickel melt forming the core of the parent meteorite body. Metallic electronegativities (x) for each of these elements, relative to Xye, are used to predict whether an element is concentrated in the solid or the liquid phase as crystallization of the melt proceeds. The metallic electronegativity of a metal is calculated from a modified version of Gordy’s (1946) equation in which x=0°-31 [(n1+1)/r]+0-50 where ni—Pauling’s metallic valence, and r—the 12-fold co-ordination radius for the element. REFERENCES Ahrens, L. H., 1952. ‘‘The Use of Ionization Potentials, Part I. Ionic Radii of the Elements.” Geochim. et Cosmochim. Acta, 2, 155-169. 1953. “‘The Use of Ionization Potentials, Part 2. Anion Affinity and Geo- chemistry.” Geochim. et Cosmochim. Acta, 3, 1-29. Darken, L. 8., and Gurry, R. W., 1953. ‘‘ Physical Chemistry of Metals.’ McGraw-Hill, New York, 535 pages. Goldberg, E., Uchiyama, A., and Brown, 1951. ‘‘ The Distribution of Nickel, Cobalt, Gallium, Palladium and Gold in Iron Meteorites. Geochim. et Cosmochim. Acta, 2, 1-25. Goldschmidt, V. M., 1954. ‘‘ Geochemistry” (edited A. Muir). Oxford University Press, London 730 pages. Gordy, W., 1946. ‘* A New Method of Determining Electronegativity from Other Atomic Properties.” Physical Review, 69, 604-607. Gordy, W., and Thomas, W. J. O., 1956. ‘“* Electronegativities of The Elements.” Jowrn. Chem. Phys., 24, 439-444. Latimer, W. M., 1938. ‘‘ The Oxidation states of the Elements and Their Potentials in Aqueous Solutions.”’ Prentice-Hall, Inc., New York, 352 pages. > 164 JOHN F. LOVERING. Lovering, J. F.,1957a. ‘‘ Differentiation in the Iron-nickel Core of a Parent Meteorite Body.” Geochim. et Cosmochim. Acta, 12, 238-252. 19576. ‘‘ Pressure and Temperatures Within a Typical Parent Meteorite Body.” Geochim. et Cosmochim. Acta, 12, 253-261. 1957c. ‘* A Model for the Mantle of the Primary Meteorite Body and the Origin of the Primary Stony Meteorites (in preparation). Lovering, J. F., Nichiporuk, W., Chodos, A., and Brown, H., 1957. ‘‘ The Distribution of Gallium, Germanium, Cobalt, Chromium and Copper in Iron and Stony-iron meteorites in Relation to Nickel Content and Structure.’’ Geochim. et Cosmochim. Acta, 11, 263-278. Patterson, C. C., Tilton, G., and Inghram, M., 1955. ‘‘ Age of the Earth.” Science, 121, 69-75. Pauling, L., 1948. ‘‘ The Nature of the Chemical Bond.’ Cornell University Press, New York, 450 pages. Perry, 8. H., 1944. ‘‘ The Metallography of Meteoric Iron.” U.S. Nat. Mus., Bull.,184, 206 pages Petit, J., and Nachtrieb, N. H., 1956. ‘‘ Self-diffusion in Liquid Gallium.” Journ. Chem. Phys., 24, 1027-1028. Rankama, K., and Sahama, Th, G., 1950. ‘‘ Geochemistry.’” University of Chicago Press, Chicago, 912 pages. Ringwood, A. E., 1955. ‘The Principles Governing Trace-Element Distribution During Magmatic Crystallization, Part. I: The Influence of Electro- negativity.”’ Geochim. et Cosmochim. Acta, 7, 189-202. 1956. ‘‘ Melting Relationships of Ni-Mg Olivines and Some Geochemical Implications.” Geochim. et Cosmochim. Acta, 10, 297-303. AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. SEAMER AND ARUNDEL STS., GLEBE, SYDNEY he an 4 - > 'e a : ‘= 7 + a : = ' i a ed ; : - 5 - a yi" : : at 1 re | a 1 ‘ 07 ae A ca a . aye ary neo An ue eet ys, A. it an i : . NOTICE, _ THE Bae Soorzry 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, it assumed its present title, and was incorporated by Act of the Parliament of New South Wales in 1881. TO AUTHORS, Particulars regarding the preparation of manuscripts of papers for publication in the Society’s Journal are to be found in the “ Guide to Authors”’, which is obtainable on appli- cation to the Honorary Secretaries of the Society. . The previous volumes and depen pots of the Journal and Proceedings may be obtained at the Society’s Rooms. ee The Library and Reading Room of the Society at Science House, Gloucester and Hssex Streets, Sydney, is eaieuis for the use of members on week-days, 10 a.m.to 12 noon and 2 p.m. S60. 4 ‘p.m. : = CONTENTS VOLUME XQI Part IIl ART. XI.—BOUNDARY STRESSES IN AN INFINITE HUB OF SPECIAL SHAPE. Alex. Reichel ae tee oh oe oH te : ‘ART. XII.—BASIC AND ULTRABASIC RockS NEAR HAPPY JACKS AND Tumut PoND IN THE SNOwy MOUNTAINS OF New SoutH WALES. Germaine A. Joplin a: ae ae = ie é Art, XITI.—On A FoRMULA OF THE CONVOLUTION TYPE RELATED TO HANKEL TRANSFORMS. James L. Griffith a ae 5 313 ArT, XTV.—THE GEOCHEMICAL BEHAVIOUR OF ELEMENTS IN METEORITES; J. EF. Lovering as as Hi ay, SH at : Page 109 120 142 149 THE AUTHORS OF PAPERS ARE ALONE RESPONSIBLE FOR THE STATEMENTS MADE AND THE OPINIONS EXPRESSED THEREIN. AUSTRALASIAN MEDICAL PUBLISHING CO. LTD, SEAMER AND ARUNDEL STS,, GLEBE, SYDNEY ; | ire | J { HU ~ hf ft a, —2e 4 Pee , 6 Y DN EY | ay | JOURNAL AND PROCEEDINGS | | OF THE ROYAL SOCIETY OF NEW SOUTH WALES 1957 Edited by the Honorary Editorial Secretary PUBLISHED BY THE SOCIETY SCIENCE HOUSE, GLOUCESTER AND ESSEX STREETS, SYDNBY ISSUED APRIL 23, 1958 Registered at the General Post Office, Sydney, for transmission by post as a periodical. Royal Society of New Snuth Wales OFFICERS FOR 1957-1958 Patrons: His EXcELLENCY THE GOVERNOR-GENERAL OF THE CoMMONWEALTH OF AUSTRALIA FIELD-MarsHAL SiR WILLIAM SLIM,-G.0.3., G.C.M.G., G.C.V.0., G.B.E., D.S.0., M.C. His EXcELLENOY THE Govmiubs: or New Soutx WALEs, LikUTENANT-GENERAL SiR ERIC W. WOODWARD, &.o.M.G., C.B., 0.B.E., D.S.0. President : F. N. HANLON, B.sc. Vice-Presidents ; 3 Rev. T. N. BURKE-GAFFNEY, s.s. F. D. McCARTHY, pDip.anthr. H. A. J. DONEGAN, m.sc. é C. J. MAGEE, p.sc.4gr. (Syd.), M.sc. (Wis.). Hon. Secretaries : J. L. GRIFFITH, B.a., m.sc. ee | IDA A. BROWNE, pD.sc. — Hon. Treasurer : : EF. W. BOOKER, Ph.p. m.sc. Members of Council: G. BOSSON, m.sc. (Lond.). PHYLLIS M. ROUNTREE, p.se. (Melb. )> G. W. K. CAVILL, m.sc. (Syd.), Ph.D. Dip.Bact. (Lond.). (Iiverpool). G. TAYLOR, D.se. B.E. (min.), (Syd.), J. A. DULHUNTY, -p.sc. B.A. (Cantab.), F.A.A. : A. F. A. HARPER, M.Sc. H. F. WHITWORTH, msc. D. P. MELLOR, pb.se. | H. W. WOOD, msc. — W. H. G. POGGENDORFF, B.Sc.Agr. JOURNAL AND PROCEEDINGS OF THE ROYAL SOCIETY OF NEW SOUTH WALES L957 Edited by the Honorary Editorial Secretary PUBIASHED BY THE SOCIETY, SCIENCE HOUSE, GLOUCESTER AND ESSEX STREETS SYDNEY mr MP, ZO8L | en ARY JUN = 3 1958 | wienslTY CLARKE MEMORIAL LECTURE* FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF NEW SOUTH WALES. By ALAN H. VOISEY, D.Sc. Department of Geology, University of New England, Armidale, N.S.W. With six Tables. ABSTRACT. Work done on the sedimentary formations of N.S.W. since 1947 is discussed and the rocks are arranged according to the Australian Code of Stratigraphical Nomenclature. A bibliography of publications on N.S.W. stratigraphy since the publication of T. W. E. David’s *‘ Geology of the Commonwealth of Australia’? in 1950 is given, and the contri- butions made are organized into tables showing the recognized formations and groups defined up till the end of 1956. CONTENTS. Page Introduction .. Be Ste sys ats sie xe ae its 165 History of Stratigraphical Investigations .. We re ae a 166 The Sedimentary Formations ae Be 3 5e 5 xc 168 Ordovician 8 Ae ae we ns ae ue a 168 Silurian .. “fs ar ts ius a's sue 3 as 170 Devonian .. is ~ = ss a v3 oe ote 173 Carboniferous ays rs “i ss je = bes a) Lis Permian .. age ws os ote 3 ae sis ss 178 Triassic .. is a a a we a ae He 181 Jurassic .. is ae a ae aa ee as ~~ 181 Cretaceous. . Sh Sd ae ae ae sé we is 181 Tertiary .. te 510 ose op o6 ae 5c ae 181 Pleistocene e ae aye aie oie a as ahs 183 The Future ae sie Ne eo aS at ts ae <3 183 Bibliography .. oe bs SIG Sc ar is iis a 184 INTRODUCTION. I feel that I can pay no better tribute to the Reverend W. B. Clarke, in whose memory I am delivering this lecture tonight, than by discussing ‘ the sedimentary formations of New South Wales”. For nearly forty years this great man, aptly called ‘the Father of Australian Geology ”’, laboured upon them single-handed with little or no equipment save those articles which, I maintain, are still the most important which a geologist can possess, namely, a pair of strong boots, a hammer and a haversack. For longer journeys—and he made many of them—he had to rely upon the horse. I propose tonight to deal very briefly with the progress of research since Clarke started his work, then to discuss the advances we have made in the last decade, and finally, to suggest what progress we might make in the future. * Delivered to the Royal Society of New South Wales, July 30, 1957. 166 ALAN H. VOISEY. HISTORY OF STRATIGRAPHICAL INVESTIGATIONS. It is convenient to consider the history of stratigraphical investigations in this State in three main periods : The first might be said to extend from 1839 to 1878, as it was during this time that the Rev. W. B. Clarke carried out the work which he discussed in his book ‘‘ Remarks on Sedimentary Formations of New South Wales”, 4th Ed., 1878. The second, from 1879 to 1946, was dominated by the work and influence of Professor Sir T. W. E. David and later by Dr. W. R. Browne. Advances made were included in “ The Geology of the Commonwealth of Australia ’’, 1950. The additions to our knowledge which took place during the third period, from 1947 to 1957, will be my main concern tonight. It is quite clear that Clarke paved the way for later work by his careful determinations of the order of superposition of the strata, which he saw as he travelled through the State. He was essentially a field geologist, who placed more value upon his own observations than upon the views of the paleontologists such as McCoy, to whom he submitted the fossils which he collected for identification. In spite of under- standable differences of opinion, he received much aid and encouragement from some of his famous contemporaries, namely, Sir Roderick Murchison, Professor Adam Sedgwick, Professor L. G. de Koninck, Dr. O. Feistmantel, W. Lonsdale and J. W. Salter. He brought together the records of the early explorers, P. E. de Strzelecki, T. L. Mitchell and L. Leichhardt, and visitors in the persons of J. B. Dana and J. B. Jukes. Following the identification of many of the 4,000 specimens he sent to the Woodwardian Museum, Cambridge, he was able to effect broad correlations between the sedimentary formations of N.S.W. and overseas sequences. During the second period rapid building took place on Clarke’s solid founda- tions. In the bibliographies of ‘‘ The Geology of the Commonwealth ” some fifty persons are listed as contributing to the geology of New South Wales. Most of the early work was done by T. W. E. David, W. G. Woolnough and W. N. Benson, through the University ; and by C. 8. Wilkinson, E. F. Pittman, J. E. Carne, J. B. Jaquet, R. Etheridge, Junr., and W. 8. Dun, through the New South Wales Geological Survey. They were later joined by L. A. Cotton, W. R. Browne, A. B. Walkom, L. L. Waterhouse, G. D. Osborne and I. A. Brown at the University ; E. C. Andrews, L. F. Harper, L. J. Jones, KE. J. Kenny, A. C. Lloyd, H. G. Raggatt and C. J. Mulholland in the Survey ; and C. A. Sussmilch at the Technical College. Some contributions were also included in the book from those who might be regarded as belonging to the third period: G. A. Joplin, K. Sherrard, F. Booker, S. W. Carey, J. A. Dulhunty, J. Crockford, F. Hanlon, and myself. ‘““ The Geology of the Commonwealth ” brought together the stratigraphical work done in Australia; the sedimentary formations were organized into “series? and “stages ’’ and intra-continental correlations were made; _ fossil zones were recognized and more detailed correlations with overseas sequences were suggested. The third period, commencing in 1947, the last year from which W. R. Browne was able to collect material for the book, is characterized by the attempt to introduce an Australian Code of Stratigraphical Nomenclature in order to control the subdivision and naming of the rocks. Because of the increasing number of sequences being described there arose the need for separate ‘‘ rock ” terms as distinct from the time-rock terms “ series ’’ and “‘ stage ’”’, which were coming more and more into use in a dual sense. FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. 167 The move initiated by Glaessner, Raggatt, Teichert and Thomas in 1948 and discussed at a number of meetings (see Raggatt, 1950, 1953) led to the acceptance of the code, the latest statement of which was published in the Australian Journal of Science in February, 1956 (Raggatt, 1956). Rock sequences are now divided into “ groups ”’, ‘“‘ formations ’’ and ‘‘ members ”’. The terms ‘‘ series”? and ‘“ stage” are applied only in a time-rock sense corresponding with the time-terms ‘‘ epoch ” and “‘ age’, and should preferably be of world-wide application. They may have intra-continental validity, where correlation on a wider basis is difficult or impracticable. There is as yet no universal acceptance of time or time-rock terms of world- wide application. W. R. Browne (1949) pointed out that in Australia the major subdivisions on the whole have been standardized on the European scale and that it is undesirable to change them. Nevertheless, it has been the custom in New South Wales to use a number of our own time and time-rock terms—the most common being the division of the Permian into Lower Marine, Lower Coal, Upper Marine and Upper Coal, and of the Carboniferous into Burindi (Lower and Upper) and Kuttung (Lower and Upper). Other series and stage names as originally given in relation to certain sequences, such as those in the Cumberland Basin, Yass and Tamworth districts, have not been widely used elsewhere, largely because of doubts about correlation. The term Lambian has been used to imply a particular facies, but has also assumed a time-rock significance. There is much to be said for the adoption of local time and time-rock terms, if only to cover the period of uncertainty about inter-continental correlations. The question as to whether they should be State-wide or Australia-wide is one which can really only be decided by usage. In New South Wales we seem to be making use of the Victorian Ordovician stage names of Bolindian, Eastonian, Gisbornian, and so on. Queensland names of Bunya and Neranleigh-Fernvale for some unfossiliferous Paleozoic (?) beds common to both States are frequently used. The practice which the code insists must be discontinued is the employment of the time-rock terms ‘ series ”’ and ‘‘ stage’ for rock sequences, as was done prior to its acceptance. Illustrative of what would now be regarded as their misuse is my own work on the North Coast. I introduced the names Boonanghi Series and Kullatine Series for strata supposedly of Burindi and Kuttung age, because I was not sure of their exact limits in time. Had I been doing the work since the code was introduced, I would have called them the Boonanghi Beds and Kullatine Beds until I had defined a number of formations, after which they would have been organized into the Boonanghi and Kullatine groups (Voisey, 1934). While I do not now advocate any changes in our system of nomenclature, I desire to express the view that we might be better advised to continue to use our own time and time-rock terms until we are satisfied that the paleontologists have established close correlations with overseas standard series and stages. It should be in order to speak of the Dalwood and Macleay groups of sedimentary rock as being of Lower Marine age. This might be preferable to using the Russian terms, Artinskian and Sakmarian, at the present time. The division and description of rock sequences using the code has become the prime task of stratigraphers during the last decade. The Geological Survey of New South Wales, led by Dr. F. W. Booker, has paid particular attention to the Coal-measures during this period, F. Hanlon (1947-48) being concerned with the North-west Coal-field, E. O. Rayner (1949) with the Western Coal-field, and F. Hanlon (1956) and C. E. McElroy (1957) with the Southern Coal-field. 168 ALAN H. VOISEY. Workers outside the survey have been relatively few, but N. C. Stevens (1948-1956), G. H. Packham (1953, 1954), R. L. Stanton (1955), J. Phillips (1955) and G. F. Joklik (1950) have described Lower and Middle Paleozoic formations in the Central-western areas of the State. G. D. Osborne (1950) gave a comprehensive account of the Carboniferous rocks, and F. C. Loughlan (1954) subdivided the Permian strata of the Gloucester Trough. G. D. Osborne (1948), J. F. Lovering (1953, 1954) and K. A. W. Crook (1956) have discussed the Triassic sequences. Much progress has been made in the study of the paleontology of the formations by I. Crespin (1955) (Foraminifera), D. Hill (1954a, 1957) (corals), K. Sherrard (1949, 1951, 1953) (graptolites), J. Crockford (1947, 1948, 1951) (Bryozoa), K. Campbell (1955, 1956, 1957) (brachiopods), H. O. Fletcher (1950) (molluses and _ trilobites), C. Teichert and B. F. Glenister (1952, 1953) (cephalopods), E. F. Riek (1954a, 19546) (insects) and R. T. Wade (1953) (fishes). I shall now proceed to a discussion of the recent stratigraphical contributions and to show by means of tables the correlations, both inter- and intra-continental, which have been made. THE SEDIMENTARY FORMATIONS. Pre-Cambrian. Pre-Cambrian beds outcrop in the Barrier Ranges. They are not known to occur in the eastern portion of New South Wales, although big thicknesses of unfossiliferous sediments, which may be older than Ordovician, are present. Ordovician. Black banded slates, siltstones, cherts and calcareous deposits in association with tuffs, breccias, andesitic conglomerates and andesite lavas have been found to contain Ordovician fossils. K.M. Sherrard (1953, p. 73) listed a number of graptolites, showing that representatives of the English Arenig, Llandeilo and Caradoc series are present. She herself mapped and described Upper Ordovician sediments from the Nanima-Bedulluck District but did not name any formations (Sherrard, 1951). N. C. Stevens (1952-1956) mapped Ordovician rocks in the central-west and showed that some limestones, formerly considered to be of Silurian age, contain a fauna which includes Bryozoa, stromatoporoids, Brachiopoda, Mollusca and corals, as well as graptolites. I. A. Brown (1952) deduced an Ordovician age from the brachiopods, and D. Hill (1955) recognized the coral fauna as being high in the Ordovician. Upper Ordovician graptolites were identified by K. Sherrard. Stevens, in addition to naming the formations as shown in Table A, pointed out that some of the lavas were characterized by pillow-structure and albitization, which suggest submarine origin, and that overlying shallow-water limestones may have developed on a ridge of volcanic material, associated perhaps with a rising, median geanticline. Greywackes were laid down probably in deep water in a region of more rapid subsidence east of the limestones. From the Wiseman’s Creek-Burraga area Stanton (1955) described under the heading of Triangle Group, a thickness of approximately 10,000 feet of ‘‘ low grade metamorphic products of predominant shales, greywackes, isolated chert lenses and very minor tuffaceous bands”. He did not name any formations. The Rockley Voleanics, overlying the Triangle Group, consist almost entirely of regionally metamorphosed andesitic pyroclastics, but with occasional flows or sills, and reach a thickness of approximately 5,000 feet near Rockley. Vallance (1953a, p. 96), in dealing with the metamorphism of sedimentary rocks in the Wantabadgery-Adelong-Tumbarumba District, noted that no successful attempt had been made to subdivide the sediments, probably Upper 169 FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. “uRlOpRUlaly, “UBIP[Eyoour'yT £ ou0jspurg 4 auojspuRg “‘uetuosIpuog ureyuNoyy Wovpq UIeJUNOP Yop. “UvISIUEly ‘uvtuoymoyg | —— % é Sa fs pee “URIUIVUIOTSVO ‘uviuoade x “WRIUTTAURTT “URTTIMIIeG, “UOT]RULIO, “U0]} VUIOT “weTTOpUryT elrelInyy ueulyywd ‘ayIsopuy oOB1VD ‘opsopuy oFIeD ‘ayISopUy TTB “uBIUIOgst) | SO ‘dnt C[B UCN, | —— 9S —— S$ —— | ——-— ——_ ——— oe *9U0JSOUI'T, SoABQ WOPJoNO *soU0}SOUIN'T “URIUO SEAL ‘aeyg woyOy ‘greys wopy Yo s,uesay *souO}SOUL'T, ‘uvloopriey) —t— i — i pue aurpoumoury) uoyleg, pure ‘qiegq ueMog Yoo o81"9 “UBIpUlog ‘sormRoJOA AdPPOOY é 60 é ‘== ‘yNy Ssuoynsuy “uel sysy “UOTJVULIO “MOTYVULIO TH 8. Mpoerey quel “Sava ‘SHOVES senna ‘aq users ren suo suet Nvaadoung NVIMOLOLA “NVAGANVaOY ‘VuddaNVO ‘vovuUNng “MUVd NVMOG *ANIGOWONVQ ‘SHAV) NOCAAITO -HaGUD S,NVWASIM “NVIOIAOGUO ‘Vy a1aVL 170 ALAN H. VOISEY. Ordovician in age. He considered that the assemblage of shales and sub- greywackes appeared to be fairly typical of what one might expect of sediments deposited near the axial region of a miogeosyncline. . In the Australian Capital Territory, according to Opik (1954, p. 135), the Black Mountain Sandstone (Pittman, 1911), at least 1,500 feet thick, is older than Middle Ordovician. The overlying Pittman Formation is a rhythmic sequence 700 feet thick of sandstones, micaceous sandy shales, mudstones, black argillaceous shales and radiolarites containing graptolites, conodonts, rare brachiopods and sponges. The succeeding Acton Shale is 200 feet thick. J. Phillips (1955), from the adjacent area of Queanbeyan in New South Wales, defined the Muriarra Formation and correlated it with the Pittman Formation. A number of reports by officers of the N.S.W. Geological Survey, notably L. R. Hall and C. L. Adamson, refer to slates, phyllites, quartzites, schists and cherty shales in the southern part of the State. Fairbridge (1953, P. III, 13-14), from the vicinity of Kiandra and Adaminaby, described a eugeosynclinal sequence of sediments possibly some 40,000 feet in thickness. Geologists of the Bureau of Mineral Resources and the Snowy Mountains Hydro-Electric Authority have carried out extensive investigations of the geology of the Snowy Mountains area, but little information has yet been published. As noted in many publications unfossiliferous phyllitic rocks, apparently of great thickness, outcrop on both the South and North Coasts of New South Wales, continuing into Queensland. In 1934 I gave the name Nambucca Series to beds occurring typically at Nambucca Heads and correlated them with the Bunya Phyllites of Queensland (Voisey, 1934, p. 335). They will, in future, be referred to as the Nambucca Beds in accordance with the code. The broad general picture of Ordovician times resulting from a consideration of the beds described is that of a depositional area consisting of two main depres- sions in the ocean floor, that to the west being a miogeosyncline (Kay, 1950) and that to the east a deep eugeosyncline. Between the two lay a region where ridges and troughs gave rise to mixed shelly and graptolite facies, greywackes and limestones occurring in close proximity to one another. Silurian. As a result of his ardent collecting Clarke established the presence of Silurian rocks in N.S.W., and a list of fossils of that age identified by de Koninck is quoted by Clarke (1878, p. 12 and Appendix XIV). I. A. Brown and K. M. Sherrard (1951) correlated the beds of the Yass- Bowning area with the Wenlock and Lower Ludlow of England on the basis of the graptolite identifications. In 1954 I. A. Browne described the area of deposition as ‘‘ a broad, generally shallow sea-way, probably dotted with islands and archipelagoes, with which were associated coral reefs and beach deposits ”’. She noted that the greater part, if not the whole of the Silurian sequence, was developed in the neighbourhood of Yass and estimated the total thickness of Silurian beds as 8,300 feet. G. A. Joplin (1952), in a useful summary of the Wellington-Molong-Orange- Canowindra region, arranged previous work in accordance with the code of stratigraphical nomenclature, dividing the Silurian sequence into : (i) The Manildra Formation consisting of cherts, shales, tuffs and limestone with porphyries. (ii) The Nanima Formation of limestones, andesite flows, pyroclastics and intrusives. (iii) The Gamboola Formation of limestones and shales. FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. 171 Stevens and Packham (1952), from Four Mile Creek, south-west of Orange, defined the Panuara Formation with the Bridge Creek Limestone Member at the base. From the graptolite assemblage, which included Monograptus gregarius, M. exiguus and M. dubius, they concluded that the formation com- prised the equivalents of the Lower Llandovery, Upper Llandovery, Wenlock and Lower Ludlow Series of Great Britain. They pointed out that the Bridge Creek Limestone was the first in Australia for which a basal Silurian age had been proved. They suggested that it might extend downwards into the Ordovician. The overlying unfossiliferous Wallace Shale may be either Upper Silurian or Lower Devonian. The same authors described the occurrence of the Panuara Formation in the Spring and Quarry Creeks area, noting that Joplin (1952) had included it in the Gamboola Formation, regarded as Lower Silurian (Packham and Stevens, 1954). They called the fossiliferous limestone at the base the Quarry Creek Limestone Member. From the Australian Capital Territory A. A. Opik defined the formations of a Silurian sequence as shown in Table B. He noted that it was from the Yarralumla Formation that Clarke (1878) collected a number of the fossils which were described by de Koninck (1876-1877). Phillips (1955) described over 1,000 feet of similar beds from the Queanbeyan area. As to structural relations Opik (1954, p. 138) recognized the unconformity between the Camp Hill Sandstone and the Ordovician Black Mountain Sandstone, and Phillips (1955, p. 120) recorded the former’s disconformable relations with the Upper Ordovician Acton Shale. Opik regarded the Yarralumla Formation as being folded before the Mount Painter Porphyry was intruded in Lower Ludlow time. The Ainslie Voleanics, believed to be Lower Devonian, are unconformably resting on the eroded surfaces of Silurian rocks. Sherrard (1951, p. 69) described sandstones, quartzites, limestones and mudstones in the Nanima-Bedullick District, correlating the fossil zones with the English Ludlow and Wenlock. Formation names were not given. The Wiseman’s Creek-Burraga rocks, probably all of Silurian age, were divided by Stanton (1955) into: (i) Burraga Group (4,500 ft.) of greywackes, shales and andesitic tuffs. (ii) Kildrummie Group (6,000 ft.) of limestones and shales. (iii) Campbell’s Group of Shales, greywackes and conglomerates. No formation names have yet been given. The Silurian sequence at Cobar, previously mapped by E. C. Andrews, was divided by G. F. Joklik (1950) as shown in Table B. He described the Cobar Group as comprising shore-line deposits showing frequent change of facies and with contemporaneous vulcanism. Vuleanicity continued into the Upper Silurian, the products being associated with radiolarian cherts and limestones. In north-eastern New South Wales many observations have been made upon the Woolomin and Fitzroy beds, which are possibly Silurian. A. Spry (1953, 1955) mentioned polymictic breccias, greywackes, sub-greywackes, quartzites, jaspers, biotite hornfelses, calc-silicate hornfelses and basic lavas as belonging to the Woolomin Group. J. W. Whiting (1950) recorded Silurian fossils from an isolated outcrop of limestone near Jackadgery. This discovery suggests that the jaspers and quartzites of Woolomin type in the locality are also of Silurian age but field relationships do not appear to be clear enough to establish the matter beyond doubt. ALAN H. VOISEY. 172 *AIOAOPULT'T “OOTTO M “MOTPU'T IOMOT “MOTPL'T roddy “BaINAS NVadOUn ‘sollag onuRg ‘sollog ouIny *(0G61) preg “SHINAS “M'S'N ‘suoyspurg ueuoopuny, SS SS ‘sollog SULyMe eT ‘sallag osueg ‘sollag omnod “SolIOg Sst x “Sollag MBTPIe'T ‘quOysowMTT =Sulmdsmog ‘sqTVyS vyjepurlieg “Ped PIGOTT, 1aMo'T = “aUOJSOUNIT UNL “soTeys sog yor[q_ “ped PIGOTT ATPPUAL ‘quoyspueg pur 9}VIBULO[SUOD ‘aTeyg peg oyqopay, reddy) So) vIDULO[SUOD pu sauoyspues ‘sayeyg solleg ouIn_, “(FS6T) aUMOIg “VY ‘I “SSVA “auoyspurg [ITH duieg “gmoyspurg WH dure ‘aPwYS sport 0724S ‘ayeyg JouIM, UOIYCULIO, IPISIOAIY ‘oreus THA AIO ‘dnoiy vilequeg ‘spog s,uyor “4S ‘ayTPOAYY, QUKSv2T_ “FIA *s[osuIoO plo O[Suo[OW “quOyspueg O[DUOLO]L “UO vUlIO, TOAIY O[SUOTOW “UOIVUIO UOYyRy ‘dnory uneqirey *SolUBOIOA ULYveq “UOIVUIO ST elu] esIe A ‘dno TH pow “(PS6T) HIdQ “VUUTANVD “‘spoq uoyonog UOT} CULIO Ao IOW “(SG6T) said “NVAGANVENY “NVIWATIS ‘dq TIaVL “UOTYVULIO, Bjooquiey) “WOIVULIOT ‘eUIUe Ny “UOTJVULIOT BIPTUL]Y “(ZG6T) urdor “VUANIMONVO, -NOLONITIEM “OquUloyW 9uo}soUll'T yaolg ospug “UOTYLULIO erenurg “areus aORTTRM “(Z6T) wmeyyord pue suaacjg i: (cic e109) aT woe “dno S joqdurg --¢£—é-- ‘dnory OTULUIN IPT, ‘dnory eavimMg “(ec6) WOyURyS ‘vovuNng Storm a) S.NVWGSIM “OVBIS “auo}spurg “UOIPRULIO, LIN NT ‘dnoiy reqoo ‘dnory ‘ws'O “yoy 9TFTO AA “sy UaUIpag poyerpUoLOB pul) ‘quoysouIT AIOYOOY ‘dnory Yury, 921[P “(OS61) MIPIOL a: 06: 0079) FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. 173 As was the case with the Ordovician sediments, it is apparent that there were two different types of deposition area, possibly miogeosynclinal to the west and eugeosynclinal to the east. The actual positions of the troughs were not quite the same, as evidenced by the unconformities which have been recognized. Devonian. Clarke (1878, p. 17), following the determination of the age of fossils sent overseas by him, was able to show that Devonian rocks were well represented in N.S.W. He wrote (p. 21): ‘*. . . it may be well to mention that there seems to be in parts of the Western Districts an exhibition of rocks which resemble in various ways the conglomerates of the Old Red Sandstone of Hurope; such overlie the marine Upper Silurian beds in the neighbourhood of Wellington and are known to contain Lepidodendra.” Subsequent work in the Wellington District and southward through Molong to Canowindra was summarized by G. A. Joplin (1952), who listed the Devonian sequence as follows : Upper Devonian. Catombal Formation—consisting of conglomerates, quartzites and red shales. Lower to Middle Devonian. Garra Beds, consisting of rhythmically bedded limestones and shales. Rhyolites. Further work may eventually lead to the division of the Garra Beds into at least two formations. Packham (1953), in describing Hadrophyllum wellingtonense from the Garra Beds, noted that closely related species from south-east Asia came from a position about the Lower-Middle Devonian boundary. Slight unconformities have been recognized, one between Silurian and Lower Devonian, and another between rocks of Middle and Upper Devonian age. I. A. Browne (1954), from Clarke’s collecting-ground of Taemas and Cavan, noted a thickness of at least 2,500 feet of rhyolites, andesites and tuffs, which she had earlier called the Black Range Series (Brown, 1940), followed by 2,000 feet of Middle Devonian fossiliferous limestone and clastic sediments. These were called the Murrumbidgee Beds by C. A. Sussmilch (1914) and the Taemas Series by David (1950). A. A. Opik (1954, p. 46) recorded the presence of the Ainslie Voleanics and Narrabundah Ashstone from the Australian Capital Territory. Stevens and Packham (1952) divided the beds of Four-Mile Creek south-west of Orange into: Black Rock Sandstone. Bulls’ Camp Rhyolite. Wallace Shale. The Wallace Shale, which is apparently conformable with the brown shales of the Silurian Panuara Formation, occurs also in the Spring and Quarry Creeks area. Benson (1912-1917) dealt very fully with the Devonian rocks of the Great Serpentine Belt Area between Warialda and Nundle, and I. A. Brown added to our knowledge by her careful work around Attunga (1942) and by her sub- mission of fossils to D. Hill, who described them and showed that the Nemingha limestone was probably Lower Devonian in age (Hill, 1942a). “ueyuUrpay) “uvIZyUe[qGoD “9UOjSOUIT evysUTUIa NT “URIUIANO’ “QUOYSOUITT IOOTNG ral = “URIJBAT “sollog g iS “QUOJSOUITT YaeIQ s1O0p ° YQIOMUIR I, qm z, ‘dnory yWomuey, < ee 4 A “UOTYVUIOT UIMpleg “uelUsel iy "Solas “uRIuuete ‘qUOISPH]Y Vqvivg eqeiieg ‘dnory eye, “(OS6T) “(uostag WOT pas[Acy) “SHOVLS pred AOSIOA Nvadoung “HLUOMAV LT “HIMOMNV 174 “ayoAyy aqqoAyy duep sing “‘spog eiiey “UOTJVULIO Tequioyep ‘quoysputg Yooy yoryg *BOIUBOTOA OT[SUTY ‘quoysysy YepunqeiseN “AIAYdIOg Ivuryy ‘ayIzyIeNg poueuny “(bS6T) mIdQ ‘VUNAANVO “say TTOAUY “Sp. ‘soliag osuey yori “QUOJSOWITT IOMO'T “syny, ouly ‘guojsomryT JoddyQ ‘sollag svulevy, “(FS6T) auUMOIg “VW 'T “ACN AIAN OUUOW “(ZS6T) (ZS6T) p ja urdor wuvyyIVg pue susaayg “DSNOTOW-NOLONITTAM “MGGUD ATI WOO ‘NVINOADG ‘O H1avL FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. 175 Further work on the Devonian rocks, particularly during the last five years, has made it desirable to name the sequence in terms of the stratigraphic code. The Lower and Middle Devonian sequence, which was called the Tamworth Series by Benson (1913a), should now be called the Tamworth Group, as Benson (1913-1917) described a number of rock units which may be regarded as having formation status. Among these are the Moore Creek Limestone, Loomberah Limestone, Nemingha Limestone, Silver Gully Agglomerate and Nemingha Red Breccia. Itis expected that work at present proceeding in the Nundle, Tamworth and Attunga districts will soon yield a comprehensive picture of the sequence. As shown in another publication the overlying portion of the Devonian succession, called by Benson (1913a) the Baldwin Agglomerate, is made up of a variety of rocks of which coarse beds are only a minor, if conspicuous, part. It is proposed to name it the Baldwin Formation. Near Manilla the sudden change from coarse beds to mudstones is so well marked that it shows up physiographically and is an easily mapped junction. The Barraba Mudstone is acceptable as a formation name and is taken to include all the strata up to the base of the Burindi Group. Both formations, which contain similar sedimentary types but in different proportions, are included in the Manilla Group. Osborne, Jopling and Lancaster (1948) described the sediments around Timor, east of Murrurundi, including the Timor Limestone, 760 feet thick. These beds appear to be southern continuations of the Tamworth and Manilla groups. While there are certain similarities in the faunas and lithology of the Middle Devonian sediments between the Murrumbidgee and Tamworth provinces, there are big differences in the deposits of Upper Devonian rocks in the western and north-eastern portions of the State. Undoubtedly very different conditions prevailed, as already explained by I. A. Brown (1932, p. 329). Carboniferous. The main contributions to our knowledge of Carboniferous stratigraphy since 1947 were made by G. D. Osborne (1949, 1950), who discussed the occurrence of ignimbrites in the Hunter-Karuah District and dealt very fully with the structural evolution of the Hunter-Manning-Myall Province. He described a number of sequences, but did not assemble his earlier work in the terms of the code of stratigraphic nomenclature. The individual Carboniferous strata between Raymond Terrace and Gunnedah have been mapped in some detail but no one has yet published any list of formations and groups. This will shortly be done for the Rangari-Wean area west of Manilla by B. Engel and K. Williams. In spite of all the work carried out difficulties in nomenclature are still great. They arose originally from the introduction of the name Kuttung Series for rocks in the Hunter Valley, thought to correspond with the Rocky Creek Conglomerates of Benson (1913), by David and Sussmilch (1919). The Walla- robba Conglomerates did not correspond with the basal Rocky Creek Con- glomerates as Benson, Dun and Browne had previously agreed was a possibility, but were much lower in the succession (Benson, Dun and Browne, 1920, p. 287). Carey and Browne (1938), recognizing this overlap, suggested the nomenclature which has been used ever since. Terrestrial. Marine. Upper Kuttung Series. Lower Kuttung Series. Upper Burindi Series. — Lower Burindi Series. 176 ALAN H. VOISEY. They stated (pp. 592-593): ‘‘ The names Kuttung and Burindi are so well known and entrenched in Australian geological literature that it seems inadvisable to change them; the former name too has always connoted terrestrial and the latter marine deposition and this significance is preserved in the modified nomen- clature.” Although they recognized the presence of some marine intercalations in the Lower Kuttung, these have since been found also in Upper Kuttung beds in a number of places (see Voisey, 1939a, p. 247 ; Scott, 1947, p. 229; Osborne, 1950, pp. 12-13). It would seem, therefore, that there is little reason now to place much emphasis on the suggestion that the Kuttung beds are terrestrial. There was, however, a notable change in the nature of the sedimentation in most areas at the end of Lower Burindi time. When asked to write an article on the Gondwana System in New South Wales for the 19th International Geological Congress in Algiers in 1952, I thought it better, in the absence of other rock names, to use the term ‘ group ”’ instead of ‘‘ series’ for divisions of the Carboniferous sequence, and so described the Upper Kuttung, Lower Kuttung, Upper Burindi and Lower Burindi groups. The names Burindi and Kuttung have therefore been used in both the rock and time-rock sense, and also to indicate differences in facies. Because of the inclusion of the words ‘‘ upper ” and ‘‘ lower ’’, they do not conform to the code as rock-terms but would still be acceptable as time-rock-terms. The suggestion is made that they be so retained for the present. Rock terms for the various formations will be decided upon by future workers, and the names of Kuttung and Burindi may be used in some way, preferably in the areas where they were originally defined. More satisfactory progress has been made in the paleontology of the formations, and more secure correlations with European and North American sequences have already emerged. Crockford (1947), after a study of the bryozoan faunas from the Lower Burindi mudstones, suggested a correlation with the Osagean of North America and, hence, with the Tournaisian of Europe. Work done on the brachiopods and corals from the northern end of the Werrie Basin by Campbell (1957) has confirmed an Upper Tournaisian age for the higher parts of the Lower Burindi mudstones in that area. Previously Delépine (1941) had suggested an Upper Tournaisian age for a goniatite assemblage from the lower part of the Burindi mudstones in the same vicinity previously regarded by Brown as Lower Tournaisian (Carey, 1937, p. 353). The evidence of the brachiopods suggests that the age determined by Delépine is too young, and further support comes from a partial reassessment of the goniatite evidence by Miller and Collinson (1951). The closest affinities of these faunas appear to be with those of North America, though there remain clear connections with Western Europe and North Africa also. The bryozoans from the marine intercalations in the Lower Kuttung at Rouchel Brook (Crockford, 1948, 1951) are very similar to those from the upper part of the Lower Burindi mudstone. However, the Phricodothyris described from this locality by Campbell (1951) is quite distinctive. The so-called Productus barringtonensis from beds in the Gloucester Trough mapped byme as Upper Burindi (Voisey, 1940) is now known to belong to the genus Marginirugus, which in North America is restricted to a horizon near the Tournaisian-Visean boundary. The form was known only from the lower North Coast of New South Wales, until Traves (1955) recorded that the genus was recognized by Opik from the Septimus Limestone in Western Australia. This suggests that the coarse sedimentation of the Lower Kuttung-Upper Burindi type may have commenced earlier in the Gloucester area than in the Werrie Basin. t= FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. “uvISsIeUIMoy, “UvasTA “URLMUIe N “ULIAODSOP “SHDVLS Nvadouny *Sorlog Ipulmg JoMoT *sollag tpulmg eddy *SOlIag sunyjny JIaMoT *sallag dunyny rioddy (8861) sUuMOIG pue AdIVD “SaTUaS “M’'S'N ‘dnoiy Ipurmg JaMoT “dno Ipuying Joddp *sollog TysURUOOg ‘dnory sunyyny IMoT “dno sunjyny reddy ‘sollog oUlyeTIN ‘soldeg ipulmg *SOlIag Sunjjny IaMo'T *soTI0g sunyjyny JoddgQ ‘sollog rpuung ‘aseyg [eseg "adRYG OIUBITOA ‘adeyg TePLTD ‘sollag Sungyny *(ZZ6T) auIogsO *NOSUMLVd -NMOLAONTUVTD ‘salieg rpurmg ‘spog VqqorRyTe A “spo Yoorg $,uIeyy “sped auoysuyor “I “‘spog [eDeID ‘sollog sunny (6161) YoTIuissng pue plavqg UGAIY UINAW (Z¢61) (FE61) (LE61) AQslOA AQSIOA Avie “MSN “HVAVSSAA “WIndoavUNay) “‘SUOTIYLULIO ShoOJasMoqivy oy} JO IINyLpOUIWION UI sedueYyO SUIMOYS ‘SNOUATINOTUVO ‘d aiav ‘salog rpuLmg "soy BIOULO[SU0D yoorg ANY (161) uosueg “MGGUN AMOOY 178 ALAN H. VOISEY. The only recent work on faunas higher in the Carboniferous is that of Crockford (1948, 1951), who concluded that a cryptostomate bryozoan fauna from a horizon mapped by Osborne (1950) in the upper glacials of the Upper Kuttung was closely comparable with that of the Neerkol Series of Queensland. Hence, a correlation with the Moscovian was suggested. Maxwell (1951) made reference to Neerkol brachiopods in the Upper Burindi of Gloucester, Bramble Bay and the Emu Creek Series of Drake. We are thus well on the way towards establishing very close correlations with the Carboniferous rocks of North America and Europe, and it is apparent that only by the continuation of this detailed paleontological work shall we be able to define our series here in the terms agreed to by European and American geologists. A discussion of the paleogeography of Carboniferous times has been given elsewhere (Voisey, 1945 and 1957). Permian. Clarke (1878, p. 66) divided the Hunter River sequence into Upper Coal Measures. Upper Marine Beds. Lower Coal Measures. Lower Marine Beds. While advocating a Paleozoic age for them, he stated (1878, p. 36) that even in 1861 he had been willing to admit that, though some of the coal appeared to belong to the true Carboniferous epoch, some might belong to the Permian, aS was suggested by Mr. Dana. Controversy regarding the actual Carboniferous-Permian boundary was to continue for nearly 80 years longer. That it is not yet over is evidenced by D. Hill’s closing remarks in her review of Permian stratigraphy. She states (1954b, p. 104) “ It is possible, then, that in Australia also the Glossopteris flora may have entered in the Stephanian and the tendency apparent since 1951 to take the base of the Australian Permian down to include all beds with the Glossopteris flora may prove to have been ill-inspired ”’. The Geological Survey of New South Wales, following a great deal of work on the coalfields, subdivided the Hunter River sequence in terms of the code (as indicated in the Table E). The major changes are the substitution of the names ‘““Dalwood Group” and ‘ Maitland Group” for ‘‘ Upper Marine Series ”’ and “Lower Marine Series’? on the grounds that ‘‘ Upper Marine” and ‘‘ Lower Marine” are not place names (Hill, 1954b, p. 93). Hanlon, Joplin and Noakes (1953) also reorganized the nomenclature of the Illawarra District (see Table E). Hanlon (1947-48 ; see Hill, 1954b, pp. 93-94) has named the formations he had previously described from the North- western Coalfield, and Loughnan (1954) has recognized a number of formations in the Gloucester Trough. OC. T. McElroy (1957), after a detailed examination of the sediments of the Southern Coal-field, described them as well-sorted sandstones and discussed the heavy mineral assemblages. E. K. Sturmfels (1950) recorded Glossopteris and Noeggerathiopsis from the Oaklands-Coorabin Coalfield and noted that I. Crespin had identified Hyper- amminoides cf. aucula Parr and Ammodiscus cf. milletianus Chapman. The Permian sediments in the Ashford Coalfield were examined by H. B. Owen and G. M. Burton (1954), and detailed sections were listed, but the sequence was not divided into formations and groups. 179 FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. “UBIIVUIALE “URINSUIIV “uvlmMsun yz “UeIUeZzB yy “UvICIIV], “SHOVIS NVISSOY ‘sollag aulIey, IaMoT “somnsvoyy [vo9 JOMOT *BaIIOg oulieyy, Jedd “soImsvoyy jeog reddy “(OS6T) pred Bice eects “M'S'N *SOTUBITO A ayvid “solysepooIA preity ‘dnory SIH yoraeyp “UOTeULIO JOATY JOVIvICD “gu0ySpN]L, AIMS) ‘dnoiy Yoo100g *AQSIOA “aaVUd -100u00q uOleUMIO gg Yoo) 8, F1VL *9U0}SOUIN'T yeqesse x “U01yeUlIO,] OIQIV AA ‘dnoiy Avaporyy *£OSIOA “UHAIY AVATIOVIN “UOlVULIO, Hqury “9u0}SOUN'T Ayied Iepap “uo spn aureljog ‘dnoiy suruueyy “UOIJVUIIO,T suviIMoq “soInsvay{ jeop woay ou ‘ay e1OULO[SUOD JOAIY S,pIe A “sonsvay [eop WeAvID OUT, *9ye1OULO[SUOD yeorig sutdg “UOTIVULIOT Ay prorg “(FS6T) *KOSIOA uvuysnoT “MMA ‘aTaIATVOD ONINNVIV UALSHONOTY “NVINUd ICeUCKAR ‘dnory twi10J, “sy[esegd olla (A “SoIMSBo]L Teo) Y90I STIIOM “UOI}VULIO ourdno10g “UOTJVULIO auoyspely “UOTyRULIO your Youd “(QPS61) INH. Ur ‘uopuey “aTa1ATVOD LSAaM-HLYON “MOIyeULIO IVAUIYOOT “UO VULIO aepurlly UOT} VULIO psojr9yyNYy “uOTyVULIO,, ATE] ‘dnory poompeq ‘soMsvay{ [GOD vyeTH “UOTYVULIO,T Ol[SIOPTA ‘UOIyeULIO PIOJ[Og “UOIYEULIO,, 9OIN ‘dnorg-qng uoyxuvig “UOTYVULIO,, SULIGINL ‘dnorg purlyeyy ‘sommsvopl [GON OSVUMOT, “*somsvoyT Teog eyseoMeN “(QFS61) TH Ur “Amg “T0399 “M'S'N AGAIY ULNA “‘soInsvayy [VOD epATO “9T048}IS UBIPULMEIPUL MA “QUOJSPURS BIMON ‘ayeys Aljog ‘dnorg waaryyeoyg ‘pny, woyysnoig “OyyeT YoVqo[Ppes ‘aqye’T elie moquiey *soTUvOTOA BUOSULIIOD Oye'T elImueuulyy ‘oyqey Apyplog ‘Puy ureyunoy_ voqeyiddvy, ‘soInsvay [eog eIIVMeTIT “(SG61L) SOHVON pue uldoe ‘uojuey ‘VUUVMVTTT 180 ALAN H. VOISEY. In order to bring my own work on the North Coast (Voisey, 1934-1950) into line with the code and to correlate the beds with those of the Hunter River District, I suggest the following scheme, which will be discussed in another publication. Hunter River. Manning River. Macleay River. Dalwood Group Manning Group Macleay Group Farley Formation Colraine Mudstone Warbro Formation Rutherford Formation Allandale Formation Cedar Party Limestone Yessabah Limestone Lochinvar Formation Kimbriki Formation Tait’s Creek Formation The rocks of the Boorook-Drake area in the County of Buller are also being renamed as follows : Boorook Group. Gilgurry Mudstone .. es ae S46 .. 1000 ft. Cataract River Formation .. me a oe SISlORtt: Cheviot Hills Group. Girard Pyroclastics. Drake Volcanics. The Plumbago Creek Series (Voisey, 19365, p. 162 ; 1939c), which in future will become the Plumbago Creek Beds, was recently re-examined and found to contain definite Permian fossils. These were identified by K. S. W. Campbell as follows: Anidanthus springsurensis Booker, Strophalosia cf. preovalis Maxwell, Terrakea sp., Aviculopecten sp., Stenopora sp., Fenestella sp. and Polypora sp. These occur in rocks exposed in a gully about a mile north-west of the lime- kilns on the Tabulam-Pretty Gully Road. Because of the intervening granite intruding the beds, their relations with the Boorook and Cheviot Hills groups have not been determined, but the fossils indicate that they should be low in the section. Permian sedimentary formations are probably much more widespread in north-eastern N.S.W. than has previously been supposed. They occur at least at intervals in a belt running from the vicinity of Mt. Jasper in the watershed of the Hastings River through the Mooraback area, where in Limestone Creek limestones are exposed. They appear again in rugged country around Hall’s Peak, where they are associated with flows of rhyolite and andesite. Permian fossils were found in a limestone boulder in the neighbourhood of Jeogla, 33 miles east of Armidale, by W. Anderson (R. Etheridge, Junr., 1888 ; Andrews, 1908). They were found in situ a few years ago by Mr. Maurice Wyndham in Oaky Creek and in a number of other places to the north. An extensive occurrence near the Devil’s Chimney in the gorge of Kangaroo Creek, Aberfoyle, is said to have been visited by Professor David nearly 60 years ago. Fossils identified by H. O. Fletcher from Jeogla include Linoproductus cora var. farleyensis (Eth.), Spirifer cf. duodecimcostata McCoy, Spirifer stokesi Koninck, Spirifer vespertilio Sowerby, Dielasma sacculum var. hastata (Sowerby), Pleuro- tomaria morrisiana McCoy, Conularia levigata Morris. The beds around the Oaky Creek Dam Site were mapped by E. J. Harrison (1949, p. 70). FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. 181 Because of the intense folding and faulting in New England it is very difficult to separate the various formations, and it is thought that much of the rock hitherto regarded as being Lower Paleozoic and resembling the Brisbane Meta- morphics, will turn out to be Upper Paleozoic. Triassic. It was Clarke who named the sandstones around Sydney the Hawkesbury Sandstones, and the shales above them the Wianamatta Beds (1878, p. 70). These names have been retained in the revised form of the Triassic sequence as given by Hanlon, Osborne and Raggatt in 1953. Table F shows the details of the recently accepted nomenclature. Osborne (1948), in an excellent review of the stratigraphy of the Sydney Basin, brought together earlier work, illustrating his treatment by means of a number of measured sections. He also dealt with the nature of the sediments and their structures and discussed the possible environments under which they were formed. Lovering (1954) subdivided the Wianamatta Group, and Crook (1956) detailed the formations of the Narrabeen Group outcropping in the Grose River District, applying the principles set out by Packham (1954) in the classification of the sediments and discussing the depositional conditions. J. Rade (1953, p. 153; 1954a, p. 42) gave the name Gunnee Beds to grey, gritty sandstones with shales 100 feet thick in the Delungra area (Portion 42,. Ph. Gunnee) recording from them Thinnfeldia odontopteroides (Morris), T. lancifolia (Morris), T. feistmanteli (Johnston), Johnstonia coriacea (Johnston); and Stenopteris elongata (Carruthers). He pointed out that available bore-logs: indicated that the Triassic sediments thinned out quickly towards the west. Triassic beds are known to outcrop southward towards Gunnedah around the eastern margin of the Artesian Basin. Some well-preserved plant remains were shown to me recently by Mr. C. R. McWilliams on his property ‘‘ Grey- lands’, near Turrawan, in beds immediately overlying the Permian Coal Measures. Jurassic. Rade (1954a, 1954b) described some of the Jurassic rocks in the Warialda and Coonamble areas assigning to some of them a Walloon age, but did not apply any formation names. Wade (1953) described some Jurassic fishes from N.S.W. but did not give details of their stratigraphical occurrence. : There is a great deal of work to be done on the beds of the Clarence Basin and the Jurassic sediments fringing the Artesian Basin. It is not possible at: present to give any list of the formations. Cretaceous. Rade (1954a, 1954b) referred to the Cretaceous sediments in the Artesian Basin in New South Wales. Crespin (1955) listed the Lower Cretaceous foraminifera derived from bores in northern New South Wales, mentioning 102 genera and species, most of them arenaceous forms. She suggested that the assemblages indicated deposition in a near-shore, shallow, brackish-water environment. Tertiary. Little has been written of Tertiary sediments in the past decade, but names have been given to a number of lava flows and pyroclastic rocks, notably by Hanlon, Joplin and Noakes (1954) for the Illawarra District and by Crook and McGarity (1955) for the Minynon Falls District. ALAN H. VOISEY. 182 ‘royUNg JaMo'T ‘rayung iaddgq ‘rodnay orpaRyA “‘SHDVLS NVaaoungy ‘sallag wseqviIeN ‘sollag AINQsoyMeVPT ‘SoLIOg VIYVUICUI AA “(OS6T) pred “‘SaIUag SHTVA HLQ0S MIN “eyoVMAIND HIp[Vop *JoquIayY ayoVMAIIH P10J3O ‘greys BITequUIOM ayovmAaT) YSNoIOGIvog qUOysARIO WAV [oaurys ‘ayoemAdIN Os[Ng ‘quoysAUI) TH PIV ‘dnorp-qng wot “UOI}VULIO,, PIOJsoy ‘dnory woeqeiieNn ‘TOQUE, suOYspuKg vjOopug ‘guoyspueg AIMQsoyMeyL ‘(9S6T) UoTURHT * (Sc6T) 4yessey-aulogsg-uojue A “LSVOD HLAOS ‘oyeoulo]su0g YyeIowUNy, “UOTFVULIO,, YelessNy, guoysAv[Q AoIe[OD ‘dnoiy-qng Woy *IOQUIBI PUOYSpuURyg FUCA A *TOQUIOTL auoyspursg YyequIMa *TOQUIdTL aUOJSpULE VAOISURTL “UOLYBULIO,. PIOJSOH ‘dnory wooqeiie Nn ‘euojspueg AInqsoyaepy (E61) 4yvasey-eu10gsQ-uopuRe A “SNOAM-NOUFAVUUVN ‘uoryeUlIOg Ao[eg “QUOJSPUBS ISOI “(raquo auOspueg Svivqey, ATA) UOTVUMIO MOTRIN ‘dnory weeqeilien ‘quoyspueg AIMQsoyMeE_L —_ a ‘dnory useqviren “OJIZJIVNDOYJAO IAISSLIL ‘spog onussed ‘quoyspurg AIMQsoyMeAy “aIeuS PPVUSV ‘auoyspueg AINQUIYOUTTT ‘greys ATesurrg ‘dnory vyyvUeUel AA *(9S6T) YOoIg “ASOUD-OTOD ‘OISSVIUM.L ‘a QTAVI, ‘ereys PPeyusV ‘quojspurg AINquIyoUrpYy ‘ayeys Ayjesulig ‘dnor-qng [ood19aryt ‘ouoyspues TH 8.3300 ‘ayeyg uvuuy ‘QUOyspuURg Youqiozeyy “UOIVULIO WOT ‘eeyg soypnid ‘dnory-qng uapure9 ‘dnory v)}eureurl A ‘(FS6T) SULIIAOT “NISVG AANCAS FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. 183 Pleistocene. Vallance (1953b) described the finding of varved clays in the valley of Trapyard Creek in the Kosciusko district by W. R. Browne and D. G. Moye. This was the first record of Pleistocene varved glacial deposits in New South Wales. THE FUTURE. An examination of our knowledge of the sedimentary formations of New South Wales reveals that there are many gaps. These occur primarily because there have been so few workers. Even those who are most interested actually spend comparatively short periods in the field. I feel that as a group none of us should feel satisfied with the collective effort in the last ten years. It is true to say that a large part of the work has been done by University staff and students. Because of the necessity for such investigations to yield tangible results, there has been a conscious selection of areas known to be mappable and to contain a variety of interesting rocks. Officers of the N.S.W. Geological Survey have been dealing principally with coal-bearing areas, so far as stratigraphical work is concerned. Others have studied fracture-patterns and aspects of ore deposition, and have not been able to spend time on stratigraphical work. As a result of the selection of areas for special reasons we find that we know a great deal about the lacustrine and shelf deposits. The miogeosynclinal and exogeosynclinal areas of the Central West and the coal-fields have been well studied. We know relatively little about the eugeosynclinal deposits, apart from scrappy notes in a large number of reports. While we have been struggling to find what rocks actually exist in New South Wales, big advances in the study of sedimentary formations have been made overseas, particularly in America, because of their importance in the search for oil. Even there work has been much more concentrated upon continental and miogeosynclinal areas than upon the contents of the eugeosynclines. In Australia, we have been particularly handicapped by the comparative scarcity of sub-surface information. Unless the search for oil is successful and work on sedimentary formations is encouraged, we do not stand much chance of rectifying this position. One must hope that it will be possible to expand the personnel and facilities of the State Geological Survey, so that it will be able to embark on a programme of systematic mapping in co-operation with the Commonwealth Bureau of Mineral Resources. In the United States there exists close liaison not only between the U.S. Geological Survey and the state surveys, but also between both and the Universities. The procedure adopted in both the United States and Canada, whereby some members of the University staffs work with the Surveys during vacations, and conversely certain survey officers are invited to spend some time in the Universities, has a lot to recommend it. The use of University students by the Surveys during vacations is a step in the right direction. Very little mapping has yet been done in this State from aerial photographs, but their use in the future should greatly expedite the completion of map sheets and add to their accuracy. The efficient functioning of the Survey Service of the Australian Military Forces at Victoria Barracks and the Air Photo Library of the N.S.W. Department of Lands, to both of which all members of my depart- ment are heavily indebted, should now make this possible. Apart from the economic necessity in relation to our resources of coal, petroleum and the non-metals, the regional mapping of the State is a necessary basis for all other geological investigations. 184. ALAN H. VOISEY. As pointed out by Krumbein and Sloss (1951, p. 4), there are two principal aspects of stratigraphy, one physical relating to the rocks and their characteristics, and the other involving the study of paleontology. Through the former we proceed to lithological correlation and sedimentary tectonics, and through the latter to the study of organic evolution. From both we determine the history of an area and build up the paleogeography. Recent papers show that the paleontologists are becoming more precise in their work, thus enabling us to make closer correlations with overseas sequences in the manner attempted by Clarke. On the other hand, we have a tremendous amount of sedimentary petrology ahead of us. Rock names given in the past have usually been those determined in the field, and when one attempts to use the data for environmental studies the shortcomings are most noticeable. The kind of work being carried out by Packham (1954), Lovering (1954), Crook (1954, 1956) and McElroy (1957) is a necessary part of our stratigraphical investigations, and must be done before any really reliable data on sedimentary facies and sedimentary tectonics can be assembled. Not only must agreement be reached on rock classification, but details of sedimentary structures, as indicated by Packham (1954), must be recorded. The future should see much more accurate mapping, more sedimentary petrology and a continuation of the good work being done in paleontology. An absorbing story is contained in the sedimentary formations of New South Wales and we, like Rev. W. B. Clarke, must seek by diligence and perseverance to read it. BIBLIOGRAPHY. Andrews, E. C., 1908. Report on the Drake Gold and Copper Field. N.S.W. Geol. Surv., Rpt. No. 12. Andrews, P. B., 1949. Stratigraphy and Physiography of the Gloucester District. THis JoURNAL, 83, 1-7. Basnett, E. M., and Colditz, M. J., 1945. General Geology of the Wellington District, N.S.W. Ibid., 79, 37-47. Benson, W. N., 1912. Geology of the Nundle District, near Tamworth, N.S.W. Rpt. A.A.A. Scz., 12, 100-106. -—- 1913-17. Geology and Petrology of the Great Serpentine Belt of N.S.W. —-—-———— _ 1913a. (i) Introduction. Proc. Linn. Soc. N.S.W., 38, 490-517. —-—-————— 1913b. (ii) Nundle District. Jbid., 569-596. 1913c. (iii) Petrology. Ibid., 662-724. —-—-————— 19l5a. (iv) Dolerites, etc., of Nundle. IJbid., 40, 122-171. —-—-————— 1915b. (v) Geology of Tamworth. Jbid., 540-642. —-—-————— 1917a. (vi) Geology of Western Slopes, etc. Ibid., 42, 224-283. 1917b. (vii) Geology of Loomberah District, ete. Ibzd., 320-394. Benson, W. N., Dun, W.S., and Browne, W. R., 1920. (ix) Geology of the Currabubula District, [bid., 45, 285, 337, 405. Booker, F. W., Bursill, A., and McElroy, C. T., 1953. Sedimentation of the Tomago Coal Measures in the Singleton-Muswellbrook Coalfield. THis JourNAL, 87, 137-151. Brown, I. A., 1932. Late Middle Devonian Diastrophism in South-eastern Australia. Proc. Linn. Soc. N.S.W., 67, 323-331. —-—_—— 1940. Stratigraphy and Structure of the Silurian and Devonian Rocks of the Yass-Bowning District, N.S.W. Turis JourNnatL, 74, 312-341. 1942. The Tamworth Series near Attunga, N.S.W. Tus JOURNAL, 76, 165-176. Brown, I. A., and Sherrard, K. M., 1951. Graptolite Zones in the Silurian of the Yass-Bowning District of N.S.W. Tuts JOURNAL, 85, 127-134. Browne, I. A., 1952. Ordovician Limestone at Bowan Park, N.S.W. A. J. Sez., 15 (1), 29. 1954. Presidential Address. The Tasman Geosyncline in the Region of Yass, N.S.W. Tuts Journat, 88, 3-11. Browne, W. R., 1949. Some Thoughts on the Division of the Geological Record, etc. Pres. Add., Sec. C, A.N.Z.A.A.S. Rpt., 27, 35-46. Campbell, K. S. W., 1955. Phricodothyris in New South Wales. Geol, Mag., 92, 374-384. - 1956. Some Carboniferous Productid Brachiopods from N.S.W. Jour. Paleontology, 30, 463-480. FURTHER REMARKS ON THE SEDIMENTARY FORMATIONS OF N.S.W. 185 Campbell, K. 8. W., 1957. An Upper Tournaisian Coral-Brachiopod Fauna from N.S.W. Jbid., 31, 34-97. Carey, S. W., 1934. The Geological Structure of the Werrie Basin. Proc. Linn. Soc. N.S.W., 59, 351-379. —-————— 1937. The Carboniferous Sequence in the Werrie Basin. Jbid., 62, 341-376. Carey, S. W., and Osborne, G. D., 1938. Nature of the Stresses Involved in Late Palaeozoic Diastrophism in N.S.W. Tuts JouRNAL, 72, 199. Carey, S. W., and Browne, W. R., 1938. Review of the Carboniferous Stratigraphy, etc., of N.S.W. and Q’ld. Tuts Journat, 71, 591-614. Clarke, W. B., 1878. Remarks on the Sedimentary Formations of New South Wales. 4e. Govt. Printer, Sydney. Colditz, M. J., 1948. Petrology of the Silurian Voleanic Sequence at Wellington, N.S.W. Tuts JOURNAL, 81, 180-197. Crespin, I., 1955. Lower Cretaceous Foraminifera in Bores in the Great Artesian Basin, Northern N.S.W. TuHis JouRNAL, 89, 78-84. Crockford, J., 1947. Bryozoa from the Lower Carboniferous of New South Wales and Queensland. Proc. Linn. Soc. N.S.W., 72, 1. 1948. Bryozoa from the Upper Carboniferous of Queensland and N.S.W. Jbid., 73, 419-429. ——————_ 1951. Bryozoan Faunas in the Upper Paleozoic of Australia. Ibid., 76, 105-122. Crook, K. A. W., 1954. Petrology of the Greywacke Suite Sediments from the Turon River- Coolamigal Creek District, N.S.W. Turis JouRNAL, 88, 97-105. 1956. Stratigraphy and Petrology of the Narrabeen Group in the Grose River District. Tuts JouRNAL, 90, 61-79. Crook, K. A. W., and McGarity, J. W., 1955. The Volcanic Stratigraphy of the Minynon Falls District, N.S.W. TxHis JouRNAL, 89, 212-218. David, T. W. E., 1896. Radiolaria in Paleozoic Rock in New South Wales. Proc. Linn. Soc. N.S.W., 21, 553-570. 1950. The Geology of the Commonwealth of Australia. Edward Arnold, London. David, T. W. E., and Sussmilch, C. A., 1919. Sequence, Glaciation and Correlation of the Carboniferous Rocks of the Hunter River District, N.S.W. THis JouRNAL, 53, 246-338. Delépine, G., 1941. Upper Tournaisian Goniatites from N.S.W. Ann. Mag. Nat. Hist., 7, 386. Etheridge, R., Junr., 1888. Permian at Jeogla Falls, New England. 0” in place of “ s=u” in the enunciation of Theorem W. Now recalling that | «#J,(«) | has a finite upper bound M, ae a>0, that | at Vy (x) oe a finite upper bound ay v(%) for a> a > 0, that Ona )>0 for «>0, that | Jy(«)|0 and referring . the asymptotic estimates in the neighbourhood of the origin, we see that we can choose an a, so that when 0 a%. So we have proved that S, is uniformly bounded if 00. Only a slight modification in the above proof is required for v=0, and a similar method may be applied to show that S, is also uniformly bounded. |S] < REFERENCES. Griffith, J. L., 1956. ‘‘ On Weber Transforms.’ THIs JOURNAL, 89, 232-248. R. P. Boas, Jnr., 1957. Review of above paper. Math. Reviews, 18 (6), p. 481. ON THE ZEROS OF A CERTAIN FUNCTION INVOLVING BESSEL FUNCTIONS. By JAMES L. GRIFFITH. New South Wales University of Technology, Sydney. With two Text-figures. Manuscript received, November 11, 1957. Read, December 4, 1957. In a paper published some time ago (Griffith, 1957) I stated, without proof, some facts concerning the distribution of the zeros of w(z, C, v)=w(z)=2H 9? (2) CHM (2), ve0,. .-..-- (1)* where C is a real constant. The results quoted were sufficient for the needs of the paper. I submit in what follows an analysis of the zeros of w(z) for —4n Sarg 2--C(C —2v)=0. Now C and y are real, and we see that this proves our assertion. To obtain many of our results we write w(2)=2Hy” (2)C(2), where Hyiite) 0 C(z) = ae SIGH Fo oleela nies welasieres (3) and examine the change in arg C(z) as 2 passes around certain contours. Thus, account must be taken of the zeros of HS)(z). Combining information supplied in Erdélyi (1953, p. 62) and Watson (1953, p. 511), we obtain A. (a) H(z) has no zeros if 05n. (c) If v—} is an odd integer 2k—1, then HS” (z) has k —1 zeros in each of the ‘ 3 : regions —3m0; 2 C | bees {| +00yh »=0 C(@)~ a EN Pe Shoo (6) Ge [1+0(1)], v0 as |2|>0; when z=a2> 0 Hyti(2) Jy 41(w)Io(w) + ¥, 41(@)¥y(w) —2i(rea)-? | (7) HSY (2) [Jy(@) }? ++[¥(x) ? As ah when z=re'", r>0 Aya (@)_— Jy arlr)Iv(r) —Yy 41 (0) V(r) —2i(er)-} (8) H(z) [ASE see) a) § hae he Apa Text-fig. 1. when xv=te?™, t>0 w(z)=(47i)“e-P[tK, 41(t) CH (t)]; «0... ee eee (9) when z=we-i™, u>0 HY) ,(2)__ 7 cos vx. u-1 iP (10) HO (2) = GER es ere where P= {rl 41(u)Ly(u) —K, +1(u) Ky(u)} +7 sin vr Ly +1(u)K,(u) —L,(u) Ky +1(u)} and Q=[r1,(u) +8in v7rK,(w) ]? + cos? vr LK, (u) ]?. Since we have completed the case C=2v, we will assume in what follows that C42v. Since C/z is real on the real axis, equations (7) and (8) show that C(z) does not vanish on the real axis. Thus w(z) does not have a zero on the real axis. Similarly, since C/z is imaginary on the negative imaginary axis, equation (10) shows that if cos vr0 (i.e. vy—} does not equal an integer), w(z) does not have a zero on the negative real axis. We now determine the number of zeros above the real axis by examining the increase of arg C(z) as z passes around the contour in Figure 1. It will be assumed that the large semicircle 3 (with centre the origin) is sufficiently large for the estimate (5) to be valid and the small semicircle y to be small enough for the estimate (6) to hold. ZEROS OF A CERTAIN FUNCTION INVOLVING BESSEL FUNCTIONS. 193 It is then easy to see that the values of arg ¢(z) are given by the following table. C<2v C> 2v Ay we os ee —tr —t7 Ag aa oe ne —t7r —3r Ag ag sts ake —T 0 Ay ae 3 ab —tr 40 A; ae cic sc 0 ™ fle hs ah aan —in sm The increase in arg ¢(z) is zero if C<2v and is 2x if C>2y. Thus, referring back to A(a) above and recalling the symmetry of the zeros, we conclude that If C<2y, w(z) has no zero above the real axis. If C>2yv, w(z) has one and only one zero above the real axis. This is a simple zero, which lies on the positive imaginary axis. In view of equation (9), we see that we have proved incidently a rather obvious result which we will need later, viz.: tK,+1(t)—CK,(t) has one and only one real positive zero if C>2v and no real positive zero if C<2v. Now the recurrence formule (Watson, 1953, p. 79) show that tK, +1(t) OK, (t)=tK, _1(t) —(C —2v)K,(2). If we sketch the graphs of tA, _1(t) and (C —2v)K,(t) it is immediately obvious that as C —2y increases from 0 to oo, the zero moves from the origin to co. The asymptotic formule for the Bessel functions show that for large C the zero approximates to C—v—%. We now proceed to determine the distribution of the zeros of w(z), which lie below the real axis. We first assume that v—} is not an integer. Thus cos yr0, and so w(z) will have no zeros on the negative imaginary axis. Keeping Figure 1 in mind, the description of Figure 2 is obvious (See page 194). As 2 passes around the contour in Figure 2, the values of arg C(z) are given by the following table: C<2v pes DA eel C>2v cos vr>0 cos vr <0 Agia: ys —in —tr —3r Ay ate —tr —tr —tr A, -. 50 0 0 —T INS E a 40 40 —tr AY ai: ve —tr ar —tr Thus arg C(z) is unchanged except when C<2v and cos vr<0; in which case the increase is 27. So if C<2v and cos v~<0, the number of zeros of w(z) in —1x2y, then w(z) has k zeros in —in2v, one only of these must lie above the real axis, and if C<2v, then all must lie below the real axis. If we determine the number of zeros which lie on the axis, the remainder will be symmetrically placed on either side. We write z=we'", u>0 and use Erdélyi (1953), p. 5 (15) and p. 80 (45) and Watson (1953), p. 79 to put w(z) in the following forms : if v—4=2k (k an integer) OC eed om Wc 9202/1 (2) ae eon ey esto (11a) with p(u)=[WK, +1(u) —CK,(u)]—n[uly41(u) +L (u)] .... (110) =[wK,-1(u) —(C —2v) K, (uw) ]—n[ul, -1(u) +(C —2v)1,(u)].. (11e) and if vy—4=2k—1 (k an integer) w(2)= —2r-le“h + bttig(n) ww kw eee (12a) with q(u) = [vKy 41(u) —CK,(u)] +7[uly4i(u) +CL(u)] ........-. (12b) =[wK,—1(u) —(C —2v) K,(u)]+-7[uly1(u) +(C—2v)1,(u)]. — (12e) Thus to find the zeros of w(z) on the negative imaginary axis of z, we need only consider the zeros of p(w) and q(u) for positive w. It will be seen that it is necessary to treat the cases v—4 and v=14 separately. ZEROS OF A CERTAIN FUNCTION INVOLVING BESSEL FUNCTIONS. 195 With v—i, we have w(2, O, 4) = —(4mz)-be#[z —i(C —1)] with its only zero at i(@—1). When v=14, w(z, O, 14) =i(dre*) te! [22 + 12(3 —C) —(3 —C) ] and the explicit formula for the zeros may be written as 2= —i4(3 —C) +4(3 —C)(1+0)}. Except that there is a zero at the origin when C=3 (=2y), this indicates a typical result of the case v=2k—}. We have : when (C<—1, there are two negative imaginary zeros ; when C=-—1, there is a double imaginary zero (at z= —21) ; when —1<(C<3, there are no zeros in the imaginary axis ; when C>3, there are two imaginary zeros, one positive and one negative. We now assume that 02y, v=23, and consider w[wk, 1(u) —CK,(u)|=s(u)=r(v) as a function of v=w?. Then dr a= 2u’—1[wK,(u) —CK,_1(u) ] and dr dv So, obviously, 7, dr/dv and d?r/dv? each have one and only one (simple) zero. Then, keeping the asymptotic expressions for the Bessel functions in view, we observe that the graph of y=r(v) starts at a point on the negative y-axis, increases steadily, and after cutting the v-axis passes through a maximum. It then decreases to an inflexional point, at which it changes from being concave downwards to being convex downwards and then finally approaches the v-axis from above. Since w’[ul,,1(u) +C1,(u)] (as a function of v) is monotonic increasing from zero, it easily follows that q(w) has one and only one zero, but that p(w) may have no zero, a double zero or two zeros, but no more than two zeros. Now sketching the graphs of u[ Ky _—1(w) —7J, -1(u) Jand (C —2v)[K,(u) +71,(u) J, it will be seen that as C—2v increases from zero, one of the zeros of p(w) will increase from zero, while the other will decrease from the zero of K, (uw) —71,_1(u) to a common value u,(v)* with corresponding C=C;,(y). =4u—2[uwK, _1(u) —CK, -2(u) J. * We have written w,(v) and C,(v) to emphasize the fact that these values are dependent on y. c 196 JAMES L. GRIFFITH. For C>C,(v), there will be no zero on the negative imaginary axis. Now at (u,, C1) we observe that u’p(u) and its derivative will have a common zero. Thus [w, Ky —1 (Uy) —(C, —2v) Ky (uy) ] — [Ly —1 (Uy) + (0 —2v) (uy) ]=0 and [ —u, Ky (u,) +O K, 1 (44) ] — mlm Ly(uy) + OL, -1 (ty) ]=0. Eliminating K,(u,) and J,(u,) from these equations, we find that [wi —C, (0, —2v) JL, 1 (uy) — I, 1 (4) ]=0, in which the second factor is not zero. Thus (w,, C,) can be found from the point of intersection of and _ UL Ky +1(u) —TeL, +1(u) J RAGGA cn ee We now assume that C <0. We may use a method similar to that just given. We will then find that p(w) has one and only one zero, while q(wv) may have no zero, a double zero or two zeros. As C increases from —oo, then one zero of q(u) will decrease from +o, while the other will increase from the single zero of K,(u)—zJ,(u) until they coincide at w,(v) with C=C,(v). As C increases further, there will be no zero until C passes 2v. There will then be one zero (as shown above). The values of w,(v) and C,(v) can be found from the point of intersection of (13) and C o— tl) +r, +1(u)] K,(u) — ml, (u) Sije,jouia/ (a) fo leas tore csheltertedte Collecting the results, we now summarize. Omitting the cases v=} and y=13, which have been discussed above, the distribution of the zeros of w(z) when y—}=—n (n an integer) is given by the following table. Negative Positive Regions. Imaginary | Imaginary | —3™C,(v) 0 1 k C2v 1 1 k—1 REFERENCES. Erdélyi, A., and Others, 1953. ‘* Higher Transcendental Functions”, Vol. Il. MacGraw-Hill, Pub. Griffith, J. L., 1957. ‘‘ A Note on a Generalization of Weber’s Transform.’ THis JOURNAL, 90, 157. Watson, G. N., 1953. ‘‘ Theory of Bessel Functions.” Cambridge. TAPIOLITE AND THE TRI-RUTILE STRUCTURE. By F. M. QUODLING. Department of Geology and Geophysics, University of Sydney. With Plate V and two Text-figures. Manuscript received, November 19, 1957. Read, December 4, 1957. ABSTRACT. A twinned tapiolite from Strelley, Western Australia, is recorded. X-ray powder- data is given for rutile, striiverite and three tapiolites; the tri-rutile structure is discussed. A erystal from the Pilbara district, Western Australia, was presented to the Department of Geology and Geophysics, University of Sydney, some years ago. It was considered to be tantalite, but proved to be tapiolite, and as this tetragonal iron tantalate is rare, a short description of the specimen will be given. It was found at Strelley, lat. 20° 30’S., long. 118° 55’ E., in the Pilbara district, where a wealth of rare minerals has been provided by granite pegmatites ; many, including tapiolite, were described by Simpson (1917). This Strelley crystal of 133 grammes weight and specific gravity of 7-60 is illustrated by photographs (Plate V, Figs. 1 and 2). Goniometric measurement and projection showed that the face planes developed belong to the forms a, {100}; n, {230} and p, a, Arsen ’ of a holosymmetric tetragonal crystal. The apparent absence of symmetry is due to extension parallel to the edge between adjacent pyramids, 7.e. elongation ‘au a and twinning on 103) a For many years this twin masked the identity of tapiolites in which it occurred ; such crystals were called skogbolite, and listed with orthorhombic species. Actually, distortion resulting from the elongation eat a combined with the ‘‘Skogbole”’ twin is a characteristic feature of tapiolite, columbian and other rutiles. A direct comparison may be made between the crystal (Plate V, Fig. 2) and the stereographic projection of it on a plane normal to the twin and com- position plane (Text-fig. 1). The 230 form is partly suppressed, but the orthorhombic disposition of the other face poles is obvious. Crystal angle measurements made with a contact goniometer were within a degree of the following recorded values (Simpson, 1917). 010*230 33° 414’ 100*111 61° 30! NGitp leleles del ye Gia fisetis ee 1007100 65° 46’ 100*010 90° 00° 198 F. M. QUODLING. The conventional phi and rho angle table for forms present is ° e a. 100 90° 00’ 90° 00’ n. 230 33° 414" =90° 00" fa ee deine Dos eae. 1aeod 42° 26 (Porter et al., 1951). Double indexing of the zone axis, the twin plane and the form p will be noted. Nordenskidld chose p, the prevalent hkl form, as a parametral plane and derived an a: c¢ ratio, 1 : 0-6464, very close to the ratio for rutile, which is cance aman sg, —_—~ ene, ae =. 1: 0-644. Both crystals are dihexagonal dipyramidal, 4/m 2/m 2/m, and may show the same form development with almost identical interfacial angles, and the asymmetric elongation and twinning. The structure of rutile was determined by Vegard (1916), and later by Huggins (1926). The data are, Space Group P 4/mnm; a, 4:58, c, 2:95; My: Co=1:0-°644; cell contents, Ti,O,. Goldschmidt (1926) made a structure determination of ‘‘ mossite ”’ from near Moss, Norway. This was a tapiolite in which the proportions of Ta,O, and Cb,O, by weight were approximately 52% and 31% respectively. The name mossite is reserved for crystals with a Cb,O, content exceeding that of Ta,O,; (Palache et al., 1944). The space group is P 4/mnm; cell dimensions a, 4-711, Cy, 9°12; cell contents Fe, (TaCb),0,. and the a,:¢) ratio 1:1-936, i.e. 1:0°645x3. The unit cell may be considered as a vertical stack of three rutile cells, a unit which suggests the name tri-rutile for this tapiolite structure. The metal positions are identical for rutile and tapiolite; the geometrical distribution of Fe and (Ta, Cb) on titanium sites is the ordered arrangement shown in Text-fig. 2. The tri-rutile structure requires a parametral plane with angle constants, phi 45°, rho ca. 69° 58’, and new miller indices for forms other than planes in zone [001]. The transformation formula from Nordenskiéld to Goldschmidt being 100/010/003. The pyramid {113} is very prominent on tapiolite crystals, almost invariably present, and may even occur as a closed form, but the parametral plane is never developed. This anomaly prompted the investigation of the tapiolite structure. Journal Royal Society of N.S.W., Vol. XCI, 1957, Plate V Big. 2: Twinned tapiolite from Strelley, Pilbara District, Western Australia. TAPIOLITE AND THE TRI-RUTILE STRUCTURE. 199 Powder photographs were made of rutile, striiverite and three tapiolites. The rutile was an acicular, wine-brown crystal from Hartford Co., Maryland, and the striiverite, tantalian rutile from the province of Tangafeno, Madagascar (Harvard Geological Museum specimen No. 80080). This material included a good equant 4 em. crystal of striiverite showing the forms a, {100} and p, {111} and the distortion which is present in the Strelley crystal. The tapiolites chosen were from the following localities: Skogbole, Finland (Museum of Natural History, New York, Specimen No. 14488) ; Tabba Tabba Creek, Pilbara district, Western Australia (Museum of Natural History, New York, Specimen No. 24491), and Strelley, Western Australia, portion of the crystal described in this paper. Photographs were made with the Straumanis technique on a camera of radius 5-73 em., using nickel-filtered CuK« radiation. Intensities were estimated @ Fe O TaCb Text-fig. 2. visually. Lattice plane spacings have been indexed and are listed in Table I, which includes published X-ray data for a striiverite, three tapiolites and the tri-rutile substances, ordofiezite, ZnSb,O,, artificial ZnSb,O, and bystrémerite, MgSb,0,, all of which had been investigated with copper radiation, except the striiverite of column 3, for which iron had been used. Powder photographs of the striiverite and tapiolites were made from heat- treated specimens as well as from the natural mineral. Material was heated in evacuated silica tubes for one hour at 1200° C., and then cooled slowly to room temperature. When half-millimetre spheres were being prepared, it was noticed that heat-treated tapiolite powder was russet brown in colour, while the original powder was nearly black. Striiverite was unaffected by the heat treatment, and the two films of its powder were identical. All specimens for powder photo- graphy were tested for radioactivity by Dr. Day of the Department of Geology and Geophysics, University of Sydney ; none was detected. The powder patterns of rutile, striiverite and tapiolite resemble each other closely. If attention is fixed on the more prominent arcs in the low angle region of the films, lateral shift will be observed before the Bragg angle reaches 45°. The shift indicates an expansion of the lattice of rutile to accommodate larger ions. The table of d spacings lists miller indices for rutile and tri-rutile in columns 1 and 14 respectively. The d,,) spacing shows an increase from 3-23 A. in rutile through 3-27 A. in striiverite to 3-33 A. in tapiolite. dy), which for tutile is 2-28 A., for striiverite becomes 2-31 A., and for tapiolite 2-36 A., correlating with a reduction in scale of the powder patterns. Actually the larger spacings such as d,,) are not sufficiently reliable for detailed study on 200 TABLE I. Comparative Table of Lattice Plane Spacings in Rutile, Striiverite, Ordonezite, ZnSb,0.4, Bystrémerite and Tapiolite. New Powder Data are marked with an asterisk. micro- ilmenite. In column 14, M d material. In column 1, I observed in heat-treate medium; w=weak; H= plane not indexed ; v.st.=very strong; m NI= columbite phase. C= Abbreviations : lite 14 13 F. M. QUODLING. *90199VT OTINY-ML 24Y Akl. 100 101 C? 110 C? elpeaysny “MA ‘AaT[AIS (Aoupdg ‘tug ‘sorsAydoay pue ‘Joon “ydeq Zarv) ‘ayordey, 4°65 4:19 3°38 2°96 12 ‘elpeaysNy “MA ‘“VqqeL eqqey, (HIOK MON ‘X10}SIH, “YEN Whosnjy I6FFS ON) ‘oyordey, 5°83 te} 11 “purlulg ‘eoqsoys (xIOA MON ‘AIOJSIE “VN UlNasnyl SSFFI ON) ‘oyfordey, 10 100 vvw 5 10 (paxeput ON) “purlule ‘9foqsoxg (Xopuy “WE'S'V) ‘eytordey, 3°67 40 (‘GG6T ‘281 “d ‘E-T ‘84 “IOA ‘aouvi gy “Ui “90S “77Ng7) (‘pexepul yoN) “oypordey, (99 ‘d ‘OF “IOA “SG6L “UT “wP) “g0UeI ‘oqnopayuryg ‘oyjordey, 3°34 (99 “d ‘OF “IOA ‘Gc6L “WU “MF) °O*4S3W “OPLIOULOT4sSA 3°32 100 (99 ‘d ‘OF “OA “GS6T “wy wr) “(ePyyIV) °O*ASUz 3-30 v.st. : (99 *d ‘OF ‘IOA Sc6l “wy “wy) *O*4SUz “aytzouop1O 4:58 10 4-i1 20 3:26 90 ‘Ieosesepepl ‘Ouayesuoy, “(UInesny, preaAIe yy 08008 ON) e}eanays d.* 3:27 100 (‘pexopul 4ON) ‘saqeyg AvleyL poyelopa, ‘yereg unyUeqes JOATY *(xepul "W'L'S'V) e#eandys 3:87NI 20 3-59NI 40 3°25 2:76 80 40 ‘VWs “CW ‘pIOsHeH “OANA its dee 3-28 90 Caomert emma) tv | = 110 TABLE I.—Continued. Comparative Table of Lattice Plane Spacings in Rutile, Striiverite, Ordonezite, ZnSb,0., Bystrémerite and Tapiolite. Continued. TAPIOLITE AND THE TRI-RUTILE STRUCTURE. 201 x | ‘CONST MTEL AY S| SY S Si aes aN = = 4 =) a a oaa nN a a a nN * “errerysny “MM ‘Aas | *. 2 C=} oO ee} ° © a ~ é Onl CSCUPAS TAM M SOSA COs NpUBlNorlls =) acre ye Sa es ‘Joan “doy ZSLW) -aqordey, Nn a Nn nN N nN ial ct . oO Oo So i=) te) wD nN ie) i=) = ec a ba ) Lon = SMITE SUYE WA CUCU, COOeT ei ito tes) Sti ee yi aay aa a (yIOK MON | co © 19 oF a tol —) a oa) a ~ q ‘AIOYSIT “YEN UNOS a n a a a a 4 ri 4 4 T6FPS ON) ‘oppordeL| . nS er IC SO as ar oS Lal Lon [o>) ite} | Lon nN ae S “‘puvpury ‘afoqsoys | « ron Ce) ey ° tS oo RB “ = (yIOX MON | od © re} or) a cl °o a oe) = ay ‘AIOISIT “YEN UUNasny][ a a a a a a or = 4 | S8PFI ON) “owordey| . wo of 6 ims we ma ° = lor) 7 re iS | (‘poxopul JON) | _- i Ce) 4 x © re) S “purpuny ‘eoqsoys | > ee See tar MOL as A ee ° (‘xepuy ‘W'L'S'V) ‘ayorde yy, i> | i> Nn N rc ce cr ibe “4 =) S (—) i) f=) —) f=) Lal isa) © N N o nN S GSC AST OS oP Oe OA Illy Po 1s a ae oe SS = o ‘cums mp og ang)|F| = — 2 A we =~ (pexepUur YON) “oyToLdeL, ae) Bi ea | fala ee ee Ki z > a Bs > B a ry (99 “d ‘OF “IOA ‘GG6I “UT “wP) | d z 8 % a 3 = ‘gouvig ‘aqnojayueyy “aytfordeg, a a aoa a =I . oO So So o Oo So lal coal ive) ie) N coal o et COOR GROTON em oats no cota eren | uy ec 6 ‘sc6l “wy wy) *o'agaw || - ~ & 2 fF © 5 “gjaWOI}SAG, a a a a a a ci (=) So (= i=) o o a = oo lor) wo nN oO oO GOON st se col Mat eou gic B ag -) ‘OF “IOA “SG6T “wy wr) R : é “(epyAV) *O*qSuz Shi ora eee foe = he ri Bec ee) eee a > (99 ‘d ‘OF “OA a 1 12 Saal oO S a =} nN 6 ‘ec6t “uy my) *o'aguz;|T| < -— 2 SB SC © ° < “9}IZIUOPIO N i> | i>] N Nn i> | rc ec : o So So o o So o i=) Lael So | is) J [o> | nN NX rc 2 “reosesepeyy ‘ouesesuoy, | *- S baal S © 2 S * ‘“(umasny, prvarey | 7 < a a x is ei | 08008 “ON) o}eANIYS : = =) 5 S a = — ~ 7 bP) ct a eS *soqejg Ave, poyesiopagy | d a Go x = oo S ‘yejeg unjueges IAT i al) a cs = = | “(Xopuy “WLS V) eyeandys | f—) ° ° ro) °o [—) | ~ as ~ Nn 7 Ss * LSet ioe) ~ bs} ic,9) ‘vWsal|sd gh SE teh ee va SS “CW ‘ployee ‘apy a aaa a : So. Joi. to ko ° io] o I ~ I So Lond é 3 ~~ ian) f=) cr o — rc a (aongel enna) “1y | = | BS) Gas Fe 202 TABLE I.—Continued. Comparative Table of Lattice Plane Spacings in Rutile, Striiverite, Ordonezite, ZnSb,06, Bystrémerite and Tapiolite—Continued. F. M. QUODLING. = comeromment mi|3/2 8 £ 8 8 gS 8 sees a gz sia a a nN S oD ar) Sa) a 3 oa ee} re} jen eet ‘elyerysny “M ‘AoTTorys | *. | S io > oD ° a 3 rs =) oc) (‘Aoupsg “tug ‘soisdydoay pue| 7} 2 RC oS aes aa oo} 2 ‘Joo “ydeq Zer'y) “oqordey, ote Te A eG ie Weeden nae a Tt ba Siiheoe = 35 Se cl, ee eee So “eyTRIISNY “MA “eqqe eaqqee qt 0] | Si (HIOK Man |G F Ss $ 8&6 8 8 & & Es S tal ‘AI01STH, “RN Wesnyy = = a a = = & a = 4 | T6FFS ON) “OWNOIGWL| .| 6.6 © ww 60 © © © o ° _— ite} Nn [to} hol o te} “puryurg ‘ajoqsoyg = ze eo} a (YIOK MON = S 3S 3 3 oy 4 $s & van ‘AIOISTH, “YEN UMesnyy = = a =] = 4 = = | SSFFT ON) ‘opyorder; . ro) A) MOmMOt one ° _ ire) nN x o oO Soe | (‘paxeput JON) | _- a © + =) ° 4 = = “purypurg ‘a]oqs0¥s | = | es yD We ae Se aS. 2 | (xepul “WL'S'V) ‘epordey, ay "ae esis): | eee t | | i=) So i=) iS o oO S _ o * * o ~ ~ Nn 1 com @ oS ie} S (Sc61 “ZeT “d ‘e-T ‘82 “I0A| _; 2 Beg) Se INS S 3g ° ‘auDig “Up “90S “N_) 5 5 3 3 : x ‘ (‘pexepul 4ON) ‘aztordey, ms or LAPD. bee E a 7 ei ua z =| a > ua a 4 ive) oO So for) x | (99 °4 ‘OF TOA ‘Ceol “my “wP) | © mS oo ‘gouelg ‘aqnojajyueyy “eypordey, 4 4 4 4 e o =] i=) i=) _ ~ oo o ite} (99 ‘d ‘OF ‘IOA| _; 3 se iS ‘coeL “MT “Mr) *O*aS3IN 2 ° ages “aplIoMloIysA ge . So So So Lal 7 N 7 Pa ert et toas SAS acy oe 8s 3 B © ‘OF “IOA ‘ “wy “ue ; : : < ; : i “(eroyryTy) *O*asuz "it Eahs SFi. + Fae r x . = _ Ea = ~_ ~ ~_ ~_ | = > a > - a n n n (99 ‘d ‘OF “IOA] _. | cS a & ee = 12 ‘Cc6L “MAT “MP) *OFQSUZ | : : : es Ss “aq 1zou0psO, | 7 ted i . So So i=) oS So _ re} oO re} o x wo ‘eosesepey ‘ouayesuoy, | *, = a oS = fe * “(uMasny, prvarey | > is ees Si s 08008 “ON) e310ATI}S | | Se ees Ps = Lal =~ nN oD te} oO (‘poxepul JON) | | ~ Sy Ge tS bt ° ‘saqeyg Av[e peyerepag | d o ve) ~* ~~ o oe) oe ‘qe[eg UNUegag JOA et Set 4 =) (xopul “WiL'S'V) esean7S | 2 21S 8e 2 2 e a ~ ro) 8 g So . Or + co ~*~ ~*~ o oo o ms visa} a ; DG “CW ‘prioyyeH “oN 4 a ow 4 a rw Sikes 2 8 2 eae 7 So a o = nN - | Caoyel emmy) “YS g os sg Ss 4 os | TABLE I.—Cgqntinued. Comparative Table of Lattice Plane Spacings in Rutile, Striiverite, Ordoftezite, ZnSb,0., Bystrémerite and Tapiolite—Continued. TAPIOLITE AND THE TRI-RUTILE STRUCTURE. ; ea} Bs OUT ONAL “HY : S x Se a a 8 N on sr) bo) Nn N oD . re elperysny “M ‘AaToIy4¢ | *. = x EA pes 8 3 oc) (-Aoupdg ‘tug ‘sosdydoay pur} >| % : 2 Te Ge PG ‘oon “ydoq Zer'v) ‘owfordey, cs ae eee mm hast) om . oS o oS o So oO Lama N wa N * oO N ea) ‘eneaysny “mM “eqary eqqet|s | S & 2 2 S 2 a (3IOK MON | a a o teal 4 4 4 4 ‘KI0ISIT “YEN UNasnyy a = n 4 4 q 4 | I6FFS ON) ‘oqtordey,| a.) Ho © o © eo | Lal oO oO N on * N eal “purpurgt ‘ajoqsoyg | * | 32 Seance eA ee — (YIOK MON | a a ion inl a = q ‘A104SIFT “VVN WINESN], a 4 = 4 4 4 S8FFL ON) “oporder| ° oF CS a) _ na wo nN on oO N Sant (‘paxepul JON) | _; ea a a mH a S ‘puryung ‘aoqsoys | 7] es ° 3 . . (a) d Cxepul “WL's'v) 9 ‘eqordey, | S a SS = S _ ~ o bo) i) ~ ~ for] oO o oO CoG ZSE ca S=h “SZ 10A | | & Ss Ss SS oO Qounig “wy ‘vog “yng)| >| @ See = a (pexepul jON) ‘oaqtordey, a Sp 3 | mS a | | 2 FS | | a d (‘99 “d ‘OF ‘TOA ‘SC6T “UT sa cs a ‘gourig ‘aqnojayuvyg ‘oyordey, 4 4 . So So Lal on wo (99 ‘d ‘OF “TOA fee = é ‘cor “uy “wy) *orqsay | >| ay “ayIOMIOIySA und vad So So 4 Lan ise) (99 -d | (oe) peal a © ‘OP OA ‘scot “uy mp)) >| SS Ss “(epyyiy) °OFqsuz ee Ly 4 | a (99 “d ‘OF “IOA] | ee me = 6 ‘ecol “uy wy) *orqguz);S) BS a *ay1ZOUOPIO ee 7 e i=) f=) S Lael inc) et o “Ieosesepreyy ‘ouasesuoy, | *. ‘8 =) 3 = 3 ST “(amMesny, preAiey | > i! ; ie! v2 ; 08008 ON) e3!70ATNI4g ie femelle in y . o So So So So Ln Nn bs) wo * oo (‘pexopul 4ON) Pe ‘sayeyg Avpep paywsapag|d| = le = = Ss ‘yeeg unjueqag JOA = a = a *(xopuy “W'L'S"V) eyeanyg | ° i) =] ° ° La ~ ~ o ~ o * ~ (o>) ~ x or) fo) wo a Wsnjd] a ial hele ae S “QW ‘prioyqyey, “OTN = = = wi = a 4 | . iad o So So o _ oO nN x i> x . ay a a = =) r=) a f—) | (9014487 eTgny) = “27y s S nt g Sg mi UN 99 203 204 TABLE I.—Continued. Comparative Table of Lattice Plane Spacings in Rutile, Striiverite, Ordonezite, ZnSb,0., Bystrémerite and Tapiolite. Continued. 14 F. M. QUODLING. OOIeT OINY-ML 244 hkl. 413 316 420 109 119 406 13 “eleaysny “MA ‘AoTatys (‘AoupdAg ‘tug ‘soisAydooy pue ‘oon ydeq sstv) ‘eyordey d.* 1-078 30 1:073H 30 1-061 20 1-034H 1:000H 10 0:978H 0-963 0-942 20 12 “eyeajsny “MM “eqqey eqqeL CYIOA MON ‘AIOJSIHE “YEN Unesnyy T6FFS ON) ‘oqpordeL, * 1-077 40 1-073 50 1-061 30 1-034 1-001 40 0-963 0-941 20 11 “purpuly ‘ejoqsoys CxIOK MON AIOWSIAL “YN UNosnyL S8FFI ON) ‘ozrfordeyy, de 1:078 40 1:072H 50 1-061 20 1:033H 1:001H 30 0-963 0-941 20 10 (‘pexepur 4ON) “purluly ‘efoqsoug CXopur “WES Vv) ‘oordey, 1:08 1:06 40 1:01 (9961 ‘281 “d “E-T ‘82 “IOA ‘soul “UT “908 “NT) (poxepul JON) “oqTordey, 1-073 1-063 1-035 1-001 0:965NI Vw 0-950 Vw 0-946 0-940 st (99 “d ‘OF 1OA “SG6L “uy “wPr) ‘gourd ‘eqnopyueyg “ayrpordey, (99 “d ‘OF “TOA zi ‘GG6L “MW “wH) "O43 “OPIIOMIOIJSA (99 “d ‘OF “IOA ‘GG6L “ur “wr) “(ePpyIV) °O*asuz (99 “d ‘OF TOA ‘Cc6L “uy “W) °O°ASUZ, “ay1ZaUOPIO “Ivosesepeyy ‘ouasesuOT, “(HInesnyY PIvVAIE_L 08008 “ON) 2}1eANI4S d;* 1:055 30 1-048 1-036 0-977 10 0-918 20 (‘poxopul JON) ‘soyeyg Ave poyesepad ‘yeeg ungueqog JeATYy “(xopul “WLS V) 2712A0I48 1:04 d* wea “CW ‘PloyweH “ONY 1-042 1-034 0-942 Ce0nIeT eTNY) “7714 Akl. a eee ee eee pes ae lq, ae eae has ae 0-905 20 402 TAPIOLITE AND THE TRI-RUTILE STRUCTURE. TABLE I.—Continued. Comparative Table of Lattice Plane Spacings in Rutile, Striiverite, Ordonezite, ZnSb,0.4, Bystrémerite and Tapiolite—Continued. 5 jac ften| x ‘ONT MUL MS] 2 2 Sf A BRS & S A SG ve) i> | N ive} 10 = on * of Lie} ~ + tS] ve} re a ive) co lo} i=) fo a) ‘epensny ‘mM ‘Aopong|*.| 2 a & = S$ S$ & S&S F&F & act (‘Aoupsg ‘Tug ‘soiskydoaxy pur | > 2 a 3 S = o 2 Se og "oon “ydod Zel'y) ‘oqfordey, eel Ce sean gia eg fee ee : Of RON Gon cy Move al hoy o Noo VS = i> | N ine) bo) oO oO ve} * Ll “erpesysny “MA “eqqeg, eqqey, | « Tl Les Fi H Micorieng io tet a oS a (yIOX MON | od ror) a a & S 3 oS Ea wo BS q ‘S10}SIH “YEN WNasnyy OL sicmboW Momo Ton Foun of fo «Oo T6FFS ON) ‘opordey| . i) r= ° 19 ° ° =) =) =) —) _ N rc ba) Ad ise) oD of © N “purpury ‘ajoqsoyg | « ies a ioe an SA ce, a = (yox MeNIG| & & 8 & B&B & & B BS & = ‘AI0ISIT “YUN UUs] ORC ESO MOU lO NOs o. Hol SSFFI ON) “oyordey | |. =) =) ° a ° =) ° rc) =) ° Loe N cr to) ~~ * oO N ive) nN (‘poxoput oN) | S; ‘purlunt ‘efoqsoxys | > (xepul “WiL'Ss'V) ‘oyordey, iol Cecor ‘zer -d ‘et ‘ez toal_,| 8 & = 8 8 § 8 $$ sounug “up ‘vos “yng)|2| 2 GC @ ® ® © 6 O© (paxepur yoN) ‘azole, rs eh ad en oo Sk Hi a a7 FE 2 =| = =| = (99 “d ‘OF “IOA ‘SG6T “MW “wF) | “q0uvIT ‘aqnopayueyO “aypordey, i (99 “4 ‘OF ‘10A |; “GG6L “WM “wP) °O*AS5 ‘ayoulorysAg, “| Pe ee ‘OP IOA ‘SS6L “wm “wr) “(epgysry) °O*qsuz 4 i ; (99 “d ‘OF ‘IOA eS SS6L “UL “MP) °O*GSUZ “9y1ZOUOPIO Ki “reosesepeyy, ‘Oueyesuoy, | a | 8 S 2 3 S & “(unasnyy prvarey | > 2 Me ey BGs oe 08008 “ON) e}140AnI}S | 7 S 2 ee ce Naa? : ° ° ° Of Rou Lal oD oO i>] Nn of 7 (paxepur 40N) ‘saqeyg AvpepL poyerepayt | ‘yereg unqueqeg JaaTy “(xopuy “WLS V) eyeandys |, | Lal * S Fa ee Tecate Cah ote eo veald| 2 a eo © © ® & & “QW ‘piosqiaeH “oTtyn i) co) ro) —) —) rn) ro) ° . t=} So So i=) o So i=) ie 2) —_ N + oO oO NX NX = : ae Comet omny) my} S| s m ass § $ & ¢ 06 TABLE I.—Continued. Comparative Table of Lattice Plane Spacings in Rutile, Striiverite, Ordoiiezite, ZnSb,0., Bystrémerite and Tapiolite. Continued. F. M. QUODLING. 90144VT OTNY-W DL 244 hkl. 530 443 443H 329 516 516H 525 “elyerysny “MM ‘AoT[ary9 (AoupAg ‘tug ‘soisAydoay pue ood “ydeq sary) ‘eqfordey 0-815 20 0-809 40 0:808H 50 0-803H 0-798 40 0-797H 50 0-793 “eyeaSNW “M “eqqey eqqey, (yIOK MON ‘AI0ISIFE “GUN WmMosnyy T6FFS ON) “oqpordey, 0-815 30 0-810 0-809H 50 0-8038H 10 0-798 50 0-797H 50 0-793 10 30 “puepurg “afoqsoyg CxIOX MON ‘AIOJSIT “YUN UNosn yl 88FFI ON) ‘aqordey, d.* 0°816 20 0-811 20 0°810H 0:°803H 0-799 30 0:797 60 0-793 10 10 (‘paxepul JON) “purus ‘aoqsoyg Cxepul “WiE's'V) ‘ayordey, (GG6T ‘28T “d ‘E-T ‘82 “IOA ‘auDLy “Ure “90S “71Ng_) (‘pexapul JON) ‘aqordey, 0-815 0-809 0-797 0-795 (99 “d ‘OF “IOA ‘GC6T “UT “wP) “g0uvIg ‘aqnojayueyg ‘aypordey, (99 “d ‘OF “OA ‘GG6L “WW “Mr) °O*QS3N ayloMorysA ge 9 “d ‘OF TOA “CC6T “UW “wPy) “(eloyysy) *O'qsuz (99 “d “OF “IOA ‘ocel “WW “MF) °O*QSUz "a}Z9UOPIO “Ieosesepeyy ‘ouayesuoy, “(UMesnY, PIVAIV]L 08008 “ON) eeAnNI4S d.* 0-797 10 0:791 30 (‘poxapul ON) “saqeyg Ave poyesopay ‘yeleg ungueqeg IOAIy *(xopuy “WLS ¥) e9AnI4g ‘Ws “CW ‘ployyeH “ONY (90144e'T 9Tgny) = "74Y hkl. 530 323 TAPIOLITE AND THE TRI-RUTILE STRUCTURE. 207 account of the rapid variation in d values with slight changes in small glancing angles. Planes of the tri-rutile structure where 1—0 or 3n, where n is an integer, are common to both lattices and produce the distinctive lines of the powder patterns ; in other words, the rutile lattice is dominant. All okl reflections are restricted by the space group to those with k-+l—2n. Extremely feeble but significant arcs appear on powder photographs of tapiolites. They may be better developed in one tapiolite than another, and are most distinct in films of heat-treated specimens. When indexed, they prove the existence of a tri-rutile structure. The planes are: 101, 112, 202, 211, 114, 105, 204, 222, 312, 215, 314 and 525. Powder films of heat-treated specimens, in addition to giving evidence of the tri-rutile structure, prove that marked contraction takes place in the ec axis length on heat treatment, apparently a steric effect of geometrical packing. Extraneous lines in tapiolite patterns probably belong to a columbite phase and to microlite. These arcs are identified by the C and M respectively, in column 14. Columbite, the orthorhombic paramorph of tapiolite, is frequently intergrown with, and associated with, tapiolite (Meizner, 1951; Permingeat, 1955). Microlite is recognized as an alteration product of tapiolite. The formula may be written A,B,O, with A=Na, Ca, K, Mg, Fe?, Mn?, Sn’, Pb?-++rare earths. B=Cb, Ta, Ti, Sn?, Fe’, W? (Palache et al., 1944), which indicates that the structure tolerates a great deal of replacement. Rosén and Westgren (1938) showed that there was close resemblance between microlite and a roméite- atapite group of minerals which had been studied by Machatschki (1930). Spacings calculated for faint extraneous lines in the tapiolite photographs correspond to those giving the most intense reflections of the roméite pattern. It is not suggested that the antimony compound is present, but rather some related tantalian substance. Recently compounds of the general formula A,B,0, have been examined (Gasperin, 1955); they included Sn,Ta,O,, Pb.Sb,0, and Ca,Ta,O, and were placed in the koppite-type series of oxides of the pyrochlore-microlite group. Very weak lines in the striiverite photographs which cannot be indexed are possibly due to ilmenite, an exsolution product of some rutiles, such lines are indicated in column 1 of the table by the letter I. The formula for stritverite is Fe,(TaCb).Tig_3x)0., where the maximum value for x is 0:2 (Palache et al., 1948). For the value x=0-2 the formula may be written Fe?(TaCb),0,2TiO, ; one part tapiolite and two parts rutile. Striiverite may be indexed as rutile, i.e. there is statistical distribution of Fe?, Ta, Cb and Ti on the metal sites of a rutile lattice which expands to accommodate the larger ions. Cell dimensions determined for rutile are a, 4-584, c, 2-94, and for striiverite a, 4-63, c, 2-999. Discussion of the Tri-rutile Structure. Striiverite, with a mono-rutile structure, is in part tapiolite in composition. Morphologically the minerals may be identical. Study of chemical analyses shows there is departure from theoretical composition and strict stoichiometric proportions in both. The question arises as to whether the tri-rutile structure is essential in tapiolite or whether a disordered state may be natural. Interesting information on this point has been gained by reference to other researches. The tri-rutile structure has been determined for artificial ZnSb,O, (Bystrom et al., 1942), bystrémerite, MgSb,O, (Mason et al., 1952) and oidofezite, ZnSb,O, (Switzer et al., 1955). In bystrémerite the superlattice lines are relatively strong. The mineral has not been found crystallized, so whether the well-developed superlattice 208 F. M. QUODLING. has any effect on morphology is not known. Ordonezite, however, occurs as simple crystals in which three forms only are developed: {001}, {110} and {011}. The {011} has a rho value ca. 63°, which directs attention to the long ¢ of tri-rutile. So far as the author is aware no tapiolites have been described in which this okl form is the only pyramid present. When Bystrom, Hok and Mason (1942) published X-ray data on the tri-rutile structure of ZnSb,O, they gave lattice constants for the isostructural substances MgTa,O,, CoTa,O, and NiTa,O, also. During experiments a ‘‘ mono-rutile’’ was produced when MnSb,O,7H,O was heated for four hours at 800° C., and a chromium antimony oxide also appeared to be ‘* mono-rutile ”’, but the X-ray photographs were not regarded as entirely satisfactory. Brandt (1944) carried out research on ABO, compounds: Cr, Fe and Rb columbates, Al, Cr, Fe, Rb antimonates and Cu, Fe and Rh tantalates. All were found to have mono-rutile structures. Cell dimensions determined for the iron tantalate were a, 4:672; c, 3-042, very similar to rutile. The other iso- structural substances had parameters close to these values. No _ tri-rutile structures were found, but when iron antimonate was being prepared a tri-rutile, FeSb,0,, appeared when oxides were heated for one day at 1130° C. Hutchison (1955), in a report on optical studies of tantalum minerals, stated that X-ray precession photographs of tapiolite from Ross Lake, N.W. Territory, Canada, showed that the mineral had a rutile structure, not a tri-rutile one. No X-ray data were given in this paper. It would seem from experimental and other evidence that tapiolite may or may not show a superlattice structure. The opinion is expressed that natural crystals are at first mono-rutile, with statistical distribution of ions of different valence over the metal sites, if necessary with lattice defects, and that this structure may persist indefinitely, or be replaced after a time in part of the crystal mosaic by the ordered tri-rutile ion assemblage. ACKNOWLEDGEMENTS. For material given for X-ray analysis and information supplied, I should like to thank Dr. G. Claringbull, British Museum of Natural History, London ; Professor C. Frondel, Harvard University ; and Mr. D. Seeman, of the Museum of Natural History, New York; and for assistance with powder photography, Professor O. C. Hutton. I am also indebted to the Council of the University of Stanford, California, for the privilege of association with its Department of Mineral Sciences during part of a sabbatical leave. REFERENCES. Brandt, K., 1944. Arkiv. for Kemi., Min. Geol., Band 17A, No. 15. Bystrom, A., Hok, B., and Mason, B., 1942. Arkiv. for Kemi., Min. Geol., Band 15B, No. 4, 1. von Gaertner, H. R., 1930. Neues. Jahrbuch fiir Mineral., Abt. A, Beil.-Band 61, 1. Gasperin, M., 1955. Comptes Rendus, 240, No. 24, 2340. Goldschmidt, V. M., 1926. Sprif. Noiske, Videnakaps. Oslo. 1. Mat. Natur. Klasse, N.1, 106. Huggins, M., 1926. Phys. Rev., 27, 638. Hutchison, R. W., 1955. =Am. Mineral, 40, 432. Johnson and Weyl, 1949. J. Am. Cer. Soc., 32, 398. Mason, B., and Vitaliano, C. J., 1952. Am. Mineral, 37, 53. . Machatschki, F., 1930. Zezt. fur Krist., 73, 159. Meizner, H., 1951. Newes Jahrb. Min., Monatschefte, 204. Palache, C., Berman, H., and Frondel, C., 1944. Dana’s “‘ System of Mineralogy ’’, Vol. 1. Permingeat, F., 1955. Bull. Soc. Min., France, 78, No. 1-3, 137. Porter, M. W., and Spiller, R. C., 1951. The Barker Index. Quensel, P., 1941. Geol. Foren. Forhandl., Stockholm, 63, 295. Rosen, O., and Westgren, A., 1938. Geol. Foren. Forhandl., Bd. 60, H2. Simpson, E. 8., 1917. Min. Mag., 18, 107. Switzer, G., and Foshag, W. F., 1955. Am. Mineral, 40, 64. Vegard, 1916. Phil. Mag., 32, 65. THE MANILLA SYNCLINE AND ASSOCIATED FAULTS ALAN H. VoIseEy, D.Sc. With Plate VI. Manuscript received, November 19, 1957. Read, December 4, 1957. ABSTRACT. The Manilla Syncline and Namoi Fault are recognized and described, together with many faults, some causing schuppen-structure in the western portion of the Hunter- Bowen Orogenic Belt in north-eastern N.S.W. The Baldwin Formation and the Barraba Mudstone are regarded as constituting the Manilla Group of sedimentary rocks. The Manilla Syncline is a dominant structural feature recognizable for some fifteen miles to the north of Manilla, New South Wales. In his comprehensive description of the geology of the Western Slopes Benson (1917a, p. 250) mentioned that there was a synclinal structure in this vicinity, but did not emphasize its importance. The writer feels that it warrants special attention in view of its position in the tectonic pattern now emerging from more detailed study of the Upper Paleozoic orogenic movements in north-eastern New South Wales. This paper deals also with the structures in the rocks of Benson’s Near Western and Middle Western zones, and the map (Plate VI) includes parts of the Eastern Zone and the Serpentine Line. The area shown was mapped in the field, use being made of aerial photographs supplied by the Department of Lands, N.S.W. STRATIGRAPHY. Names used with reference to rock units in the following discussion are substantially those of Benson (1912, 1913a), but in order to conform with the Australian Code of Stratigraphic Nomenclature (Raggatt, 1956), and in anticipation of work soon to be published, some slight modifications have been made. The pre-Devonian rocks east of the Serpentine Line, called Woolomin Series by Benson (1912, p. 100), will be referred to as the Woolomin Group (Spry, 1953, p. 129). The Lower to Middle Devonian radiolarian claystones, cherts, limestones, tuffs and breccias, which were called the Tamworth Series by Benson (1913a, p. 495), will be designated the Tamworth Group. They include the Moore Creek Limestone (Benson, 1915, p. 541) and the Tamworth Common Cherts, the last-named being generally referred to as the Tamworth Cherts and thus shown on the map (Plate VI). The Barraba Mudstone and underlying Baldwin Formation, regarded as Upper Devonian, constitute the Manilla Group. This departure from the inclusion of both Baldwin and Barraba sediments in the Barraba Series (Benson, 1915, p. 577) is made because the most satisfactory mappable boundary in the Manilla-Bingara belt is that between these two formations. Their upper and lower limits are by no means as easily recognized. As Benson’s names are so well established for the particular portions of the sequence they have been retained. 210 ALAN H. VOISEY The term ‘‘ formation ” is preferred to ‘‘ agglomerate ” for the Baldwin portion because it consists of a number of different kinds of rock. The so-called ‘*‘ agglomerate ”? grades into breccias and finer-grained sediments, which Benson called tuffs, but which would now be better described as greywackes in the sense of Pettijohn (1957). The degree to which they have been derived from volcanic material has yet to be determined. Attempts were made to measure stratigraphical sections through the sequence at various places but the extensive faulting has rendered it virtually impossible to obtain reliable figures. The thickness of three thousand feet for the Baldwin Formation estimated by Benson (1913a, p. 495) seems to be a reasonable one. Two thousand one hundred feet were measured by the writer by means of a traverse made over Pyramid Hill. Of this about 10% could be described as breccia or ‘‘ agglomerate ”’, 30% as greywacke and 60% as mudstone. About two thousand feet of Barraba Mudstone overlying the Baldwin Formation are represented in the area mapped. There are a number of breccia and greywacke beds in the mudstone sequence, mainly in the higher parts of it, but the total percentages are much less than in the Baldwin Formation. Benson (1913a, p. 503) defined the Burindi Series and later mentioned the presence among Burindi mudstones of crinoidal limestones and conglomerates south of Crow Mountain. These beds and others exposed by Borah and Spring creeks are included in the Burindi Group, which will not be differentiated into Upper and Lower parts in this paper. STRUCTURAL GEOLOGY. The area shown on the map (Plate VI) was chosen to portray the Manilla Syneline, which had been an object of interest to the writer for a number of years because of the excellent physiographical expression arising through the contrasting resistances to erosion of the Baldwin Formation and the overlying Barraba Mudstone. It was extended to include the Serpentine Line and the Black Mountain Fault. For some twelve miles to the north-north-west of Manilla the railway and road to Barraba traverse the wide, relatively flat, valley of the Manilla River. This has been carved out of the soft Barraba Mudstone, which occupies the axial region of the fold. On both sides of the valley hills rise steeply, forming conspicuous cuestas. The effect is made more marked because of the sudden change from the mudstone to hard arenaceous material forming the topmost bed of the Baldwin Formation, from which it has been stripped by erosion. The syncline is best seen at its southern end from points along the Somerton- Manilla and the Tamworth-Manilla roads. Good views, looking south down the axis, may be had from the Barraba-Manilla Road north of Upper Manilla. The structure closes in the south but is destroyed at its northern end by thrusting from the east, as shown on the map (Plate VI) and by means of sections (text-figure 1). The Yarramanbully Anticline lying to the east of the Manilla Syncline is extensively fractured, the principal breaks being the Veness, Bowman and Lowry Faults. It pitches to the north, and the strata of the Tamworth Group appear in the central zone. It has not been thought necessary to name all the faults, but only the principal ones. Benson (1917a, p. 253) had previously discussed the Black Mountain and Baldwin faults and the Serpentine Line, which was later called the Peel Thrust (Carey and Browne, 1938, p. 605). To these may be added the Fleming, Namoi, Lowry, Bowman, Veness, Wilson and Borah faults. H SERPENTINE = LINE WESTERN ZONE +—NEAR ZONE THE MANILLA SYNCLINE AND ASSOCIATED FAULTS. 211 Zs = % a (a) <= “BEA aa) Zee 4 as oe oe Pe é CAs ult [ ol fe off ¥ NOT S Y) ay. Q Aw 3 Wy SG 3 : = & uu NS ut ca ¥ LE aag y 2h ~~ wn 5 N 2 > SG > GROUP WESTERN Text-fig. 1. OATUM IS IOOOFEET ABOVE SEA LEVEL LEGEND SHOWN ON MAP BUT ADD :- MOORE cRK LimMesTONE [ZW AND LOWER BEDS OF TAMWORTH MILES 2 212 ALAN H. VOISEY Greywacke bands in the Barraba Mudstone outcropping to the west of the Black Mountain Fault are folded into a south-pitching syncline. It is convenient to use Benson’s tectonic divisions in describing the structures. (i) The Eastern Zone. The strata of the Woolomin Group jaspers, cherts and phyllites lying to the east of the Serpentine Line are invariably tightly folded and shattered and have experienced slight dynamic metamorphism. They are extensively silicified and, at present, there is no consensus of opinion regarding their method of formation. (ii) The Serpentine Line. The Peel Thrust is not a single fracture but a complex system of faults, probably with a very large aggregate displacement. Some lateral as well as vertical movements are certainly involved. There is always a very well marked change in the rock types across this line. An interesting feature is the presence of slivers and lenses of rocks of different ages in the shattered zone. Serpentinite occupies a number of the fractures along the Line. No observations additional to those of Benson were made on the ultra- basic rock. (iii) The Near Western Zone. Benson (1917a, p. 238) took this zone as extending from the Serpentine Line to Pyramid Hill, but the writer prefers to take it as occupying the belt between the Line and the Namoi Fault. This is a very important fracture, which separates the steeply dipping, isoclinally folded beds from the more gently dipping ones in the Yarramanbully Anticline and the Manilla Syneline. The fault traverses the whole of the area mapped and was followed for several miles northward. It undoubtedly continues for a considerable distance to the south. A wedge of Burindi rocks lies adjacent to the Line all along the eastern portion of the area. Within the wedge there appears to be a broken syncline pitching to the north. Another major break, the Fleming Fault, separates these beds from the Manilla Group strata to the west. Except for an occasional westerly dip of 70° or more. the strata in the isoclinal zone are vertical or dip steeply to the east. Strike-faulting is probably more prevalent than could be shown on the map. Because of the lack of marker beds it was not possible to determine the extent of the repetition of the beds. It was difficult also to ascertain which portions of the belt were Baldwin and which were composed of Barraba beds. Benson (1917, Plate XIX) regarded most of them as belonging to the Barraba Mudstone, but the writer, because of his observation of so many greywacke beds, is inclined to think that the strata for the most part are the equivalents of those he has placed in the Baldwin Formation. (iv) The Middle Western Zone. This zone is taken to extend from the Namoi Fault to the Baldwin and Black Mountain Faults and includes the Manilla Syncline and Yarramanbully Anticline. The dips in this zone are generally below 30°, in contrast to those exceeding 60° in the Near Western Zone. This difference has had a marked effect upon the physiography, which is characterized by numerous well-developed cuestas wherever the Baldwin strata outcrop. Parallel lines of low hog-backs are typical of the Near Western Zone. On the aerial photographs these patterns are equally distinct, changing across the Namoi Fault from a series of parallel lines on the east to groups of zig-zags on the west. The Lowry, Bowman and Veness faults appear to be closely related to the Yarramanbully Anticline. This structure can be recognized by the changed dip directions of the beds. Benson (1917a, Plate XIX) showed much of the Parish of Veness as consisting of Tamworth strata. These seem to occupy much of the — re, 7 SCALE Y KR SN x w Q = NS G 2) w Y x Q = x } Wy . w) = wy x ~ = x = lu i RAILWAY ——— SERPENTINITE [HN Dn op aoam 3 Journal Royal Society of N.S.W., Vol. XCI, 1957, Plate VI } O/PS bweren vo Lwoen 30 MUDSTONE BALDWIN f FORMATION TAMWORTH CHERTS LEGEND SILURIAN ? ALLUVIUM PERMIAN WOOLOMIN GROUP | | 7REND LINES ——~— RECENT FAULTS coal ai Arte ys é Aw 7. YE. Ae vhs Aycutsisos fayntt i ies ya E fi A : 4 4 —_ i ile we " A wats ‘ 7 Pk Tai | J | irs He ose | ei “Mer ~~ WY) aA ree ( ha a, ee ee tt oe oleh am ¥i oa “ig ee ahi hi Cad ily meal a wb aid so Sear s AG Rina 7 iy tee» nf ey THE MANILLA SYNCLINE AND ASSOCIATED FAULTS. 213 low ground, but, as they could not be defined with certainty and separated in the field, they are not indicated on the writer’s map (Plate VI). In view of the very similar lithology throughout the whole sequence from Burindi to the Tamworth beds, it is extraordinarily difficult to decide to which of these groups any isolated outcrop of rock belongs. The Manilla Syncline pitches to the north near Manilla. It is broken along its axis by the Manilla Fault, which may be recognized, particularly in the vicinity of Upper Manilla, where it displaces some of the coarse beds of the Barraba Mudstone. The Wilson Fault, which cuts obliquely across the Syncline, is most probably a thrust. It has brought the strata, which might well have formed part of the eastern limb of the Yarramanbully Anticline, so far to the west that they have become almost continuous with those in the western limb of the Manilla Syncline. The thrust flake is broken by a number of minor fractures. It seems to have moved from the north-north-east towards the south-south-west. A succession of faults, probably most or all of them dipping to the east, has broken the beds of the northern part of the area into a series of small blocks of easterly-dipping Baldwin strata. Benson (1917a, p. 255) wrote of it as ‘‘ schuppen ” faulting, which he suggested took place at approximately the same time as the intrusion of the ultra-basic rocks. Benson mapped the great Baldwin and Black Mountain faults and estimated a throw of 2,000 feet for the latter. The Baldwin Fault, which brings Baldwin rocks into contact with those of the Burindi, is of comparable size. Both of them are more likely to be great thrusts than vertical faults as indicated by Benson on his sections (1917a, p. 254). While simple compression is probably the main cause of the Manilla structures, there appear to have been some torsional movements during the process. The Yarramanbully Anticline pitches to the north; the beds on the north-north-east side of the Wilson Fault appear to have moved from north- north-east to south-south-west, and there seems to have been some rotation of blocks in the Black Mountain area. Moreover, it can be observed in the Nundle district and elsewhere that the Peel Thrust dips steeply to the east. The Fleming, Namoi and some other faults, which run almost in straight lines, also appear to have high dips. It seems possible that some of them could be grouped with the high-angle shears of Carey and Osborne (1938, p. 202, fig. 3). It is suggested here that in the early stages of the compression the area was thrown into a number of folds, those in the west being gentle and those on the east having steeply dipping limbs. Continued pressure produced tight folding accompanied by some strike faulting in the eastern belts and fracturing of the folds to the west. Increasing intensity led to major fracturing and differential movements of various parts of the whole orogenic belt with consequential torsion between these parts. (See sections in text-figure.) ACKNOWLEDGEMENTS. My thanks are due to the N.S.W. Dept. of Lands for supplying the Aerial Photographs and to the Commonwealth Research Grant for expenses involved in carrying out work in the field. REFERENCES. Benson, W. N., 1912. ‘‘ Geology of the Nundle District.”” Rept. A.N.Z.A. Adv. Sci., 12, 100. ————— 1913-1917. ‘‘ Great Serpentine Belt of N.S.W. 1913a. (i) “‘ Introduction.” Proc. Linn. Soc. N.S.W., 38, 490. 19136. (ii) ‘‘ Nundle District,” ibid., 38, 569. 1913c. (iii) “‘ Petrology,” ibid., 38, 662. 1915. (v) “Tamworth,” zbid., 42, 540. 214 ALAN H. VOISEY Benson, W.N., 1917a. (vi) “‘ Western Slopes,” ibid., 42, 224. 19176. (vii) ‘‘ Appendix, Attunga District,” ibid., 42, 693. Brown, I. A., 1942. ‘‘ The Tamworth Series near Attunga.’”’ Tuts JouRNAL, 76, 165. Ce 1937. ‘‘ Carboniferous Sequence in the Werrie Basin.’”’ Proc. Linn. Soc. N.S.W., , 341. Carey, 8S. W., and Browne, W. R., 1938. ‘‘ Carboniferous Stratigraphy, Tectonics and Palzo- geography of N.S.W. and Q’ld.”. Tuis Journat, 71, 591. Carey, S. W., and Osborne, G. D., 1938. ‘‘ Stresses Involved in the Late Paleozoic Diastrophism in N.S.W.” TuxHis JOURNAL, 72, 199. wea T. W. E., 1896. ‘* Radiolaria in Paleozoic Rocks in N.S.W.”’ Proc. Linn. Soc. N.S.W., , 553. 1950. ‘‘ The Geology of the Commonwealth of Australia.” Edward Arnold, London. and Pittman, E. F., 1899. ‘‘ On the Paleozoic Radiolarian Rocks of N.S.W.” Quart. J. geol. Soc. Lond., 60, 16. Hill., D., 1942. ‘‘ Devonian Rugose Corals of the Tamworth District.”” THis JourNnat, 76, 142. Pettijohn, F. J., 1957. ‘‘ Sedimentary Rocks.”? 2e Harper. Raggatt, H. G., 1956. ‘‘ Australian Code of Stratigraphic Nomenclature.” Aust. J. Sci., 18, 117. Spry, A., 1953. ‘‘ Thermal Metamorphism of Portions of the Woolomin Group in the Armidale District. Part I. Turis Journat, 87, 129. ABSTRACT OF PROCEEDINGS. 3rd April, 1957. The combined Annual General Meeting and the seven hundred and twenty-eighth General Monthly Meeting was held in the Hall of Science House, Sydney, at 7.45 p.m. The President, Mr. F. D. McCarthy, was in the chair. Seventy members and visitors were present. The death was announced of Robert D. L. Frederick, a member since 1943. John Craig Cameron was elected a member of the Society. The following awards of the Society were announced : The Society’s Medal for 1956: Dr. W. R. Browne. The Walter Burfitt Prize for 1956: Prof. J. C. Eccles, F.R.S. The James Cook Medal for 1956: Sir Ian Clunies Ross. The Clarke Medal for 1957: Miss Irene Crespin. The Edgeworth David Medal for 1956: No award. The Archibald D. Olle Prize: Dr. R. L. Stanton. The Annual Report of the Council and the Financial Statement were presented and adopted. Messrs. Horley and Horley were re-elected as Auditors to the Society for 1957-1958. The resignations from membership of the Society of Phyllis M. Nicol and Hedley A. Mallaby were announced. The names of R. M. Jones and E. E. Malone were removed from the List of Members in accordance with Rule XVIII. The following accessions have been entered in the library catalogue : parts of periodicals, 54 ; purchased parts, 39. The following papers were read by title only : “‘ Observations on Laterite and Other Ironstone Soils in North Queensland ”’, by D. 8S. Simonett ; “‘ Magnetic Properties of Rocks’, by H. Narain and V. B. Rao; “ Occultations Observed at Sydney Observatory during 1956”’, by K. P. Sims ; ““ A Polarity Reversal in the Tertiary Volcanics of the Kurrajong-Bilpin District, with Petrological Notes’’, by K. A. W. Crook; ‘‘ A Study of River Terraces and Soil Development on the Nepean River, N.S.W.’’, by P. H. Walker and C. A. Hawkins. Office-bearers for 1957-1958 were elected as follow: President.—F. N. Hanlon, B.Sc. Vice-Presidents.—Rev. T. N. Burke-Gaffney, 8.J.; H. A. J. Donegan, M.Se.; F. D. McCarthy, Dip.Anthr.; C. J. Magee, D.Sc.Agr., M.Sc. Hon. Secretaries.—Ida A. Browne, D.Sc.; J. L. Griffith, B.A., M.Sc. Hon. Treasurer.—F. W. Booker, Ph.D. Members of Council.—G. Bosson, M.Se.; G. W. K. Cavill, M.Sc., Ph.D. ; J. A. Dulhunty, D.Se.; A. F. A. Harper, M.Sc.; D. P. Mellor, D.Sc.; W. H. G. Poggendorff, B.Sc.Agr. ; Phyllis M. Rountree, D.Sc., Dip.Bact. ; G. Taylor, D.Sc. B.E. (Mining), B.A., F.A.A.; H. F. Whitworth, M.Sc.; H. Wood, M.Sc. The retiring President, Mr. F. D. McCarthy, delivered his Presidential Address, entitled “Theoretical Considerations of Australian Aboriginal Art’. By courtesy of Dr. T. G. H. Strehlow and the Film Director of the Department of the Interior the colour film ‘“‘ The Native Cat Ceremonies at Watarka’’ was shown. At the conclusion of the meeting the retiring President welcomed Mr. F. N. Hanlon to the Presidential Chair. Ist May, 1957. The seven hundred and twenty-ninth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Mr. F. N. Hanlon, was in the chair. Twenty-two members and visitors were present. Charles Mark Groden was elected a member of the Society. The following paper was read by title only : “‘ The Mineralogy of the Commercial Dyke Clays in the Sydney District, N.S.W.”, by F. C. Loughnan and H. G. Golding. Mr. H. W. Wood, Government Astronomer, gave an address entitled ‘“‘ An Astronomical Tour of England and Ireland ’’. xxii ABSTRACT OF PROCEEDINGS. 5th June, 1957. The seven hundred and thirtieth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Mr. I’. N. Hanlon, was in the chair. Forty-eight members and visitors were present. William Ernest Baker was elected a member of the Society. Professor K. E. Bullen, F.R.S., F.A.A., delivered an address entitled ‘“‘ The Geophysical > Year ’”’. 38rd July, 1957. The seven hundred and thirty-first General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Mr. F. N. Hanlon, was in the chair. Sixty-eight members and visitors were present. Alex Reichel was elected a member of the Society. It was announced that Dr. R. J. Noble, Under Secretary, Department of Agriculture, Sydney, and a member of the Society since 1920, had been honoured by Her Majesty, Queen Elizabeth IT, with a C.B.E. It was also announced that the Clarke Memorial Lecture, entitled ‘‘ Further Remarks on Sedimentary Formations in New South Wales’’, would be delivered by Professor A. H. Voisey, Geology Department, University of New England, on 30th July, 1957. The following papers were read by title only: ‘‘ Minor Planets Observed at Sydney Observatory during 1956’, by W. H. Robertson ; ‘* Ordovician Corals from New South Wales ”’, by Dorothy Hill, F.A.A. The evening was devoted to a symposium on “‘ Biological Effects of Radiation’, and the following addresses were given: ‘‘ Radiation Hazards—Physical Aspects’, by Mr. B. W. Scott, State Bureau of Physical Services, Royal Prince Alfred Hospital; ‘‘ The Effects of Ionizing Radiations on Living Animal Tissues ’’, by Dr. L. E. Atkinson, Department of Medical Physics, St. Vincent’s Hospital ; ‘‘ Present Day Radiation Hazards to Man ”’, by Dr. E. George, Department of Medical Physics, St. Vincent’s Hospital. Tth Auqust, 1957. The seven hundred and thirty-second General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. Rev. T. N. Burke-Gaffney, Vice-President, was in the chair. Fifty-three members and visitors were present. The Chairman announced the death of Orwell Phillips on 28th July, 1957, a member since 1935. It was announced that the following awards were being made available by the Nuffield Foundation Dominion Travelling Fellowships Board: Medicine, 2; Natural Sciences, 2 ; Humanities, 1; Social Sciences, 1. It was also announced that the South-East Asia Treaty Organization is offering, during 1957-1958, research fellowships to scholars of SEATO countries. Notice of motion by the Council that the following alteration be made to the wording of Rule IX: ‘*. . . An absentee member is a member not resident in either New South Wales or the Australian Capital Territory ’’, to replace ‘‘. . . An absentee member is a member who is resident outside New South Wales ”’. On behalf of A.N.Z.A.A.S. the presentation of the Mueller Medal was made to Emeritus Professor A. P. Elkin. The following papers were read by title only: ‘‘ Boundary Stresses in an Infinite Hub of Special Shape’’, by A. Reichel; ‘‘ Basic and Ultrabasic Rocks near Happy Jacks and Tumut Pond in the Snowy Mountains of New South Wales”, by G. A. Joplin; ‘‘ On a Formula of the Convolution Type Related to Hankel Transforms ”’, by J. L. Griffith. The evening was devoted to a symposium on “ Principles of Television ’’, and the following addresses were given: ‘‘ An Outline of the Method of Operation of a Television System ”’, by Mr. W. H. Arnold, Lecturer in Electrical Engineering, N.S.W. University of Technology ; ‘* Non- Entertainment Television ’’, by Mr. C. W. Gidley, Liaison Officer, Amalgamated Wireless (Aust.) Ltd. ; “‘ Producing a Television Show ”’, by Mr. L. A. Major, Production and Programme Manager, ATN Channel 7. ABSTRACT OF PROCEEDINGS. Xxiil 4th September, 1957. The seven hundred and thirty-third General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Mr. F. N. Hanlon, was in the chair. Eighteen members were present. The Chairman announced the death of George Harker on 15th August, 1957, a member since 1905. The following papers were presented: ‘‘ Minor Planets Observed at Sydney Observatory during 1956’, by W. H. Robertson; ‘‘ The Mineralogy of the Commercial Dyke Clays in the Sydney District, N.S.W.”, by F. C. Loughnan and H. G. Golding ; “‘ A Study of River Terraces and Soil Development on the Nepean River, N.S.W.’’, by P. H. Walker and C. A. Hawkins ; “ Ordovician Corals from New South Wales”, by Dorothy Hill, F.A.A.; ‘‘ Boundary Stresses in an Infinite Hub of a Special Shape ”’, by A. Reichel ; ‘‘ On a Formula of the Convolution Type Related to Hankel Transforms’”’, by J. L. Griffith. 2nd October, 1957. The seven hundred and thirty-fourth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Mr. F. N. Hanlon, was in the chair. Thirty-six members and visitors were present. Herbert Gordon Roberts was elected a member of the Society. The President moved the following motion—Alteration of wording of Rule IX : ‘‘ An absentee member is a member not resident in either New South Wales or the Australian Capital Territory ”’, to replace ‘‘ An absentee member is a member who is resident outside New South Wales”. A vote was taken, with twenty-six members voting for the motion, against—nil. It was announced that the motion would be submitted for confirmation at the next General Monthly Meeting. The following paper was read by title only: ‘‘ The Geochemical Behaviour of Elements in Meteorites ’’, by J. F. Lovering. The evening was devoted to a symposium on *‘ Beach Sands of Australia ”’, and the following addresses were given: ‘‘ Growth and Development of the Beach Sands Industry ”’, by Mr. E. J. Harrison, Senior Geologist, Department of Mines, N.S.W.; ‘‘ Mining Methods and Restoration Procedure on Beach Sands Leases ’’, by Mr. B. A. Hadley, Senior Inspector of Mines, Department of Mines, N.S.W. 6th November, 1957. The seven hundred and thirty-fifth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Mr. F. N. Hanlon, was in the chair. Fifteen members were present. The following resignation was received: Professor Alan J. Birch. The evening was devoted to a Commemoration of Great Scientists, and the following addresses were given: ‘‘ Alfred Binet and Mental Measurement’, by Mr. A. G. Hammer, Department of Psychology, University of Sydney; ‘‘ Karl Pearson—Founder of a Science”’, by Professor G. Bosson, School of Mathematics, N.S.W. University of Technology ; ‘‘ Ronald Ross and Mosquito Day—The Conquest of Malaria’’, by Professor Harvey Sutton, O.B.E. 4th December, 1957. The seven hundred and thirty-sixth General Monthly Meeting was held in the Hall of Science House, Gloucester Street, Sydney, at 7.45 p.m. The President, Mr. F. N. Hanlon, was in the chair. Sixty-four members and visitors were present. The following were elected members of the Society : Brian Edward Clancy, U. Hla, Frank Leechman and Barry S. Thornton. The following names were removed from the list of members in accordance with Rule IX : G. H. Burton, R. Everingham, L. Luber and W. P. Sergeyeff. Xxiv ABSTRACT OF PROCEEDINGS. The motion by the Council (alteration of wording of Rule IX), carried at the October General Monthly Meeting, was confirmed: ‘‘ An absentee member is @ member not resident either in New South Wales or the Australian Capital Territory ”’, to replace ‘‘ An absentee member is a member who is resident outside New South Wales ”’. The following papers were read by title only : ‘‘ Addendum to my paper ‘ On Weber Trans- forms’’’, by J. L. Griffith ; ‘‘ The Zeros of a Certain Function Involving Bessel Functions ”’, by J. L. Griffith; ‘‘ Tapiolite and the Tri-rutile Structure ”’, by Florrie M. Quodling ; ‘‘ The Manilla Syncline and Associated Faults”’, by A. H. Voisey. The evening was devoted to a seminar on “ Artificial Satellites ’’, and the following addresses were given: “* Radio Methods of Tracking Artificial Satellites ’’, by Dr. D. L. Hollway, C.S.I.R.O. Division of Electrotechnology ; “‘ The Scientific Uses of Artificial Satellites ’’, by Mr. C. A. Shain, C.S.I.R.0., Division of Radiophysies ; “‘ The Motion of Artificial Satellites ’’, by Mr. H. W. Wood, Government Astronomer, Sydney Observatory. NOTICE. Tue Roya 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, it assumed its present title, and was incorporated by Act of the Parliament of New South Wales in 1881. FORM OF BEQUEST. | hequeath the sum of £ to the Royat Society oF NEw SoutH WALES, Incorporated by Act of the Parliament of New South Wales in 1881, and I declare that the receipt of the Treasurer for the time being of the said Corporation shall be an effectual discharge for the said Bequest, which I direct to be paid within calendar months after my decease, without any reduction whatsoever, whether on account of Legacy Duty thereon or otherwise, out of such part of my estate as may be lawfully applied for that purpose. [Those persons who feel disposed to benefit the Royal Society of New South Wales by Legacies are recommended to instruct their Solicitors to adopt the above Form of Bequest.] TO AUTHORS. Particulars regarding the preparation of manuscripts of papers for publication in the Society’s Journal are to be found in the ‘‘ Guide to Authors ”’, which is obtainable on appli- cation to the Honorary Secretaries of the Society. The previous volumes and separate parts of the Journal and Proceedings may be obtained at the Society’s Rooms. The Library and Reading Room of the Society at Science House, Gloucester and Essex Streets, Sydney, is available for the use of members on week-days, 10 a.m. to 12 noon and 2 p.m, to 4 p.m. INDEX A Page Absentee Members—Alteration of Rule IX (Emen. 1955) aie ae Xxiv Abstract of Proceedings Ais 12.0.4 Alteration of Rule IX (Emen. 1955) Xxiv Annual Report of the Council . i A.N.Z.A.A.S. Meeting, Dunedin, N. Z., Society’s Delegate iE il A Polarity Reversal in the "Tertiary Voleanics of the Kurrajong- st ee District, by K. A. W. Crook 57 Archibald D. Olle Prize Sry P22 Archibald D. Olle Prize: Award to R. L. Stanton .. we ae i Associate Members F XV A Study of River Terraces and Soil Development on the Nepean River, N.S.W., by P. H. Walker and C. A. Hawkins 67 Australian Aboriginal Art, Theoretical Considerations of, Presidential Address, by F. D. McCarthy .. ye be a) Authors, Guide to 5 a XxXiv Awards of the Society .. we XViil B Balance Sheet oe Ul Basic and Ultrabasic Rocks near r Happy Jacks and Tumut Pond in the Snowy Mountains of N.S.W., by G. A. Joplin 120 Bequest, Form of XXiv Bessel Functions, The Zeros of a Certain Function Involving, by J. L. Griffith 190 Boundary Stresses in an Infinite Hub of Special Shape, by A. Reichel. . 109 Browne, W. R.—Award of the Society’ s Medal for 1956 ; i Burfitt Bre Awards of the at Sb) Se Burfitt, W. F.—Obituary Notice sic Ail Cc Clarke Medal, Awards of the .. XViii Clarke Memorial Lectures XVil Clarke Memorial Lecture for 1957, ee A. H. Voisey .. we LGS Commemoration of Great Scientists “xxiii Commercial Dyke Clays in the Sydney District, N.S.W., The Mineralogy of, by F. C. Loughnan and H. G. Golding 85 Cook Medal for 1956, Award of the James i Corals from New South Wales, Ordo- vician, by D. Hill a0 5 Council, Annual Report of the. 1 Crespin, Irene—Award of the Clarke Medal for 1957 i Crook, K. A. W.—A Polarity Reversal in ‘the Tertiary Voleanics of the Kurrajong-Bilpin District, with Petro- logical Notes .. : a WY D David Medal, Awards of the Edgeworth xix E Page Eccles, J. C.—Award of Burfitt Prize for 1956 ond aid bye ae i Edgeworth David Medal, List of Awards .. oro) KEK Elkin, A. P. Presented with Mueller Medal... Ze ae Heoe.O.9b1 F Further Remarks on Sedimentary Forma- tions of New South Wales, Clarke Memorial Lecture, by A. H. Voisey .. 165 Frederick, R. D, L.—Obituary Notice... vii G Geochemical Behaviour of Elements in Meteorites, by J. F. Lovering .. 149 Geology, Report of Section of . vi Golding, H. G.—See Loughnan, F. C., and Golding, H. G. .. . 85 Government Grant to Society . Bre i Griffith, J. L.— (a) On a Formula of the Convolution Type Related to Hankel Trans- forms st SG de .. 142 (6) Addendum to My Paper on ““Weber Transforms” .. 189 (c) The Zeros of a Certain Function Involving Bessel Functions .. 190 Guide to Authors. . a ae XxXiv H Hankel Transforms, On a Formula of the Convolution Type Related to, by J. L. Griffith .. 142 Hawkins, C. A.—See Walker, Pp. H., and Hawkins, C. A. .. 67 Hill, Dorothy— Ordovician Corals from New South Wales ‘ Ss Samet) Honorary Members, List of o3 oe Xvi J James Cook Medal, List of Awards XVili James Cook Medal for 1956—Award to Sir Ian Clunies Ross .. i Joplin, Germaine A.—Basic and Ultra- basic Rocks near Happy Jacks and Tumut Pond in the Snowy Mountains of N.S.W. 55 ee 42 Fe UAV L Laterite and Other Ironstone Soils in North Queensland, Observations on, by D. G. Simonett .. te ae a) Lise, of Members .. 2 Ac .. Vill Liversidge Research — Lectureship, Awards of the .. bE ie dip 3.e8 XXvi Page Loughnan, F. C., and Golding, H. G.— The Mineralogy of the Commercial Dyke Clays in the Sydney District, INGE Ws. 2 85 Lovering, J. F.—The Geochemical Be- haviour of Elements in Meteorites .. 149 M Magnetic Properties of Rocks, by H. Narain and V. Bhaskara Rao .. 36 Manilla Syncline and Associated Faults, by A. H. Voisey ss or Ay PAU) Members, List of . ae So eagtl Members, List of Honorary Si XVi Meteorites, The Geochemical Behaviour of Elements in, by J. Lovering .. 149 Mineralogy of the Commercial Dyke Clays in the Sydney District, N.S.W., by F. C. Loughnan and H. G. Golding 85 Minor Planets Observed at Sydney Observatory during 1956, by W. H. Robertson we i cs Hen Oe Mueller Medal, Presented to A. P. Elkin Ki5-o.cbt N Narain, H., and Rao, V. Bhaskara— Magnetic ‘Properties ‘of Rocks eo O Notices . { XXi1V oO Obituary .. ; vil Observations on Laterite and Other Ironstone Soils in North Queensland, by D. G. Simonett .. 23 Occultations Observed at Sydney Ob- servatory during 1956, by K. P. Sims 55 Officers for 1957-1958 .. : ~ Xk On a Formula of the Convolution Type Related to Hankel Transforms, by J. L. Griffith .. 142 Ordovician Corals from New South Wales, by Dorothy Hill ae ate 55 Oe P Presidential Address—Theoretical Con- siderations of Australian Aboriginal Art, by F. D. McCarthy ae Bae 08 Q Quodling, Florrie M eee St: and the Tri-rutile Structure .. oT R Rao, V. Bhaskara.—See Narain, ae and Rao, V. Bhaskara a6 36 Reichel, A.—Boundary Stresses in an Infinite Hub of Special Shape ee LO9 Report of Council, 1956-1957 .. ote i Report of Section of Geology .. vi River Terraces and Soil Development o on the Nepean River, N.S.W., A Study of, by P. H. Walker and ©. A. Hawkins... 67 INDEX. Page Robertson, W. H.—Minor Planets Ob- served at Sydney Observatory during 1956 Ross, Ian Clunies—Award of the James Cook Medal for 1956 Ss Science House Management Committee— Society’s Representatives Section of Geology, Report of . Sedimentary Formations of New South Wales, Further Remarks on, Clarke Memorial Lecture, by A. H. Voisey. s Simonett, D. G.—Observations on Laterite and other Ironstone Soils in North Queensland es Sims, K. P.—Occultations Observed at Sydney Observatory during 1956 Snowy Mountains of New South Wales, Basic and Ultrabasic Rocks near Happy Jacks and Tumut Pond in the, by G. A. Joplin a Society’s Medal, List of ‘Awards : Society’s Medal for 1956—Award to W. R. Browne . Soil Development 0 on the Nepean River, N.S.W., A Study of River Terraces and, by P. H. Walker and C. A. Hawkins Sydney Observatory, Minor Planets observed during 1956 at aie Sydney Observatory, Occultations observed during 1956 at T Tapiolite and the Tri-rutile Structure, by F. M. Quodling Tertiary Volcanics of the Kurrajong- Bilpin District, N.S.W., A Polarity Reversal in the, by K. A. W. Crook... Theoretical Considerations of Australian Aboriginal Art—Presidential fone. by F. D. McCarthy Vv Voisey, A. H.— Clarke Memorial Lecture—Further Remarks on Sedimentary Forma- tions in New South Wales The Manilla Bymelne and Associated Faults Ww Walker, P. H., and Hawkins, C. A.— A Study of River Terraces and Soil Development on the meee River, IN-SS Wis gers Weber Transforms, Addendum to My Paper on, by J. L. Griffith .. A Z Zeros of a Certain Function Involving Bessel Functions, by J. L. Griffith .. 165 lees . 165 209 67 . 189 190 NOTICE, Tur Royat Socrmry 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, it assumed its present title, and was incorporated by Act of the Parliament of New South Wales in 1881. FORM OF BEQUEST. gd bequeath the sum of £ to the Royat Socrmry or New Sours Wats, Tncorporated by Act of the Parliament of New South Wales in 1881, and I declare that the receipt ~_of the Treasurer-for the time being of the said Corporation shall be an effectual discharge for the said Bequest, which I direct to be paid within calendar months after my decease, - without any reduction whatsoever, whether on account of Legacy Duty thereon or otherwise, out of such spent of my estate as may be lawfully applied for that purpose. [Those persons who feel disposed to benefit the Royal Society of New South Wales by Legacies are. eGo to instruct their Solecvor to. adopt ate above Form of Bequest. | TO AUTHORS. : Particulars regarding the preparation of manuscripts of papers for publication in the -Society’s Journal are to be found in the ‘‘ Guide to Authors’, which is obtainable on appli- cation to the Honorary Secretaries of the Society. The previous volumes and separate parts of the Journal and Proceedings may be obtained at the opebe a] Rooms. nae ‘The Library and Reading Room of the Society at Science House, Gloucester and Essex sak Streets, Sydney, i is available for the use of eg ee on week-days, 10 a.m. to 12 noon and 2 p.m, to 2 P TO CONTENTS VOLUME XCI Part IV Beers Page ART. XV.—CLARKE MEMORIAL LECTURE. FURTHER REMARKS ON = SEDIMENTARY FORMATIONS IN N.S, WALES. A. H. Voisey ais 4 6D ART. XVI.—ADDENDUM TO My PaApER ‘*‘ ON WEBER TRANSFORMS ”’. Jd. L. Griffith .s ge i ase tas 2% =: gins 189 Art. XVII.—THE ZEROS OF A CERTAIN FUNCTION INVOLVING BESSEL Functions. J. L. Griffith aa a bd ‘a ane .. 190 Art. XVITI.—TAPIOLITE AND THE TRI-RUTILE STRUCTURE. Florrie iu. ‘ge Quodling .. ae ae oe ga ee ae ot eat PLOT Art. XIX.—THE MANILLA SYNCLINE AND AssocraTEeD Fautts. A. ZH. Voisey tg = te = a es ae Ye 547-208 ABSTRACT OF PROCEEDINGS .. ee bis ae ny s oat xxi INDEX Sy sph oh he ee we a Se te aos TITLE PAGES FOR COMPLETE VOLUME FOR 1957. Vou. XCI, Parts I-IV xxvii THE AUTHORS OF PAPERS ARE ALONE RESPONSIBLE FOR THE STATEMENTS MADE AND THE OPINIONS EXPRESSED THEREIN AUSTRALASIAN MEDICAL PUBLISHING CO. LTD. SEAMER AND ARUNDEL STS., GLEBE, SYDNEY MCZ ERNST MAYR LIBRARY wii Ce oe en * ye a eine ee eg tn rg Oe — oe aren