SMITHSONIAN _ LIBRARIES - <= x RA = ep a ZL j Om NOILALIL LIBRAR! LIBRAR! * 2 ar | Cc a O za NOILNLIL RIES SMITHSONIAN INSTITUTION NOILALILSNI NVINOSHLINS Satuvd = 3 F m NSS OE | 25 = 4 s RW > EY oa = =a VU Do a = £ = » ee he o = HN LILSNI_ NVINOSHLIWS | S3 luvUdIT_LIBRARI ES SMITHSONIAN _ INSTITUT = oe = - ey A) i > 8) — ap) nana (ap) em tA ALILSNI_ NVINOSHLIWS $3 ldvUIT_LIBRARI ES SMITHSONIAN _ INSTITU’ z . ne et S z Xe. f Wad a ee i z y, y 4 = is a ; aE S bi 2 a © Le Oo a Ul? _ 2 E z _ PAR | ES SMITHSONIAN INSTITUTION NOILNLILSNI_NVINOSHIINS | S3 uve — Sa yreew of _ te ce A 2 _ c = a < fA oc c ang a fm es = = As Oo Bp = oO eer ro) Ae = 4 aS = ARI ES SMITHSONIAN INSTITUTION NOIJLNLILSNI NVINOSHLINS S3IyVYy mi = ye = - z ° “0 © a s) \ OE oy - : = i > =) sae — iS - cate fm ee ine be ics = | OS Z a Z NVINOSHLINS S3SIYVURIT SMITHSONIAN INSTITUT Pa DY =< Y = << = ee = < S 2 ly 5 = S y 2 ee @ 2 | Y * 2 “iy = Z as y Ss > ™ = > = | wn a w) Meee : o : ARI ES SMITHSONIAN INSTITUTION NOILALILSNI NVINOSHLINS S3iuWY Ip n ui i Ao . al | << 5 LIBRARIES S3J1u¥vuditT LIBRARIES INSTITUT i7] LIBRARIES iN SMITHSONIAN INSTITUTION NOILNLILSNI INSTITUTION NOILALILSNI S3IYvVYNSIT LIBR af NS Saiyvagd! saiuvuag “ss ARIES SMITHSONIAN INSTITUTION NOILNLILSNI NVINOSHLINS S3IuVys wn = z g Z zs yf = = oN 4 z 4 eo \ ,, é s WW A 8 z PBs eK TAS O 28 O 2 E Ww 2Z. = Z, : ee les : : _NVINOSHIUIWS SaINVUIT LIBRARI ES SMITHSONIAN _INSTITUT & wl a ul a a a = a ae ao a — < * 4 ce SMC ce = 2 WN a = cn = ae — oO aa fo) = ood = al = SMITHSONIAN INSTITUTION NOILMLILSNI SAluvy: o i 5 ~ S a = ow = EY ca Ee aM Ee - - cid E ca i = m ” m w”) = ‘i = = w = w” ae _NVINOSHLINS Sa luYvug MIout BRARI ES SMITHSONIAN _ INSTITUT < 2 = Ne = = Xs WE = Z AS = ZINN hf S = oN, s ANN iy, = O % 1 eo) Ae \ UV * Z fe x» 2 E ME z he ' RIES SMITHSONIAN INSTITUTION NOILNLILSNI NVINOSHLINS S3IuVU! S 5 ‘ y = i} Wl / ain reo. ay 90 Gj | 5 £ ia Published monthly by the New York State Education Department DECEMBER 1905 ON ew York State Museum - Joun M. CLARKE iaice BULLETIN 362 Bulletin 96 GEOLOGY 10 GEOLOGY 3 sti OF THE PARADOX LAKE QUADRANGLE, NEW - YORK A \ Et IDA H. OGILVIE i ; PAGE PAGE MUBGOGTCTION so. 6005.2 she een oes 461 Glacial deposits and drainage Topography and geology of the modifications) 7s). .2 00.6 469 PMC OMTCA GIS) .,/6....'- NEW YORK 3si A 0H Meu SE UNE sand, or silt, with a stratified structure. The first class comprises what is generally known as till, and as boulder clay, and is generally sprinkled over the surface. The stratified deposits overlie the thin till covering, but the two were probably laid down contemporane- ously in different localities, some till being formed at the margin of the ice at the same time that aqueous deposits were gathering farther from its edge. No true moraines were found within the limits of this quadrangle. Ridges of rounded glacial hills occur in several localities, but they all proved to be of fine stratified material. The region lay so far within the ice sheet that any deposits formed in its advance would subsequently have been removed, and the same would be true of any earlier gravels which may once have been there. The surviving deposits belong to the time of retreat and melting of the ice, at the close of its last invasion. The erosion history and glacial phenomena of the Adirondacks as a whole were summarized by the writer in a recent paper! In this paper it was shown that the general direction of ice movement was toward the southwest; that the motion was vigorous among the out- lying lower hills, but that among the higher mountains the ice was stagnant in the bottoms of the deep valleys, while at the time of the maximum extension of the ice sheet it passed over the tops of these filled valleys smoothing the mountain summits. It was further shown that the glacial deposits belong in general to the time of retreat and melting of the ice, being largely of stratified material. The Paradox Lake quadrangle lies on the border between the regions exhibiting the two types of glaciation. Its northwestern part lies in the region of high peaks and deep valleys, where there is little sign of glaciation except in the smoothed tops of the moun- tains. The more southerly and easterly parts of the quadrangle were in the region of the southwesterly moving ice current, hence smoothed rock faces and roches moutonnées are common, as are also glacial deposits. Crown Point. In the northeastern corner of the quadrangle, 900 feet above sea, in the valley about two miles south of Towner pond 1On Glacial Phenomena in the Adirondacks, Jour. Geol. v.10 April-May, IQOT. a ee ee ee ee GEOLOGY OF THE PARADOX LAKE QUADRANGLE 471 and the same distance north of Sherman Corners, is the flat bed of what was probably a small glacial lake. This lake was of short duration, not lasting long enough for the development of shore features. It was formed by the damming of a preglacial channel by the retreating ice, and its waters were supplied in part from the melting edge of the ice and in part from the eastward flowing drain- age of the valley. At the margin of the ice, stratified drift hills were deposited which blocked the valley on the east after the ice miad retreated: The water speedily found a new outlet farther south and the lake was drained. } | At present the stream meanders over the old lake flat, having cut its channel and built a flood plain below the lake level. Its pre- glacial outlet is blocked by the ridge of stratified hills, and where it meets them the stream turns southward. The road to Crown Point now runs through the preglacial valley, and a branch road to the north has cut through one of the stratified hills, whose material is now being removed for gravel. In this exposure beds of ‘coarseness varying from very fine silt to pebbles of about two inches are seen, with some cross-bedding. Farther east beyond the line of these hills typical boulder clay is found. _ The stream has cut a postglacial channel around the hills that blocked its old valley, and after rounding them to the south it turns northward again, cascading over ledges of Potsdam sandstone and cutting a little canyon. The drift dam was formed at the top of a steep hill, which leads downward to Lake Champlain, and the stream descends this hill through a postglacial valley. After reaching the lower level it turns northward and reenters its preglacial valley. At the foot of the hill is another small flat which may represent another temporary lake, but its complete interpretation needs investi- gation beyond the limits of this quadrangle. Stratified deposits are also present along the valley leading northward from this glacial lake to Towner pond, these deposits being extensively eroded post- glacially. Like the hills of the dam just described, these deposits show great variation in size of material and often cross-bedding. They were evidently formed by swift waters, and probably repre- sent glacial outwash. . | Age NEW YORK STATE MUSEUM Towner pond is held up by an artificial dam sixteen feet high, the original pond being a small solution basin in the limestone at the eastern end of the present pond. The artificial dam has resulted in drowning several tributary valleys. At its principal inlet is a fall and a small natural bridge over crystalline limestone [pl. 6]. This fall is postglacial. East of the pond, surface drift is abundant, some true till being present [pl. 7]. No well data are available, but the topography suggests an eastward preglacial outlet. The valley leading westward towards Overshot pond is filled with . much drift, mainly sand and gravel. Several ridges of terminal morainic aspect are present, running in a general east and west direc- tion. There were no cuts into these ridges. To the west, at the end of the trail, the valley broadens out in a manner abnormal for the upstream part of a small creek. A sand flat fills the bottom of this basin. No lake shore features were found about this flat; it probably represents a lake whose life was of short duration. Ticonderoga. Three miles north of Chilson is a line of kames,) extending southwest for a mile and crossing the angle of the main road where it turns westward. A cut across one of these shows the material to be sand, the bedding highly inclined. Emmons in his report refers to the ridge. Immediately south of this ridge lies a swamp, its flat extending about a mile in each direction, inclosed on three sides by gneissic hills, on the fourth by the ridge of kames. Its outlet cuts across the kame belt and cascades westward through a postglacial valley into Putnam creek. The probable history of the drainage in’this region is illustrated in the diagrams [fig. 1-3]. Figure I represents the normal river valley which would result were all Potsdam deposits, faults and glacial drift removed. Figure 2 represents the same region after the Potsdam deposits had filled the valley and the work of reexcavating had only partly foilowed the old channels; the basins of Putnam pond, North pond, Rock pond and Bear pond had been added by faulting. Figure 3 represents the "A kame is a hill or short ridge of stratified glacial drift. Kames were formed at the edge of the ice, of material which had been transported by the ice, deposited by water issuing from the ice. Pe ee a ee Fig. 1 Mt Treadway from Pharaoh lake. Peneplain cut on sedimentary gneiss Fig.2 Mt Treadway from Pharaoh lake. Peneplain cut on sedimentary gneiss SUOJSOUM] UL ISplIq [einjeu [[eWG ‘“puod s9uMOT jo JolUT 9 281d GEOLOGY OF THE PARADOX LAKE QUADRANGLE 473 Fig. 1 Hypothetical Prepotsiam drainage ATA. NEW YORK STATE MUSEUM | We Bear Pand Goose ond Rot Ik = < 6 z Q ow” ov Ce Fig. 2 Hypothetical. drainage at a time later than the Siluric; later thanjthe faulting; before the ice invasion — puod 10uMOT, FO YNOS f]]TT 4 9eld GEOLOGY OF THE PARADOX LAKE QUADRANGLE 475 present drainage, the additional lakes being caused by drift-filling or postglacial water-laid deposits, with the exception of Penfield pond, which is partly artificial, The swamp in the southwest corner Fig. 3 Present drainage is the one above referred to and probably represents a lake of Champlain age. | Hague. The brook in. the southeastern corner of the quadrangle } flows through a broad preglacial valley, now filled with rolling hills 476 NEW YORK STATE MUSEUM of stratified drift. The upper course of the present stream is super- imposed over this drift-covering and wanders considerably, having developed a broad flood plain in its upper course. No evidence was found of a glacial lake in this locality, the evidence pointing towards the filling of the valley by drift deposited by the escaping floods from the melting ice. Rock first appears at the bridge (one inch from the eastern end of the map) and downstream ‘from this point the course alternates between quiet reaches, where the stream flows over drift or along the strike of the gneiss, and little cascades and rapids, where it flows southward down the dip. At the largest fall the Hague gristmill is situated, the fall in this case resulting partly from a soft, easily eroded shear-zone in the gneiss at the base of the present fall. Below this fall the stream bed is full of loose material, in part at least of postglacial origin and resulting from the cutting back near the fall. A similar fall occurs at the corner of the map. ; Potholes are found at these falls, and at the one at the gristmill a little lake has been formed part way down the fall from the wearing away of a soft layer [pl. 8, fig. 1]. Trout brook also flows through an old drift-filled valley, slowly meandering in its upper course, and alternating between quiet reaches and rapids, according to whether its drift cover is or is not cut through. The rock. here being massive, no such changes can be seen as in the southern brook. Close to the edge of the map Trout brook reaches the Potsdam sandstone and turns abruptly northward. It leaves an open valley only three fourths of a mile in length which leads east straight to Lake George, and turns abruptly northeast, emptying into Lake Champlain six miles away. Its lower course is on the Ticonderoga quadrangle. This northeastward bearing valley is a very old one. Small ex- posures of limestone indicate that it was originally excavated upon a limestone fold. The Potsdam sandstone lies undisturbed in three localities on its lower course, suggesting that the valley existed in Cambric time and that it was drowned by the Potsdam sea. In Champlain time the valley was occupied by the water, probably of an arm of Lake Hudson—Champlain. Since the shrinkage of this t k Fig. 1 Hague grist mill. Cascade down the dip of quartzite Fig. 2 Pond in cirque, Skiff mountain GEOLOGY OF THE PARADOX LAKE QUADRANGLE 477 glacial lake, the lower Trout brook has reestablished itself in this old valley and has beheaded upper Trout brook whose former course was eastward, over hard gneisses. Horicon and Schroon. Pharaoh lake and Wolf and Whortleberry ponds lie in rock basins caused by faulting. The outlets of Pharaoh lake and of Whortleberry pond join, and together are combined with Desolate brook. The junction of these three streams takes place in a broad valley filled with stratified drift. Desolate brook is now a swamp or “ vly,’ b its still waters having been filled with sphagnum and other vegetation. The trail mapped is now impassable owing to the increasing swampy conditions. At the northern end of Schroon lake is a wide flat extending northward for about three miles. This flat appears to be a glacial delta. At present the Schroon river meanders over its surface, and the greater portion of the flat is swampy. Schroon and North Hudson. The Schroon river in its south- westerly course extends for about five miles within the limits of the quadrangle. On its banks are well-developed terraces. | In the course of these five miles the river descends 50 feet. Its most conspicuous terrace drops from 960 feet in the north to 930 in the south—3o foot fall in the same distance in which the present river falls 50 feet. The surface of this terrace is slightly uneven and suggests an origin as a kame terrace, while the ice still stood in the valley. The front of this terrace has been extensively eroded, in part by the Schroon river, which has built a lower terrace of flood plain origin, and in so doing has worn back the face of the older one; in part by recent gullying. Gullies once started grow with astonishing rapid- ity, houses and the highways being frequently undermined. The ‘material of this terrace is sand. : z A higher terrace is to be distinguished at a few localities. This higher terrace is partly built, partly cut. It occurs 35 feet above the main terrace. Through the Schroon valley sand dunes abound, the material loosened along the gullies being blowm by the wind and deposited on either of the two lower levels. The main terrace of the Schroon extends up its tributary, Black brook. 478 NEW YORK STATE MUSEUM Cirques! and grooves. Glacial cirques are found in at least three instances within this region. One of these is on the southern slope of Cat mountain, near the northern boundary. This cirque contains a small pond which is not on the map. A second is on the southern slope of Skiff mountain [pl. 8, fig. 2] and also contains a pond. The third is on the southwestern slope of Mount Steven; this one does not contain a lake. On the northern shore of Paradox lake is a large glacial groove, displaying a smoothly polished surface [pl. 9, fig. 1 and 2]. Striae are rare. Those found have already been recorded. Boulders are common, some of considerable size. “These boulders are off all kinds of Adirondack rocks, Potsdam sandstone being very common. PART 3 General geology The crystalline rocks of the Adirondacks are part of the great series forming the Laurentides of Canada. It has never been doubted that these crystalline rocks are of Prepotsdam age. The Potsdam sandstone lies almost undisturbed upon their eroded surfaces, and in Prepotsdam time the Precambric sediments had been tremendously folded and faulted and intruded at great depths by at least one series of plutonics. They had then been uplifted and worn down many thousands of feet until only the cores remained, and until their surfaces had attained a topography of only moderate relief. This surface had then sunk beneath the advancing Potsdam Sea. Distribution and character of formations. The crystalline com- plex consists in part of sedimentary rocks, lithologically identical with the Grenville series of Canada; in part of intrusives, which resemble the Norian series of Canada, and in part of other intrusives being of different character. *A cirque is an amphitheater with precipitous or very steep sides -which is excavated by a glacier at its upper portion. The ice cracks off and carries away the rock from the mountain until by edting backward it leaves these ‘precipitous walls surrounding the valley on all sides except its outlet. Cirques often contain small lakes. Fig. 1 Glacial groove. North shore of Paradox lake Fig. 2 Glacial groove. North shore of Paradox lake ; * é . a J { j j = A GEOLOGY OF THE PARADOX LAKE QUADRANGLE 479 Sediments of the Grenville series. Probably the oldest rocks on the quadrangle are metamorphosed sediments. Probably also only one series of Precambric sediments is present. Six types of sedi- mentary rocks are recognized: hornblende gneiss, limestone, mica schist, silimanite gneiss, graphitic quartzite, shaly quartzite. Hornblende gneiss. Typically this rock is a very quartzose horn- blendic gneiss. It is of gray color. Its sedimentary origin is indi- cated by its large quartz content; by certain persistent streaks of brotite schist which appear to represent changes in composition which could only be explained by changes in sedimentation from sandy conditions to shaly ones; and by its vertical changes in min- eral composition [see pl. 4, fig. 1]. The gneiss extends in a horseshoe-shaped belt through the central, southern and western portions of the quadrangle, containing within its area some of the most important mountains, namely, Treadway, Putnam, Stevens, Third Brother, Park and others. This gneiss is so excessively crushed, and also so much altered by syenites, pegmatites and quartz veins, that no structural features could be made out. Limestone. Closely associated with the gneiss occurs crystalline limestone. It is a completely recrystallized rock, which presents such remarkable metamorphic features that it was first supposed by Emmons to be of igneous origin. Little trace of bedding is to be found. While at times almost pure, it often contains metamorphic minerals, such as graphite, apatite, pyroxene, amphibole, phlogopite, biotite, scapolite, garnet, titanite, pyrrhotite and tourmaline. Most of these minerals are clearly the result of regional metamorphism acting upon impure limestone, but some of them, notably tourmaline, titanite and_scapolite, are the result of contact metamorphism. In Moriah, just north of the region covered by this map, the limestones are found charged with serpentine, forming the rock known as ophicalcite. | *Gneiss is a laminated metamorphic rock having the mineral composition of a granite, but not necessarily in the same proportions. Varieties are indicated by prefixing the name of the most important silicate, thus hornblende gneiss is a rock containing quartz, feldspar and hornblende. 480 NEW YORK STATE MUSEUM 7 These limestones undoubtedly represent calcareous sediments charged with magnesia, iron, silica and alumina, the latter elements forming the various silicates during metamorphism. Graphite is almost universally present. } The intense metamorphic changes which result in great contortion or complete crushing when applied to sandstone result in flowing and recrystallization when applied to limestone. The crystalline lime- stones of the Adirondacks have lost their original features and with recrystallization have developed polysynthetic twinning, parallel 1% R. The limestone is thoroughly crystalline throughout its extent, and its condition can not be explained as a result of contact meta- ‘morphism from the associated intrusions. Contact effects have been described by various writers in various Adirondack localities, but on the Paradox Lake quadrangle the contact metamorphism resulted in changes in the intruded rock. The limestone is found in the wider valleys in long belts and in a few isolated patches among the hills. One long strip of it lies along the Paradox valley, while another forms the shores of Penfield pond. Gneiss and schist are often interbedded with it, and the dip can sometimes be discovered from these layers. ‘The limestone itself is so completely recrystallized that as a rule no bedding can be made out. The only locality where a dip and strike could be determined in the pure limestone was in a little canyon on the south side of Paradox lake, where there was a little cave in the side of the cliff, Similar caves are common, and so are — natural bridges | and other forms resulting from solution. In the northwestern part of the Penfield pond limestone belt are a series of little hills of limestone interbedded with gneiss. Near Dudley pond the outcrop of alternating gneiss and limestone is repeated by a fault, the beds here dipping gently east. Farther south the limestone becomes purer; its associated gneiss stands out as several good sized hills, and no interbedding is. seen. Mica schist.1 Typically a biotite schist, containing occasionally a little hornblende, and sometimes grading into a eneiss this rock *Schists differ from gneisses in that they ! have finer laminations. They often have the same mineral composition as the gneisses, hut sometimes are more basic. They are classified according to the principal dark silicate present. Plate 10 Trap dike in gneiss, north shore of Pharaoh lake. The trap weathers more readily than the gneiss a ra GEOLOGY OF THE PARADOX LAKE QUADRANGLE 481 invariably accompanies the sedimentary gneiss and the limestone, It occurs in bands interbedded with limestone or gneiss, the bands varying from a few inches to some feet in thickness. They are never of sufficient size to be mapped separately. The association of limestone with schist and with banded gneiss has frequently been noted in the Adirondacks. In the Paradox Lake quadrangle the rocks were so involved and exposures so limited that no stratigraphy could be made out. . The relations, however, were shown in a locality about forty miles to the west, in a gorge cut by the Hudson river. Between the points where the Indian and the Boreas rivers join the Hudson there are about eight miles of rapids, frequently bounded by cliffs. Here a section is displayed, notably in the cliffs forming the “ Blue Ledge” and in the cliffs above “Carter’s Riff.” It is evident that gneiss, schist and lime- stone constitute a single conformable series, the gneiss being beneath, the schist forming bands interstratified with both gneiss and limestone. It is further evident that the contact between gneiss and limestone is not a sharp one. ‘There is an alternation of thin beds of gneiss and of limestone, passing upwards into pure limestone. The evidence from the gorge of the Hudson can certainly be applied to the same rocks when too much crushed to show structural relations. In the Paradox Lake quadrangle both faulting and crush- ing have been excessive, but it is safe to conclude that here also the gneiss is beneath, the limestone above, with moye or less inter- mingling along the contact. Sillimanite gneiss. The outcrop of this rock at the mine at Graphite has already been described by Professor Kemp.! Both the foot and the hanging walls of the mine consist of it. The garnet and graphite are the only minerals to be distinguished in the hand specimen. The graphite of the mine is developed in a quartzose layer along which there has been shearing in the direction of the bedding. Another occurrence of sillimanite gneiss is on Bear Pond moun- tain, but it differs slightly from that at Graphite. Garnets made *Geology of Washington, Warren and Essex Counties N. Y. State Geol. 17th An. Rept 1899. p.530. 482 NEW YORK STATE MUSEUM up a large proportion of the rock at Graphite, while on Bear Pond mountain they are entirely absent. Whereas the Graphite occur- rence is massive, the Bear Pond mountain variety consists of thin layers interbedded with sandy quartzite. There has been much shearing and crumpling, and the whole series is impregnated with iron oxids. The bedded nature of this sillimanite gneiss is certain. At Graphite, limestone has been found in a prospect boring, beneath the sillimanite gneiss. At Bear Pond mountain the silli- manite gneiss overlies the hornblende gneiss, no limestone being present. These relations suggest the possibility of an unconformity between the sillimanite gneiss and the limestone series, although the limestone is so patchy in its general distribution as to prevent too confident drawing of conclusions. The graphitic sandstone occurs in a small area about North pond. It is a gray variety, weathering red, dipping steeply west, and containing abundant flakes of graphite and of mica. On the north- east bay of Rock pond a small mine has been opened. The graphite occurs along a fault line, associated with iron pyrites. Slickensides are abundant in the opening. The country rock is the above described quartzose gneiss, of probably sedimentary origin. The biotite schist, commonly interbedded with the limestone, appears near the mine. The sillimanite gneiss is present on the neighboring mountain. The strike of the graphitic sandstone is n. 5 e., its dip 70 W. The sandstone is similar to the layer bearing the graphite at the mine of Graphite. The chief difference is that whereas at the Graphite exposure flakes of graphite form the principal constituent of the rock and the only scaly constituent, at North pond mica is also present. The North pond rock is hence less valuable econom- - ically, since it not only contains a smaller percentage of graphite, but the process of concentration would be complicated by the presence of two scaly minerals. Both rocks contain much accessory pyrite, and weather yellow or red. 3 Geologically the two rocks probably represent the same formation, and both are intimately related to the sillimanite gneiss. The silli- Plate 11 Penfield limestone belt with interbedded schist GEOLOGY OF THE PARADOX LAKE QUADRANGLE 483 manite gneiss represents shale, and the graphitic rock the sandstone of the same series. Shaly quartzite. Overlying the garnet-sillimanite gneiss of Graph- ite is a quartzite, impure and feldspathic, in some localities sheared into a schist. It occurs also in the bed of the brook at the extreme southeastern corner of the quadrangle. Several fault lines can be seen along the brook, the most notable one being at the Hague gristmill [see pl. 8, fig. 1]. The exposure at the graphite mine in the village of Graphite is. separated from an eastern one at the Lakeside mine, Hague, by a hill of syenitic gneiss and by drift in the valley. The uniform strike for both localities is n. 65 e. and the dip of variable amount, toward the southeast. The eastern exposure would hence appear to be the upper one, but the frequency of faults makes its position uncertain. Some layers at the extreme eastern edge of the map are conglomeratic. Summary of stratigraphic relations. The oldest rock is the horn- blende gneiss ; conformably above this is limestone ; interbedded with both is the biotite schist. Above these, possibly with an uncon- formity, is the sillimanite gneiss; interbedded with it as a local variation is shaly quartzite; above these, graphitic sandstone. Intrusives. It has long been recognized that the core of the Adirondacks consisted of a rock of the gabbro family which has been named anorthosite. It has also been long recognized that gabbros of later age than the anorthosite were widespread. Of late years another type of intrusive has been recognized by Dr Smyth on the west and by Prof. Cushing on the north, and has since been found throughout the region, the most common phase of this rock being a syenitic one. All of the above types occur in the Paradox Lake quadrangle. A fourth variety which has not yet been recognized as a distinct type, although phases of it have been described, is also present in large amount in this quadrangle. This will be here called the Pharaoh type from the mountain where it is best exhib- ited. It presents the general mineralogy of a granite, but appears to be a different rock and older than the granite found in the’ 484 NEW YORK STATE MUSEUM northern and western Adirondacks. ‘The anorthosite, syenite and granite are all characterized by sudden and very great variations in the distribution of the ferro-magnesian constituents. [hese con- stituents may be gathered together, giving the rock locally the ap- pearance of a gabbro, or they may be wanting altogether, giving in the case of the anorthosite a pure plagioclase rock, in the case of the syenite a plagioclase, orthoclase and microperthite rock, and in the case of the granite an orthoclase, quartz, microperthite rock. The basic varieties are the confusing ones, for with increasing ferro- magnesian constituents the three types approach each other very closely. Later than all three is the typical gabbro. All .are plutonic and younger than the sediments. : Granite. Granitic rocks form a considerable area in the south- west, including Pharaoh mountain and. several unnamed peaks of some importance. The rock, usually pink in color, is a hornblende granite, but sometimes contains considerable quantities of biotite. It is frequently gneissic, the granite gneiss sometimes being hard to distinguish from the syenite gneiss and. the gabbro-gneiss. alte igneous gneisses may readily be separated from the sedimentary ones by their massive character and by their uniform appearance Over wide areas. | That this granite is later than a intruded into the limestone series is indicated by numerous pegmatite dikes and bosses. In passing from Mount Pharaoh to Mount Treadway one traverses first coarse granite dikes, then pegmatites, and finally to the east of Treadway, quartz veins. This is strongly suggestive of the natural and normal relations which so often occur around intrusives. _ Syenite. Rocks of this type are proving to be one of the com- monest of Adirondack intrusives. ‘The type was first described by Dr Smyth, and has since been found in many localities, proving to be an extensive component of the gneissic areas. The occurrence in the Paradox [cakes uadrangle i is in all respects similar to those already described. Smyth ©) te qe Geol. Soc. Amer. Bul. 6: 271-274; N. Y. State Geol. 17th An. Rept 1899. p.471-486. Cushing, H. P. Geol. Soc. Amer. Bul. 10:177-192; N. Y. State Geol. 18th An. Rept 1899. p.105-1009. Plate 12 Towner pond. Recrystallization of limestone, accompanying twisting of interbedded schist GEOLOGY OF THE PARADOX LAKE QUADRANGLE . 485 The typical appearance of the rock is massive, with a dark green color. It has a tendency to weather far below the surface, and when weathered the color changes to yellow or brown. ‘It is often of pneissic structure, and when this is the case the color often becomes a dark gray. As shown on the map, the syenite occurs in several isolated areas, the largest being in the northeast. Another smaller area is on the easterm shore of Schroon lake, where syenite and granite grade into each other without perceptible contact. In the southeastern syenite area, on the mountain 1913 feet high, locally called Trumbull (not the Trumbull of the map) there occurs an interesting exposure of sedimentary gneiss in the midst of syenite. It forms a small eastern spur of the mountain and is too large to be a fragment torn off by the intrusion. It must represent an area of the sediment yet in place, at the top of the intrusion and sur- rounded by it. | Anorthosite. As shown on the map, there is a large area of anorthosite ini the northwestern part of the quadrangle. This area marks the southern and eastern extension of the intrusion which forms the main mass of the highest mountains in the Marcy region. The topography of this section is more rugged, with higher moun- ‘ tains and deeper valleys than the surrounding areas of gneiss, this difference being probably not due to greater hardness in the rock but to two dome-shaped uplifts. 6 The name “anorthosite” has been Often erroneously criticized because of a supposed mistake in the first determination of the feld- Spar. It was not named from anorthite, but from “ anorthose,” which was an early French name for all triclinic feldspars as opposed ‘6 b to “ orthose,” for all monoclinic ones. Hence ‘‘ anorthosite ’’ means literally ‘“ plagioclase rock.” 3 | . The anorthosite is typically a coarse grained rock of bluish or greenish color containing large irridescent crystals of labradorite. The dark silicates are usually gathered together in bunches, the pre- vailing rock consisting of feldspar only. About the border of the anorthosite area the rock is gneissic. As already mentioned, the 486 NEW YORK STATE MUSEUM anorthosite area occupies a central position in the Adirondacks. The area within the Paradox Lake quadrangle comprises a segment of the outer portion of the intrusion, and in it a series of meta- morphic changes are evident. These will be described in part 4, on petrography. The anorthosite forms the highest and most rugged mountains in the quadrangle. Gabbro. In a few small patches gabbro rocks occur—true gab- bro, norite, and hornblende gabbro (meta-gabbro). The most im- - portant exposure is on Peaked hill. The gabbro is typically a medium grained rock, of greenish black color. The dark color serves to separate the rock from the anor- thosite and syenite. | Several dikes of the gabbro are found. On the southern shore of Pharaoh lake a gabbro dike cuts gneiss; on Bull Rock mountain (called Old Fort on the map) a gabbro dike cuts the syenite; two dikes southwest of Chilson cut graphitic sandstone; one dike about a mile west of Chilson cuts sedimentary gneiss; on Moose moun- tain a very basic gabbro dike cuts anorthosite. The gabbros can in many localities be traced directly into horn- blende schists, or amphibolites, and there is no doubt that many dikes of these gabbros exist. But in some localities, as on Ellis mountain in Hague, dikes are exposed which are purely schistose, with no trace of massive facies. It becomes a matter of some difh- culty to determine whether such dikes belong to the syenite in- trusion, or to the gabbro, or whether they*represent a distinct intrusion in themselves. It is upon the age of these dikes that the relative ages of the syenite and granite depends. The granite is frequently cut by dikes of hornblende schist ; if these could be proved to belong to the syenite the relative age would be established. In the localities on the south shore of Pharaoh lake and on the moun- tain west of Goose pond these schists occur, grading directly into massive gabbros. In the last-mentioned locality are a series of dikes ~of pure schist, precisely like these questionable ones which so fre- quently cut the Pharaoh gneiss, but fortunately in one a massive facies was found which placed this set with the gabbros. It is GEOLOGY OF THE PARADOX LAKE QUADRANGLE 487 therefore probable that most of the dikes belong with the gabbro. Nevertheless some of the basic portions of the syenite mass present the mineralogy of a gabbro, and if .sheared .would pass into -amphibolites. Summary of evidence of relative age of igneous rocks The anorthosite is cut by gabbro at Johnson pond and on Moose mountain ; the syenite is cut by dikes of gabbro on Bull Rock moun- tain (called Old Fort on the map), at Chilson, and at the foot of Cat mountain. j an g The relation between syenite and anorthosite is doubtful, no con- tacts between the two having been found. Dikes, possibly of syenite, cut anorthosite on Blue Ridge mountain. - The relation between syenite and granite is also doubtful, the two types often appearing to grade into each other. The granite is cut by dikes of amphibolite; some of these appear to belong with the gabbro; others are altogether doubtful and may belong in age with the syenite. | Gabbro is thus the youngest in age; anorthosite, syenite and granite are undoubtedly of nearly the same age and derived from the same source since they present gradations towards each other. Anorthosite, syenite, granite, is the most probable order of intrusion. Pegmatites. The origin of pegmatites has furnished occasion for much discussion in the past. The close relations of pegmatites to igneous rocks and their occurrence as dikes have led many observers to regard them as true intrusives. On the other hand, their coarse structure and frequent association with quartz veins have led others to the reverse view, namely, that solution was too prominent in their production to admit of an igneous origin; that they are essentially veins, and that they are genetically related. to igneous rocks, with more or less of pneumatolytic action at their time of consolidation. In the northeastern corner of the quadrangle, in the neighborhood of Towner pond, there is limestone in close proximity to intrusive syenite and granite. Contact effects are to be seen in the presence of enormous pegmatites. Roe’s spar bed is a famous locality for 488 ; NEW YORK STATE MUSEUM minerals! and is a huge pegmatite which has been opened for the economic value of the orthoclase in the manufacture of porcelain. Crystals of biotite, orthoclase and quartz, sometimes over a foot in length, occur at this quarry. Three small diabase dikes cut it, along which are developed tourmaline and titanite. There are several _ good sized hills consisting of pegmatite in this locality, with smaller pegmatites cutting sedimentary gneiss. This famous pegmatite can be followed towards the tae intrusion, with increasing biotite as the granite is approached. When followed away from the granite the pegmatite becomes more acid and contains much graphic granite. Small dikes of pegmatite border the mass around the spar bed, these dikes being more acid than the larger ones. Beyond the dikes are veins of rose quartz. Many pegmatites border the granite of Mount Pharaoh. In this case small dikes only were found. Those near Mount Pharaoh presented the general mineralogy of a granitite, usually with acces- sory tourmaline or titanite; the more remote ones contained fewer dark silicates. Pegmatites also occur about the edge of the anorthosite area. These pegmatites contain the same bisilicates as the anorthosite, with quartz, orthoclase and magnetite also. There seems no doubt that these pegmatites belong to the closing stages of the intrusions ; and that they are of igneous origin, but were produced with-the aid of more water than their associated plutonics. On the hills about Crane pond pegmatites are particularly abun- dant near the limestone contacts, while quartz veins predominate in the quartzose gneiss area. There are complete gradations between the two, though any connection with plutonic sources is here cut off by faults. Professor Van Hise has pointed out? that the true explan- — ation of pegmatization includes igneous injection, aqueo-igneous *Roe’s spar bed has been referred to in the following papers: E. H. Williams, Am. Jour. Sc. 1881, on tourmaline; J. F. Kemp, Am. Jour. Sc. 1888, on minerals near Port Henry; J. F. Kemp on Geology of Crown Point, N. Y. N. Y. State Geol. An. Rept for 1893; J. F. Kemp, U. S. Geol. Survey Bul. 107, on Trap Dikes of Lake Champlain. f >C. R. Van Hise. Principles of Precambrian Geology. U.S. G. S. 16th An, Rept ptr. p.684-687. 4 Plate 13 Faulted dikes, Pharaoh lake GEOLOGY OF THE PARADOX LAKE QUADRANGLE 489 action, and water cementation ; that there are all gradations between the three processes, and that under conditions of high temperature and great pressure, water and magma are miscible in all proportions. It would therefore follow that as a center of intrusion was left, the more volatile constituents of the intrusion would be deposited radi- ally and at the same time percolating superheated ground water, containing in solution various constituents from the wall rock, would become mingled with the plutonic material. There would therefore be a gradation between injection processes and cementation. These old gneisses seem sometimes to have undergone further cementation with no connection with intrusions. Quartz lenses are frequent in the quartzose gneiss, and so is secondary quartz in micro- scopic quantities. These occurrences belong to the process of cementation of the rock by infiltration of silica in solution. This cementation may have been a continuous process from the time of the first intrusion, but its greatest development must have been sub- sequent to the main intrusion, for the reason that the intrusions were all too deep seated to be in the zone where percolating water could have had much, if any, effect. In résumé it may be stated that the plutonics were intruded at great depths, some pegmatites being contemporaneously developed at their periphery. The gradual migration to the surface, through the removal by erosion of the overlying burden, gave increasing opportunity for the action of percolating ground water, and the exact line at which the boundary is to be drawn between dike and vein, or between vein and secondary crevice filling or enlargement of original grains, can not be sharply established. Dikes. Trap dikes have been noted in several localities. The dikes on Pharaoh lake have already been described in the report previously referred to. They are of diabase, and form an anasto- mosing network running across the strike of the gneiss. These dikes cut: pegmatites. They have been more readily weathered than the surrounding eneiss [see pl. 10]. | There is another diabase dike ‘on the north side of Treadway mountain. It outcrops on the face of a small cliff. 49C NEW YORK STATE MUSEUM At Roe’s spar bed, one mile south of Towner pond, three diabase dikes cut the huge pegmatite exposure. One occurs near Fleming pond, one mile south of Hammondville ; another in the gneiss a mile northwest of Penfield pond. Acid dikes of the type known as Bostonite were found in two localities: one at Heart pond, the other north of Worcester pond. These dikes are bright red and are very small. Palaeozoic formations. Potsdam sandstone. As shown on the map, the Potsdam occurs in three localities. Of these the Chilson area is the most important. There are three good outcrops in this area. On the hill near the gabbro are ledges of yellowish quartzite, and not far away in the fields are several small outcrops of con- glomerate. The conglomerate and reddish sandstone represent the basal Potsdam. Farther east in the brook is an exposure showing the contact with gneiss. This also is the reddish lower facies. To the south on the road to Putnam pond is an outcrop of a gray color, which represents the upper facies and is slightly calcareous, showing a gradation towards the Calciferous. These exposures all rest unconformably upon the quartzose gneiss, and the conglomerate contains pebbles of the same gneiss. The Crown Point area of Potsdam sandstone is a small remnant of the reddish yellow type. It has the usual strike of n. 10 e. and dip of 10 n. w. A pretty little postglacial canyon, with some ‘cascades, is to be seen where the north branch of Putnam creek crosses this Potsdam area. Many loose boulders of Potsdam sand- stone and of Calciferous, Chazy and Trenton are scattered about . the fields near this locality. These rocks are not glaciated but indi- cate the former presence of these formations in the valleys. 7 The exposure on Trout brook shows interesting cutting of the stream channel laterally down the dip, with resulting cliffs on the down-dip side. The rock is the reddish variety, with a strike of n. 20 e. and a dip of 15 n. w. : Trenton limestone. In a cut of the abandoned railroad, about a mile west of Ironville, are a series of small exposures of dark gray limestone, containing typical Trenton fossils. A steep and very variable dip, with some variation in strike, points to the possibility Plate 14 Faulted dikes, Schroon lake GEOLOGY OF THE PARADOX LAKE, QUADRANGLE 491 that these rocks were not in place, but since they showed no sign of glaciation they were regarded as probably representing an erosion remnant. An interesting sheared zone was observed in one of these exposures. A strip about an inch wide had been slickensided and completely recrystallized, the many fossils of the side walls com- pletely disappearing. The sheared zone consisted of pure calcite, polysynthetically twinned. The following fossils were identified from this locality : Trinucleus concentricus Calymmene senaria Ceraurus pleurexanthemus (Green) Bathyurus (?——) Protowarthia cancellata Dalmanella testudinaria | : Glossina trentonensis (Lingula attenuata Conrad, L. rectilater- alis Emmons ) Platystrophia biforata Faults. Dislocations of varying magnitude are very widespread. As no stratigraphy can be made out the amount of displacement can not be ascertained, nor is the age always capable of deter- mination. A prominent fault cliff extending some five miles in a n. 15 e. direction from Knob mountain has already been noted by Professor Kemp. The breccia of this fault is displayed in a cut of the abandoned railroad. As fine a scarp extends in the same general direction southwards from Bear mountain. There is a gen- eral parallelism among the various sets of faults in their general directions, but they often curve through a considerable angle. These northeast-southwest scarps are much the freshest and are probably the latest. ae The northwest-bearing fault along the base of Treadway moun- tain is interesting in that its breccia showed infiltrations of iron oxids bearing pyrite and scales of graphite. The graphite was mere undoubtedly formed by a secondary deposition, but was prob- ibly derived from the limestone or sandstone. Another set of | faults strikes eastwest. 492 NEW YORK STATE MUSEUM - The numerous faults are outlined on the map. Their presence is. usually indicated by a cliff, but some of the older ones have weathered so as to be recognizable only from a crushed strip. Many of these may have been overlooked in consequence of the dense vegetation and lack of paths or of outlook. Shear zones. About three miles west of Graphite are three par- allel gorges with an east-west direction, the largest of which is locally known as the “Ice gorge.” These three gorges are estab- lished along three shear-zones. The nearly perpendicular cliffs of the ice gorge are about 500 feet high, while those of the smaller gorges are about 200. The country rock is a porphyritic gneiss, _with large orthoclase phenocrysts in a quartzose ground mass, and containing much biotite. The rock from the sheared zones presents a granulation of constituents with an infiltration of iron oxids. Small faults and shear zones are of almost universal occurrence in this region and traverse all types of rock. | : Foliation. This structure is common to all the Precambric rocks, and the general direction of strike is similar. A direction of n. 40 e. is the prevailing one, with low southeast dips. Since the direction of foliation is common to all the rocks, it must have a common origin; since no relation is shown between direction of foliation and any of the intrusives, the structure can not be due to igneous agencies. It appears to result from a thrust from the southeast, while the rocks were still deeply buried. A similar and later thrust when they were nearer the surface appears to be the cause of the faults. Joints. The Precambric rocks are extensively jointed, the joint planes running in all directions. The joints are usually vertical and as a rule only two sets, nearly at right angles to each other, are present. Occasionally a third, highly inclined joint is present. Their directions are too inconstant to be reduced to any system. | PART 4 Bis Petrography It was found difficult to distinguish. macroscopically among the 4 basic phases of the three intrusive types—anorthosite, syenite and granite—since with increasing ferro-magnesian minerals they ap- = ye be 2 ee FKP Dee wl. Plate 15 Fig. 1 Gooseneck pond; a faulted rock basin s Fig. 2 Gooseneck pond; a faulted rock basin GEOLOGY OF THE: PARADOX LAKE QUADRANGLE 493 proach each other.: -They also-approach very closely. to: the fourth intrusive type, namely, the gabbro.. It was possible, however, to trace these basic developments into: masses typical of the classes to which they belonged, and with microscopic work the: distinctions became clearer. On the map the areas were colored according to their genetic relationship and they were named according to the most prominent type of a single formation. The map is therefore not lithologically accurate, since rocks that could properly be named gabbro, or diorite, are included within -both syenitic and granitic areas. Only those were mapped as gabbro which could be recog- nized as distinct in age from the other three intrusions. | The relationships are further complicated by the intense meta- morphism, all four types frequently being gneissic. The granitic gneiss approaches the syenitic gneiss on the one hand, the sedi- mentary hornblende gneiss on the other, while anorthosite gneiss often resembles syenite gneiss or gabbro gneiss. Hence the only possibility of unraveling their relationships is by studying them over wide areas. , The difficulty is further increased in that preglacial valleys were usually established along the contacts, these contacts now being masked: by drift and swamp. The boundaries on the map are therefore subject to some doubt; in some cases several miles of swamp occupy the contact, in others gneisses appear to belong with almost equal accuracy to either of two types.. But although the boundaries may be a matter of dispute, it is confidently believed that the high mountains in the northwest consist of anorthosite; that these are bordered on the east and south by a sedimentary belt; that Pharaoh: mountain marks the central part of a granite intrusion, and that the mountains-of the southwest consist of the syenite. Petrography of sedimentary rocks Farablende gneiss. As before stated, this rock is; ‘extremely vari- able in mineral composition. . Streaks of. biotite, schist. are inter- bedded with it; granite, syenite, anorthosite, pegmatites and trap cut it. The country, rock itself is. variable in composition, . and has 494 NEW YORK STATE MUSEUM been highly metamorphosed and recrystallized. Thin sections of this rock from Mount Treadway exhibit quartz, feldspar, hornblende, | biotite, piedmontite, magnetite and ilmenite. There is every evi- dence of intense metamorphism. ‘The quartz is strained, with undu- latory extinction. The feldspar is mainly microcline, with sub- ordinate plagioclase, and both feldspars show strain effects. Anor- thoclase is often present. The plagioclase is usually oligoclase, but both albite and labradorite are sometimes found. Large pink garnets are sometimes present. The biotite is a very black variety, pleochroic from black to pale brown, and often exhibiting pleochroic halos. The piedmontite is small in amount, but is present in nearly all the slides examined of this type of rock. Considerable variation in the amount of metamorphism is to be seen in this series, and some variation in the relative quantities of constituents. On Third Brother the maximum of strain is reached ; some of the feldspars are bent through a large angle, and all feld- spar and quartz show undulatory extinction. Mlicrocline is the pre- dominating feldspar. Piedmontite is abundant. Several brecciated zones were found on the sides of the mountain and near its top; — at first sight they resembled serpentine dikes, but closer study showed them to be small shear zones. These fault breccias showed pre- vailing secondary minerals, quartz, epidote, chlorite and related minerals. Faint traces of hornblende were made out, nearly altered to chlorite with finely divided epidote and calcite. The plagioclase was completely altered to kaolin and saussurite. Some magnetite is present. Precisely similar rock occurs northwest of Penfield pond, and on the hill northeast of Paradox lake. The commonest type is somewhat less strained, with hornblende and biotite in about equal amounts, and with microcline, plagioclase and orthoclase in decreasing order of abundance. Quartz is always the most common mineral. On the mountain erroneously called Trumbull on the map (the local name is Ellis) is found the least altered variety of this rock. No microcline was present, but a larger proportion of orthoclase altering to kaolin and zeolites. The quartz was less strained; the biotites showed no halos; no piedmontite was found. GEOLOGY OF THE PARADOX LAKE QUADRANGLE 495 The quartz usually constitutes about 40% of the rock; feldspar - over 50%; the remaining dark silicates being thus small in quantity. - Unfortunately the rock was invariably too greatly weathered for an analysis to be accurate, but it is confidently believed that if such an analysis could be made the silica content would be high enough to place the rock without doubt among the sediments. The biotite schist which forms bands in this gneiss and in the limestone is found to contain large quantities of quartz. Quartz forms from 20% to 30% of the rock and biotite is present in about the same amount. The remainder of the rock is made up of feldspars (microcline, albite, labradorite and oligoclase all being found, usually one variety predominating and one other being less in amount), garnet, zircon, apatite, and magnetite, in varying proportions. The probability concerning this gneiss is that it represents the base of the Grenville series, which has suffered from the meta- morphism common to the region as a whole, and which has experi- enced in addition an excessive amount of recrystallization and squeezing from being nearest to the intrusives. Sillimanite gneiss. Thin sections of the rock at Graphite show large garnets embedded in a mass of fibrous sillimanite. The silli- manite crystals show a roughly parallel arrangement. A little quartz is present and accessory zircon, pyrite and graphite. The foot and hanging wall are similar, except that the foot wall contains microperthite in addition to the minerals found in the hanging wall. The sillimanite gneiss from Bear Pond mountain contains similar shreds of sillimanite. Biotite is present in large quantities, the biotite being younger than the sillimanite. In the prevailing type shreds of biotite and of sillimanite are arranged in parallel groups, the terminal faces of both being lacking. Occasionally a sillimanite crystal is found cutting across the biotite at right angles to its long axis, and in such cases it is the sillimanite that has the perfect boun- dary. Accessory pyrite and rutile are sometimes present. Petrography of the igneous rocks Of the four types of igneous crystalline rocks found on the Para- dox Lake quadrangle—granite, syenite, anorthosite, and gabbro— 496 J 142) NEW: YORK. STATE MUSEUM only two, the anorthosite and.gabbro, were recognized: as intrusives in the preliminary: report on the region: The granite and syenite together constituted a “‘ doubtful.” area which was, for convenience, | called “ Series I,’’ the presumption being that they were older than the limestone and possibly: to. be correlated with the Ottawa gneiss of Canada. ie : Granite. The granite of the Paradox Lake quadrangle is usually gneissic. . It is believed to be igneous because of its constant composition over wide areas; it is regarded as intrusive into and younger than the sedimentary hornblende gneiss because of the small dikes and pegmatites which appear to radiate from the granite, cutting the sedimentary gneiss. In no case could a true intrusive contact be found. In most localities where the two gneisses come together, or where the massive granite gneiss is in contact with the limestone, faulting is found to be the cause. Where there is no fault in evidence, the contact is obscured by swamps. In mineralogy this granite-gneiss is very constant. It contains hornblende, orthoclase, plagioclase and quartz, with occasional acces- sory biotite, muscovite, magnetite, pyroxene, apatite and zircon. Some slides of this rock present the normal appearance of a horn- blende granite, but usually the minerals are drawn out into gneissic bands, the orthoclase changed to microcline; the quartz showing undulatory extinction ; the hornblende bent and twisted but unaltered optically. Tiny shear zones are common, filled with secondary quartz, chlorite or zeolites. Secondary garnets are occasionally present, but are not so common as in the more basic rocks. Inter- growths of quartz and orthoclase (micro-perthite) are common. _ Another variety is porphyritic, with phenocrysts of orthoclase. Still another variety is that which contains the Hammondville ores. This type is conspicuous in the absence of ferro-magnesian minerals, consisting mainly of quartz, microperthite and. plagioclase. A scattering of magnetite ‘grains with very tare hornblende are present as slight accessories. The hornblende 1s usually brown. Occasionally the Sag! variety is found. | — SSIOUS BJIULIN) ‘puod sueI>D WOIf ‘Youley_ IN OT 248ld GEOLOGY OF THE PARADOX LAKE QUADRANGLE "497 The quartz sometimes occurs in grains, but more often, especially in the crushed varieties, in lenses. Evidently in some cases the quartz has been enriched secondarily. . The structure is frequently cataclastic, the constituents appearing to be in grains resulting from the crushing of larger crystals. The rocks possessing this structure pass by insensible gradations into true granites, and there can be little doubt that the gneisses exhibit- ing this structure are crushed portions of the granite. | The rock found in Pharaoh mountain is the most wide-spread type. It presents a general pink appearance in the hand specimen, and under the microscope proves to be a hornblende-granite-gneiss. The Pharaoh type contains about 50% of feldspar. Predominating orthoclase, with accessory albite or oligoclase, is probably the normal composition, but these have usually been replaced by microcline and imicroperthite. Primary quartz constitutes about 30% of the rock, although the actual quartz content is almost always increased by the presence of secondary lenses and veinlets. The remaining 20% is made up of hornblende and the accessory minerals. Syenite. As already mentioned, the syenite of the Paradox region belongs to the syenite type of Cushing and of Smyth. The preliminary reports on the Paradox region were published before this type was recognized, and it was included within the “ doubtful ” area. | In thin section a cataclastic structure is commonly found. There is much variation in mineral contents, there being a complete grada- tion from an augite syenite containing microperthite to a type closely resembling the granite and consisting essentially of hornblende, microperthite, subordinate augite, quartz and a little biotite. There is constant likeness between this type and the granite of Mount Pharaoh in the presence of intergrowths of several different min- -erals. Microperthite (consisting of intergrowths of orthoclase and albite) is a normal component, and less frequently there occurs (in the syenite only) an intergrowth of green augite with bronzite or hypersthene. Quartz is usually present in the syenite, and its often elongated lens-like form suggests that it is secondary. Some primary quartz is present also. The pyroxene is a bright emerald green variety. 498 NEW YORK STATE MUSEUM The syenite from the southeastern area contains as essential min- erals microperthite, a deep green nonpleochroic augite, small amounts of hornblende and of quartz, with_accessory apatite, mag- netite, zircon and garnet, the last named perhaps secondary. The syenite from the area on the eastern shore of Schroon lake contains relatively more hornblende and more quartz. In the Crown Point area labradorite is present in addition to microperthite. | Within the anorthosite area of the Blue Ridge, about a mile from the boundary of the syenite, are three dikes which cut the anorthosite. These dikes contain green augite, labradorite, and very abundant garnet. They appear to belong with the syenite intrusion, and if so, would indicate that the syenite is younger than the anorthosite. Anorthosite. Anorthosite is a coarse grained rock of the gabbro family, presenting the extreme of the series rich in feldspar. Somte occurrences consist of pure plagioclase. 3 : In its massive phases the rock is quite fresh. The plagioclase is twinned according to both pericline and albite laws. It is always labradorite. Hypersthene, pleochroic from pink to green, and a pale green, normal augite are the only other minerals which occur in appreciable quantities. The structure is irregular, the bisilicates being grouped together and not evenly distributed through the rock. Associated with the grouping of constituents is a variation in size of grain. When crushed, the dark patches are pulled out into len- ticles, or into gneissoid banding. Similar sudden variations in tex- ture have been noted by Professor G. H. Williams, in the Baltimore | gabbros.! ; Hornblende, biotite and orthoclase may be present in small quan- tities, with accessory or secondary magnetite, titanite, ilmenite, apa- tite, chlorite, epidote, garnet, zircon and spinel. An extensive series of metamorphic effects can be seen. In the northwestern portion of the quadrangle the rock is uniformly mas- sive, except when brecciated by faulting. The labradorite crystals *G. H. Williams. “The Gabbros and Associated Hornblende Rocks Occur- ring in the Neighborhood of Baltimore, Maryland.” U.S. G. S. Bul. 28. GEOLOGY OF THE PARADOX LAKE QUADRANGLE 499 show their characteristic irridescence and are an inch or more in length. Farther south and east, along a zone beginning a few miles _from the border of the intrusion, the rock is granulated and a cata- clastic structure is seen in thin section. If present, the bisilicates are drawn out into irregular bands. If slightly more crushed the rock becomes a gneiss, and as the granulated labradorite is white, it becomes a matter of some difficulty to distinguish in hand specimens between gneissic anorthosite and the sedimentary gneiss. It was this banding which led Emmons to claim a sedimentary origin for the rock. The extreme of metamorphism is seen in a complete mashing and the development of new minerals. On the hill north- west of Paradox lake is a variety which in the hand specimen is an even white color, with no constituent minerals distinguishable, and with large secondary garnets embedded in the white mass. In thin section this white rock is found to consist of broken pieces of plagio- clase, and in general the whiter the rock the more complete the granulation. The completely granulated rock resembles a massive limestone. If ferro-magnesian minerals are present they may be drawn out into gneissic bands with a cataclastic structure. Garnet, secondary after pyroxene, often occurs. These intensely granulated anorthosites frequently contain titaniferous iron ore. Prof. Frank D. Adams' has suggested that these ore bodies may be due to a gathering together, from crushing, of minute inclusions previously contained in the feldspar. The area in Canada which he describes is remarkably similar to the one under consideration, but the Adiron- dack area does not contain such an extensive amount of black dust in its labradorite. Titaniferous magnetite occurs in occasional crys- tals in the massive anorthosite, and its formation appears to be that of a local gathering together of constituents analogous to that of the grouping of the bisilicates. The dark silicates are more abundant in the peripheral portion of the intrusion. The irregularities in size of grain and in distribution of constitu- ents mist be due to processes taking place during consolidation. Whether the processes are chemical in their nature or physical, or *F. D. Adams. Geol. Survey of Canada; Rept: J. 1805. v.8. 500 aes NEW “YORIC) SPADE MU SHUMes ata whether -varying specific gravity ofthe minerals isa factor in their localization-is yet to be:demonstrated. The granulation of the mas- sive rock and the gneissic banding are undoubtedly secondary effects, having taken place after the consolidation of the rock as a result of pressure. Garnet is the only undoubtedly secondary mineral present except those which are subsequently caused by a local shear. The occur- rence of such intense granulation without a corresponding change in ‘mineralogy (augite to hornblende or uralite, feldspar to saussurite and albite, etc.) is unusual. Prof. Frank D. Adams, in the report already cited, suggests that movement must have taken place while the rock was deeply buried and at a high temperature. The deep burying accounts for the ahsence of shearing effects; the high tem- perature for the lack of secondary hornblende, which needs low temperature for its production. ‘The Adirondack occurrence is pre- cisely similar to the Canadian one here described. — Gabbro. The gabbro proper is a basic variety, consisting of lab- radorite, green monoclinic augite, titanite, sometimes hypersthene and occasionally olivine. It usually presents an ophitic texture, with broad laths of feldspar which have the ferro-magnesian constituents between them. With increasing hypersthene the gabbros pass into norites; with increasing ilmenite and titaniferous magnetite the gabbro passes into the titaniferous iron ores. 3 The anorthosite and gabbro illustrate the familiar truth that basic rocks are more liable to vary than acid ones. The gabbro family appears to be particularly variable, as is evident from a comparison of the mineralogy of the various types. The gradation from a pure labradorite rock on the one hand to a titaniferous iron ore on the other is a much greater change mineralogically and chemically than is ever known in so small an area among granitic rocks. The gabbro area near Johnson pond presents a series of grada- tions from a dark garnetiferous gabbro to a labradorite rich variety, which is practically a pyroxenic anorthosite. In the northern part of this area the more typical gabbro ‘occurs, and its contact with the anorthosite is distinct and suggestive of an intrusion of the gabbro into the anorthosite. In the southern part, however, on Peaked hill, ‘GEOLOGY .OF THE PARADOX. LAKE QUADRANGLE 50OI there is considerable confusion, gabbroic:.bands alternating with anorthosite in an astonishing manner. The southern and eastern boundary of the area was difficult to determine because of this alter- nation and gradation of types. In the extreme eastern portion of the area mapped as gabbro there is a rock which seems to repre- sent crushed gabbro. It consists of garnet, of almost. microscopic size, which gives the rock in the hand specimen the appearance of a granular ageregate of little garnets. The same rock is found ina series of dikes on top of the mountain 1742 feet high, slightly north of east of Peaked hill. ¢ In thin section the. garnet rock i is saa to be a true gabbro, con- taining green pyroxene, labradorite, diallage,.titaniferous magnetite and garnet. These small dikes differ from the commoner bosses in being of finer grain; in having relatively ereater abundance of garnets, and in the presence of diallage. _ The occurrence of the small garnetiferous dikes in the anorthosite, and also along the contacts of gabbro and anorthosite, suggests their peculiar structure as due to contact effects. They are certainly a part of the gabbro intrusion, and their occurrence indicates that the gabbro is later than the anorthosite. The gabbros are usually crushed, and then develop! eneisses which can not be distinguished from the gneissic development of the gabbro phase of the anorthosite, nor from the gabbroic part of the syenite, nor from some areas found among the granites. The gabbros are frequently granulated and show gradations sim- ilar to those seen in the anorthosite. There appears also to have been recrystallization in the gabbros. ‘The plagioclase contains many fine black inclusions. which may be either pyroxene or titaniferous magnetite, or both. They are apparently inclusions, not alteration products. Similar inclusions have been described by many writers on gabbros.t Reaction rims are common. Geeky Walliams. U.S. GS. Bul. 28. F. D. Adams. Uber das Norian oder Ober- Taurentian von Canada. Neues Jahrbuch. Band 8, p.425. 'A. C. Lawson. Anorthosites of the Minn. Coast of Lake Superior. Minn. Geol. Survey Bul. 8. 1893. p.8. - : J. F. Kemp. Gabbros on the Western Shore of Tales Gres Bul. Geol. Soc. Am. 5:213-24. é 502 NEW YORK STATE MUSEUM Summary and conclusions The investigation of the gneissic area resulted in showing the b) possibility of splitting up the “doubtful gneiss” of earlier reports into three types: (1) Syenite, which is igneous in origin and is in all respects similar to the syenite previously described in other Adiron- dack localities. (2) Granite. (3) Quartzose gneiss of sedimentary origin, which may be the rock that has sometimes been termed “gneiss of the limestone series.” The syenite is without doubt a plutonic igneous rock, and although gneissic phases are common, completely massive ones predominate. The granite is more com- pletely gneissic, and for that reason there is less certainty in deter- mining it. Both syenite and granite are alike in presenting varia- tions in the percentages of ferro-magnesian constituents. The third type of gneiss is the most highly metamorphosed. It contains so many intrusions of small size both of syenite and of granite that it was found impossible to mark them off in mapping. It was further altered by secondary infiltration of quartz, both in the form of large veins and of disseminations of microscopic size. The presence of these small intrusions affords evidence that the granite and syenite are younger than the quartzose gneiss; and the character of the rock, its macroscopic and its microscopic appear- ance, and the topography of its mountains point toward a sedi- mentary origin. Its frequent association with the limestone (occur- ring sometimes in thin layers folded with the limestone, sometimes in hills while the limestone occupies the intervening valleys) points toward the conclusion that this quartzose gneiss is a member of the limestone series. Since this gneiss underlies the limestone, and also underlies the other gneisses which are of sedimentary origin, it is thought to represent the base of the Grenville series. In its basal position is to be found the explanation of the great number of intrusive masses which render this rock so difficult of interpretation in the field. Being at the bottom of the sediments, it formed'the por- tion most subject to alteration from the intrusions, and it now con- tains within its mass remnants of what were apophyses from the top of the intrusions. GEOLOGY OF THE PARADOX LAKE QUADRANGLE 503 Of the relative ages of the intrusives, the only evidence is that of somewhat doubtful dikes. Some of the dikes. are undoubtedly gabbro and cut all the other Precambric intrusives; others may be syenites and cut anorthosite, and possibly granite. Granted that these dikes cutting granite are not syenite, the field relations point strongly to the younger age of the granite. Both in this region and elsewhere! the syenite is bordered by granite, the granite being much more gneissic than the syenite. Gradations between the two are common. It seems most reasonable to regard the granite as a border development of the syenite, derived from the same magma, and very slightly younger in age. Regarded from this point of view the Adirondacks form a well marked petrographic province, presenting rocks with very great variations in composition, grading from ultrabasic to acid, but all to be regarded as derived from one magma by differentiation. The great complexity of Adirondack structure results from the fact that these intrusives, together with the sediments of the Gren- ville series, into which they were intruded, have all been crushed so as to present similar planes of foliation, and at a later time have been extensively faulted. PART 5 Economic geology Graphite. Graphite and iron ores are the only products of economic importance. The graphite is mined at two localities, and occurs in many places on the quadrangle. ‘The demand for graphite in fine scales is limited, hence the industry has not developed to the full extent of the workable material. The mines at the town of Graphite have already been described by Professor Kemp; the graphite there occurs as drawn-out flakes among quartz grains in a layer bounded above and below by the garnet-sillimanite gneiss. There has been faulting, and the graphite has suffered from a shear along the bedding. At Rock pond, where a small mine has recently *H. P. Cushing. “Recent Geologic Work in Franklin and St. Lawrence Counties.” N. Y. State Geol. 20th An. Rept 1902. p. r23-r&2. 2N. Y. State Geol. 17th An. Rept 1899. p.539. 504 NEW YORK STATE ‘MUSEUM: : been opened, it also occurs along a line of movement in a gneiss which is probably of sedimentary origin but is not graphitic: In various other localities prospect holes have been opéned, and where-- ever successful there is evidence of shearing: The sandstones and limestones which are charged with small amounts. of graphite are not far from all of these openings, but the wall rock is apparently never a markedly graphitic one.. Less than half a mile east of the Rock pond locality the graphitic sandstone occurs on North pond; the drill-cores at Graphite went through graphitic limestone. It there- fore appears as though the graphite deposits were a result of impreg- — nation along a line of weakness by some products, possibly volatile hydrocarbons, originating from the distillation of ong fossilif- -erous sediments. | Thin sections of the shear zone at the western eau of the cliffs of Treadway mountain reveal flakes of graphite. The bounding rock is the quartzose gneiss of-probable sedimentary origin, and the graphite flakes appear secondary and are evidently related to an infiltration of iron-charged solutions. Pyrite invariably occurs asso- ciated with the graphite, and sometimes limonite and magnetite as © well. Any theory of the origin of graphite must explain its associ-. ation with these iron compounds. Dr Ernst Weinschenk has recently published a series of papers. entitled “ Zur Kenntniss der Graphitlagerstatten,” in which he takes up occurrences of graphite in various European localities. He finds that graphite may occur either as a result of contact metamorphism from a large intrusion of any kind into-a calcareous formation, or from injection in’ gaseous condition along planes of weakness ina disturbed area. He finds that graphite is never to be regarded as the final step in the process of ‘coal formation, and that at least in the Alps aud in (@eylom-ilve Ses is not due to eee or to dynamic metamorphism. Ea The Adirondack graphite is plainly of two kinds: that present as” an accessory. constituent of the limestone ‘and quartzite; and that occurring in a, secondary position along fault lines. The latter occurrence appears analogous to that described by Weinschenk as : Plate 17 WANG A graphite nodule in limestone. Ironville road Bois GEOLOGY OF THE PARADOX LAKE QUADRANGLE 505 | intrusive along planes of weakness, and can only be explained as an. injection of carbonaceous and ferruginous materials in a fluid or gaseous condition. A reducing action of iron compounds on: hydrocarbons might result in the formation of the graphite and pyrite which we constantly find associated. P But the widespread dissemination of graphite scales in sedimen- tary limestone and quartzite can best be explained on the organic : hypothesis. ‘There seems no possibility of any origin but that of a metamorphic product from some original constituent of the rock, and regional metamorphism is the only process by which it can_ reasonably be supposed to have been formed. It seems most prob- able that the original limestone and sandstone were heavily charged. with organic material which in the Prepotsdam period of meta- morphism was completely reduced and in some part volatilized. The organic material thus reduced remains in its original position. as graphite, while the volatilized portions spread along every avail- able plane of weakness and form the deposits of economic importance. | | | Titaniferous magnetite. Titaniferous iron ores appear on Moose — mountain. . The occurrence of these ore bodies is evidently to be explained in the same way as the aggregation of minerals in the anorthosites. The titaniferous ores always occur in the anorthosite, or gabbro, and represent the extreme development in the direction of producing an aggregation of iron minerals. The process. is entirely analogous to that of the production of anorthosite from gabbro by increase in feldspar, or of pyroxenite from gabbro by the @ecredse in augite. ‘There is no évidence of intrusion, nor of vein. formation in the occurrence of these ores, nor have they any relation to faults or crushed zones. The titaniferous iron ores of the Adirondacks have been fully treated by Professor Kemp.4 Nontitaniferous magnetites. Reference has already been made in Professor Kemp’s preliminary report? to the magnetite deposits of Hammondville and to the Schofield ore body. Both deposits occur in the granite of a type containing almost no ferro-magnesian *U. S. G. S. 19th An. Rept pt3. Economic Geology. p.379-422. 2Geology of Essex County. N.Y. State Geologist An. Rept for 1893 and 1895. SRL oe eR 506 NEW YORK STATE MUSEUM minerals. Both localities are very extensively faulted; the face of Skiff mountain shows a fault cliff, and. at -Hammondville- fault breccias are of frequent occurrence. Magnetite was found by the writer in the Desolate brook valley, southwest of Pharaoh mountain. It had been tapped by a mine, apparently long abandoned. The foot and hanging walls were of the same type of granite as those of the former localities. These deposits are in striking contrast to the titaniferous ore bodies, the magnetites showing no intimate relation to the wall rock. The conclusion seems inevitable that they are foreign to the granite, and produced in connection with one of the later intrusions, prob- ably secondarily enriched by percolating water.. Similar ores near Port Henry? have been described by Professor Kemp. There the ores are associated with an igneous intrusion of gabbro; they are always within an acid gneiss, but their proximity to the gabbro ren- ders their origin as contact occurrences the most reasonable view. The Hammondville and Schofield ore bodies are cut off by faults from all neighboring intrusions, but their most probable relationship seems to be with intrusive action. The alternative hypotheses would be either to regard thé mag- netite as a metamorphosed sedimentary bed and the Hammondville eneiss as a sediment, which is improbable in view of its similarity to the Pharaoh granite; or else to consider it a magmatic segregation from the granite, which seems improbable in so acidic a rock, notabiy poor in iron. 1J. F. Kemp. Geology of the Magnetites near Port Henry N. Y. and especially those of Mineville. Trans. Am. Inst. Min. Eng. 1897. EDUCATION DEPARTMENT JOHN M. CLARKE STATE GEOLOGIST ERSITY OF S STATE MUSEUM BULLETIN 96 PARADOX LAKE QUADRANGLE Geology by |. H. Ogiive: Henry Gannett, Chief Topographer- al e HMiWilson.Chief Geographer in charge. Paes } 3 Scale arbmy Triangulation by U.S.Coaet and Geodetic Survey. Fees Gi a a ee LS eee sa: z=! ¥ 4 Miles Topo, hy by Frank Sutton and E.B.Clark. a . 1 + 2 pesiay Sureyed in 1825. \ ones Soe oe eS ES * piilometers ¥ N i Contour Interval 20 fret. : Derturtn ixmenn Sea level fy a ‘ is. nf Ps , La oo ’ f. LEGEND GLACIAL GEOLOGY 200, 0°S Kames Stratified Dritt Terraces and Lake Bottoms Thin Till Potsdam Sandstone Conglomerate at base, yel- low or reddish sandstone in center, calcareous sand- atone at top. Quartzite Yellow or red, usually graphitic; above, shaly; below, succeeded by silli- manite gneiss. Hornblende gneiss Prevailing gray; contains interbedded schist, cut by numerous pegmatite veins; contains much sec- ondary quartz. Crystalline Limestone Usually graphitic {nterbedded schists. Lae | Gabbro Medium grained, black, dark-green Or brown; sometimes schistose; of- ten garnetiferous; dikes or bosses. Anorthosite Coarse grained, blulsa rock, chiefly labrador- ite, occasionally gneissic; white when granulated; contains tiraniferous ores Granite Usually banded, horn blende-granite-gnelss; o¢- casionally massive. Por- tions lacking in ferro- Magnesian minerals con- tain iron ores. Syenite | Medium grained, green or gray; weathers yellow or brown. When typically developed,augite syenite; GLACIAL FORMATIONS SEDIMENTARY FORMATIONS IGNEOUS ROCKS at times gabbroic; often uneissic. toe Trap Dikes Faults QUATERNARY CAMBRIAN PRECAMBRIAN a ee mea Vy! AD 9 Te OY AMER OTR RIT Sue Peres r dtu denials le Sac ar = rl Mer tre “gh « c f 4 fi . id i » i i : 4 > » i ‘ ne hha nape ey ta Mt Mate tn nt att i BI 9 ec ey ete ory a atiaa adsl ak. Seana ee Os ir goa ab enn Bema erat ore DN Dee xX _ The superior figures tell the exact ,iace on the page in ninths; e. g. 5003 _ means page 500, beginning in the third ninth of the page, i. e. about one third of the way down. Adams, Frank D., cited, 499°, 5003, 018. Adirondacks, topography and geol- ogy, 461'-63°; faulted region, 4627; trellised drainage, 462*; recent geologic work, 463?. Albite, 494%, 495°, 4974. Anorthosite, 483’, 485°-862, 4939, 495°, 500%, 5032; description, 498*-500°. Apatite, 495', 4968, 498', 498%. Augite, 497", 497°, 4981, 498%, 498°, 500°. Biotite, 494', 4943, 404", 494°, 495%, 495", 496°, 497", 498". Biotite schist, 493°, 495°. Brigham, cited, 462. Bronzite, 4978. Calciferous outlier, 467°. Calcite, 4947. Cambric drainage lines, 465°-679. Chilson lake, valleys, 4668. Chlorite, 494°, 4947, 4967, 498°. Cirques, 476}. Crown Point, 4709-725. Cushing, H. P., work on the geol- ogy of the Adirondacks, 4633; cited, 469%, 4849, 5039; mentioned, 483". Desolate brook, 4777. Diallage, sor?. Dikes, 4898-90”, 503}. Drainage modifications, 469'—78!. Economic geology, 5035-6’. Emmons, E., geologic work on the Adirondacks, 463%; cited, 4728, 4993. Epidote, 494°, 494", 4988. — Faults, 491°-92?. _ Feldspar, 4941, 4942, 494°, 4951, 4953, 497%, 498*, 500%. Foliation, 492°. Gabbro, 486%-872, 4959, 498", description, 500°-19. Garnets, 494%, 495*, 496", 4982, 498%, 498°, 499%, 499°, 5007, 501”, Sort. Glacial deposits, 4697—78!. Glaciology of the Paradox Lake quadrangle, 465°—78!. Gneiss, 4797; defined, 4799; horn- blende, 4797, 4939-955; quartzose, summary and conclusions, 502!—3°; sillimanite, 4792, 4817-831, 4958. Granite, 484, 493°, 495", 5032; descrip- tion, 4962-97°; summary and con- clusions, 502!—-35. Graphite, 495°, 5037-5°. Grenville series, sediments of, 479!. Grooves, 476}. 5031; Hague, 4759-77". Horicon, 477?. Hornblende, 4797, 4941, 404°, 4047, 496°, 496°, 497°, 4977, 498!, 498, 498°. Hornblende gneiss, 479°; description, 493°-95°. Hudson, north, 477°. Hypersthene, 4979, 498*, 500°, 500°. Igneous rocks, summary of evidence of relative age, 4877-928; petrog- raphy of, 4959-so1?. Ilmenite, 494!, 498°, 5008. Intrusives, 483°-844; relative ages, 503". Iron ores, 503’. Joints, 492’. Kames, 472°. Kaolin, 494", 494°. Kemp, J. F., acknowledgments to, 461°; work on the geology of the Adirondacks, 4633; cited, 465%, 481%, 4888, 491°, 5019, 5038, 5058, 5064. 508 NEW YORK STATE MUSEUM Labradorite, 494%, 495%, 498%, 4083, 498°, 498°, 4997, 4997, 500°, 500%, 501°. Lawson, A. C., cited, 5019. Limestone, 4797, 479°. Limonite, 504°. Lower base-level, age of, 460%. Magnetite, 4941, 494", 495', 496°, 406°, 4987, 4988, 504°; mnontitaniferous, 5058-6’; titaniferous, 499", 500°, 501°, 501", 505°. Mica schist, 4792, 4809-817. Microcline, 494%, 494°, 496", 497%. Microperthite, 495", 4968, 496°, 4974, 497", 497°, 498, 498°. Muscovite, 496°. 4948, 4953, Newland, D. H., work on the geol- ogy of the Adirondacks, 4636. — Norites, 500°. Oligoclase, 495%, 497. Orthoclase, 4948, 494°, 496°, 496°, 4974, 498°. Paleozoic formations, 490*-91°. Paradox Lake quadrangle, location and topography, 464!-65!; physiog- raphy and glaciology, 465°—78'. Pegmatites, 4875-897, 4939. Peneplains, 468'. Petrography, 4929-5036; of sedimen- tary rocks, 4938-959; of igneous rocks, 4959-5019. Pharaoh lake, 4772. Physiography of the Paradox Lake quadrangle, 465°-78!. Piedmontite, 494!, 4943, 494°. Plagioclase, 494?, 40948, 496%, 4969, 498°, 490%. : Porphyritic gneiss, 4968. Potsdam sandstone, 466%, 478°, 4903. Preglacial erosion history, summary of, 468°—60!. Putnam creek valley, 4668. Pyrite, 4958, 4959, 5045. Pyroxene, 4966, 497%, 501", Aog*, 501°, Quartz, 4941, 4045, 494°, 4048, 494°, 495', 495, 495°, 496°, 496°, 407}, 497*, 4977, 497°, 498!, 408%. Quartzite, graphitic, 4792; shaly, 4792, 483°. . Quartzose gneiss, summary and con- clusions, 502!—3°>. Rutile, 4959. Saussurite, 4947 Schroon valley, 466°, 4772. Sedimentary rocks, petrography of, 493°-959. Shaly quartzite, 483?. Shear zones, 492?. Sherman Corners, valley near, 4668. Sillimanite gneiss, 4797, 4817-831; ' description, 495°. Smyth, C. H. jr; work on the geology of the Adirondacks, 4634; men- tioned, 4837; cited, 4848. Spinel, 498%. Stratigraphic relations, summary of, 483°. | Syenite, 484%-85°, 493°, 405°, 5037; description, 497°-98'; summary and conclusions, 502!—3>, Ticonderoga, 472°-77!, Titaniferous iron ores, 500°. Titaniferous magnetite, 499’, 5013, 5017, 505°. Titanite, 4988; 500°. Topography of the Paradox lease quadrangle, 4641-65}. Towner pond, 472!. Trap, 493°. Trap dikes, 4808. Trenton limestone, 4909-915. Trout brook valley, 4667, 476°. Van Hise, cited, 4888. 500%, Weinschenk, Ernst, cited, 504°. Whortleberry pond, 4772. Williams, E. H., cited, 488%. Williams,.G. H., cited, 498", 501°. Wolf pond, 477?. Zeolites, 494°, 4967. Zircon, 4954, 405°, 496°, 498?, 498%. a New York State Education Department New York State Museum PUBLICATIONS Postage or express to places outside of New York State must be paid in addition to the price given. On 10 or more copies of any one publica- tion 20% discount will be given, the buyer to pay transportation. Editions printed are only large enough to meet special claims and probable sales. When the sale copies are exhausted, the price for the few reserve copies is advanced to that charged by secondhand booksellers, in order to limit their distribution to cases of special need. Such prices are inclosed in [ ]. All publications are in paper covers, unless binding is specified. Museum annual reports 1847-date. Oct, 1000. “dec. 4 Peck, C: H. N. Y. Edible Fungi, 1895-99. 106p. 25pl. Nov. 1900. 75c. This includes revised descriptions and illustrations of fungi reported in the goth, 51st and sed reports of the State Botanist. 9 Clarke, J: M. & Ruedemann, Rudolf. Guelph Formation and Fauna of New York State. 196p. 21pl. July 1903. $1.50, cloth. 6 Naples Fauna in Western New York. 268p. 26pl. map. $2, cloth. @ Ruedemann, Rudolf. Graptolites of New York. Pt 1 Graptolites of the [ower Beds. 350p. pl. Feb. too5: $7.50, cloth. Felt, E. P. Insects Affecting Park and Woodland Trees. In press. Clarke, J: M. Early Devonic of Eastern New York. In preparation. Natural history of New York. 3ov. il. pl. maps. Q. Albany 1842-094. MRsSiON IeZOOLOGY. De Kay, James EH. Zoology of New York: or, The New York Fauna; comprising detailed descriptions of all the animals hitherto observed within the State of New York with brief notices of those occasionally found near its borders, and accompanied by appropri- ate illustrations. 5v. il. pl. maps. sq. QO. Albany 1842-44. Out of print. 2 a introduction to the series by Gov. W: H. Seward. 178p. I ptr Mammalia. 13+146p. 33pl. 1842. eee copies with hand-colored plates. MUSEUM PUBLICATIONS v. 2 pt2 Birds. 12+380p. r4ipl. 1844. Colored plates. v. 3 pt3 Reptiles and Amphibia. 7+98p. pt4 Fishes. 15+415p. 1842. pt3-4 bound together. ; v. 4 Plates to accompany v. 3. Reptiles and Amphibia 23pl. Fishes 7opl. 1842. ° 3co copies with hand-colored plates. v. 5 ptS Mollusca. 4+27Ip. gopl. pt6 Crustacea. 7op. 13pl. 1843-44. Hand-colored plates: pts—6 bound together. | . . DIVISION 2 BOTANY. Torrey, John. Flora of the State of New York; coim- prising full descriptions of all the indigenous and naturalized plants hith- erto discovered in the State, with remarks on their economical and med- ical properties. 2v. il. pl. sq. ©. Albany 1843. ‘Out of print: v. I. Flora of the State of New York. i2t484p. 72pl. 1843. 300 Copies with hand-colored plates. v.2 Flora of the State of New York. 572p. 89pl. 1843. 320 copies with hand-colored plates. DIVISION 3 MINERALOGY. Beck, Lewis C. Mineralogy of New York; com- prising detailed descriptions of the minerals hitherto found in the State of New York, and notices of their uses in the arts and agriculture. ‘il. pl. Sq. ©... Albany 1842. Out of print. vV. I ptr Economical ee pt2 Descriptive Mineralogy. 24+536p. 1842. 8 plates additional to those printed as Bane of the text. DIVISION 4 GEOLOGY. Mather, W: W.; Emmons, Ebenezer; Vanuxem, Lard- ner: Elall james: Geology of New York. AN al: pi. sq. Q. Albany 1842-43. Out of print. v. I ptr Mather, W: W. First Geological District. 37+653p. 46pl.. 1843. v. 2 pt2 Emmons, Ebenezer. Second Geological District. 10+437p. 17pl. 1842. V-gupt3 Vanuxem, Lardner. Third Geological District. 306p. 1842. Wo pig Eval James. Fourth Geological District. 22+683p. t1gpl. map. 1843. DIVISION 5 AGRICULTURE. Emmons, Ebenezer. Agriculture of New York; comprising an account of the classification, composition and distribution of the soils and rocks and the natural waters of the different geological formations, together with a condensed view of the meteorology and agri- Ses productions of the State. 5v. il. pl. sq. Q. Albany 1846-54. Out of print. v. I Soils of the State, their Composition and Distribution. 11+371p. 2tpl. 1846. v. 2. Analysis of Soils, Plants, Cereals, etc. 8+343+46p. 42pl. 1840. With hand-colored plates. V.. 3°) Bruits. “ete. “Ste4ops 165i; v. 4. Plates to accompany y. 3. 205pl.. Tosi. Hand-colored. v. 5 Insects Injurious to Agriculture. &+272p. sopl. 1854. With hand-colored plates. d DIVISION 6 PALEONTOLOGY. Hall, James. Palaeontology of New York. 8v. il. pl. sq. QO. Albany 1847-94. Bound in cloth. v. I Organic Remains of the Lower Division of the New York System. 23+338p. ogopl. 1847. Out of print. v. 2 Organic Remains of Lower Middle Division of the New York System. &+362p. ro4gpl. 1852. Out of print... v. 3. Organic Remains of the Lower Helderberg Group and the Oriskany Sandstone. pti, text. latseee. 1859. [$3.50] pt2, 143pl. 1861. [$2.50] v. 4 Fossil Brachiopoda of the Upper Helderberg, Hamilton, Portage and Chemung Groups. 11+1+428p. gopl. 1867. $2.50. v. 5 ptr Lamellibranchiata 1. Monomyaria of the Upper Helderberg, Hamilton and Chemung Groups. 18+268p. aspl. 1884. $2.50. Lamellibranchiata 2. Dimyaria of the Upper Helderberg, Ham- ilton, Portage and Chemung Groups. 62+293p. 5Ipl. 1885. $2.50. TIN gh ag abled aeaeleitenanaaia tae ii a NEW YORK STATE EDUCATION DEPARTMENT — pt2 Gasteropoda, Pteropoda and Cephalopoda of the Upper Helderberg, Hamilton, Portage and Chemung Groups. 2v. 1879. v.1, text. 15+492p. w2,0E20pl. $2.50 for 2v, & Simpson, George B. v.6 Corals and Bryozoa of the Lower and Upper Helderberg and Hamilton Groups. 24+298p. O67pl. 1887. $2.50. — ®& Clarke, John M. v.7 Trilobites and other Crustacea of the Oriskany, Upper Helderberg, Hamilton, Portage, Chemung and Catskill Groups. 64+236p. 46pl. 1888. Cont. supplement to v.5, pt2. Pteropoda, Ceph- alopoda and Annelida. 42p. 18pl. 1888. $2.50. ——— & Clarke, John M. v.8, pti Introduction to the Study of the Genera of the Paleozoic Brachiopoda. 16+367p. 44pl. 1892. $2.50. =e Clarke, John M. v.8, pt2 Paleozoic Brachiopoda. 164394p. S4pl. 1894. $2.50. Catalogue of the Cabinet of Natural History of the State of New York and of the Historical and Antiquarian Collection annexed thereto. 242p. O. 1653. Handbooks 1893-date. 74%4x12%4 cm. In quantities, r cent for each 16 pages or less. Single copies postpaid as below. H5 New York State Museum. 52p. il. 4c. Outlines history and work of the museum with list of staff rgoz2. H13 Paleontology. iI2p. 2c. Brief outline of State Museum work in paleontology under heads: Definition; Relation to biology ; Relation to stratigraphy ; History of paleontology in New York. H15 Guide to Excursions in the Fossiliferous Rocks of New York. IAD. * SC. Itineraries of 32 trips covering nearly the entire series of Paleozoic rocks, prepared specially for the use of teachers and students desiring to acquaint themselves more intimately with the classic rocks of this State. H16 Entomology. 16p. 2¢. H17 Economic Geology. 44p. 4c. H18 Insecticides and Fungicides. 20p. 3c. H19 Classification of New York Series of Geologic Formations. 32p. 3c. Maps. Merrill, F: J. H. Economic and Geologic Map of the State of New York; issued as part of Museum bulletin 15 and the 48th Museum Report, Vet soxo7 cm. 1694. Scale 14 miles to 1 inch 5c. Geologic Map of New York. igor. Scale 5 miles to 1 inch. Jn atlas form $3; mounted on rollers $5. Lower Hudson sheet 60c. The lower Hudson sheet, geologically colored, comprises Rockland, Orange, Dutchess, Put- nam, Westchester, New York, Richmond, Kings, Queens and Nassau counties, and parts of Sulli- van, Ulster and Suffolk counties ; also northeastern New Jersey and part of western Connecticut. Map of New York showing the Surface Configuration and Water Sheds. 1001. Scale 12 miles to 1 inch. 5c. Geologic maps on the United States Geological Survey topographic base; scale I in. =I m. Those marked with an asterisk have also been pub- lished separately. *Albany county. Mus. rep’t 49, v. 2. 1898. 50. Area aijund Lake Placid. Mus. bul. 21. » 1808. Vicinity of Frankfort Hill [parts of Herkimer and Oneida counties]. Miaisssnep + 51,.v. 1. 1890. Rockland county. State geol. rep’t 18. 1899. Amsterdam quadrangle. Mus. bul. 34. 1900. *Parts of Albany and Rensselaer counties. Mus. bul. 42. 1901. oc. eNaaeara River. Mus. bul-’45.. 1901. 25. Part of Clinton county. State geol. rep’t 19. 1901. Oyster Bay and Hempstead quadrangles on Long Island. Mus. bul. 48. IQOI. Portions of Clinton and Essex counties. Mus. bul. 52. 1902. Part of town of Northumberland, Saratoga co. State geol. rep’t 21. 1903. Union Springs, Cayuga county and vicinity. Mus. bul. 69. 1903. *Olean quadrangle. Mus. bul. 69. 1903. Joc. *Becrait Mt with 2 sheets of sections. (Scale 1 in. —'%4 m.) Mus. bul. OOF 1003. 20c. *Canandaigua-Naples quadrangles. Mus. bul. 63. 1904. 20c. *Little Falls quadrangle. Mus. bul. 77. 1905. 1r5c. *Watkins-Elmira quadrangle. Mus. bul. 81. 1905. 200. Siulisy quadransle. Mus: bul.-82. 1605. Toe *Salamanca quadrangle. Mus. bul. 80. 1905. roc. 1095) 130 A 3 ® cs) ° oat an ‘U Se ‘et .t) mM Se. ® rt a] 2 e 9 a f& yey ® i ; SS cod ‘Bem ony New York State Education Department ‘ New York State Museum The New York State Museum as at present organized is the outgrowth of the Natural History Survey of the State commenced in 1836. This was established at the expressed wish of the people to have some definite and positive knowledge of the mineral resources and of the vegetable and animal forms of the State. This wish was stated in memorials presented to the Legislature in 1834 by the Albany Institute and in 183s by the American Institute of New York city and as a result of these and other influences the Legislature of 183s passed a resolution requesting the Sec- retary of State to report to that body a plan for “a complete geological survey of the State, which shall furnish a scientific and perfect account of its rocks, soils and materials and of their localities; a list of its minera- logical, botanical and zoological productions and provide for procuring ~ and preserving specimens of the same; etc.” | Pursuant to this request, Hon. John A. Dix, then Secretary ak State, presented to the Legislature of 1836 a report proposing a plan for a com- plete geologic, botanic and zoologic survey of the State. This report was adopted by the Legislatute then in session and the Governor was authorized to employ competent persons to carry out the plan which was: at once put into effect. 3 The.scientific staff of the Natural History Survey of 1836 consisted of John Torrey, botanist ; James E. DeKay, zoologist; Lewis C. Beck, mineralogist; W. W. Mather, Ebenezer Emmons, Lardner Vanuxem and Timothy A. Conrad, geologists. In 1837 Professor Conrad was made paleontologist and James Hall, who had been an assistant to Professor Emmons, was appointed geologist to succeed Professor Vanuxem, who took Professor Conrad’s place. ‘The heads of the several departments reported annually to the Gover- nor the results of their investigations, and these constituted the annual — octavo reports which were published from 1837 to 1841. The final reports were published in quarto form, beginning at the close of the field work in 1841, and 3000 sets have been distributed, comprising four vol- umes of geology, one of mineralogy, two of botany, five of zoology, five of agriculture, and eight of paleontology. Rk ere. ai | on 4 wee ay GE OO Ne ee oS od = =! za hens ns I\LILSNI_NVINOSHLINS_ S3IYVYSIT LIBRARIES SMITHSONIAN _INSTITU ee: S eS = " S. o = Ss) = Yt, 2 aoa 2 we 5 2 GZ 2 Y q > ty 4 & WY = ) = Ui y. bE) =a WY @ rz aoe ae Oo ie Ss = w Zz w ARIES SMITHSONIAN INSTITUTION NOILMLILSNINVINOSHLINS Sa14uV 4% ” z 7) = 7) " =} Zz Y + = ar yy Oo Sy SAYS: . ‘ > = ik YS > s = i za “ee : ta Y .. z Ww > ty NVINOSHLINS S3IYVYGIT_ LIBRARIES SMITHSONIAN INSTITU Gi = i ) Zz = ~ N Ww iJ Tp) O} = a < eS = pe oc = 2 S = rs} f i = =f = Y wd ARIES_ SMITHSONIAN INSTITUTION NOILNLILSNI_NVINOSHLINS S31 YY! iv i) iy ‘ hy >! r" ILS : ‘i “yy ALILSNI NVINOSHLINS S3IYVYdIT LIBRARIES ANS QYe .. * ARIES SMITHSONIAN INSTITUTION NOILOALILSNI NVINOSHLINS S314 SIIMVUGIT LIBRARI INSTITUTION INSTITUTION INSTITUTION SMITHSONIAN _ INSTITL y NVINOSHLINS S31uVvagd SMITHSONIAN NVINOSHLIWS \ SMITHSONIAN SMITHSONIAN a 7 rt) A, NOILNLILSNI LIBRARIES $4 bbe LIBRARIES LS 2 VLILSNI NVINOSHLINS S3!IYVYdIT LIBRARIES SMITHSONIAN_INSTI ( \: a : INSTITUTION NOILNLILSNI Ww uJ . te fl J. P 2 eZ 2 U7 fp B m = ri x m ; wn = w . on : INSTITUTION NOILNLILSNI NVINOSHLINS S3I1YY wn” ie 7) z w ; = < = = = i = = / 2 é ey f, 5 2 yy, 2 = 2 a =) = = i >" = > Tp) o Pe Zz Ww za ud _NVINOSHLINS S3IYVYGIT LIBRARIES SMITHSONIAN _INSTIT > 7) = 7) = | STU YS) SSN rp ud = K5e e\ a - Ky ie: w , 3 (RN wie .< (2 ye) a < te ‘est d a esN os ea ll fing oR ale TSS ro) a if er Z al oa eae ae LNLIZSN!_ NVINOSHLINS S3!YVYdIT LIBRARIES SMITHSONIAN INSTIT ae of = a a a a TO DOWN = ow = Yip O “a aN WS Sf > — Yj, % > VUSG oa RNS - aa a 2 VASA Sys sia wn * ie), = D z o RARI ES SMITHSONIAN INSTITUTION NOILNLILSNI _NVINOSHLINS S23 iYy = < = ft, 3 GR = Oh z é z , 8 2 Y = a 2 ay 7 = = AS > = > a ” oe = Ww za NVINOSHLINS S3ZtYVYEIT LIBRARIES SMITHSONIAN {NSTIT NOILALILSNI LIBRARIES NOILNLILSNI LIBRARIES NOLLMLILSNI INSTITUTION NOILALILSNI NVINOSHLINS S31u% C = r z ‘ow = = o. 2 5 = a =m Es e F = = = FE O Z ae Be a oon 1yYVvyad ae yo MITHSONIAN INSTIT tt ful = = = =! z= \\\ Lf 3 5 a : a tp * g! : Z a & Ss > = ae = , Ww) Ps ww) . = Wy) RARI ES (SMITHSONIAN INSTITUTION NOILNLILSNI S31u\ = 7) us Le - a us ow. = a toe. oc <% oa wad NLILSNI_NVINOSHLINS S3IYVYUGIT LIBRARIES SMITHSONIAN INSTIT eee 5 ai S os ce ao oo w a hy wo , . E 5 $% > > WS a > ras typ fp fi. > - x N\ ws a = hy fad: a ° \ \S a in n wo as BAe om on a — Oo = n gARI ES SMITHSONIAN INSTITUTION | NOILNLILSNI _ NVINOSHLIWS Sa luy = = = = = GY, = 5 wy 2 » 5 2 gy e o Y) i N . . w i WwW ip) Upp = = XS s 2. iy ay 7? 2 a 5 Bit) e NVINOSHLIWS Sauvugiy LIBRARIES SMITHSONIAN INSTITL ARIES RARIES WLM 3 9088 01300 7430