Qass Q E lE -^ Book .B 6 F^ Professional Paper No. 53 _ ,„ „ , , „, (0, Underground Waters, 57 DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY CHARLES D. WALCOTT, DIRECTOR GEOLOGY AND WATER RESOURCES BIGHORN BASIN, WYOMING OASSIUS A. FISHEK WASHINGTON GOVERNMENT PRINTING OFFICE 1906 Professional Paper No. 53 j B, Descriptive Geology, 91 (0, Underground "Waters, 57 DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY CHARLES D. WALCOTT, Director GEOLOGY AND WATER RESOURCES BIGHORN BASIN, WYOMING OASSIUS A. FISHER WASHINGTON GOVEENMENT PRINTING OFFICE 1906 «Kii \^> Many of the names given in this table have been proposed by N. H. Darton for the Bighorn Mountain region. They are defined in a Comparison of the stratigraphy of the Black Hills, Bighorn Mountains, and Rocky Mountain Front Range: Bull. Geol. Soc. America, vol. 15, 1904, pp. 379-448, pis. 23-34. U.S.GEOLOGICAL SURV 3 GEOLOGICAL SURVEV PROFESSIONAL PAPER NO 53 PL- CROSS SECTIONS OF THE BIGHOKN BASIN, ■Wl'OMING.BYC-A.nSHER STRATIGRAPHY. VJ PBE-CAMBRIAN ROCKS. GRANITE. General statement. — The underlying formation of the Bighorn uplift is a massive granite which has been raised several thousand feet above its original position. In the northern part of the Bighorn Mountains the overlying sedimentary rocks con- ceal the greater part of the granite, but it appears in irregular areas in several por- tions of the district. The most extensive exposures are about Bald Mountain, in the anticline extending from Red Gulch to a point west of Medicine Mountain, in the valley of Porcupine Creek, in Cookstove basin, and in the deeper portions of the canyons of Shell Creek. The rock is generally very massive and is of pre-Cambrian age. Granite is also exposed in Shoshone Canyon and on the north slope of the Owl Creek Mountains. Granites of the Bighorn Mountain region. — The granites of the northwestern portion of the Bighorn Mountains are mainly a coarse-grained red variety, but there are a few small areas of a fine-grained gray granite. The so-called red granite has a light-grayish appearance at a distance, but when viewed at close range is seen to be characterized by a more or less pronounced reddish tinge, due to the abundance of pink feldspar in it. The rock often presents a well-defined system of joints, and weathers into bold, rounded forms. Its surface is usually rough, owing to differential weathering, and the large feldspar phenocrysts often have sufficient prominence to give it a porphyritic appearance. The principal constituents are feldspar, quartz, and mica, occurring in varying proportions. The gray granites of the district are generally uniform in color and texture and in the kind, amount, and distribution of their component minerals. There are, however, local areas where the ferromagnesian minerals predominate, giving the rock a very dark appearance. The gray granite presents in some localities a well- defined system of joints, the rock weathering into angular blocks or slabs, making the topography very rugged. To the unaided eye this rock is of dark-gray color, of medium to fine texture, and is marked occasionally by lines of secondary movement. The principal constituents are feldspar, quartz, and biotite. Dilces of the Bighorn Mountain region. — Several dikes of diabase and peridotite cut the granite area described above. They vary in width from 2 to 25 feet and usually extend transversely or at a wide angle to the major axis of the main uplift. These dikes, owing to the greater hardness of the rock, offer greater resistance to atmospheric agencies than the softer granites into which they have been intruded, and consequently stand out in more or less prominent ridges that extend across the . granitic areas. The rock weathers into cubes 2 to 6 inches square, the ultimate product of decomposition being a reddish-brown residual soil which in color presents a striking contrast to that derived from the lighter colored country rock. There are several of these dikes in the vicinity of Bald Mountain and on Porcupine and South Beaver creeks. In the granite flats west of Bald Mountain there is a branch dike extending north-northwest. It passes east of Medicine Mountain under the Dead- wood sandstone for about a mile and appears to be continued due northward by one of the dikes crossing Porcupine Creek, its entire length being at least 5 miles. Small 10 GEOLOGY AND WATEE KESOUECES OF BIGHOEN BASIN. dikes, or chimneys, of diabase appear in the vicinity of Fortunatus Mill, especially to the southwest. They are from 10 to 20 feet in diameter and of circular or elliptical outline. These smaller masses are of variable character and some of them exhibit considerable mineralization. The distribution of the dikes is not shown on the geologic map. A microscopic examination of the diabase shows that the constituent minerals are feldspar, augite, and quartz, with biotite, magnetite, chlorite, and apatite occurring in smaller amounts. Granite and diabase of Rattlesnake Mountain. — A small area of granite is exposed in Shoshone Canyon between Rattlesnake and Cedar mountains. The rock is moderately coarse grained and massive and appears to have been subjected to con- siderable pressure, for in places it is schistose. It has a well-defined system of joints, and weathers into bold, rounded forms. The granite is cut by dikes and sills of a quartz-bearing diabase. No microscopic examination of the granite of this locality has been made. One of the diabase dikes is shown in PI. VI, B, p. 12. Granite of Owl CreeJc Mountains. — The granites of the north slope of the Owl Creek Mountains, a small area of which is exposed within the district, appear to have no essential variation from those above described. CAMBRIAN SYSTEM. DEADWOOD FORMATION. General relations. — The oldest sedimentary formation outcropping within the area is a series of beds of sandstone, shale, limestone, and conglomerate of middle Cambrian age that have a thickness ranging from 700 to 1 ,500 feet. To these beds, in the Bighorn Mountain province, Mr. Darton has applied the name Deadwood formation. The basal member is a sandstone, somewhat conglomeratic, lying on the granite. Its thickness varies from 10 to 30 feet. Next above this is a series of greenish-gray shales with layers of sandstone and sandy shale, having in all a thick- ness of about 300 feet. This member is succeeded by a sandstone 25 to 40 feet thick, which in turn is overlain by several hundred feet of shale containing thin-bedded conglomeratic sandstones and limestones. Overlying these beds are alternating layers of limestone and limestone conglomerate made up of fiat limestone pebbles. The pebbles are mostly green in color, but on freshly broken surfaces are gray to pale pink. These limestones and conglomerates have a thickness of about 200 feet and are sometimes capped by a layer of white sandstone, which is regarded as the base of the Bighorn formation. Fossils have been observed at various horizons, chiefly in the limestones a short distance above the middle of the formation, in the sandstones next below, and in the basal sandstones. The prominent forms are Dicellomus politus and Ptychoparia owenia, the latter occurring mainly in the basal sandstone. AhsaroJca Mountain region. — In Shoshone Canyon on the western side of the district the entire succession of beds comprising the Deadwood formation is exposed. The limits of the formation here are well defined, but the thickness is somewhat diminished. At the top there is a thin-bedded limestone alternating with layers of green shale and flat-pebble conglomerate; below this occur sandstone and shale in S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 63 PL. Formation General Character East side West side Dark shale with 1100-1200' Cherty limestone. White fine limestone. Red shale and sandston 1 r 230' 150' Soft white limestone, thin bedded. Hard, massive, buff limestone with silica 5treal;%..*r> * ■ •.,,•/*■•-•, ■■HBK'"^>.ilA'*.*' ' . '->..-.• ' ... - - B' '■ ■' •^-^■#-'^--* ^^K "'"^V :.^'*C-^^' BH^^ ^ __^_^ ^-l '.tJ^RiLii/- _ ." ^ ;^ _ '^'-j^ i'. TYPICAL AMSDEN FORMATIO^ V\^estern slope of Bighorn Mountains. STRATIGRAPHY CARBONIFEROUS ROCKS. 15 AMSDEN FORMATION. General relations. — Overlying the Madison limestone and generally extending far up the outer slopes of the mountains, are limestones, shales, and cherts, constitut- ing the Amsden formation. This has an average thickness of 150 feet; its lower portion consists of bright-red shale, 60 to 80 feet thick, often containing layers of limestone, and its upper portion of a thin-bedded sandy limestone, in part containing extensive deposits of chert. Fossils are not abundant, but some that have been collected by Mr. Darton from upper beds on the eastern side of the district are of Peimsylvanian age. AhsaroTca Mountain region. — The Amsden outcrop extends nearly halfway across the district along the front range of the Absaroka Mountains. It occupies a wide area on the higher slopes of the Rattlesnake and Cedar Mountain Range. In the vicinity of Black Mountain the dips are steep and the formation does not extend far up the slopes, but farther north and west, in the low, sloping plateau, it is exten- sively exposed. On the south side of Clark Fork Canyon, where the beds dip steeply, the formation is composed of a basal member of red sandy shale 75 feet thick, overlain by a series of alternating beds of gray sandstone, chert, and fine-grained slabby limestone. In Shoshone Canyon (PI. VII, A) the formation contains the usual red sandy layer at the base, followed in ascending order by harder beds of sandstone, quartzite, lime- stone, and chert. The following section was measured on the northern side of Shoshone Canyon : Section of Amsden formation on north side of Shoshone Canyon, Wyoming. Feet. Tensleep sandstone Gray compact limestone 20 Dark-red sandstone, very hard 3 Light-gray limestone, very compact, containing layers of chert 20 Alternating layers of light-colored limestone and deep-red sandy shale 20 Red sandy shale containing few sandstone layers 60 Madison limestone. 123 Bighorn Mountain region. — On the eastern side of the basin the Amsden forma- tion is about 200 feet thick. Where the dips are steep the outcrop zone is narrow, but, in other places, as on the sloping plateaus on both sides of Horse Creek, it is broader and extends nearly to the main divide. From Cottonwood Creek northward it underlies a number of plateaus, forming wide benches on the mountain slopes, but here it is largely covered by later formations. It is deeply dissected by Devil Canyon and the valleys of Deer and Trout creeks. The lower member of the Amsden forma- tion consists of the usual bright-red sandy shale overlying the Madison limestone, which last is often deeply stained by the red shales. In the basal shale of the Amsden there is a fine-grained, light-colored limestone about 10 feet thick, and above the shale are sandy limestones, containing in places extensive deposits of chert, which weather out and accumulate on the surface (PI. VII, B). The thickness of the 16 GEOLOGY AND WATEB RESOURCES OP BIGHORN BASIN. formation averages 200 feet, but is much less than this in some locahties. At Shell Creek Canyon the following section was measured : Section of Am sden formation on Shell CreeTc east of Shell, Wyo. Feet. Pinli sandstone overlain b)' flesh-colored massive sandstone of Tensleep formation 4 Light-red to maroon sandy shales. 40 Gray sandy limestones, thin-bedded at top and containing much chert 20 Ked shale. '. 75 Hard, fine-grained, flesh-colored limestone 10 Red shale lying on blue-gray Madison limestone , 25 174 Near the base of the formation in this locality there are some very peculiar concretions, composed of masses of silica, suggesting a coral in appearance. They vary in diameter from 6 inches to 2 feet. Owl Creek Mountain region. — The Amsden formation is exposed on the northern slopes of the Owl Creek Mountains in the southwestern part of the district, where it exhibits the usual stratigraphic sequence. The thickness here is about 200 feet and the shales at the base have the characteristic bright-red color. TENSLEEP SANDSTONE. General relations. — The Tensleep sandstone, which overlies the Amsden forma- tion, is prominent among the formations flanking the front range of the Bighorn, Absaroka, and Owl Creek mountains. It is also exposed in the Sheep Mountain uplift, on the eastern side of the basin, and in the high anticline southeast of Hyatt- ville. Its thickness varies from 30 to 230 feet. The formation is composed of massive, cross-bedded sandstone alternating with beds of limestone. AbsaroJca Mountain region. — The formation is extensively exposed on the slopes of Rattlesnake and Cedar mountains. It outcrops along the base of Black Mountain and extends far up the slopes of the inclined plateau to the north. From the vicinity of Clark Fork Canyon to the Montana line it appears in a narrow zone. In the region of Rattlesnake Mountain the sandstone is a massive, cross-bedded, light- colored rock, 150 feet thick, the upper portion of which is sometimes quartzitic. On the northern side of Shoshone Canyon, a short distance above its mouth, a section of the Tensleep sandstone, including the overlying limestones, was measured. BigTiorn Mountain region. — Along the base of the Bighorn Mountains, on the east side of the basin, the Tensleep sandstone usually gives rise to a ridge of moderate prominence on the lower slopes. The formation is only about 30 feet thick in the northern part oi the area, but its thickness increases rapidly southward, and in Horse Creek Canypn is 150 feet. Generally the thickness varies from 100 to 125 feet. Small outliers of the formation lie high on the divide on both sides of Bear Creek; also along the road east of Cloverly, on the divide north of the mouth of Shell Creek Canyon and on the divide south of White Creek. The predominant rock is white to buff sandstone, in thick massive beds, which are cross-bedded and often weathered into very irregular forms (PI. VIII, A, B). Where the formation U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 53 PL. TENSLEEP SANDSTONE. A. Western slope of Bighorn Mountains. B. No Wood Canyon, Bighorn basin, Wyoming. STRATIGEAPHY — CARBONIFEEOUS ROCKS. 17 is thick, the basal member usually consists of 50 feet or more of soft buff sandstone not clearly separable from the underlying Amsden formation, which usually occurs in thinner beds. The upper sandstone frequently contains a few thin limestone layers, which in other districts in the Bighorn Mountains have yielded Pennsylvanian fossils. Owl Creek Mountain region. — To the southward the Tensleep sandstone is exposed only in a few small areas within the district considered in this paper. The beds in these localities exhibit no unusual features. EMBAR FORMATION. General relations. — Overlying the Tensleep formation, on the slopes of the Owl Creek Mountains, are massive limestone and cherts, to which Mr. N. H. Darton has applied the name Embar formation, from Embar post-office, at which the beds are typically developed. The formation has a thickness of between 200 and 250 feet, and usually gives rise to long dip slopes. It is widely exposed all along the northern side of the Owl Creek Mountains, and in the vicinity of Thermopolis extends far up l^e slopes. Where the formation is typical, the basal member usually consists of 50 feet or more of alternating layers of light-buff limestone and sandstone. Above this there is a dark-gray fossiliferous sandstone 4 to 6 feet thick, overlain by about 90 feet of cherty limestone. Next above there is 30 to 50 feet of limestone, massive in character, capped by about 50 feet of compact sandstone, merging in color from a gray at the top to a brownish-gray or yellowish near the base. In the vicinity of Anchor the top member of the formation is 20 feet thick, resting on the massive limestone. The formation is extensively exposed throughout the Owl Creek uplift, but only a few small areas occur within the southern part of the district to which this report relates. They are found generallj^ on anticlinal ridges branching from the main uplift. One of these occurs east of Anchor, where it is crossed by South Fork of Owl Creek, in a deep gorge, and another is southeast of Embar. The formation also appears in the more elevated portion of the anticline which passes through Thermopolis. Large numbers of fossils occur in the Embar limestone in the walls of Bighorn Canyon south of Thermopolis. A collection was made at this locality by Mr. N. H. Darton, from which one mollusk has been identified by Dr. G. H. Girty as Spiriferina pulchra. This form is believed to characterize a horizon just below the so-called Permo-Carboniferous of the Wasatch Mountain region. Rattlesnake and Cedar mountains. — On the flanks of Rattlesnake and Cedar mountains, immediately overlying the Tensleep sandstone, there is exposed a succession of limestone, chert, and sandstone about 80 feet thick, which is believed to be the equivalent of the Embar formation. A section of these beds on the northern side of Shoshone Canyon is as follows : Section of Embar formation in Shoshone Canyon, Wyoming. Chugwater formation. Feet. Gray compact fossiliferoas limestone 15 Alternating layers of cherty limestone and sandstone 65 18 GEOLOGY AND WATER RESOUECES OF BIGHORN BASIN. The top limestone of this formation contains fossils which are believed to be of Pennsylvanian age. The fossils collected from the limestone at the head of a small tributary of Sulphur Creek, on the eastern side of Cedar Mountain, have been identified by Doctor Girty as follows : Fossils from east side of Cedar M^hintain, Wyoming. Fenestella ( ?) sp. Fragments of pelecypods. . Orthothetes n. sp. Laevidentalium canna. From the same horizon, on the western end of a prominent red hill on the southern side of Trail Creek, the following fossils were collected : • Fossils from Trail Creek, Wyoming. Enchostoma n. sp. Nucula (?) sp. Myalina ( 'i) sp. Fragments of pelecypods. Myalina cf . M.. perattenuata. Laevidentalium canna. Leda sp. TRIASSIC SYSTEM. (?) CHUGWATEK FORMATION. General relations. — The Chugwater formation, which comprises the red beds of the northern Front Range of the Rocky Mountains, is extensively exposed through- out the Bighorn basin. The formation varies in thickness from 600 to 800 feet, and consists mainly of soft, massive, red sandstones with layers of gypsum and limestone. In different parts of the basin it shows considerable variation in character. Along the eastern side of the area there are generally two limestone beds, near the base, which are underlain by about 100 feet of red sandy shale, containing deposits of gypsum. The upper limestone is overlain by several hundred feet of soft red sand- stone, usually outcropping in a line of prominent cliffs (PI. IX, A, B). Above these sandstones there are about 100 feet of red sandy shale, which contains a layer of hard, thin-bedded, light-colored limestone at or near its base. Higher up are some beds of gypsum and at the top several layers of thin-bedded white limestone. Along the Absaroka front range, in the western part of the area, the formation presents a somewhat different stratigraphic succession. The basal member, about 30 feet thick, consists mainly of beds of light-gray, thin-bedded sandstone alternating with layers of limestone, the whole resting with apparent conformity on the massive limestones that comprise the upper part of the Tensleep formation. This member is overlain by 500 to 600 feet of soft, massive, red sandstones, capped by 20 to 30 feet of white gypsum. Above the gypsum there is a 12-foot layer of red sandy shale containing thin seams of gypsum which comprise the uppermost member of the formation. Distribution. — The Chugwater formation occurs in extensive outcrops, especially along the eastern side of the basin. From the southern margin of the district to beyond Shell the outcrop has an average width of about 4 miles. Between Horse Creek Canyon and Cottonwood Creek, where there are steep dips, it occurs in a narrow zone along the base of the mountains. From Cottonwood Creek to the PROFESSIONAL PAPER NO. 53 PL. STRATIGRAPHY TRIASSIC ROCKS. 19 Montana line the dips decrease and the outcrop spreads out over a wide area, in which the formation caps several small plateaus and extends eastward far up the slopes of the mountains. The Sheep Mountain uplift exposes about 80 square miles of red beds on either side of Bighorn River from near the mouth of Shell Creek to the vicinity of Lovell. Along the western side of the basin the zone of outcrop is gen- erally narrow, but it is present on both sides of Rattlesnake and Cedar mountains and along the base of the Absaroka and Beartooth ranges. In the southern part of the district the Chugwater red beds occupy an extensive area in the central part of the Thermopolis anticline and an area of equal size between Embar and Anchor. Local stratigraphy. — Though the Chugwater formation is generally well exposed, it is often difficult to obtain a complete section at one locality. The following measurements of the lower part of the formation were obtained on Shell Creek east of Shell, Wyo.: Section of lower part of Chugwater formation east of Shell, Wyo. Feet. Limestone, weathering porous, lying beneath about 600 feet of red shale and sandstone 4 Red shale - : 25 Thin-bedded purplish limestone 6 Red shale - - . - - _ - 25 Gypsum 12 Purplish sandy shale 4 Red shale resting on 75 feet of Tensleep sandstone 20 In Red Gulch, east of Cloverly, the lower members of the Chugwater formation are as follows : Section of lower part of Chugwater formation in Red Gulch, Wyoming. Feet. Limestone, weathering porous, overlain by about 500 feet of red shales and sandstone 20 Green shale 15 Limestone, weathering porous 6 Green shale 10 Limestone, weathering porous 4 Red shale - 35 Thin-bedded purplish limestone 10 Red shale with gypsum on Tensleep sandstone 125 225 At the mouth of Crooked Creek the lower beds of the Chugwater formation are as follows : Section of lower part of Chugwater formation on CrooJced Creek, Wyoming. Feet. Alternating layers of white compact limestone and gray limestone, weathering porous 30 Red and green clays 2 Alternating layers of light-gray limestone and green clay 8 Red sandy shale, green near top 35 Gray limestone \ Gray sandstone 1 Dark-red sandy shale on Tensleep sandstone 6 82§ 20 GEOLOGY AND WATER BBSOUECES OP BIGHORN BASIN. Near Alkali Creek, northwest of Cloverly, Wyo., a complete section of the Chug- water formation was measured : Section of Chugwater formation northwest of Cloverly, Wyo. Feet. Dark-red shales overlain by gray shales containing Jurassic fossils 60 White limestone with red shale partings 10 Red shale 20 Thin-bedded, fine-grained light-colored limestone 10 Red shale 60 Red sandy shale 50 Red sandstones, some red shale 224-!- Green shale 20 Massive limestone, weathering porous 50 Red shale, not well exposed 40 ° Thin-bedded pui-plish limestone. 6 Red shale, not well exposed, resting on On the south side of Clark Fork Canyon, in the northwestern portion of the area, the formation has a thickness of about 750 feet. Here the limestone members appear to be absent, with the exception of a few thin layers at the base. The order of the beds is as follows : Section of Chugwater formation on the south side ofClarlc ForJc Canyon, Wyoming. Feet. White massive gypsum overlain by Sundance beds 25 Soft, red, massive sandstone containing layers of gypsum 725 Greenish sandy shale containing thin limestone layers on Tensleep sandstone lO-f- 760 About 6 miles northwest of Thermopolis, on the north side of Owl Creek, the following section of Chugwater formation was taken : Section of Chugwater formation near Watson's ranch on Emhar road jv^t north of Owl Creek, Wyoming. Feet. Red beds with an occasional greenish sandy layer 210 Gray massive sandstone 40 Red beds 20 Gray massive sandstone 10 Red shale with few sandstone layers 120 Gray, thin-bedded, porous limestone intercalated with red shale 35 Alternating layers of drab fissile limestone and red thin-bedded shale 35 Deep maroon shale with spongy, angular, calcite concretions 9 479 STRATIGRAPHY TRIASSIC AND JURASSIC ROCKS. 21 Age of the formation. — The age of the Chugwater formation is not definitely known. Along the western side of the basin no fossils have been observed in the beds, and those that have been collected farther east, from the limestones in the lower part, do not furnish satisfactory evidence. The forms are not sufficiently complete or distinctive to be classed as Permian or Triassic. On Beaver Creek, northeast of Cleverly, the basal limestones contain pelecypod shells in great abun- dance, but they are generally too much deformed by compression to be determined. They resemble the genus Schizodus of the Carboniferous, one specimen being similar to S. wTieeleri and another similar to S. symmetricus. The shells were diminutive, and it is possible that they are some other genus of Mesozoic age. A few fossils were obtained near Kane, but they are so small and so poorly preserved that it is not possible to determine their generic characters or relations. One shell, accord- ing to Doctor Girty, closely resembles Myalina swallowi of the Upper Carboniferous, but this fossil may possibly be a Pteria or Bakewellia or a Mesozoic Mytilus or Modiola. Another species suggested, by its form, Astartella, possibly A. gurleyi. All these suggestions are based on features which might also be interpreted as those of Mesozoic forms, but Doctor Girty and Mr. Schuchert are inclined to believe that they are Permian. As to the age of the overlying red sandstones of the Chugwater formation, there is no definite information; they may belong to the Permian or they may represent deposits of Triassic times. JURASSIC SYSTEM. SUNDANCE FORMATION. General relations. — The marine Jurassic deposits of the Bighorn Mountains, to which the Black Hills name, Sundance, has been applied by Mr. Darton, reach a considerable thickness and carry an abundant fauna in the Bighorn basin area. The formation retains a moderately uniform thickness throughout the district, but shows variation in stratigraphy. It consists of sandstone, limestone, and shales. The shales usually predominate and have a greenish-gray color. The formation generally outcrops in a narrow zone flanking the base of tha uplifts on the eastern, western, and southern sides, but along Shell and Trapper creeks, on the eastern side of Bighorn River from Bear Creek to beyond Alkali Creek, on each side of Crooked Creek, and at the southern end of Rattlesnake Mountain, owing to low dips, the outcrop widens greatly. In the southeastern part of the district, from Hyattville to Redbanks, the zone of outcrop averages a mile in width. AhsaroTca Mountain region. — Along the base of the Absaroka and Beartooth mountains the Sundance formation has a thickness of about 350 feet. Its base comprises a succession of light-gray to white thin-bedded limestone alternating with red and green sandy shale, having a total thickness of about 65 feet. Next above are 50 to 70 feet of dark-red sandy shale, overlain by about 150 feet of greenish fossiliferous shale containing layers of massive gray sandstone. Above this member, at the top of the formation, is a greenish, sandy shale with at least two and some- times more layers of dark greenish-gray, fossiliferous sandstone. The following 22 GEOLOGY AND WATER RESOURCES OF BIGHORN BASIN. section of the Sundance formation was measured on Trail Creek, 8 miles northwest of Cody, Wyo.: Section of Sundance formation on Trail Creek, Wyoming. Morrison shales. Teet. Samples. Massive gray sandstone 6 Gray sandstone, fossiliferous 1 1 Soft, gray sandstone _ 6 Hard, gray sandstone, very fossiliferous 1 2 Greenish sandy shale 30 Hard, thin-bedded, gray sandstone, containing fossils in upper part 6 3 Dark-gray limestone, fossiliferous 1 4 Greenish sandy shale ; belemnites throughout 50 5 Greenish-gray massive sandstone '. 4 Gray calcareous sandstone 6 6 Light-green shale, fossiliferous 6 7 Dark-green sandy shale 20 Green sandy shale, containing fossils _ 60 8 Greenish gray sandy shale, capped by a layer of fossiliferous limestone 6 9 Red sandy shale, containing a thin band of oolitic fossiliferous limestone 2 10 Compact gray limestone 1 Alternating layers of red and gray sandy shale, containing thin layers of gypsum 50 Gypsum 1 Gray thin-bedded 'limestone, weathering white 1 Gypsum, containing layers of red shale near top 6 Green shale, capped by a thin layer of fossiliferous limestone 2J 11 Gypsum , SJ Compact gray limestone, oolitic, fossiliferous 1§ 12 Green shale with banas of oolitic limestone 2 Green shale 4 Thin-bedded, gray limestone 1 Green shale ^ 1 Gypsum 4 Green sandy shale, capped by a thin layer of dark-gray limestone 12 Gray thin-bedded limestone, fossiliferous 3 13 Green sandy shale with a fossiliferous limestone layer at base 2^ 14 Green sandy shale, containing red layers 3 Alternating layers of green shale and white gypsum 4 . Dark-green fissile shale 5 Thin-bedded, light-colored limestone, fossiliferous 1 J 15 Alternating layers of red and green shale 1§ Dark rust-colored limestone, fossiliferous 16 Alternating layers of red and green sandy shale 1 J Gray limestone, containing fossils 17 Green shale, containing thin layers of light-gray limestone resting on Chugwater 3^ 322 The fossils from this locality have been examined by Mr. T. W. Stanton, and his report is here given. "The marine Jurassic fossils from Trail Creek, collected from many beds in a local section, all belong to one fauna, which is the same that occurs in Yellowstone National Park and the Black Hills." The fossils are listed below : STRATIGRAPHY — JURASSIC ROCKS. 23 Fossils from Sundance formation on Trail Creek, Wyoming. Lot 1. Pentacrinus asteriscus M. & H. Lot 11. Nerinea sp. Ostrea. Neritina (?) sp. Eumicrotis curta Hall. Two to three undetermined bivalves. Lot 2. Ostrea sp. ' Lot 12. Modiola sp. Pleuronya (?) sp. cf. P. subellipticus M. & H. Cyprina (?) sp. Belemnites densus M. & H. Lot 13. Trigonia americana Meek. Lot 3. Ostrea sp. Trigonia montanaensis Meek. Belemnites densus M. & H. Trigonia conradi M. & H. Lot 4. Camptonectes. Astarte sp. Ostrea. Belemnites densus M. & H. Undetermined small bivalves. Lot 5. Ostrea. Lot 14. Modiola sp. cf. M. pertenuis M. & H. Camptonectes bellistriatus. Lot 15. Modiola sp. Belemnites. Trigonia conradi M. & H. Lot 6. Ostrea sp. Trigonia elegantissima Meek. Eumicrotis curta Hall. Nucula sp. Lot 7. Belemnites densus M. & H. Several undetermined bivalves. Lot 8. Pentacrinus asteriscus M. & H. Lot 16. Ostrea strigilcula White. Serpula sp. Modiola sp. Gryphsea calceola var. nebrascensis M. & H. Camptonectes. Lot 9. Pentacrinus asteriscus M. & H. Several undetermined small bivalves. Ostrea strigilcula White. Lot 17. Gryphsea calceola var. nebrascensis M. & H. Camptonectes sp. Trigonia elegantissima Meek. Abundant. Lyosoma powelli White Astarte meeki Stanton. Lot 10. Oolite; no determinable fossils. Tancredia sp. Modiola sp. Bighorn Mountain region. — In the vicinity of the Bighorn and Sheep Mountain uphfts the Sundance formation is of variable constitution, changing so often that no two sections are closely alike. Soft greenish-gray sandstones predominate in its lower portion, and there is the usual thick mass of green shales above. Several hard sandstone and impure limestone layers occur at intervals, outcropping as prominent ledges, which generally are highly fossiliferous. Some typical sections follow: Section of Sundance formation on ivest side of mouth of Trapper CreeJc, south of Shell, Wyo. Feet. Alternating brown sandstone and green shale 20 Dark-brown fossiliferous sandstone, hard, thin-bedded 12 Dark-green fossiliferous shale with thin-bedded sandstone at base 115 Light-green sandy shale 50 Light-colored sandy clay 3 Dark-maroon sandy clay 2 Green sandy shale with numerous small oysters 20 Gray sandstone 1 Green shale on red beds 20 243 24 GEOLOGY AND WATER EESOURCES OF BIGHORN BASIN. Section of Sundance formation on Alkali CreeTc, Wyoming. Morrison. Peet. Green shale 25 Green thin-bedded sandstone _ 5 Brown fossiliferous sandstone 6 Green shele with belemnites and oysters 115 Thin-bedded gray limestone 16 Green shale on red beds 75 242 Section of Sundance formation on Horse CreeTc, 5 miles north of Sliell, Wyo. Morrison shales. Peet. Brown sandstone, hard at base, soft at top, very fossiliferous 25 Soft greenish-brown sandstone 25 Green shale, many fossils, belemnites at base, large oysters above SO Dark-brown and light-gray sandstones alternating, no fossils 20 Light-gray sandstone 25 Green shales, very fossiliferous 38 Brown sandstone, fossiliferous 1| Light-brown sandstone, fossiliferous 2 Green shale, fossiliferous, on maroon shale of Chugwater 12 198^ The fossils collected at this last locality have been examined by Mr. T. W. Stanton, who reports the following forms: Fossils from Sundance formation, Horse CreeTc, Wyoming. Lots 1-2. Ostrea strigilecula White. Lot 5. Ostrea engelmanni Meek. , Lot 3. Dosinia jurassica Whitfield? Belemnites densus M. & H. Lot 4. Gryphaea calceola var. nebrascensis M. & H. Lots 6-7. Ostrea sp. Eumicrotis curta Hall. In the southern part of the district, along the base of the Owl Creek Mountains, the formation has a thickness of about 194 feet. A section taken on Owl Creek near Watson's ranch is given below: Section of Sundance formation near Watson's rancTi on Embar road just north, of Owl CreeTc, Wyoming. Feet. Green sandy shale 2 Fine-grained, hard, buff limestone. This limestone breaks at right angles to the bedding plane in a smgular way, so as to give the ledge the appearance of being frost-cracked or minutely spalled 2 Thin-bedded greenish-gray sandstone 4 Green sandy shale 20 Alternating layers of greenish-gray sandstone and soft greenish sands 30 Green sandy clay with many belemnites and a few oysters 40 Gray calcareous sandstone 2 Green sandy clay 20 Gray sandstone 4 Alternating layers of green, soft, sandy shales and hard, greenish fossiliferous sandstone 70 194 STRATIGRAPHY. 25 CRETACEOUS SYSTEM. MOERISON FORMATION. General relations. — The Morrison formation is extensively developed along the eastern, western, and southern sides of the Bighorn basin and shows considerable change in character throughout the area. It is composed of soft sandy shales and clays alternating with layers of massive sandstones, all of fresh-water origin. The clays have the characteristic joint-clay structure, and the sandstones are fine- grained. The prevailing color is pale green with shades of red, maroon; and purple, and in the upper part of the formation the clays are very dark. The thickness varies from 130 to 382 feet. The formation is generally exposed in a narrow band on the inner rim of a low ridge formed by the harder overlying sandstones of the Cloverly. Along the base of the Bighorn Mountains, from the Montana line southward nearly to the head of Beaver Creek, the dips are steep, and the outcrop is relatively narrow, but south of Beaver Creek, owing to decreased dips, it is much wider. Around the Sheep Mountain uplift the outcrop zone is generally narrow. Farther west, on both sides of Rattlesnake Mountain and along the front of the Absaroka and Bear- tooth ranges, the outcrop rarely exceeds one-fourth mile in width. Absaroka and Owl Creelc mountain region. — Along the western side of the basin the Morrison formation is about 150 feet thick. It consists of alternating layers of gray fine-grained sandstone and dark-gray sandy shale. Near the base there is often a thin bed of gray limestone. In one locality near the southern end of the Cedar Mountain anticline a deposit of gypsum 8 feet thick was observed near the top of the formation. Three typical sections along the western and southern sides of the Bighorn basin are as follows: Section of Morrison formation on Trail Creek, northwest of Cody, Wyo. Cloverly formation. Feet. Green, sandy shales alternating with green clay containing thin layers of gray limestone throughout 100 Massive, fine-grained, gray sandstone lying on Sundance formation _ 30 130 Generalized section of Morrison formation south ofClarTc Fork Canyon, Wyoming. Cloverly formation. Feet. Massive greenish-gray sandstone _ 80 Greenish clay 60 Dark-gray limestone 1 Dark-gray sandy shale lying on Sundance formation ■■ 20 161 Section of Morrison formation near Watson's ranch on Ernbar road just north of Owl Creek, Wyoming. Feet. Massive gray sandstone 10 Concealed material, evidently soft and sandy 125 135 26 GEOLOGY AND WATER RESOURCES OF BIGHORN BASIN. Bighorn Mountmn region. — In the Bighorn Mountain region the Morrison forma- tion consists of clay,, fine sandstone, and sandy shale. The colors of the shale vary from gray and greenish-gray to maroon and purple, with some dark layers, especially toward the top. The sandstones are mostly of light-gray color and often contain large fossil saurian bones. South of^ Shell and, southeast of Cloverly there is a massive light-colored sandstone near the base. South of Shell this bed is 20 feet thick and moderately hard, and is separated from the Sundance formation by red- dish shale and overlain by. massive, greenish, sandy clay. Southeast of Shell the sandstone is of light-buff color, is 40 feet thick, moderately coarse grained, and has lenses of conglomerate near the top. In places the sandstone is bright red, resembling some of the sandy members of the Cloverly formation. A typical section of the formation on Alkali Creek follows: Section of Morrison formation on Alkali Creek, Wyoming. Feet. Pale-green massive shale overlain by Cloverly sandstone .' 50 Thin-bedded gray sandstone, brown on surface . . 15 Pale-green massive shale 5 Blue-black shale 10 Maroon massive shale 10 Variegated massive shale _ 45 Thin-bedded gray sandstone 6 Variegated massive shale, drab, purple, and maroon. . _ 65 Pale-green to white sandstone ■. 6 Pale-green and maroon massive shale 85 Pale-green massive sandstone 45 Red sandy shale lying on Sundance formation 40 CLOVERLY FORMATION. General relations. — Overlying the Morrison formation in this region are sand- stones for which Mr. Darton has proposed the name Cloverly formation, from the extensive exposures in the vicinity of Cloverly. The formation consists of alternat- ing layers of sandstone and sandy clays, which are generally highly colored; buff, light green, maroon, and bright red prevail. The materials comprising the forma- tion are very changeable. In places the sandstones are locally hard and have resisted erosion so as to stand out in typical hogback ridges; in other localities the entire succession is so soft that it weathers in low slopes and can be traced only by the bright colors which some of the members exhibit. In some localities it is possible to recognize a basal coarse-grained sandstone lying unconformably upon the Morrison shales, not unlike the Lakota sandstone of the Black Hills region, and above this a highly colored shale, overlain in turn by a massive sandstone resembling the Dakota. The basal sandstone of the succession is often very coarse- grained and pebbly and is very different in character from the underlying fine- grained sediments of the upper part of the Morrison formation. Frequently the contact between the formations is marked by an unconformity showing distinct channeling. The sandstone of the Cloverly formation is from 10 to 50 feet thick, and the thickness of the formation varies from 100 to 300 feet. Coaly shale and coal some- STRATIGEAPHY CRETACEOUS BOOKS. 27 times occur associated with the basal sandstones. The area of Cloverly outcrop in the district is about equivalent to that of the underlying Morrison formation. AisaroTca Mountain region. — West of Rattlesnake and Cedar mountains the dips are steep and the Cloverly formation outcrops as a very narrow zone, rarely exceeding one-eighth mile in width. Along the eastern side of Rattlesnake Moun- tain it caps the prominent ridge between Trail and Dry creeks, and at the southern end of this ridge it extends across a saddle, through which Dry Creek passes, and joins the area exposed by the low anticline on Cottonwood Creek. Along the base of the Absaroka Range the Cloverly formation occupies a narrow but continuous zone, extending from Black Mountain to the Montana line. In the vicinity of Clark Fork Canyon its thickness is about 300 feet. South of Cody the Cloverly formation consists of a basal coarse-grained sand- stone, often pebbly, about 50 feet thick. It is overlain by softer gray sandstones of undetermined thickness. ' Above this occurs a layer of highly colored clay, which contains near the middle a band of dark shale. Overlying the clay is a top sandstone member, which is succeeded by the rust-colored sandstone of the base of the Colorado formation. Bighorn Mountain region. — Along the base of the Bighorn and Pryor mountains and around the rim of the Sheep Mountain uplift the outcrop of the Cloverly is generally narrow, but widens somewhat on the high ridge east of Frannie, along the upper part of Alkali Creek and in the vicinity of Cloverly. South of Shell Creek the formation rises with the upward pitch of the S3mcline southwest of Shell and outcrops in an irregular zone extending east and west for several miles. In the anticline east of Sheldon's ranch it appears on the northern side of Shell Creek for a short distance, pitching down to the north under the basal shales of the Colo- rado formation. Along the foot of the mountain north of Cloverl}^ it dips steeply for some distance, but on Alkali Creek and about Cloverly and farther south it dips verj^ gently to the west. In the lower portion of Beaver Creek Valley the rocks are covered by alluvium, except for a small sandstone outcrop on the eastern side near the mouth of the creek. There are extensive and characteristic exposures in the vicinity of Cloverl}'', the type locality. Here the rocks are usually gva,j to buff sandstone below and massive shale or hard sandy clay above, their thickness varying from 50 to 150 feet. East and north of Cloverly the formation consists of sandstone which outcrops extensively in cliffs. It is a buff-colored rock in massive beds, mostly of moderately coarse-grained material. It is here 50 to 125 feet thick. West of Cloverly the middle and lower portions of this sandstone change to a maroon color, and some clay is intermixed with the sand. Section of Cloverly formation 1'^ miles west of Cloverly , Wyo. Feet. Light-buff sandstone overlain by Colorado formation 10 Tan-colored sandstone 10 Maroon clay 4 Reddish, tan-colored sandy clay _ 10 Drab sandy clay ^ 10 Deep-maroon sandy clay _ . . 20 Hard, tan-colored sandstone 3 Deep-maroon to purple variegated clay 12 11774— No. 53—06 3 28 GEOLOGY AND WATER RESOURCES OF BIGHORN BASIN. Feet. Lenses of maroon sandstone 3 Deep-maroon sandy clay 20 Olive-green, soft, cross-bedded sandstone, with hard layers lying on maroon and drab-gray Morrison shale 10 122 Owl Creek Mountain region. — Along the base of the Owl Creek Mountains the Cloverly formation is extensively exposed, and a small outcrop oGCurs at the base of the Shoshone Mountains on Gooseberry Creek near the southern end of a small anticline east of Sunshine post-office. It outcrops in a zone of varying width around the base of the larger anticline at Thermopolis and in a similar way encircles a smaller anticline lying to the east in range 93. It occupies the central portion of a small uplift which lies mainly on the east side of Bighorn River, opposite the mouth of Owl Creek, and other exposures occur along the southern margin of the district in ranges 95, 96, and 97. In ranges 98 and 99, township 43, the outcrop is narrow, owing to steep dips, and to the west, near the head of a small branch of Cottonwood Creek, it disappears under the volcanic rocks. On the western rim of the Thermopolis anticline, near Watson's ranch, the Cloverly formation has a thickness of 225 feet and exhibits the following members : Section of Cloverly formation mcr Watson's ranch on Emhar road, just north of Owl Creek, Wyoming. Feet. Gray massive sandstone of uneven hardness 100 Concealed in part, but at another exposure consists of maroon sandy shale at base, merging upward to a dull greenish gray, with an occasional harder layer of sandstone _ 100 Brown massive sandstone with thin-bedded layers 25 225 COLORADO FORMATION. General relations. — The Colorado formation is well developed in the Bighorn basin, being represented by beds ranging from 1,400 to 2,000 feet in thickness, but the Greenhorn limestone, which is so prominent in the vicinity of the Black Hills and along the Rocky Mountain Front Range, does not appear. The Colorado formation is exposed in a wide area in the northeastern portion of the basin, and from Shell Creek southward its outcrop varies from 4 to 6 miles in width. It is exposed in a wide area on both sides of Rattlesnake Mountain, but farther north, along the base of the Absaroka and Beartooth ranges, the beds dip steeply and the outcrop is very narrow. Small areas of the formation are exposed along the axes of anticlines east of Sage Creek, at intervals along the base of the Shoshone Mountains from Fourbear to the Antler ranch, on the divide between Rawhide Creek and Gray Bull River north of Pitchfork ranch, and on Wood River and Gooseberry Creek near Sunshine post- office. In the Owl Creek Mountain Region it occupies an area 3 to 6 miles wide, extending along the base of the mountains from a point west of Embar to the middle of range 92. South of Cottonwood Creek there is an anticline exposing 5 or 6 square miles of Colorado formation. For further details concerning the distribution of the formation see the geologic map. (PI. Ill, pocket.) STEATIGBAPHY CEETAOEOUS ROCKS. "I'd Pryor Mountain region. — On the southern side of Pryor Mountain, 5 miles north of Cowley, the Colorado formation consists of a basal member of rusty brown sandy shales, 200 feet thick, overlain by 500 feet of very black shale, in the upper part of which occur several horizons of a light-colored clay known as bentonite. Imme- diately above this there are about 150 feet of hard, lighter gray shale and sandstone, constituting the Mowry beds. Next above are about 300 feet of light-gray shales alternating with sandy beds. These shales are capped by 60 feet of gray, coarse- grained, cross-bedded sandstone, often water bearing, which in turn is overlain by shales 200 feet thick, containing concretionary bands and constituting the uppermost member of the formation. Ahsaroka Mountain region. — Along the western side of the Bighorn basin the Colorado formation is represented by about 2,000 feet of beds, of which the lower 100 feet consist of rusty brown sandstone, alternating with gray sandy shale. This basal member is usually overlain by 200 to 300 feet of very black shale, in the middle of which occurs a brown sandstone 20 to 30 feet thick. Above the shale are several hundred feet of lighter colored fissile shale, alternating with massive beds of gray sandstone that contains in its upper portion a thin deposit of coal. Above this there are 200 to 300 feet of dark shale with iron concretions, forming the uppermost member of the formation. The sandstones of the Colorado formation are sometimes coarse grained and in one locality, on Cottonwood- Creek south of Heart Mountain, were observed to contain thin layers of pebbly conglomerate. / Bighorn Mountain region. — On the lower lands bordering the Bighorn Mountains from Shell Creek northward there is a wide area of Colorado shales in a shallow syn- cline or basin whose western side rises in Sheep Mountain. In the vicinity of Cloverly the Colorado shales are about 1,200 feet thick. The predominating rock is black fissile shale, with thin sandstone alternations. The salient features of the formation west of Cloverly are as follows : At the base, lying on buff sandstone of the Cloverly formation, are about 100 feet of dark-gray to black shale, with thin brown sandstone layers, weathering to a rusty color. The shales usually begin abruptly on top of the Cloverly formation, but apparently there is no unconformity. Concretions of globular shape, averaging an inch in diameter, occur in a few feet of the lower shales, about 60 feet above the base. The concretions have a radiating structure and consist mainly of phosphate of lime, having the crystalline form of marcasite, the mineral of which the concretion originally consisted. Over- lying this basal rusty succession are about 200 feet of black fissile shale, capped by 25 feet of hard sandy shale containing layers of thin-bedded dark sandstone, which represents the Mowry beds of the eastern side of the Bighorn Mountains. These beds contain many fish scales and weather to a light-gray color. They merge upward into 30 feet of dark shale, overlain by alternating shale and sandstone, capping a high ridge. The sandstone layers are from 6 inches to 3 feet thick and are of dark-gray color. This succession may represent the upper part of the Mowry beds. At its top there is a bed of light-colored sandstone about 10 feet thick. Above this there are several hundred feet of dark-colored soft shale containing a few black concretions and in its upper portion several sandstone layers. At the top there are 100 feet of sandy buff-colored shales, with brown concretions, containing Metoicoceras 30 GEOLOGY AISTD WATER EESOURCES OF BIGHORN BASITST. gibhosus, M. whitei Hyatt, and Inoceramus fragilis. This is believed to be the top of the formation. The calcareous shales and in].pure chalks which characterize the upper member of the Colorado formation elsewhere have not been distinctly recognized in the Big- horn basin. Along the base of the Bighorn Mountains light-gray shales, somfetimes calcareous, lie immediately below the Pierre shale and may represent deposits of Niobrara age; but no fossils have been found in these beds. On the western side of the basin, in the vicinity of Cody, black shales, underlying the Pierre shales, contain fossils belonging to a horizon near the top of the Colorado formation. The following forms, identified by Mr. T. W. Stanton, were collected from the southern bank of Shoshone River 1 mile northeast of Cody : Fossils from the south harik of Shoshone River, Wyoming. Inoceramus acutilineata Stanton ( ?) . Corbula. Inoceramus sp. Turritella. Crassatella. Baculites asper Morton (?). Cardium. Baculites of. B. anceps Lam. Pholadomya papyracea M. & H. Scaphites ventricosus M. & H. Sandstone dikes. — A number of sandstone dikes cut the Colorado shales along the lowlands bordering the Bighorn Mountains. These are formed of sand that has been forced up, while wet, from underlying sandstones, through crevices in the overlying shales, probably by the pressure of aheavy load of overlying strata. These dikes vary from 6 to 10 feet in width and are composed of material similar to the Cloverly sand- stone. They can sometimes be traced for a mile, generally in a direction at right angles to the trend of the mountains. A small dike of this character occurs on the divide between Bear and Alkali creeks, about 6 miles west-northwest of Cloverly, and others traverse the shales a short distance west of the northern end of Sheep Mountain. PIERRE SHALE. Character and tJiickness. — In the Bighorn basin this formation is represented by lead-gray sandy shales containing occasional concretions, which are often fossihfer- ous. The shales are ferruginous and on weathering generally assume a yellowish color. Along the eastern side of the basin the formation is probably less than 1,000 feet thick, while at Cody and in the vicinity of Heart Mountain a thickness of 2,000 feet was measured. The shales of the Pierre formation are soft and weather uni- formly, often giving rise to strike valle5^s between the high sandstone ridges of the underlying and overlying formations. A number of topographic depressions in the Laramie and associated formations, which are due to eroded anticlines, expose Pierre shale in their central portions. Distribution. — The Pierre shale spreads out over a wide district along Sage and Dry creeks, in the neighborhood of Cowley, but to the south, on the west side of Sheep Mountain, owing to steeper dips, it outcrops as a narrow band, continuing thus to Basin. East of Basin a broad, shallow syncline, 8 to 10 miles wide, in Pierre shale, extends nearly to Bonanza, and from here to the southeast corner of the basin the outcrop zone varies in width from 2 to 4 miles. On the head of No Water and Kirby STKATIGEAPHY CRETACEOUS "ROCKS. 31 creeks the dips are low, and the formation covers a considerable area, which narrows somewhat along the northern side of the Thermopolis anticline. From Watson's ranch on Owl Creek, northwest to beyond Cottonwood Creek, a number of gentle folds in the beds occur, materially increasing the surface area of the formation. Between Cottonwood Creek and Gray Bull River a number of anticlines expose Pierre shale in their central parts, and from Sunshine post-office to Cedar Mountain it occupies an area from 4 to 10 miles wide, lying at the base of the Shoshone Range. South of Oregon basin there is an area of Pierre shale comprising several square miles, but from Wiley's ranch northward to the Montana line the outcrop zone tarely exceeds a mile in width. LAEAMIE AND ASSOCIATED FORMATIONS. General statement. — The Laramie and succeeding formations in the Bighorn basin have a thickness varying from 5,000 to 7,000 feet, consisting of sandstones, shales, and clays, with seams of coal and coaly shales. The group is extensively exposed throughout the northeastern portion of the Bighorn basin. Along the western side of Bighorn River, from Basin nearly to the head of Little Dry Creek, it is partly covered by the overlying Wasatch beds, but from the latter point north- westward to the Montana line its outcrop gradually widens. Southward from Basin the dips are moderately steep, and the formations occupy an area 3 to 5 miles wide, which continues to Bud Kimball Draw. Across the southeast corner of the basin the area expands somewhat, and to the west, across the southern side of the district, it averages about 6 miles. In the southwestern part of the basin this group is exposed over an area 10 to 12 miles wide, which in some places is covered by the Wasatch and in others sufficiently eroded to expose the underlying Pierre. In the vicinity of Sunshine post-office there is an outlier of so-called Laramie covering several square miles. On both sides of Sage Creek east of Cody there is an extensive outcrop of Lara- im'e, etc., due to a low, broad, anticlinal fold, which passes through Oregon basin. North of Shoshone River the outcrop occupies a relatively broad area, which is greatly contracted in its northern extension, owing to an increase in dips and a decrease in the thickness of the beds. On Line Creek the entire series apparently has a thickness of less than 1,200 feet. Stratigraphy. — The sandstones of the group are generally gray, but a variable amount of iron gives rise to local coloring. Throughout the lower portion the sand- stones are usually fine grained and massive and the beds are from 1 to 75 feet thick, but 25 to 30 feet is a most common measure. Where shaly intercalations predomi- nate the sandstone generally exhibits considerable variation in character. Sand- stone concretions frequently occur which vary in size from 1 to 10 feet in diameter; their form is usually elongated, with rounded edges, although spherical and lens- shaped concretions abound. In the upper part of the group the sandstones are coarse grained, containing numerous cross-bedded, pebbly, conglomerate layers, some of which attain considerable thickness. At the base of the upper half there is a conglomeratic horizon, which, owing to its increased hardness, gives rise to a hogback ridge. This ridge crosses Shoshone River near the mouth of Sage Creek. From this horizon to the base of the overlying Wasatch formation the conglomeratic 32 GEOLOGY AND WATER EESOURCES OF BIGHORN BASIN. layers recur in the sandstones at frequent intervals. The intercalated shales are mainly gray, but often contain a sufficient amount of carbonized wood particles to impart to the beds a lignitic character. Age of the formations. — As to the age of the formations comprising tliis group there is some uncertainty, for no distinctive fossils were found, and the stratigraphic relations to other regions were not determined. Along the eastern side of the Bighorn Mountains the sandstone at the base of this group, which has been desig- nated the Parkman formation, contains fossils characteristic of the Fox Hills sand- stone, but in the Bighorn basin from the supposed equivalents of these beds fossils appear to be absent. Its stratigraphic position indicates that the entire succession probably represents the Fox Hills or Parkman and Laramie formations and possibly in its upper portions the Fort Union beds. The Livingston formation, which is extensively developed in Montana, may also be represented in the upper beds. Supposed Fox Hills sandstone. — The Fox Hills sandstone has not been definitely recognized in the western portion of the Bighorn basin. At the base of the Laramie formation is a succession about 300 feet thick of massive gray to buff sand- stone, with several layers of harder, rust-colored, concretionary sandstone. Litho- logically these beds resemble the Fox Hills or Parkman sandstone on the eastern side of the Bighorn Mountains. On Polecat Creek, about 5 miles northeast of Gar- land, the following fossils were collected from sandstones overlying the Pierre shale: Fossils from Polecat Creek, Wyoming. Cardium speciosum M. & H. Baculites sp., imperfect casts. Mactra sp., small cas:s. Tooth of shark. The above species have a considerable vertical range and, according to Mr. Stanton, may occur in the Judith River beds as well as in the Fox Hills. On the geologic map these sandstones are included with the overlying Laramie and associ- ated formations. TERTIARY SYSTEM. VOLCANIC AND ASSOCIATED SEDIMENTARY ROCKS. The Tertiary deposits of the Shoshone Mountains have not been studied in detail in connection with the present investigation. The rocks consist largely of volcanic breccias and lava flows interbedded with sandstones and shales which have a thickness of many thousand feet. They overlap unconformably all the older rocks, outcrop- ping along the western side of the Bighorn basin, as shown in the cross sections (PL IV, p. 8). On the northern side of the Middle Fork of Owl Creek, near its head, fossil leaves were discovered by Mr. N. H. Darton, which have been identified by Mr. Knowlton, as follows : U. S, G EOLOGICAL SURVEY PROFESSIONAL PAPER NO. 53 PL. X ■ ■— -^ •^':ief:"wrfi.-"-"^ ■ ■ _ _ - ■ >^;-%«l^^ ■ I^^H^^ - „ . HB^^Bi^«>.^ *>.■* ■ •• - • ^^^^H H^^^^Bfer ■ . < - -.•- ' • •- .-i.v^Ai'^^ i^^^l ^■^^S*<.- - .^.,4;., . l^^l ?i>if. ■■ . *'';-^-T-''"'*.*>"?'^.4-. • -'■"-i ^^^H ^I^hKx' ' '. --■'«* ~~ ..:-^^- ' t'^ - '" " -■-"','; ■" :'^"';^?t;^ I^^^H ■^^7'if«-<-.V-">^* •■'•■'■• I 1 A. SHOSHONE RIVER IN VICINITY OF CORBETT, WYO. ..SHM^ :?;-iX't~-"v;vS|; Wasatch c o n g I o m e r a t _ ^ ^„\ ^„ „ , >>mm^-^m}m. ■ sandstone -^\ > BASAL WASATCH CONGLOMERATE LYING U NCON FORM ABLY ON LARAMIE SANDSTONE. At head of Dry Cottonwood Creek. 8TEATIGRAPHY TERTIARY ROCKS. 83 : Fossils from Middle ForTc of Owl Creek, Wyoming. Equiseuum sp., one fragment. Sapindus obiusifolius Lesquereux. Two or three Lygodium kaulfusii Herr (L. neuropteroides Lesq.). examples. Abundant. Cinchonidium, cf. C. ovata Lesquereux. Two or three Populus cuneata Newberry. Abundant. examples. Populus glandulifera Herr. Abundant. Carpi^es sp. Populus zaddachi Herr. Abundant. From a slightly higher horizon the following forms Quercus olafseni Herr. Two examples. W( Platanussp.? Several fragments of large leaves. Fragments of the rays of a large palm. Aralia whitneyi Lesquereux. Several fragments. Ficussp.? Aralia notata Lesquereux. Several fragments. Acer, cf. A. bolanderi Lesquereux. One small leaf. Araha, cf. A. radiata Ward. Two examples. WASATCH FORMATION. Character and thickness. — The Wasatch formation consists of alternating layers of sandstone and clay, with an occasional bed of conglomerate. The sandstone predominates, mostly as a soft, fine-grained, massive rock in beds which vary in thickness from 10 to 40 feet. The thicker sandstone members occur near the base of the formation, while those higher up are not only thinner, but less pure, approach- ing sandy clays. The prevailing color is gray, although rust-colored bands are not infrequent. The clays are sandy and contain numerous small concretions, which are sometimes fossiliferous. They are generally gray, but strata of red, maroon, and green abound, giving to the whole a banded appearance. Red colors predomi- nate, and often serve as a means of distinguishing the formation from the under- lying Cretaceous sandstone. The lower part of the Wasatch is conglomeratic, comprising 400 to 600 feet of alternating layers of conglomerate and red clay. The conglomerate is composed of pebbles derived mainly from Paleozoic sediments, with only a small percentage of pre-Cambrian material. The formation has a thickness of 1,500 to 2,500 feet and lies unconformably upon the preceding Cre- taceous deposits (PI. X, i?). Distribution. — The Wasatch has a more extensive outcrop than any other formation in the district", occupying a broad area in the central part of the basin, which narrows rapidly to the northwest. It constitutes the prominent McCuiloch Peak, extends entirely around the base of Heart Mountain, occupies the low divide between Bighorn and Clark Fork basins, and gives rise to a number of prominent peaks along the base of the Beartooth Mountains from Clark Fork to the Montana line. It continues from Gray Bull south to beyond Bighorn River in the region of the Honeycombs. Along Dry Creek, Shoshone River, and Clark Fork the forma- tion is covered by broad areas of Quaternary deposits. The Wasatch beds contain an abundant mammalian fauna. The fossils are generally found in the clays, although their occurrence in the sandstones is not ^uncommon. The best collecting grounds observed were on the badlands slopes northeast of McCuUoch Peak, but fossils were found all along the divide between Shoshone River and Dry Creek. These deposits have been studied jointly by Messrs. Osborn and Wortman with reference to their fossil mammalia, and they have been found to be the same as those that characterize the Wasatch formation in regions southwest of this area. 34 GEOLOGY AND WATER RESOtJRCES OF BIGHORN BASIN. Capping some of the highest areas in the central part of the Bighorn basin, especially that part Ipng south of Gray Bull River, are brown, leaf-bearing, sandy shales and gray sandstones, which have a total thickness of about 600 feet. Thin coal seams sometimes occur in these beds, and in one locality on the southern side of Tatman Mountain some prospecting has been done in a seam which has a thickness of about 18 inches. A number of fossils were collected from the sandstones of this formation in the vicinity of Squaw Buttes. These have been examined by Dr. T. W. Stanton, who makes the following report: The small collection contains many internal casts of fresh-water fossils belonging to the genera Unio, Viviparus, and Goniohasis. Of the last named there are imprints of the exterior which permit identification with G. ienera Hall, an Eocene species. The Unio has about the size and proportions of U. haydeni Meek and the Viviparus resembles V. wyomingensis Meek, but in neither case can specific identification be positively made with such material, as there are Laramie species so closely resembling these that they could not be dis- criminated from the casts alone. I think that the horizon is Eocene, but I am unable to determine from these fossils whether it is Wasatch or Bridger. These beds are extensively exhibited in Tatman Mountain and Squaw Buttes. They have been represented with the Wasatch on the geologic map. QUATERNARY SYSTEM. General statement. — During the Quaternary period erosion preponderated throughout this general region, especially in the higher mountainous portion. Most of the products of this erosion, however, have been carried away, but some materials remain, derived chiefly from the high mountains in the western part of the area. The deposits are confined mainl}^ to the northern part of the Bighorn basin, where they occur as extensive gravel terraces capping the high divides and bordering the larger streams. Deposits of three different periods are recognized, early and late terrace gravels and alluvium. Early terrace gravels. — The early terrace deposits cap the liigh plateaus between the larger streams in the central portion of the basin. The most extensive of these terraces are on the high plateau northeast of Ralston, on the highland between Dry Creek and Gray Bull River, extending from the western end of Meeteetse rim nearly to Bighorn River and capping Tatman Mountain. They are composed of alternating layers of gravel, sand, and silt, having a thickness of 30 to 40 feet, and in places are underlain by light-colored sandy clays, which may be of Tertiary age. Later terrace gravels. — The later terrace gravels (PL XVI, A, p. 60) border all the larger and many of the smaller streams, especially in the northern part of the district. The most extensive of these deposits lie along the northern side of Shoshone River from Garland to Eaglenest. Between Ralston and Corbett they occupy a width of about 2 miles along the western side of the river, and from there to Shoshone Canyon they occur in terraces on both sides of the river. Later terrace gravels of no great extent occur along Bighorn River and its principal tributaries to the south. No Wood and Owl creeks, and remnants of these deposits occur on Tensleep, Paintrock, and Shell creeks. Along Clark Fork and Pat O'Harra Creek there are extensive areas of the later terrace gravels. The material in the vicinity of Clark consists mainly of coarse gravel and bowlders, with a small amount of sand and silt. STEATIGEAPHT QUATEENAEY EOCKS. 35 Alluvium. — The alluvial deposits of the Bighorn basin exhibit some diversity of character, especially along the smaller streams. The alluvium along Bighorn River is of varying width, rarely exceeding 1 mile, and extends nearly across the area described in this paper. There are places throughout its course where the river flows through deep, narrow gorges in which no alluvium has been deposited. These are in Black, Sheep, and Bighorn canyons. The alluvial material is light gray, very sandy, and has a thickness of 25 to 40 feet. Shoshone River has consid- erable fall between Shoshone Canyon and the Garland bridge, and is in consequence a cutting rather than a depositing stream, but below this point the fall diminishes and the stream is bordered on both sides by Avide alluvial flats. Here the material consists of a fine gray sand mixed with decayed vegetation and usually containing a large amount of black magnetic sand. Dry Creek Valley has a light-colored sandy wash, derived chiefly from the soft sands and clays of the Wasatch formation. Gray Bull River and its principal tributary. Wood River, are bordered by narrow alluvial deposits, which generally contain more or less coarse material brought down by the mountain streams during the flood seasons. Below Fenton the alluvial flat widens considerably and continues thus to a point below Otto, beyond which it extends as a relatively narrow band to Bighorn River. Most of the streams in the northwestern part of the basin, including Clark Fork, have narrow alluvial deposits. Along this river the material is coarse and contains bowlders suggestive of sediments derived from a glacier. The alluvium of the smaller streams is of local origin, and varies in character with the formations which the streams traverse. Newmeyer and Paint creek deposits contain much detritus derived from the Chugwater red beds on the higher slopes to the west. The alluvial materials on Pat O'Harra Creek, below the mouth of Skull Creek, have a dull-gray color and consist largely of wash from the Colorado and Pierre shales and from the more sandy cretaceous beds overlying them in the vicinity of Heart Moun- tain. On Trail Creek northwest of Cody the alluvium is composed mainly of red wash from the Chugwater formation. The streams in the higher portion of the Bighorn Mountains flow in deep canyons or narrow valleys, where the conditions are imfavorable for the deposition of alluvium. In the lower lands farther west, which are underlain by shales and soft sandstones, wide valleys have been cut by the streams and the alluvial deposits are more exten- sive. The principal areas of alluvium lie along Shell Creek, occupying a belt about 1 mile wide. The deposit is from 10 to 40 feet thick. Along Beaver Creek lie narrower alluvial flats which, below the mouth of Red Gulch, attain a width of about a quarter of a mile. In its course through the red beds Trapper Creek traverses a narrow alluvial valley which joins that of Shell Creek above Shell. Along Beaver Creek and in the valley south and east of Shell the deposits contain much red detritus derived from the Chugwater red beds. In their lower courses Paintrock and Ten- sleep creeks have narrow alluvial valleys, which are very fertile. Alluvial deposits of a more or less local nature occur on Dry, Dry Cottonwood, Gooseberry, Meeyero, and Owl creeks, and along the eastern side of Bighorn River on Earby, No Water, and No Wood creeks. The alluvium of the streams draining the central portion of the basin shows some local variation, but is generally light colored and sandy, being derived chiefly from the soft sands and clays of the Wasatch. 36 GEOLOGY AND WATER RESOURCES OF BIGHORK BASITST. and underlying Cretaceous formations. No Wood Creek in its upper course contains much red wash derived from the Chugwater red beds, through which it flows for several miles. STRUCTURAL GEOLOGY. General features. — The mountain ranges inclosing the Bighorn basin are pri- marily anticlinal uplifts more or less modified by erosion. In the Absaroka, Bear- tooth, and Shoshone ranges the erosion has been followed by the deposition of immense sheets of volcanic breccia, which are now deeply cut by the present streams. The Bighorn basin is essentially a broad structural valley which has been formed between two large anticlinal folds, the Bighorn Mountains on the east and south and the Beartooth, Absaroka, and Shoshone mountains on the west. Across the northern end of this valley, from Heart to Pryor mountains, extends a low anticlinal fold that separates the Bighorn and Clark Fork basins, and a number of minor flexures parallel to the larger uplifts occur along the outer rim of the inclosed valley. The details of the structure of the Bighorn basin are shown in PI. XI. Structure of the Bighorn- uplift. °- — The Bighorn Moimtains form a great anticline that is due to an uplift measuring many thousand feet, which begins in south-central Montana and extends southeastward and southward about 125 miles, into central Wyoming. It lifts a thick series of Paleozoic and Mesozoic formations high above the plains and, owing to the deep erosion of its crest, presents a central nucleus of pre-Cambrian granites from which sedimentary rocks dip at varying angles on each side. The most elevated portion of the uplift is in latitude 44° 30', where one of the granite summits, Cloud Peak, has an altitude of 13,165 feet, rising about 9,000 feet above the adjoining plains. The greatest vertical displacement of the strata, as indicated by the height at which the granite floor is now found, amounts to about 18,000 feet. For the greater part of its course, the anticline is relatively simple in shape, but there are numerous local variations in the steepness of its sides and the shape of its top, owing to the presence of extensive faults. In general, its eastern side is much steeper than the western, especially in the central portion of the uplift. In its northern part both sides are relatively steep and the top is remarkably flat. In the highest portion of the uplift, which is probably near Cloud Peak, the sedi- mentary rocks have been removed over a considerable area, and we can only con- jecture the form which the flexure would have if the eroded portions of the granite and the overlying sedimentary beds were restored. In this region there is apparently a long, uniform rise from the west, a similarly gentle grade downward to the east for some distance, and then the steep dips which are now found in the foothills on that side. The main uplift bears a number of subordinate flexures, the most notable one being east of Bald Mountain. It is an anticline rising about 2,500 feet on the northeastward dipping limb of the main anticline. A diagr^-m of the structure of the Bighorn Mountains^ and their southern extension, the Owl Creek Range, *= has been published by Mr. N. H. Darton. a This description of the structure of the Bighorn uplift is taken from the Bald Mountain folio, now in press, by Mr. N^H. Darton. b Geology and water resources of the Bighorn Mountains: Prof. Paper U. S. Geol. Survey No. 51. c Geology of the Owl Creek Mountains, Wyoming: Senate Doc. No. 119, 59th Congress, 1st session. STRUCTURAL GEOLOGY. 37 Structure of tTie Absaroka Mountains. — The Absaroka Mountains comprise that part of the western Rocky Mountain Front Range lying between Clark Fork and Shoshone River. This range extends in a north-south direction for a distance of about 80 miles, and has an average width of 50 miles. Only the eastern portion is iacluded within the area to which this paper relates. The structure of the Absa- roka Range is complex, but in general it is a broad anticlinal fold having a pre- Cambrian granite core, which to the east is bordered by a thick series of Paleozoic and Mesozoic formations dipping eastward with steep angles toward the Bighorn basin. These dips decrease rapidly toward the lower lands. Between Clark Fork and Shoshone River two important folds extend from the main range. The larger, com- prising Rattlesnake and Cedar mountains, diverges at an angle of about 20°, and the smaller, which constitutes Black Mountain, at a somewhat greater angle. The Rattlesnake Mountain uplift is a moderately broad anticlinal fold, with gradual slopes on the east and steep dips on the west. It lifts the Paleozoic strata about 8,000 feet above the horizon. In the deep canyon of Shoshone River the structure of the uplift is exposed down to and into the crj^^stalline rocks. The structure of the Rattlesnake Mountain uplift is shown in the cross sections on PI. IV, p. 8. South of Shoshone River the anticlinal bends sharply to the east, and, owing to rapidly decreasing dips, soon drops into a low arch which disappears near Frost ranch, on Sage Creek. The smaller fold projects from the main range at an angle of about 40°, and gives rise to Black Mountain. On the southern side of this mountain, at the head of Pat O'Harra Creek, the Tensleep sandstone and overlying Chugwater formation dip steeply to the southwest into a narrow syncline separating Black and Rattlesnake mountains. Across the northeast side of Black Mountain, there is a bold escarpment of Carboniferous limestone overlooking the steeply dip- ping Tensleep and Chugwater formations. About 6 miles east of Black Mountain, along the axis of the smaller fold, stands the high, isolated peak of Heart Mountain. This mountain is capped by Madison limestone, which rises as a huge block 500 to 600 feet above the slopes of the softer Cretaceous and Tertiary formations. The limestones dip to the northeast at an angle of about 15°. The highly colored shales of the Wasatch formation surround the base of the limestone cliffs alnd lie unconform- ably upon the steeply dipping beds of the underlying Cretaceous deposits. The dip of the Wasatch beds here is somewhat obscure, but they appear to lie horizontal or possibly to be slightly inclined to the east. North and east of Heart Mountain the Wasatch beds lie against the base of the limestone cliffs. About 2 miles northwest of the peak the relation of the Wasatch shales to the underlying Cretaceous beds is v/ell exposed. Here the latter dips at an angle of 45° to 60°, and across the upturned ends of these beds lie Wasatch shales, which dip eastward at a low angle. On the western side of Heart Mountain the dip and strike of the Cretaceous beds are unchanged from Pat O'Harra Creek to Shoshone River. The underground struc- tural relations of Heart Mountain are somewhat obscure, but the uplift is probably due to a circular fault, which raised the Madison limestone several thousand feet above its original position. Between Heart and Rattlesnake mountains minor flexures appear, the largest exposing a small area of the Sundance formation along the western side of Cottonwood Creek. South of Shoshone Ri^ver and east of Sage 38 GEOLOGY AND WATER RESOURCES OF BIGHORN BASIN. Creek there is a broad anticline extending southward, in which the lowest formation exposed is the Colorado. Structure of tTie Shoshone Mountains. — The Shoshone Mountains comprise the rugged mountainous district lying to the west of the Bighorn basin and extending from Shoshone River southward to Wind River. Carter Mountain, a prominent ridge at the northern end of the range, forms a high divide between South Fork of Shoshone and Gray Bull rivers. Only the eastern part of the Shoshone Range is included in the area described. The Shoshone Mountains were formed by an uplift which raised a thick series of Paleozoic and Mesozoic formations high above the plains, followed by deep erosion of its crest, and later deposition of a thick mass of volcanic and associated sedimentary rocks, which still retain their horizontal position. The most elevated part of the range in this district is the southern end, where a lofty peak, Washakie Needles, reaches an altitude of 12,496 feet, rising about 1,000 feet above the adjoining area. Structure of Sheep Mountain. — Across the eastern part of the basin there are a number of minor flexures, of which the most prominent are those comprising the Sheep Mountain uplift. This uplift is composed mainly of two anticlinal ridges marked by Sheep Mountain along the western side in the southern part of the uplift and Little Sheep Mountain along the eastern side toward the northern end. These ridges trend N. 50° W. ; they are nearly parallel, and the distance between their axes is about 5 miles. Sheep Mountain extends from near the mouth of Shell Creek to Dry Creek. It is due to a narrow anticline uplifted about 600 to 700 feet, exposing the Madison limestone along the crest of the ridge and in the walls of Black Can- yon. Little Sheep Mountain begins near Shoshone River and contin,ues southward to beyond Bighorn River, where the flexure becomes less prominent. About 2 miles east of Crystal there is an anticline exposing Chugwater beds on both sides of Alkali Creek. In its southern extension this anticline apparently joins vSheep Mountain south of Bear Creek. Farther south, along this line of uplift, tnere are a number of small anticlines, two near Bonanza, which expose the Sundance formation in their crest, and one on the western side of No Wood Creek below Bigtrails, which coalesces with the main uplift at its southern end. At the southeast corner of the area there is a sharp anticline through which No Wood Creek has cut a narrow, steep- sided canyon, exposing Madison limestone in its crest. To the north, in a direct line with Little Sheep Mountain, the southern extension of the Pryor Mountain uplift occurs. The lowest beds exposed by this uplift within the area considered in this paper is the Chugwater formation. Farther out in the basin there are a few smaller folds, one east of Garland, which exposes the Pierre shale, and another east of Windsor. Northwest of Frannie there is a small anticline that exposes the sandstone of the upper Colorado formation. Structure of the west side of the hasin. — Extending southward from the Oregon basin there is a low, broad anticline, exposing an area of Colorado formation. Far- ther south this anticline coalesces with the southern extension of the Rattlesnake Mountain anticline. To the west there is a broad syncline, the western limb of which lies along Sage Creek Valley. To the north this sjoicline passes between the southern extension of the Rattlesnake uplift and a fault which, along its upthrow side, exposes STEUCTUEAL AND HISTOEIOAL GEOLOGY. 6'd a narrow ridge of sandstone belonging to the upper part of the Colorado formation. The position of this fault is shown on the geologic map. To the south, in the vicinity of Meeteetse, the region is one of greater structural complexity. A series of anticlines with corresponding synclines crosses the region with a south-southeast trend from Meeteetse to the base of the Shoshone Mountains. Beginning at the base of the Shoshone Range the first fold, which is small and unimportant in the present consideration, crosses Gray Bull River about 2 miles above the mouth of Rock Creek. This fold is exposed in the Colorado shale. To the east, along Gray Bull River for a distance of 6 to 8 miles, the surface is occupied by Pierre shale. The Laramie formation is first encountered below the Frank ranch, where a bold escarpment of sandstone faces the west. From here the Laramie, etc., extends eastward for about 3 miles in a synclinal trough, followed to the east by an eroded anticline exposing Pierre and Colorado beds. These flexures have a northern extension of 4 to 5 miles, and to the south continue to Gooseberry Creek. Still farther east, near the mouth of Rawhide Creek, there is a low syncline and anticline and to the south toward Gooseberry Creek a number of folds occur. Upper Buffalo basin, the most prominent of these, exposes a large area of Pierre in its central portions. Two small anticlines which expose Pierre shale cross Gooseberry Creek near Renner's ranch. From the eastern slope of the low anticline at the mouth of Rawhide Creek the beds extend eastward with a low, uniform dip, passing beneath the Wasatch beds toward the center of the Bighorn basin. South of Dickie's ranch there is an anticline which presents a deep topographic depression, locally known as the "Upper Grass Creek basin. ' ' The center of this fold is occupied by Pierre shale encircled by a high wall of the overlying formation. On the south side of Grass Creek the beds dip steeply to the center of a narrow syncline in Wasatch, which extends to the west. Structure of the TTiermopolis anticline. — This anticline extends from the middle of R. 93, T. 43, west-northwest to the divide between Owl and Cottonwood creeks. A small area of Embar limestone is exposed on the crest of the fold near Thermopolis, surrounded by several square miles of Chugwater red beds. To the northwest the beds dip rapidly downward, carrying the Sundance, Morrison, and Cloverly forma- tions beneath the surface a short distance beyond Owl Creek. HISTORICAL GEOLOGY. General statement. — The geologic history of the Bighorn basin, as recorded ia the various rocks outcropping around its outer portion, extends from Middle Cam- brian time to the present. All the more important changes in physical geography which took place in the adjoining Bighorn and Rocky Mountain province, from the earliest Cambrian submergence to near the close of Eocene times, are recorded in the rocks of this region. These rocks comprise sedimentary strata several thousand feet in thickness which were originally a part of a much larger area now bordering the Rocky Mountain Front Range. Near the close of the epoch of early Tertiary moun- tain development, which resulted in the elevation of the Rocky Mountain Range and the Bighorn, Prior, and Owl Creek mountains, the district now comprising the Big- horn basin became surrounded on all sides by high mountain barriers. The elevation 40 GEOLOGY AND WATER BESOUEOES OF BIGHORN BASIN. of these inclosing ranges probably was greater than it is at present, for subsequent erosion has removed from their summits the softer sedimentary rocks and some of the granitic nucleus. The sedimentary rocks of the Bighorn basin consist mainly of sandstone, lime- stone, shale, sand, and gravel, all more or less variable in composition and appearance. The principal materials of which the sedimentary rocks are composed were originally sand, gravel, or calcareous mud derived from the decomposition of older rocks, or chemical precipitates from sea waters. Cambrian times. — The lowest sediments of this period are of middle Cambrian age. They are such as characterize shore deposits along a land surface of crystalline rocks. Numerous exposures occur in which sediments containing much local material can now be seen abutting against the crystalline, rocks that formed these shores. During the early part of this period the Bighorn Mountains were probably an island and the Rocky Mountain Front Range a highland rising out of the Cam- brian sea. After the earliest shore-line conditions a submergence followed and finer deposits of mud were laid down, which are now represented by shales and limestones in the upper part of the Cambrian. The limestone conglomerates of the Deadwood formation indicate shallow- water conditions, and the sandstone overlying the forma- tion probably marks the beginnmg of emergence which progressed through the early portion of Ordovician time. Ordovician period. — Later in the early part of Qrdovician time there was a sub- mergence of this entire region, and extensive deposition of lime carbonate which at first was mixed with a large amount of silica. The shores of this Ordovician sea were probably distant, some of them being in the Laramie Range to the south. Silurian-Devonian times. — Throughout the eastern portion of the district there is no geologic record from the close of Ordovician to early Carboniferous times, but to the northwest, in the Absaroka Mountains, deposits occur which are believed to represent these periods. The absence of Silurian and Devonian sediments in the Bighorn Mountains and adjoining region is difficult to account for. It may have been due to an extensive but shallow sea or land so low as to leave no noticeable evidence of erosion. Carhoniferous conditions. — During the subsidence which took place in early Carboniferous times, resulting in the establishment of relatively deep water and marine conditions throughout the Rocky Mountain province, calcareous sediments were laid down which are now represented by 600 to 1,000 feet of limestone, known as the Madison limestone. This formation contains no coarse sediments, a fact that suggests that possibly there were no crystalline land surfaces exposed in this region during its deposition. In regions to the south, however, limestones believed by some to be the stratigraphic equivalent of the Madison were deposited on crystal- line rocks. Following the deposition of these limestones there was a change in conditions, during which beds of red shale of wide extept, followed by cherty lime- stone, pure limestones, and, in some places, beds of sand, were deposited, which now represent the Amsden formation. Toward the close of Carboniferous times there was an uplift, and a period of shallow water with strong currents ensued, during which time there were deposited several hundred feet of sandstone, which now constitute the Tensleep formation. At the close of this period marine conditions HISTORICAL GEOLOGY. 41 prevailed and limestones were deposited, followed by the deposition, in a widespread saline lake, of 700 to 800 feet of red shale containing gj^psum, which now constitute the Chugwater red beds. These thick red shales and associated beds of gypsum were probably the product of an arid climate. The red color is not due to surface oxidation, but extends through the entire thickness, as has often been shown by deep borings, and is therefore the original color of the sediments. During the deposition of these red muds there were doubtless periods when, owing to evapora- tion, the waters became highly concentrated, and moife or less gypsum was precipi- tated throughout the sediments, which later segregated into massive beds of gypsum as we now find them. Most of the red deposits were laid down in shallow water, so that subsidence must have kept pace with deposition while they were accumu- lating. During the early part of the red-beds deposition there was an interruption which was widespread in the shale sedimentation, and a succession of relatively pure, thin-bedded limestones were laid down. In some locations outside of this area the supposed equivalents of these limestones are of Permian age, but further than this there is no satisfactory evidence as to the age of the red shales. They probably represent not only Permian, but a part of Triassic, times. Between the red shales of the Chugwater formation and the overlying Sundance there is in this region no suggestion of an unconformity, but in most localities there is evidence of uplift and erosion of the red beds in an interval prior to the deposition of the Sundance formation. Jurassic sea. — Throughout the Jurassic period shallow and deep marine waters alternated. The sediments are mainly fine grained, such as characterize waters without strong currents. Three principal events are recorded in the rocks of the formation — first, a period of shallow waters, during which sandy shales, in part ripple marked were laid down, followed by deeper water conditions, resulting in the deposition of limestones bearing an extensive marine fauna, with a return to shallow waters near the close, now indicated by sandy sediments. Cretaceous period. — In the Cretaceous period deposits that vary greatly in character, but that are generally of uniform type over wide areas, accumulated. The deposits at first were such as are characteristic of shallow seas and estuaries that lie along a coastal plain, passing into sediments derived from marine waters, and toward the close changing to fresh-water materials, mainly sand and clay with marsh vegetation. The earliest Cretaceous deposits constitute the Morrison forma- tion. This is a widespread deposit of material which is generally fine grained, con- sisting of clay and sand, with local beds of coarse sand deposited by streams. Dur- ing this period large saurians were more or less abundant, as is indicated by the remains now found in the sandstones. The fine-grained sediments of the Morrison are succeeded by coarse, pebbly sandstones of the lower part of the Cloverly forma- tion. Overlying the pebbly sandstones there are highly-colored, often sandy, clays, which are overlain in turn by a medium-grained sandstone, supposed to be the equivalent of the Dakota sandstone. Succeeding this period of fresh-water deposits there was submergence, and marine conditions were again established, as is indicated by the change of the sediments to dark-colored fissile shale. This marine sedimen- tation continued until there had been deposited several thousand feet of shale, which 42 GEOLOGt AND WATER RESOURCES OF BIGHORN BASIN. now represent the Colorado and Pierre formations. During this period there were several interruptions in shale sedimentation, which resulted in the deposition of sandstone and sandy shale. The most noteworthy of these was that in which the Mowry beds were laid down. During the period of Pierre deposition, which was of long duration, very uniform conditions prevailed, and there was apparently no break in shale sedimentation. The succeeding epoch marks the retreat of the Cretaceous sea. During this time there were extensive bodies of brackish water, which deposited sands, followed by fresh waters, in which were laid down several thousand feet of clay, sand, and marsh materials of the Laramie and associated formations. Early Tertiary deposits. — During early Tertiary times there was extensive uplift throughout the Rocky Mountain province. This fact is indicated in the adjoining mountain districts, where late Tertiary deposits lie upon an eroded surface which has the general form of the present topography. These relations show that the uplift was truncated and the larger topographic features formed in early Eocene times. During the erosion of these uplifts there began in the Bighorn basin the accumulation of the thick sediments which now constitute the Wasatch formation. These were laid down b}^ streams which, during most of the time, were sluggish and had extensive areas of overflow into bayous and lakes. B}^ this means the basin was covered and partly filled with materials derived chiefly from the early Mesozoic sediments, which then extended higher on the slopes of the inclosing ranges. This derivation is shown by the character of the clays now comprising the Wasatch formr.tion. After a long period, during which there accumulated 2,000 to 3,000 feet of Wasatch sediments and possibly a considerable thickness of later Tertiary deposits, a new cycle of erosion began, caused either by uplift or by the development of a lower' outlet for the drainage of the basin. Then began the erosion of the Tertiary deposits, but there was probably much shifting of drainage before the present system was developed. WATER RESOURCES. GROUND WATERS. All of the larger streams in the Bighorn basin carry an abundance of good water, and in consequence few wells are needed, the water for domestic purposes being sup- plied by the streams directly or through the larger irrigation canals. In the vicinity of Germania a number of shallow wells obtain water from the later terrace gravels, but its quality is poor. At Garland a relatively deep surface well sunk in the Laramie formation obtained water which is highly mineralized, and there are a number of springs throughout the district which have small flows of alkali water derived from the gravel terraces. Along Gray Bull River there are a few shallow wells that obtain water from the valley deposits, but many of the ranchers use river water. In the Bighorn River Valley the water of shallow wells is generally mineralized, and for this reason much of the domestic water supply comes from the river. The same conditions exist in the valleys of No Wood Creek and its principal tributaries. Along Owl Creek a number of shallow wells furnish water that contains more or less "alkali.'' WATER RESOURCES. 43 UNDERGROUND WATERS. A number of the formations exhibited in the Bighorn basin consist largely of porous rocks, mainly sandstone. These rocks undoubtedly contain water in their underground beds. They outcrop around the outer portion of the basin and extend far up the slopes of the ridges, where in many places they imbibe water from rain and from streams fed by melting snows on the summits of the mountains. In their under- ground beds they lie immediately beneath impervious shales. To this extent the con- ditions for underground water are favorable, but the dips are generally steep, and the water-bearing formations are carried rapidly to depths too great to be reached by practicable well borings. Along the eastern side of the basin, between the Sheep and Bighorn Mountain uplifts, there is a small area where the conditions are favorable for artesian water. The structure of the formation in this region is shown in the cross sections on PI. IV, p. 8. In several places along the eastern side of the basin there are long monoclinal slopes of Tensleep sandstone traversed by numerous mountain streams. These slopes afford excellent catchment areas for artesian water, and at their base, in the low valleys, the conditions for artesian water are very favorable. The most promising localities are the lowlands bordering Bighorn River on the west, in the region north of Ionia, in all the larger red-beds valleys along the base of the mountains between Shell and Tensleep creeks, and in the upper parts of the valleys of Alkali, Spring, Otter, and Little Canyon creeks. ■Along Owl Creek Valley, in the vicinity of Embar, and near the mouth of Mud Creek, artesian water might possibly be obtained froiii the Cloverly formations at moderate depth. The water-bearing formations of the basin are the Cloverly, Tensleep, and Amsden. Of these the Tensleep and Cloverly formations are perhaps the most important. The latter consists largely of sandstone, like the water-bearing sandstone beneath the central Great Plains. Though no . practical tests have been made of the water capacities of the Cloverly sandstones in this fegion it is probable that they contain considerable water. They lie at a depth of several thousand feet from the surface under a great part of the basin, but in the region east of the Sheep Mountain uplift, between Shell Creek and Shoshone River, they can be reached by well borings less than 1,200 feet deep. Flows could be obtained, however, only in the valleys of the streams, and as most of these streams carry an abundance of fine water artesian wells are not required. The Laramie and associated formations are water bearing, but owing to their steep dips, especially in the northern portion of the Bighorn basin, it has not been practicable to sink artesian wells into them. In Gray Bull Valley, in the vicinity of Meeteetse, however, several small flows have been obtained from the sandy members of these formations. The Tensleep and Amsden formations in the basin are very promising artesian-water horizons, but they are generally too deeply buried by overlying sediments to be reached by well borings. Artesian water could probably be obtained in the valley of Sage Creek, between Frannie and Shoshone River, at depths not exceeding 2,000 feet. The first water- bearing bed which would be encountered in this region in sinking a deep well is a sand- stone in the upper part of the Colorado formation. At Cowley this sandstone was penetrated at a depth of about 500 feet. The next water-bearing horizon below the 11774— No. 53—06 i 44 GEOLOGY AND "WATER RESOURCES OF BIGHORN BASIN". sandstone of the Colorado formation is the Cloverly formation, which is about 1,200 feet deeper, or approximately 1,700 feet from the surface at Cowley. Northwest of Frannie, outside the region to which this paper relates, artesian flows were obtained at a depth of 1,000 feet by the Montana and Wyoming Oil Company in borings made for oil. In the valley of Gypsum Creek there is a small area where artesian water could probably be obtained at less than 400 feet. IRRIGATION. General statement. — Irrigation has been practiced in the Bighorn basin for about twenty 3^ears, but its growth and development have been necessarily slow until recently. The region is far from good markets, and for the first few years irrigators were compelled to depend entirel}'^ upon the local demand for the disposal of their pfoduce. This demand has sometimes been inadequate, and farmers were obhged to hold their grain from one season to another or give it in exchange for other commodities. These conditions have retarded development in some of the irrigated districts. Settlement was first made along the eastern side of the basin, and here, in the valleys of the larger mountain streams, some of the earliest irri- gation ditches were constructed. The lowlands bordering the streams were first farmed, but as the population increased higher portions of the valleys were brought under cultivation, and at present a large percentage of the irrigable lands is utilized (PI. XII) . Extensive preparations are also being made, both by the Government and by private enterprise, to reclaim large tracts of land along Bighorn and Shoshone rivers and Dry Creek in the central portion of the basin (see p. 46). Bighorn River. — Along the Bighorn River Valley in the northern part of the basin irrigation is not extensively practiced. The low bottom lands are generally very sandy, and the gravel terraces bordering the river are too high to be watered by short ditches. Small marginal areas are irrigated along the western side of Bighorn River, mainly below the mouth of Gray Bull River, in the vicinity of Crystal; along Alkali Creek, a small tributary of Bighorn River from the east, and in the vicinity of Kane. None of these areas are large. The water is usually conveyed by small ditches, each ranch having a separate canal. Crooked Creek, a tributary of Bighorn River from the west, supplies water for a narrow area of valley land along both sides of the stream from its mouth to the base of Pryor Mountain. Above Basin on Bighorn River several irrigated districts occur, and at present two large canals, the Hanover canal and Bighorn County canal, are being constructed on either side of the river, which will reclaim approximately 48,000 acres of land between Winchester and the mouth of Gra^^ Bull River. Shoshone River. — At present, irrigation along Shoshone River is practiced mainly in two districts; one lying on the southern side of the river between Cody and Corbett's bridge (PI. XIII, A), the other, a larger area, extending eastward from Garland bridge to Bighorn River. On the northern side of Shoshone River the Cin- cinnati canal covers a large area. It is about 25 miles long, and furnishes water for the region around Byron and Cowley, the total area irrigated comprising approxi- mately 23,000 acres. South of Shoshone River is the Lovell Irrigation Company's canal, which extends from a point south of Garland to Bighorn River. This is a L.L.POATES, ENGB'SCO. , ft. IRRIGATION. 45 high-line canal, and when completed will furnish water for all the higher irrigable land on the southern side of Shoshone River. A number of small ditches supply water to the lower portion of the valley between Lovell and Ionia. The valley lands are very fertile, especially in the vicinity of Lovell, and a variety of crops are cultivated. Alfalfa is the staple, but during the last three years much grain has been produced. Cultivation of sugar beets has been attempted and has generally been successfid. Clark Fork. — Along Clark Fork and its various tributaries much land is irri- gated, as shown in PI. XII. Throughout the upper portion of Clark Fork Valley the alluvium is composed largely of coarse gravel and bowlders, containing only a small proportion of sand and silt, and in consequence is not well adapted to culti- vation. The valley of Pat O'Harra Creek, the principal tributary of Clark Fork, is very narrow, but is exceptionally fertile. Along Paint, Newmeyer, and Little Rocky creeks and the upper courses of Bennett and Line creeks there are a few small irrigated farms. Gray Bull River. — Irrigation is extensively practiced along the entire course of Gray Bull River, but the amount of water in the stream is not adequate for the irrigation of all the valley lands without storage of its flood waters. A preliminary survey was made in 1899 for the purpose of locating a storage reservoir on the head- waters of the Gray Bull, and, as a result of this investigation, a dam and reservoir site was located on the river about 10 miles above Fourbear. The approximate boundaries of the irrigable lands are shown in PI. XII. The soil is very fertile, and a large amount of hay and grain is raised in the vicinity of Meeteetse, where irrigation has been practiced for many years (see PI. I, B). Shell Greek. — The waters of Shell Creek and its tributaries have been used for irrigation for nearly twenty years. The stream has a large flow of water, and its fall is about 25 feet to the mile. It is bordered by a relatively wide valley, which has gentle slopes, affording ideal conditions for irrigation. The soil is generally deep and fertile and well adapted to the cultivation of a variety of crops. A number of small ditches have been taken out on both sides of the stream, and a large part of the land is farmed. Alfalfa is the principal crop, but grain also is raised. There are a number of bearing orchards along Horse Creek, the largest tributary of Shell Creek from the north. The seasons are of sufficient length in this region to insure the maturity of most crops. Other flowing streams. — A portion of the land is irrigated along the valleys of Gooseberry, Grass, and Owl creeks.- The latter has a wide, fertile valley, only a part of which is irrigated, owing to a shortage of water. Owl Creek has a vigorous flow for a short period during the flood season, but this flow rapidly decreases, and in midsummer the stream below Embar is nearly dry. On No Wood Creek and its principal tributaries, Paintrock and Tensleep, the valley land is extensively irrigated. The soil along these streams, although pre- dominately sandy, is very fertile, and a variety of crops are cultivated. Small storage reservoirs have been located on Dry Cottonwood and the East Fork of No Water creeks, and the land to be irrigated from these reservoirs is shown in PI. XIL 46 GEOLOGY AND WATER EESOUEOES OF BIGHORN BASIN. Dry Greek. — Around Germania there is an irrigated district comprising about 12,000 acres, which receives its water supply from the Branch canal. This canal is diverted from Gray Bull River in the vicinity of Fenton. A large acreage of oats, wheat, and alfalfa is here under cultivation; also a variety of vegetables. As Dry Creek is an intermittent stream the community is dependent upon the ditch water for domestic uses as well as for irrigation. The Bighorn Basin Development Company is now making preparations to reclaim all the irrigable lands' along Dry Creek from Oregon basin to Bighorn River. The water is to be taken from South Fork of Shoshone River near the mouth of Belknap Creek and carried through a high-line canal for nearly 30 miles to Oregon basin, where it is to be stored. From here it will be distributed by two large canals — the Shoshone and the South Fork. The lands to be reclaimed by this company are shown in PI. XII. Irma Flats. — Southwest of Cody, Wyo., is a small farming district comprising about 2,000 acres, known as the Irma Flats. This district is supplied with water by the Cody canal, which has its headgate on South Fork of Shoshone River near the mouth of Marquette Creek. Shoshone project. — The Government is now constructing a dam across Shoshone River at the upper end of Shoshone Canyon for the purpose of storing a portion of the flood waters of that river. The dam is to be 85 feet wide in the river bed and 165 feet wide at an elevation of 210 feet. A dam of this size will have a storage capacity of 159,500 acre-feet. The water from the storage reservoir is to be used for irrigating along the northern side of Shoshone River in a district extending from the mouth of Shoshone Canyon to beyond Frannie station, a distance of about 60 miles, and comprising an area of about 282,000 acres of level land. (See' PI. X, A.) The distribution of the land to be irrigated is shown in PI. XII, and the dam site (PI. II, B) and storage-reservoir site in PI. XIII, B. MIIS^ERAL RESOURCES. GENEEAL DESCRIPTION. Coal is the principal mineral resource in the sedimentary formations of the Bighorn basin. It occurs mainly in the so-called Laramie formation, although on the western side of the district a coal, said to be of good quality, is found in the upper part of the Benton group, and on No Wood Creek, 12 miles southeast of Bonanza, a local deposit of coal is mined from the Cloverly formation. The coal is found at various horizons throughout the Laramie and associated formations, but most of the deposits of workable thickness are in a basal member of this formation or possibly in beds still lower. Coal'is widespread in its distribution within the area occupied by the Laramie and associated formations. The greatest development, however, is found in places where the larger streams expose the coal measures. Here the most favorable conditions exist for locating mines and the increased settle- ment of the irrigated valleys along the streams afford local market for the coal. The various districts in the Bighorn basin, where the principal development of the MINERAL RESOURCES COAL. 47 coal deposits has taken place, are described separately. The limits of these districts are arbitrarily taken and they are designated by the nearest town. CODY DISTRICT. Coal is mined at several localities in the vicinity of Cody. The Navine mine, 3J miles northeast of Cody, on the opposite side of Shoshone River, is the oldest mine in the district. Coal has been taken out of this opening for several years to supply a small ranch trade along the valley. The deposit is between 2 and 3 feet thick. During the last three years the increase in population in the vicinity of Cody has caused a greater demand for fuel, and in consequence several new mines have been opened. These are the Burns & Rogers mine, the mine of the Cody Coal Company, and others. The Burns & Rogers mine is situated 5 miles south- southeast of Cody, on the west rim of a small syncline through which Sage Creek flows. The coal here is in the lower portion of the coal-bearing measures. The deposit consists of three benches separated by two slate partings. It has an east- ward dip of 47° and is included in beds of massive gray sandstone. An inchne 90 feet deep has been driven on the seam, with a large room on either side. The coal is hard and black, with a bright luster and uneven fracture. It does not break up badly on exposure to atmospheric agencies and as a domestic coal is said to be very satisfactory. The product of this mine will probably never be large, for the deposit is thin and the dip of the beds is so steep that the limit of economic working will soon be reached. This coal finds a market in Cody and in the Shoshone River Valley. The following section was measured at the Burns & Rogers mine : Section at the Bums & Rogers mine, near Cody, Wyo. Ft. in. Coal : 10 Impure coal 6 Coal 1 2 Gray slate 3 Coal 1 During the past season the Cody Coal Company has opened a mine on the northern side of Shoshone River about 3 miles east of Cody station. The coal occurs about 1,500 feet above the top of the Pierre shale in beds dipping at an angle of 45° to the east. The deposit is about 4^ feet thick and is apparently of good quality, although no analysis of the product was available. The opening of this bed is in the face of the bluffs about 30 feet above the railroad, so that the coal can be loaded for shipment at small expense when the new side track now being built is completed. The mine is well timbered and preparations are being made for more extensive development. A section of the deposit is as follows : Section of Cody Coal Company's mine, Cody, Wyo. Feet. Dark sandy clay , .----• - 6 Coal 4 Coaly shale 2 Dark sandy clay 8 Gray massive sandstone , 20 48 GEOLOaT AND WATER EE80UECES OF BIGHORN BASIN. Arrangements are now being made by another company to develop coal beds at the same horizon on the southern side of Shoshone River. Some prospecting has been done on Sage Creek and its tributaries in the vicinity of Frost's ranch. Other prospects occur in the high bluffs of Wiley's ranch and on Dry Creek east of Oregon basin. None of these openings are worked at present. Some development work has been done on a bed of coaly shale on the eastern side of Sage Creek about 2 miles above its mouth. The coal occurring in the Colorado formation just west of Cody bridge was formerly mined to some extent. MEETEETSE DISTRICT. In the vicinity of Meeteetse there are a number of coal mines which have been operated more or less extensively for the last fifteen years. The region is one of considerable structural complexity, with a number of low anticlines and intervening synclines crossing it. This folding has greatly increased the surface area of the coal-bearing formations, bringing the productive beds near the surface over a con- siderable area. The Conie mine, on the Meeteetse rim, 12 miles northwest of Meeteetse, was reopened in 1903 after lying idle for several years. The coal is in relatively thin beds, lying nearly horizontal. It is black with an unusually bright luster, brown streak, and subconchoidal fracture. The woody structure is maintained to a marked degree, and its resistance to weathering is slight. Its occurrence in a soft-clay formation renders it difficult to mine and the absence of a solid roof necessitates elaborate tim- bering, greatly increasing the cost of operation. The mine is located in an inacces- sible place and will probably never be extensively developed. The character of this coal bed is illustrated in the following section: Section at Conie mine, near Meeteetse, Wyo. Ft. in. Coal 1 2 Bony coal 7 Coal n Dark-grav slate _ 4 Coal....!.. 1 6 Dark-gra}^ slate 1 8 Coal - 1 6 Slate 4 Coal 8 The Orr mine is situated on a branch of Meeteetse Creek, about 3 miles north- west of Wise. It is well opened with a double well-timbered entry, extending 100 feet from the outcrop. The bed consists of two benches, each 3 feet thick, separated by a layer of light-bluish-gray slate which is characteristic of this horizon. The coal is black with a bright luster, brown streak, and uneven fracture. This mine is worked during the winter months with a seasonal output of 300 to 400 tons. Con- siderable prospecting has been done near the Orr mine and one opening has been made about a mile south which exposes a 6-foot bed of coal. The Blake mine is located about 3 miles above Meeteetse, on the north bank of Gray Bull River. Here a seam 5 feet 9 inches thick has been extensively operated, MIKERAL RESOUECES — COAL. 49 and is one of the oldest openings in the district. The dip of the beds is 9° NE. The main entry is about 150 feet in length, with several side entries. The workings are too low in the river bank for perfect drainage to be effected, and some little difficulty has resulted from this condition. Operations were first begun at this place in 1892, but there was only a small output until 1898, when the property was purchased by the present owners. The total production from 1898 to 1902 exceeded 2,000 tons. In 1902 the product amounted to 900 tons with a market value of $2 per ton at the mine. At present the mine is not worked. There is another opening on the same horizon a short distance up the river which was formerly owned by McDonald & Cottle, of Thermopolis. The dip in this region is low and the conditions are generally favorable for more extensive development of these properties. Section at the Blake mine, near Meeteetse, Wyo. Ft. in. Bony coal ' 6 Clay and sandstone 6 Coal , 3 3 Bluish-gray slate - . . 3 Coal.... V--- 2 6 Impure coal 6 During the summer of 1904 an opening was made on a bed of coal in the upper part of the coal-bearing formations near the mouth of Meeteetse Creek, about 2 miles north of Meeteetse,- Wyo. It is now known as the Woodruff mine. The seam is 4 feet thick with no partings. It is overlain by hard, gray sandstone and under- lain by a dark-colored compact clay. An entry 150 feet deep has been driven in the seam, with several large rooms on either side. The coal is hard and black with a bright luster. It appears not to break up badly upon exposure, and as a domestic coal is said to be very satisfactory. No analysis has been made of this coal. During the past two years the Woodruff mine has had a total output of 2,200 tons, which sells at $2.25 per ton. The coal finds a ready market at Meeteetse, Wyo. Another mine recently opened near Meeteetse is owned by Mr. Erskin. It is located in sec. 13, T. 48, R. 101, about 2^ miles above Meeteetse, in the lowland of the Gray Bull Valley. This mine is on the same seam as the Edward Blake mine, which has been worked for many years on the northern side of Gray Bull River. The coal beds have a dip of 6° to the east and are somewhat thicker than on the opposite side of the valley. The output for last season, during the period of develop- ment of the mine, was about 400 tons. There is a bed of coal 3 to 4 feet in width, occurring in dark-gray sandy shales 400 feet below the base of the Wasatch, about 3 miles southeast of Meeteetse. This coal has been prospected at a few places along the stage road between Meeteetse and Moon's ranch, on Gooseberry Creek, but no mines have been opened. It is possible that a more extended search for coal at this horizon might result in the discovery of workable beds. That portion of the Meeteetse district lying south of Gray Bull River is sepa- rated into two parts by erosion along an anticlinal fold. The main body of coal- bearing measures lies east of Wood River, between Gray Bull River and Gooseberry 50 GEOLOGY AND WATER RESOURCES OF BIGHORN BASIN. Creek, and a detached portion occurs west of Wood River. There are several anticlinal folds in the main body which bring the lower coal-bearing measures of the Laramie to the surface in a number of places along Gooseberry Creek, but openings have been made in only two localities. In a small ravine entering Gooseberry Creek from the south, and on the eastern rim of a small anticline, there is a coal opening kno^wTi as the Dickie mine No. 1. This mine exposes a bed of bright, clean-looking coal 4J feet thick without parting. The coal is immediately overlain by a 2-foot layer of gray clay, fine grained and compact, containing carbonized plant fragments. The coal is in the lower part of the coal-bearing measures and dips at an angle of 17° ENE. The mine has never been worked extensively and the main entry extends but a few feet. The coal, however, is of good quality and the general conditions are favorable for development. There is another bed about 12 feet lower, the general character of which could not be ascertained owing to talus. The accompanying section shows the relative position of the two beds : Section at the Dickie mine No. 1, on Gooseberry Creek, Wyoming. Feet. Gray compact clay 2 Coal 4J Gray clay 3 Buff sandstone 6 Brown sandstone : 2 Impure coal 6 About 3 miles southeast of Dickie mine No. 1, and 1 mile north of Grass Creek, Mr. Dickie has opened a coal bed 8 feet 3 inches thick, which is locally known as Dickie mine No. 2. The coal occurs near the base of the coal-bearing measures, which here comprises the western rim of a large eroded anticline extending from the vicinity of Gooseberry Creek southeastward to Grass Creek and intersecting the latter at a point 3 miles above the mouth of Prospect Creek. The longitudinal axis of this anticline is 12 to 15 miles long and the transverse axis is considerably shorter. The central body of the basin is composed of Pierre shale, surrounded by coal-bearing sandstone. The only coal openings observed on this sandstone rim were the Dickie mine No. 2 and a small showing on the southern side of Grass Creek about a mile distant. Coal of this horizon is said to outcrop, however, at frequent intervals along the southern rim of the anticline for some distance. The coal seam in Dickie mine No. 2 consists of two benches, separated by the usual bluish-white shaly parting near the middle. A 2-inch layer of light-gray shale also occurs near the top of the upper bench, but neither of these partings is sufficiently thick to affect materially the productive capacity of the seam. The coals of the upper and lower benches exhibit no essential points of difference in quality. The product is rather hard and compact, with an unusually bright luster, and a chemical analysis shows it to be an average quality of lignite. The mine is not operated at present, but the quality of the material, com- bined with the size and character of the seam, render it a desirable property. A section of the bed is given below: >-^;>i 1>. MINERAL RESOUKOES COAL. 51 Section at DicMe mine, No. 2; near Grass Creelc, Wyoming. Ft. in. Coal 4 6 Light bluish-gray slate 3 Coal " - - 9 Light-gray slate 2 Coal 3 The small detached area of coal-bearing measures lying west of Wood River is structurally a synclinal trough comprising about 25 square miles and extending from a point 3 miles rwrth of Gray Bull River southeastward to Wood River. This area is about 10 miles long and 2 to 3 miles wide, and its axis trends N. 5° W. The forma- tion is the lower part of the coal-bearing measures. The sandstones of this formation in the region are heavily developed, and massive sandstone layers 20 to 30 feet thick occur immediately above and below the coal horizon, the upper having a white and the lower a yellowish tint. The color and thickness of these two sandstone layers are very persistent throughout the Meeteetse district, and serve as an indicator of the position of the coal. The dips vary from 20° to 40° from rim to center, with a direc- tion according to their position on the periphery of the syncline. They are very steep along the eastern and northern sides, but to the west and south they decrease materially. The area is encircled by a continuous coal outcrop . The lower coal bed of the basal sandy division probably underlies the entire district, and the upper seam, 75 feet higher, here locally attains a workable thickness. Development has been chiefly confined to Sunshine Gulch and its tributaries, about 3 miles north-northwest of Sunshine post-office, although openings have been made at other points within the area. None of these localities are operated at present, but the coal is said to be of good quality. The average thickness of the lower coal bed in Sunshine Gulch is 6 feet, while the upper seam is only 2 feet 8 inches. A coal bed averaging 3 feet in thickness contains about 3,000,000 tons of coal per square mile, but of course there is considerable loss in working. There are now in this field about 18 square miles underlain by coal that would doubtless average 4 or more feet in thickness. On this estimate the field has a productive capacity of 72,000,000 tons. A trial pit near the north end of this area, in the sandstone bluffs on the south side of Gray Bull River, exhibits the following section : Section at Vetter's coal opening, near Meeteetse, Wyo. Ft. in. Bony coal 3 Coal 10 Bony coal. 2 Coal 1 6 Light bluish-gray slate _ 3 Coal 1 Dull-gray slate _ 1 Coal 4 Bluis.h-gray clay 2 6 South of the Meeteetse district, in the vicinity of Embar, there is a small open- ing known as the Smith mine, which was formerly operated to some extent, but at present is abandoned. Some of the earlier analyses of this coal show a liigh fuel 52 GEOLOGY AND WATER RESOURCES OF BIGHORN BASIN. ratio, but an unusually large amount of moisture. There is another small mine, about 2i miles northeast of Middleton post-office, known as the Eades mine. The bed is 4 feet thick without parting, and occurs in the massive gray sandstone not far above the top of the Pierre shales. The beds dip 9° to the north. From an incline about 60 feet in length that has been driven on the dip a small amount of coal is taken out during the winter season. The coal in appearance is black, with a bright luster and uneven fracture. It does not weather easily. The following section was measured : Section at Eades mine, near Middleton, Wyo. Feet. Dark-gray compact clay 2 Impure coaly shale 1 Coal _ . 4 THERMOPOLIS DISTRICT. This district is located on the western side of Bighorn River, about 12 miles north-northeast of Thermopolis, and a few miles below the mouth of Kirby Creek. The formation consists of alternating layers of massive gray sandstone, sandy shale, and clays with a locally developed clinker bed occurring immediately below the principal coal seam of the district. This is the only clinker bed thus far observed in the Bighorn basin. The dip of the beds is 17° NNE. The Jones mine was opened in this district in the summer of 1889, but the output was small for the three following years, scarcely exceeding 200 tons a year. Since 1900 the annual output has increased to over 1,000 tons, but as yet only a small part of the field has been worked, and the present production of this locality could be increased many times. Operations have now ceased at the Jones mine, and a new opening has been made by McDonald & Cottle (PI. XIV, A). The principal bed is 9 feet thick, over- lain by a bed of sandy clay of variable thickness. Above this is another coal bed 5 feet thick. In the McDonald & Cottle mine the sandy clay reaches a minimum thickness of 2 inches, which practically unites the two seams, giving a total thickness of 14 feet (PI. XIV, B). This is the thickest coal seam thus far observed in the Bighorn basin. Five other closely adjacent beds occur, four below and one above the 14-foot bed; three of ihe lower beds are said to be workable. The uppermost, outcropping 25 feet below the McDonald & Cottle vein, is 3 feet thick and apparently of good quality. The total thickness of the various beds exposed within close ver- tical range is approximately 30 feet. The material is a bright, firm, free-burning variety of coal. It gives a brown streak, breaks in blocks, and does not crumble easily on exposure. An analysis shows a rather high per cent of fixed carbon and moisture and only a small amount of ash. At the McDonald & Cottle mine the following section was taken : Section at the McDonald c& Cottle mine, near Thermopolis, Wyo. Ft. in. Coal 5 Dark-gray sandy clay _ 2 Coal 9 GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 63 PL. : ig cDONALD & COTTLE MINE NEAR THERMOPOLIS, WYO. A. Entrance. B. Coal bed. MINERAL RESOUECES COAL. 53 An area of 1 square mile underlain by a coal bed 14 feet thick would contain 14,000,000 tons of coal, an amount far exceeding the total product of the Red Lodge mines during the past fourteen years. Of course, there is always a loss in working, and in an area of broadly lenticular coal deposits allowance must be made for a cer- tain amount of variation in thickness. In an area underlain by 30 feet of coal, 1 square mile would contain 30,000,000 tons, or supposing that on an average only one-half that thickness were found, there would be 15,000,000 tons of coal. A deter- mination of the productive capacity of the entire Thermopolis district was not undertaken in the present reconnaissance. The total coal acreage of this region can be only rudely estimated, for no systematic prospecting has ever been conducted, but coal outcrops may be seen along the strike of the beds for several miles, and as the dip is uniform and moderately low the field is undoubtedly large. NO WOOD DISTRICT. An opening has been made in a coal bed which outcrops near the base of a promi- nent hill at the Fiead of Bud Kimball Draw, 14 miles southwest of Tensleep, Wyo. Coal is not mined here regularly, but many of the settlers along the No Wood Creek Valley obtain their fuel supply from this place. The coal bed, which occurs in the lower part of the Laramie and associated formations, has an aggregate thickness of about 6^ feet, consisting of four benches separated by a parting of bony coal and brown leaf -bearing shale. Section of coal-hearing heds near head of Bud Kimball Draw, Wyoming. Ft. in. Brown leaf-bearing shale Very impure coal 10 Gray sandstone 4 Coal containing thin layers of bone 3 6 Brown leaf-bearing shale 10 Bony coal . . 3 Coal 9 Bony coal 4 Coal 1 6 Bony coal _ 6 Coal 1 Total 9 10 About 3 miles southeast of Bell's ranch, on No Wood Creek, there is a small coal district. The principal interest attached to this locality is the fact that the deposits are contained in the basal sandstones of the Cloverly formation, less than 50 feet above the Morrison formation. The coal has been prospected at frequent intervals for 2 or 3 miles along the strike, which here trends east-southeast, but at present operations are confined to one opening, known as the Diehl & Bell mine. The deposit consists of two benches each 4 feet thick, separated by a 2-inch layer of dark-colored shale. In appearance the coal is dark, with dull, earthy luster, conchoidal fracture, and resembles closely a carbonaceous shale. The accompanying section will show the thickness and relative position of the coal seams. '54 GEOLOGY AND WATER RESOURCES OF BIGHORN BASIN, Section at Diehl <& Bell mine, near Tensleep, Wyo. Ft. in. Coal 4 Dark-gray slate 2 Coal 4 BASIN DISTRICT. The next locality of coal outcrops to the northwest is locally known as the Basin district, because of its nearness to Basin, the county seat of Bighorn County. There are two small mines in this district; the larger one, located near the mouth of No Wood Creek, about 5 miles southeast of Basin, is owned by Rogers & Gapen. It has been worked continuously for about five years, although coal has been taken from this opening for more than a decade. The deposit has a measured thickness of 5 feet and contains many thin, slaty partings, which, although numerous, are in total thickness insufficient to render the deposit unfit for economic development. Since 1900 the product has averaged about 400 tons a year, with a market value of $2 per ton at the mine. The character of the seam is illustrated in the following section : Section at the Rogers & Gapen mine, near Basin, Wyo. Ft. in. Coal 1 1 Impure coaly shale. I Coal 8 Black shale 2 Coal 7 Dark-gray clay 6 Coal 5 Coaly shale 2 Coal 11 Dark-gray clay 2 Coal 1 3 There is another mine in this district, located about 1 mile southwest of Basin, owned by G. N. Mecklen. The bed is 2 J feet thick, with a 6-inch shaly parting near the base. The coal is contained in sandy beds, which here dip to the south at such a steep angle that the limit of economic mining will soon be reached. This mine produces about 600 tons a year, which is consumed by the residents of Basin and the Bighorn River Valley. The mine is poorly improved and the bed is too thin to warrant any considerable development, as is shown by the following section: Section of Mecklen mine, near Basin, Wyo. Ft. in. Coal --- I - 2 Dark-gray slate 6 Coal - - . 6 Along the exposed area of the coal-bearing formation, between Gray Bull and Shoshone rivers, some prospecting has been done, resulting in the location of a few thin coal deposits, all of which are under the limit of a profitable working thickness. MINEEAL BESOURgES COAL. 55 GARLAND DISTRICT. About 3 miles northwest of Garland there is a small coal-mining district. The coal occurs in sandstones comprising the lower portion of the coal-bearing measures. The productive beds outcrop in low sandstone ridges that dip gently southwestward and soon pass under higher beds toward the center of the basin. Two mines are worked at present, one by the Wyoming Coal and Fuel Company and the other by the Garland Coal Company. They are located within a few yards of each other and both are working on the same coal horizon, though a comparison of the deposits at the two openings shows considerable variation. At the former the seam is composed of an upper and a lower bench containing two distinct varieties of coal. In the upper bench, which is 2 feet 2 inches thick, the coal is black, with a bright luster. It occurs in layers and breaks into blocks. The lower bench, which is 1 foot 4 inches thick, consists chiefly of a brown, coaly shale with numerous thin layers of coal. The proportion of shale to coal varies, the former sometimes disappearing entirely. The two benches are not separated by a layer of slate, as is usually the case at this horizon, but the sudden change in the character of the material indicates the dividing line. At the Garland Company's mine a slightly different section is observed. Here there is an increase in the thickness of the upper bench, but in quality there appeared to be no essential points of difference. In the lower bench the coal predominates over the coaly shale. The change is due to the rapid thickening and uniting ol the thin coal la3'-ers. The product of both benches resists weathering fairly well for a lignite. Midway between the two mines the Wyoming Coal and Fuel Company has opened at this horizon a trial pit, which exhibits 4 feet 3 inches of coal without parting. The coal of the lower, bench is entirely free from shale, and in its physical properties appears superior to that of the upper bench. The beds in this region have uniformly low dips and the coal could be easily mined. The mines are less than 1 mile from the Mantua switch on the Toluca-Cody branch of the Burlington and Missouri River Railroad, so that a side track might be constructed at small cost, which would enable the companies to ship their coal. The following measurements were made at the three different openings along the strike : Section at the Wyoming Coal and Fuel Company's mine, Garland, Wyo. Ft. in. Coal __.. 2 2 Brown carbonaceous shale with streak of coal _ . . 1 4 Section at the Garland Coal Company's mine. Garland, Wyo. Ft. in. Dark-gray clay 2 Coal ^ 3 6 Coal with streaks of carbonaceous shale 2 6 Section at coal prospect, made hy Wyoming Coal and Fuel Company, Garland, Wyo. Ft. in. Dark-gray compact clay. 4 Coal 4 3 56 GEOLOGY AND WATER EESOURCES OF BIGHORN BASIN. SILVER TIP DISTRICT. This is a small district located on Cottonwood Creek on the north side of the divide between Clark Fork and Shoshone River. The deposit has been prospected at several places in the immediate vicinity, but the principal opening, the Silver Tip mine, is in sec. 29, T. 58, R. 100. Here considerable coal has been taken out for the last three years, chiefly to supply the ranch trade of Clark Fork Valley. The total thickness of the bed is 5 feet, including two partings of impure coal and a thin layer of soft light-colored clay. The main entry is driven in about 125 feet from the outcrop, and throughout this distance the character of the coal bed fixed appears to be uniform, and analysis of this coal shows a moderate amount of carbon and volatile matter with relatively low percentages of water and ash. A sectiop. of the coal bed at the Silver Tip mine is here given: Section at Silver Tip mine on Cottonwood Creelc, Wyoming. Feet. Gray compact sandy clay 4 Brown leaf-bearing shale 3 Coal 5 Gray sandstone ^ 6 Impure coal with streaks of leaf-bearing shale. 2 Dark-colored sandstone 5 BENTONITE. The variety of clay known as bentonite was first described in 1898, by the late Prof. W. C. Knight, of the Wyoming State School of Mines, and since that time several articles have appeared in scientific journals, a list of which are given below. " The mineral is a hydrous silicate of alumina, possessing peculiar physical properties. It occurs at various horizons in the Colorado formation and in the overlying Pierre shale. ■ Fresh bentonite has a pale yellowish-green color, but on exposure it changes to a light-cream tint. It is a fine-textured, soft, massive variety of clay, which is unctuous to the touch and which, upon the addition of water, forms an emulsion. It is characterized by its • unusual power of absorption, having the capacity of absorbing three times its weight of water. In a comparative test it is reported to have taken twice as much nitroglycerine as infusorial earth. When first taken from the quarry, it breaks with conchoidal fracture, but upon exposure loses this property and crumbles to a light yellowish powder resembling corn meal. The specific gravity of this clay, when fresh, is 2.18. Its resemblance to ehrenbergite of Germany has been pointed out by Mr. Knight and its relationship to montmo- rillonite by Mr. Read. The clay from different localities varies somewhat in compo- sition, but in general it is quite uniform in a single deposit. This clay has been used with success in various ways, chiefly in the manufacture of paper. It has also been used as a soap. It is regarded valuable as a packing for a special kind of horseshoe and as a diluent for certain powerful drugs in powdered a Knight, W. C, Eng. and Min. Jour., vol. 63, 1897, pp. 600-601; Knight, W. C, Eng. and Min. Jour., vol. 66, 1898, p. 491; Merrill, George P.j Ann. Rept. U.S. Nat. Mus., 1899, pp. 340, 348; Slosson, E. E., Tenth Ann. Rept. Wyo. Coll. Agric. and Mech., 1900, Extract, p, 14; Read, Thomas T., Eng. and Min. Jour., vol. 76, 1903, pp. 48, 49; Darton, N. H., Description of Newcastle district: Geologic Atlas U. S., foho No. 107, U. S. Geol. Survey, 1904, pp, 5, 9; Merrill George P., The Non- Metallic Minerals, 1904, pp. 233, 243; Fisher, C. A., Bull. U. S. Geol. Surv. No. 260, 1905, pp. 559-563. MINERAL RESOUECES BENTOISTITE. 57 form. Dr. E. E. Slosson, of the University of Wyoming, has recommended its use as a retarder for certain kinds of plaster. Bentonite deposits were observed at many localities in the Bighorn basin, where they usually occur in the Colorado shales about 100 feet below the Mowry beds, although in one locality, near the Silver Tip coal mine, they are reported in beds above the Colorado formation. One of the most extensive deposits of bentonite observed in this district is on Dry Creek, about 8 miles east of Frannie, Wyo. Here the bentonite is in the black shales of the lower part of the Colorado formation, a short distance below the Mowry beds, which are well developed at this place. The deposits have a total thickness of 11 feet, distributed throughout a vertical range of 100 feet. The thickest layer is about 7i feet. Below the bentonite, beds of dark shale abound, and above are lighter shales containing bands of iron concretions. The material at this locality is a gray, fine-grained, massive clay, with green and yellow tints and is apparently of good quality throughout. The thin seams of gypsum, sometimes associated with the clay, are present though not conspicuous. The following section will show the approximate position of the different deposits at this place : Section of a portion of the Colorado formation on Dry Creek, Wyoming. Feet. Bentonite _ 2 Dark fissile shale 12 Bentonite 7J Shale. _ 30 Bentonite _ 1 Shale containing thin layers of bentonite 50 Near the head of Dry Gulch, about 5 miles north of Cowley, Wyo., a IJ-foot layer of bentonite is found near the top of the Colorado formation. The following section shows the materials above and below the clay : . Section taken from head of Dry Gulch, Wyoming. Feet. Black shale capped by brown sandstone 6 Bentonite 1^ Black fissile shale 20 Duriag the last field season deposits of a clay possessing properties similar to bentonite were discovered in the lower part of the coal-bearing measures ; also in the overlying Wasatch formation. Those in the former are associated with thin deposits of coal and coaly shale in sandy beds outcropping at the head of Bud Kimball Draw, 12 miles southeast of Tensleep, Wyo. A section of the deposit is here given: Section of bentonite at head of Bud Kimball Draw, Wyoming. Feet. Brown leaf-bearing sandy shale with streaks of coal _ _ _ 2 Dark-gray clay _ 4 Bentonite . . : . 6 Light-gray clay 6 Gray sandstone with carbonized wood particles 1 Impure coal 1 Gray sand. 58 GEOLOGT AND WATER RESOURCES OF BIGHORN BASIN. In the badlands of the Wasatch formation, on the southern side of Cottonwood Creek, about 10 miles southeast of Meeteetse, an impure bentonite occurs. GYPSUM. The gypsum deposits of the Bighorn basin are mainly in the Chugwater forma- tion. They occur also in the lower part of the Sundance, formation, and at one locality a deposit 8 feet thick was observed in the upper part of the Morrison forma- tion. In the Chugwater red beds there is usually a gypsum layer 30 to 40 feet thick near the top of the formation and generally one of equal thickness at or near its base. Along the southern side of the basin the gypsum at the base of the red beds is absent. Thinner beds of gypsum are found at various horizons in the Chugwater formation, but these appear to be of local deposition. In most places where the gypsum has been carefully examined it is apparently of good quality, though no analyses have been made to determine its exact chemical nature. It is a white, compact, massive variety and generally occurs in beds that are free from partings. The following section, taken on Trail Creek northwest of Cody, will show the position of the gypsum in the upper part of the Chugwater red beds: Section of a portion of the Sundance and underlying Chugwater formation on Trail CreeTc, Wyoming. Feet. Green shale containing thin limestone layers (Sundance) 83 Red sandy shale containing thin layers of gypsum (Chugwater) 12 White massive gypsum_ 30 Red sandstones (red beds). About 10 miles south of Cody a deposit of gypsum was observed in the upper part of the Morrison formation. The following section shows its relative position : Section of a portion of the Morrison and overlying Cloverly for-mation south of Cody, Wyo. Feet. Brown, coarse-grained, cross-bedded sandstone (Cloverly) 60 Reddish sandy shale with thin gypsum layers. _ . 25 White massive gypsum 8 Reddish sandy shale with thin gypsum layers 15 Though there are extensive deposits of gypsum throughout this area no attempt has been made to utilize the product except in a very small way. There is a stucco mill about 10 miles northeast of Windsor post-office, Wyo., in the southern part of Montana, where plaster is manufactured from a gypsum deposit near the base of the Chugwater red beds. The beds mined at this place are about 15 feet thick, and the product is of good quality. The material is ground and placed in ovens, where it is calcined at a red heat in order to drive off the chemically combined water. A retarder is then added to prevent it from hardening too quickly when water is applied. After this it is mixed with hair and placed in barrels ready for shipment. The entire process of converting the gypsum into stucco is relatively simple and inexpensive. The finished product of this mill is sold at Bridger at $12 a ton, but the output is not large. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 53 PL. A. OIL WELL AND DERRICK NEAR BONANZA, WYO. HOT-SPRINGS DEPOSITS AT THERMOPOLIS, WYO. MINERAL EESOUECES. 59 OIL AND GAS. Bonanza oil ^eZ(Z.— Several attempts have been made to obtain oil from the Cretaceous shales throughout the Bighorn basin, but generally without success. About three-fourths of a mile southwest of Bonanza, near the axis and at the northern end of a small anticline in the Colorado formation, several oil seeps furnish a small amount of oil. The oil is from a thin-bedded sandstone underlying the Mowry beds of the Colora,do formation. This surface indication has caused many persons to believe that oil in paying quantities might be obtained by drilling, and consequently several deep borings have been made in this region (PI. XV, A). None of these have been successful, and at present all exploration has ceased. Oil from the Bonanza district has been studied by E. E. Slosson, of the University of Wyoming, and the distillation of the product is given below: Distillation of Bonanza petroleum, a No. Boiling point. Specific gravity. Degree Baum6. Flashing point. Burning point. °C. °F. "C. °F. °C. °F. 60-157 157-200 200-237 237-273 273-297 297-329 329-371 371-391 391-340 140-314 314-392 392-459 459-523 523-567 567-624 624-715 715-736 736-646 .762 .792 .843 .853 .867 .876 .861 .849 .850 53.5 46.5 40.3 34.1 31.4 36.6 34. S 34.6 Below 15 18 38 108 121 46 Below 15 Below 15 19 Below 59 64 100 180 226 250 115 Below 59 Below 59 66 Below 15 36 78 108 132 161 162 52 48 33 91 1 o 280 cm.3 distilled in 10 per cent fractions. A deep boring for oil was made at the mouth of Cottonwood Creek, on Shoshone River, near Cody, Wyo., but no oil was obtained. The well is located on the western slope of a small anticline in Colorado shale. Byron gas Held. — Plans are now being made to sink a deep well on the western side of a broad anticline, along the axis of which a small area of Pierre shale is exposed. Shoshone River crosses the southern end of the anticline and has cut for some dis- tance into the shale. In the low valley of this stream near the center of the anticline there are places where gas escapes in considerable quantity from the alluvial sands. It probably is derived from the underlying shales of the Pierre formation. The gas burns readily, but its quahty was not ascertained. The boring which is now pro- posed will doubtless demonstrate whether or not gas is present in sufficient amount to warrant development. About 3 miles east of Basin, Wyo., a small well is being dug in the Pierre shale for the purpose of finding gas. The present depth of the well is about 100 feet and an appreciable amount of gas has already been obtained. A small company has been organized and the work will be continued. 11774— No. 53—06 5 60 GEOLOGY AND WATEE BESOUECES OF BIGHOEN BASIN. BUILDING STONE. Sandstone. — Several varieties of building stone are found in the various forma- tions exposed in the Bighorn basin, but at present only a small amount is used. These varieties comprise sandstone, limestone, marble, and granite. A sandstone used for building occurs in the upper part of the Benton formation, and in some districts the Cloverly formation furnishes a sandstone of moderate firmness and pleasing color. The Chugwater formation also contains layers of sandstone which, on account of their rich red color, have been used as an ornamental stone. The sandstones of the Laramie and associated formations are generally too soft to be used in construction work. Limestone. ^Lmxestone, although abundant, is not generally used as a building material. A very pure variety of limestone, resembling marble, occxirs at the top of the Madison formation. In the Bighorn Mountains this stone has been quarried for trial. It is of a light-cream color, fine grained, uniform in texture, and apparently of good quahty. Granite. — In Shoshone Canyon, west of Cody, granite is exposed which might prove to be of good quality for building stone. It is a dark gray, moderately coarse- grained variety and appears to be firm and durable. The material is to be used in the large Government dam across Shoshone River, now in course of construction. The later Quaternary gravels along the south side of the Shoshone River Valley have been used by the Burlington and Missouri River Railroad Company as roadbed material. Gravel especially well suited for this purpose is found about 2 miles west of Garland. Here a switch has been built and a large amount of gravel is taken out. The gravels of this region are dark colored, owing to the presence of a large amount of volcanic material. FIRE CLAY. The Cloverly formation throughout this general region has the usual inter- stratified beds of clay and shale which in other districts are of refractory character, suitable for fire clays of good quality. None of these clays throughout the basin have been tested, but it is possible that they may prove to be of good quality. Bald Mountain district. — During the past decade various attempts have been made to develop gold mines in the vicinity of Bald Mountain, but the results have not been encouraging. The gold occurs in the basal gravels of the Deadwood formation, especially where these gravels have been mixed with disintegrated por- tions of the underlying granite and redeposited as a valley filling. The gold is fine grained and free, but values are low and its distribution throuhgout the gravels is apparently irregular. The highest assays reported are $2 a ton, but the amount is usually much less. Bighorn hasin region. — Gold is mined from placers along Clarks Fork, in the vicinity of Clark, and on Shoshone River below the mouth of Alkali Creek. The output has never been large at either of these localities. PROFESSIONAL PAPER NO. 53 PL. A, SHOSHONE RIVER AT CODY HOT SPRINGS. Showing Quaternary gravels and extinct geyser cone. NK HOLE IN GEYSER DEPOSITS. MINERAL EESOUECES. 61 MINERAL WATERS. CODY HOT SPRINGS. Description. — About 3 miles west of Cody, in the bed of Shoshone Kiver, there are a number of warm mineral springs. Formerly springs of this character occurred on both sides of the river, but at present they are confined mainly to the north side, where, along the water's edge, within a distance of about 200 feet, five or six springs are found. The water issues from crevices in Embar limestone immediately under- lying the Chugwater red beds, which here dip eastward at an angle of about 15°. These beds are overlain by a deposit of Quaternary gravel 25 to 30 feet thick, capped by about 20 feet of travertine. Near the middle of the stream is a large spring which flows vigorously and is evidently under considerable pressure. During times of low water this spring is very noticeable, but in the flood season it is entirely covered by the river water. No analysis has been made of the spring water, but it evidently contains a large amount of hydrogen sulphide and probably some sulphuric acid. It is also otherwise considerably mineralized. The water is clear, warm, and emits a strong sulphurous odor. In the warmest spring it has a temperature of 98°. The water is diverted into pipes which lead to a sanitarium, where it is used both for bathing and for medicinal purposes. Closely associated with the springs are vents or crevices in the rock, from which large vohimes of hydrogen-sulphide gas escape, and the limestone immediately surrounding these vents is considerably altered. The geologic structure of this region is relatively simple, as is shown in cross section No. 3 of PI. IV. The springs occur at the lower end of Shoshone Canyon, at the base of Rattlesnake Mountain, which, is a moderately broad anticlinal ridge branching from the front range of the Absaroka Mountains. The anticline has long, gradual slopes on the east and steep dips on the west, and it rises to an altitude of about 8,500 feet. It is noteworthy that the greatest thermal activity has taken place on the side of lowest dips. Shoshone CaWon exposes the structure of the uplift down to and into the crystalline rocks. Hot-spring deposits. — Hot-spring deposits occur at different levels in Shoshone Canyon and at its upper and lower end, far above the present level of the river. On the north side of the river, just below the mouth of Shoshone Canyon, there is a broad travertine terrace covering several acres, and smaller areas are found along the east side of Cedar Mountain from Shoshone River southward for about 2 miles. The distribution of these deposits is shown on the geologic map, PI. III. A number of extinct geyser or hot-spring cones occur. The most prominent of these on the south side of Shoshone River is shown on PI. XVI, A. On the north bank of the river, a short distance north of the sanitarium, there is an empty crater about 70 feet in diameter and 40 feet deep (PI. XVI, B), indicating the position of a hot pool, and a short distance northeast of this there is a smaller crater of similar nature. Source of water. — It is difficult to ascertain definitely the source of water of the Cody hot springs, but the flow is probably not derived from the formation in which the springs occur. Two water-bearing horizons underlie the Embar limestone^ the Tensleep and Deadwood formations — and the water is probably derived from oae of these sources. Under these conditions its only means of escape to the surface 62 GEOLOGY AND WATEE RESOUECES OF BIGHOEN BASIN. is through fractures in the strata along the side of the arch. If the water is derived from the Tensleep formation a very high heat gradient of the earth's crust in this region must be assumed in order to account for the temperature of the spring water, for this formation is not deeply covered by overlying beds between the area where the water passes underground and the point of its reappearance at the springs. If the water comes from a deeper-seated source, such as the Deadwood formation, its temperature can be satisfactorily accounted for. The sandstone at the base of the Deadwood, which is the only water-bearing horizon of the formation, is about 2,200 feet below the surface at the springs. Assuming that the mean annual temperature at Cody is 50° and that there is an increase in temperature of 1° for every 50 feet underground below the first 50 feet, the temperature of the earth's crust at a depth of 2,200 feet would, be about equal to the temperature of the spring water. It seems probable, therefore, that the water of the Cody hot springs is derived from the base of the Deadwood formation and that it rises to the surface under hydrostatic pressure, through fractures in the strata along the base of the Rattlesnake Mountain anticline. THERMOPOLIS HOT SPRINGS. At Thermopolis, on Bighorn River in the southeastern part of the Bighorn basin, there is a hot mineral spring the flow of which has been variously estimated at from 3,000 to 4,000 gallons a minute. Calcium carbonate is the principal ingredient of the water, while magnesium sodium and calcium sulphate are present in smaller amounts. (PI. XV, B, p. 58.) An analysis of this water made by Prof. E. E. Slosson, of the University of Wyoming, is here given : Corn-position of the waters of Thermopolis Hot Springs, Wyoming. SiOz JFcaOa and AljOg KCl Na2S04 4.986 .227 10. 249 15.110 CaSO^ 13. 156 CaCOg 40. 454 NaCl 26. 195 129. 820 MgsSOi 19. 443 There are two sanitariums and a large plunge located near the spring, and the place is rapidly becoming a popular health resort for people of northwestern Wyoming. The Thermopolis hot springs have been described by Mr. N. H. Darton. "■ WARM SPRINGS IN BLACK CANYON. Warm springs are reported from Sheep Canyon in the northeastern part of the basin, and farther up Bighorn River at the upper end of Black Canyon there is a small spring of mineral water which is noticeably warmer than the river water. Sulphur occurs in local deposits on the southern side of Shoshone River, at the lower end of Shoshone Canyon, and along the western side of Sulphur Creek for about 2 miles above its mouth. It was deposited by heated waters and gas from the numerous hot springs that once existed in this region. A large amount of prospect- of the Owl Creek Mountains, etc.: U. S. Senate Doc. No. 119, 59th Congress, 1st session. CLIMATE. 63 ing has been done, and development of this resource is at present being considered. The material appears to be of excellent quality, but there is some doubt whether it occurs in suflEiciently large quantities to warrant extensive development. Sulphur also occurs in hot-spring deposits at Thermopolis, Wyo. CLIMATE. There is a wide range of climate in the Bighorn basin region, corresponding mainly to differences of altitude. On the high mountains surrounding the basin heavy snows usually begin early in September and continue until April, while in the center of the basin snow rarely lies on the ground for any great length of time and only a few days of cold weather occur during the winter months. Very few meteorologic data concerning the climatic features of the mountainous regions are available, but in several places in the basin systematic observations have been made by the Weather Bureau since 1898. The following table gives a record of the monthly and annual mean temperature at Basin, Wyo., for a period of five years, 1898 to 1903, inclusive, with the exception of 1901 : Records of the monthly and annual mean temperature, etc., in round numbers, at Basin, Wyo. Jan. Feb. Mar. Apr. May. June. July. Aug. Sept. Oct. Nov. Deo. Annual. Killing frost. Year. Mean. Extremes. Last in spring. First in autumn. 1898 73 74 78 74 74 41 43 48 49 48 28 34 30 32 30 12 12 27 20 22 Max. Min. 1899 1900 1902 1903 18 14 12 22 2 12 23 16 20 30 36 34 46 45 46 46 55 60 61 55 72 67 70 70 73 73 59 61 42 46 40 46 107 114 107 107 -51 -36 -39 -17 May 5 Apr. 18 May 4 June 9 Sept. 7 Sept. 15 Sept. 18 Average. 16 13 36 46 58 69 74 . 60 46 31 19 45 RAINFALL. There is a moderate amount of rainfall in summer throughout this general region, especially in the mountainous districts, where it has been variously estimated from 30 to 40 inches. On the lower lands in the interior of the basin arid conditions prevail. Here the snowfall is light and the amount of rain small, the average annual precipitation varying from 3 to 10 inches. During the summer there are a few heavy showers, but they are usually of short duration. A record of the monthly and annual precipitation at Basin, Wyo., for a period of six years, 1898 to 1903, inclusive, is given in the following table : 64 GEOLOGY AND WATER EESOURCES OE BIGHORN BASIN. Records of the monthly and annual precipitation at Basin, Wyo. Year. Jan. Feb. Mar. Ap. May. June. July. Aug. Sept. Oct. Nov. Dec. Annual. 1898 i 2.28 0.57 0.58 0.61 0.81 0.80 0.53 0.29 1.46 0.24 0.02 0.10 0.22 0.06 0.05 0.21 . 0.96 0.14 0.27 0.15 0.04 T. 0.06 0.23 0.31 0.25 0.26 1.13 0.38 0.36 0.12 T. T. 0.20 0.00 0.02 0.17 0.03 T. 0.10 0.27 ■T. 0.85 T. 0.06 1899 1.84 0.08 0.00 0.16 ! T. 3.56 T. 0.16 0.14 0.21 1.94 T. T. 0.27 T. 0.13 1.06 0.36 0.85 0.86 9.94 1900 2.91 1901 5.84 1902 2.63 1903 3.78 CULTURE, Settlement here, as elsewhere, is determined by geologic and climatic conditions. Along the larger streams, where water is available, settlements are numerous, while the higher badlands and grazing districts are practically uninhabited. The high mountains on both sides of the Bighorn basin are only thinly populated. The Bighorn Mountains, owing to the heavy snows, the long winters, and the prevalence of frosts during the nights of summer are not suited to farming and they are therefore without permanent inhabitants. During the summer, however, herders, prospectors, and forest rangers live in the mountains, but the season is very short. The same is true of the highlands on the eastern front of the Absaroka, Beartootn, and a portion of the Shoshone mountains. Here, for a short season during the summer, the summit of the range is occupied by ranchmen from the adjoining lowlands. There are a number of medium-sized towns throughout the Bighorn basin. The town of Basin, located on the west side of Bighorn, River in the east-central part of the basin, is a growing place of 600 to 800 inhabitants and the county seat of Bighorn County. It is located on the new branch of the Burlington Eailroad now being built from Frannie to Worland, and is the central trading point for farmers living along a portion of the irrigated valleys of Bighorn and Gray Bull rivers and on Shell and No Wood creeks. The largest town in the basin is Cody, having a population of about 1,200. It is situated in the northwestern part of the district, near the southern ter- mination of the Rattlesnake Mountains. It occupies a central location in a rela- tively large irrigated district, lying along Shoshone River and its more important tributaries. The warm mineral springs near Cody are used considerably for medici- nal purposes and bathing and in consequence attract a few health and pleasure seekers to this place during the summer months. Cody is the base of supplies for the Sho- shone irrigation project, which has its dam and storage reservoir about 5 miles above the town. Thermopolis is the third town in point of size in the Bighorn basin. It is situated on Bighorn River, in the southern part of the district, where it draws a large ranch trade from settlers along the irrigated lands of the neighboring streams. The most attractive feature of the place is the large hot springs which are extensively used for bathing and medicinal purposes and are rapidly becoming a favorite resort for the people of northwestern Wyoming. Meeteetse is a town of about 400 inhabi- tants, located on Gray Bull River in the western part of the basin, in th^ midst of both a grazing and irrigation district. It is the base of supplies for a large mining camp at Kirwin and is a central trading point for the southwestern part of the district. CULTURE. 65 Garland is a small town on the Burlington Kailroad, in the northern part of the district, from which a large amount of freight is hauled to the interior of the basin. A short distance east of Garland are Byron, Cowley, and Lovell, small agricultural towns having a population of from 400 to 500. Worland, the terminus of the new Burlington road, is a growing town of 100 to 200 inhabitants, and along the eastern side of the basin there are several small trading points, including Shell, Bonanza, Hyattville, Tensleep, and Rome. The valley of Shoshone Eiver between Cody and Corbett is thickly settled by farmers. Between Corbett and Garland there are no ranches at present, but during the last year a number of claim shanties have been constructed on the land included under the proposed Government canal. Below Garland, in the vicinity of Byron, Cowley, Lovell, and Ionia, lies the most thickly populated district of the region. There are only a few scattered ranches along Bighorn Eiver below Basin, but farther up a number of thickly populated districts occur and the entire valley is being rapidly settled. Along Shell, Paintroqk, and Tensleep creeks ranches are numerous, and there are a few on Crooked, Beaver, Trapper, Bear, and Alkali creeks. Ranches occur at intervals along No Wood Creek, and on Dry Creek, about 15 miles above its mouth, there is a small German settlement around Germania. Gray Bull Valley is thickly settled throughout its entire course in the basin and on its largest tributary, Wood River, there are a number of well-improved ranches. The valley of Clark Fork, in the northwestern part of the area, is extensively farmed, and a few small places have been located on Newmeyer, Paint, and Pat O'Harra creeks. Along Owl Creek ranches occur at frequent intervals, but along Meeyero, Grass, and Gooseberry creeks they are generally 8 to 10 miles apart. INDEX, Absaroka Mountains, rocks of lO-U, 12, 13-14, 15, 16, 19, 21-23, 25, 27, 28, 29 sections in 22-23 structure of 37-38 topography of 3 Acer Bolanderi, occurrence of 33 Alkali Creek, gold near 60 irrigation on 44 location of 6 rocks on 27 sections on 20, 24, 26 settlement on 65 wells on 43 Alluvium, description of 8, 35-36 Amsden formation, description of 8, 15-16 fossils of 15 section of 15 views of 14 water of 43 Anchor, rocks near 11, 17 Aralia notata, occurrence of 33 radiata, occurrence of 33 whitneyi, occurrence of 33 Artesian wells, possible extent of 43-44 Astarte meeki, occurrence of 23 sp., occurrence of 23 Astartella gurleyi, occurrence of 21 B. Baculites anceps, occurrence of 30 asper, occurrence of 30 sp., occurrence of 32 Ba-kewellia sp., occurrence of 21 Bald Mountain, altitude of 3 dikes near 9 gold near , 60 rocks on 9, 11 Basin, coal near 54 description of 64 irrigation near 44 natural gas near 59 rainfall at 63-64 rocks near '. 30 temperatures at 63 Bear Creek, location of 5 rocks on 16 settlement on 65 Beartooth Mountains, rocks of 19, 25, 28, 33 topography of 3 Beaver Creek, alluvium on 35 fossils on 21 rocks on 27 settlement on 65 Page. Belemnites densus, occurrence of 23, 24 Bell & Diehl. See Diehl & Bell. Bennett Creek, irrigation on 45 location of 7 rocks on 12 Benton group, coal in 46 sandstone in 60 Bentonite, description of 56-57 occurrence of 29, 57-58 Bighorn basin, geologic map of Pocket. sections across, plate showing 8 sides of, columnar sections of, plate showing 10 topography of 4-5 Bighorn Basin Development Co., reclamation by 46 Bighorn County, Wyo., Bighorn basin in 1 Bighorn County canal, construction of 44 Bighorn limestone, description of 8, 12-13 fossils in 13 weathering of, view of 12 Bighorn Mountains, history of 39-40 rocks of , 11, 12-14, 15-17, 23-24, 25, 26, 29, 36 sections in 23-24, 26, 27, 30 structure of 36 topography of 2-3 views on 14, 16 Bighorn River, alluvium on 35 canyon of, altitude of 2 fossils from 17 rocks in 14 coal on 52 course and character of 3,5 flow of, measurements of 5 gravels on 34 hot springs on 62 irrigation on 44 rocks on 19, 21, 28 tributaries of 5 valley of, settlements in 65 wells along 42, 43 Black Canyon, warm springs in 62 Black Mountain, altitude of 3 rocks of 14, 15, 16 structure of .' 37 Blake mine, coal of 48-49 section of 49 Bonanza, Wyo., coal near 46 oil near 59 distillation of 59 oil well and derrick near, view of 58 Branch canal, irrigation from 46 Bridger Mountains, topography of 3 Bud Kimball Draw, bentonite on 57 coal on 53 sections on 53, 57 68 Page. Building stone, occurrence of 60 Burns & Rogers mine, coal of 47 section of 47 Byron, description of 65 irrigation at 44 natural gas near 59 C. Calapoeoia sp., occurrence of 13 Cambrian roclcs, description of 8, 10-11 Cambrian time, history in 40 Camerotoechia herrickana, occurrence of 14 Camptonectes sp., occurrence of 23 Carboniferous rocks, descriptions of 8, 13-18 Carboniferous time, history of 40-41 Cardium speciosura, occurrence of 32 sp., occurrence of 32 Carpites sp., occurrence of 33 Carter Creek, location of 6 Carter Mountain, location of 38 Cedar Creek, rocks on 11 Cedar Mountains, fossils from 18 rocks on 15, 16, 17-18, 19, 25 Chugwater formation, age of 21 deposition of 40-41 description of 8, 18-20 fossils of 21 gypsum in 58 occurrence of 38, 39 sandstone in 60 sections of 19-20, 58 views of 18 Cinchonidium ovata, occurrence of ' 33 Cincinnati canal, irrigation by 44 Clark, Wyo., gold near 60 gravels near 34 Clark Fork, alluvium on 35 canyon of, rooks in .' 27 sections in 20, 25 course and character of 7 gold near 60 gravels on 34 irrigation on 45 rocks on 12, 14, 15 settlement on 65 tributaries of 7 Climate, description of 63-64 Clinker beds, occurrence of 52 Cloud Peak, altitude of 36 Cleverly, Wyo., dikes near 30 rocks near : 27, 29 section near 20, 27 Cloverly formation, coal in 46, 53 deposition of 41 description of 8, 26-28 fire clay in 60 sandstone in ■ 60 sections of 27-28, 28 W3.t6T from 4.3-44 Coal, occurrences of, description of 46-56 sections of 47-56 Cody, Wyo., boring near 59 coal near 47-48 sections of 47 description of 64 gypsum near 58 irrigation near 46 Page. Cody, Wyo., mineral springs at 6 rocks near 27, 30 sections near 22, 25, 47, 58 stream-flow measurements ^t 6 views of and at 2, 6 Cody Coal Company, mine of 47-48 mine of, section of 47 Cody Hot Springs, description of 61-62, 64 Colorado formation, bentonite in 56, 57 coal in 48 deposition of 42 description of 8, 28-30 fossils of 29-30 occurrence of 38-39 oil in 59 section of .■ 57 Conie mine, coal of 48 section of 48 Cookstove basin, rocks on 9 Coon Creek, location of 6 Corbett, Wyo., views near 32,46 Corbula sp., occurrence of 30 Cottle & McDonald. See McDonald & Cottle. Cottonwood Creek, bentonite on 58 boring on 59 location of 5 rocks on 12, 28, 29, 37 Cowley, description of 65 irrigation at 44 rocks near 29, 30 wells near 4.3-44 Crassatella sp. , occurrence of 30 Cretaceous rocks, description of 8, 25-32 Cretaceous time, history in 41-42 Crooked Creek, irrigation from 44 rocks on 21 section on 19 settlement on 65 Crystal, irrigation near 44 rocks near 38 Crystal Creek, location of 5 Culture, description of 64-65 Cyprina sp., occurrence of 23 D. Dakota sandstone, correlation of ; . . . 41 Dalmanella testudinaria, occurrence of 13 Darton, N. H. , fossils collected by 13, 14, 15, 32 on Cloverly formation 26 on Deadwood formation 10 on Embar formation 17 on stratigraphy 8 on structure 36 on Sundance formation 21 on Thermopolis Hot Springs 62 Deadwood formation, deposition of 40 description of 8, 10-11 fbssils of 10 gold in 60 water of 61-62 Deer Creek, rocks on 15 Devil Canyon, rocks in 15 Devonian time, history in 40 Diamond Creek, location of 6 Dicellomus politus, occurrence of 10 Dickie triines, coal of 50 sections at 50, 51 69 Page. Diehl & Bell mine, coal of 53 section at « 54 Dikes, occurrence of 9-10,30 view of 12 Dinorthis pectinella 13 subquadrata 13 Dosinia jurassica, occurrence of 24 Drainage, description of 5-8 Dry Cottonwood Creek, alluvium on 35 description of 5, 7 irrigation on 45 Dry Creek, alluvium on 35 bentonite on 57 coal on 48 irrigation on 46, 47 location of -" 5 rocks on 27, 30 section on 57 settlement on - 65 view on 32 Dry Gulch, bentonite on 57 section on 57 Duncom Mountain, altitude of 3 E. Eades mine, coal of 52 section of 52 Eaglenest Creek, location of 6 Embar, coal near 51 rocks near 17,28 wells near 43 Embar formation, description of 8,17-18 fossils of 17-18 occurrence of .^. . 39 section of 17 Enchostoma sp., occurrence of 18 Equisetum sp., occurrence of 33 Erskin's inine. coal of 49 Euraetria verneuiliana, occurrence of 14 Eumicrotis curta, occurrence of 23,24 F. Faults, occurrence of 12 Favosites sp. , occurrence of 13 Fenestella sp., occurrence of 18 Ficus sp., occurrence of 33 Fire clay, occurrence of 60 Five Forks Creek, rocks on 12 Five Springs Creek, location of 5 Formations, description of 9-36 distribution of, map showing Pocket. table of 8 Fort Union beds, correlation of 32 Fortunatus Mill, rocks near 10, 11 Fossils. See formation names, individual fossils, etc. Fox Hills sandstone, correlation of 32 Frannie, Wyo., bentonite near 57 rocks near 38 wells near 44 Frost Ridge, altitude of 4 Gapen & Rogers. See Rogers & Gapsn. Garland, coal near description of gravel from Page. Garland, rocks near 38 wells near 42 Garland Coal Company, mine of 55 mine of, section of 55 Garland Flats, area and location of 4 Gas, natural, occurrence of 59 Geologic history, outline of 39-42 Geologic map of Bighorn basin Pocket. Geology, account of 8-42 Germania, irrigation near 46 settlement at 65 wells near 42 Geysers, cone of, view of 60 deposits of 60 See also Hot Springs. Girty, G. H., fossils identified by 17,18,21 Glauconite, occurrence of 11 Gold, occurrence of 11,60 Gonlobasis tenera, occurrence of 34 Gooseberry Creek, alluvium on 35 coal on 50 description of 7 irrigation on 45 rocks of : 28 settlements on 65 Granite, description of 8, 9-10 occurrence of 9-10, 60 Grass Creek, coal near 50 irrigation on 45 settlements on 65 Gravels, terrace, description of 8 utilization of 60 Gray Bull River, alluvium on 35 coal on 48, 49 course and character of 6-7 flow measurements of 6 irrigation on 45 tributaries of 6-7 valley of, character of 4 settlements in 65 view on 2 wells along 42, 43 Gryphsea calceola var. nebrascensis, occurrence of 2*' 24 Gypsum, occurrence of 25,58 Gypsum Creek, wells on 44 H. Hague, A., on Jefferson limestone 12 Halysites catenulatus, occurrence of 13 Hanover canal, construction of 44 Heart Mountain, altitude of 3 rocks on 14, 30, 33, 37 structure of 37 Historical geology, outline of 39-42 Holopea e.xcelsa, occurrence of 13 Honeycombs, location of 5 rocks in 33 Horse Creek, fossils from 24 orchards on 45 rocks on 12, 14, 15, 16 sections on 24 Hot springs, deposits of, description of 8, 61 deposits of, views of 58,60 source of 61-62 Hunt Mountain, altitude of 3 rocks of 12 Huronia sp., occurrence of 13 70 I. Page. Ilo Ridge, altitude of 5 Inoceramus acutilineata, occurrence of 30 f ragilis, occurrence of 30 sp., occurrence of - 30 Ionia, irrigation near : 45 wells near 43 Irma Flats, irrigation on 46 Irrigation, extent of 44-46 map showing 44 J. Jefferson limestone, correlation of 12 Jones mine, coal of 52 Jurassic rocks, description of 8, 21-24 Jurassic time, history in 41 K. Kane, Wyo., fossils from near 21 irrigation near 44 Kirby Creek, alluvium on 35 description of 5, 8 rocks on 30-31 Knight, W. C, on bentonite 56 Knowlton, F. H., fossils identified by 32-33 L. Laevidentalium canna, occurrence of 18 Landslides, occurrence of 11 Laramie formation, age of 32 coal in 46, 50 deposition of 42 description of 8,31-32, 60 view of 32 water from 42, 43 Leda sp., occurrence of 18 Leptaena unicostata, occurrence of 13 Limestone, occurrence of 60 Line Creek, irrigation on 45 location of 7 rocks on 12, 31 Liospira sp., occurrence of 13 Little Bald Mountain, altitude of 3 rocks of 11 Little Canyon Creek, wf Us on 43 Little Rocky Creek, Irrigation on 45 location of 7 rocks on 12 Little Sheep Mountain, altitude of 4 structure of 38 Livingston formation, correlation of 32 Lovell, Wyo., description of 65 irrigation near 45 rocks near 19 Lovell Irrigation Company, canal of 44-45 Lygodium kaulfusii, occurrence of 33 Lyosoma powelli, occurrence of 23 M. McCulloch teak, altitude of 3 fossils near 33 rocks of 33 McDonald & Cottle, coal mine of 52 coal mine of, section of 52 views at : . 52 Mactra sp., occurrence of 32 Madison limestone,deposition of 40 Page. Madison limestone, description of 8, 13-14 fossils of i4 occurrence of 37,38 utilization of 60 views of 12, 14 Map, geologic, of Bighorn basin Pocket. Map, irrigation, of Bighorn basin 44 Mecklen, G. N., coal mine of, description and section of. 54 Medicine Mountain, altitude of 3 fossils from 13 rooks of 11 Meeteetse, Wyo., bentonite near 58 coal near 48-52 sections of 48, 49, 50, 51, 52 description of 64 irrigation near 45 stream-flow measurements at 6 structure near 39 wells near 43 Meeteetse Creek, coal on 48 location of 7 Meeteetse rim, altitude of 4 coal on 48 Meeyero Creek, aUuvium on 35 description of 7 settlements on ' 65 Metoicoceras gibbosus, occurrence of 30 whitei, occurrence of 30 Middleton, Wyo., coal near 52 Mineral resources, descriptions of 46-63 Mineral waters, description of 61-62 Modiola sp., occurrence of 21, 23 Montana, map of part of, showing area described 2 Montana and Wyoming Oil Company, borings of 44 Morgan's ranch, Wyoming, flow measurement at 7 Morrison formation, deposition of 41 description of 8, 25-26 sections of 25-26, 58 Mowry beds, occurrence of 29,57 Mud Creek, wells on 43 Myalina perattenuata, occurrence of 18 swallowi, occurrence of 21 sp., occurrence of 18 My tilus sp., occurrence of 21 N. Natural gas, occurrence of -59 Navine mine, coal of 47 Nerinea sp., occurrence of 23 Neritina sp., occurrence of 23 Newmeyer Creek, alluvium on 35 irrigation on 45 location of 7 settlement on 65 No Water Creek, alluvium on 35 description of 5, 8 rock&on 30-31 No Wood Creek, alluvium on 35-36 coal on 46, 53-54 description of 7 flow measurement of 7 gravels on 34 irrigation on 45 rocks on 38 settlement on 65 view on 16 wells on 42 Nuoula sp., occurrence of 23 71 °- Page. on, distillation of 59 occurrence of 59 Oil well and derrick, view of ' 58 Ordovician rocks, character of -. 8, 12-13 Ordovician time, history in 40 Orr mine, coal of 48 Orthotetes inaequalis, occurrence of 14 Osborn and Wortman, on Waaatch fossils 33 Ostrea engelraanni, occurrence of 24 strigilcula, occurrence of 23, 24 sp., occurrence of 23,24 Otter Creek, wells on 43 Owl Creek, alluvium on 35 course and character of 7 fossils from 32-33 gravels on 34 irrigation on 45 rocks on 17 sections near 20, 24, 25, 28 settlements on 65 tributaries of 7 wells on 42,43 Owl Creek Mountains, rocks on 9, 10, 11, 13, 14, 16, 17, 25, 28 section in 28 topography of 3 Oxydiscus sp., occurrence of 13 P. Paint Creek, alluvium on 35 irrigation on 45 location of 7 settlement on 65 Paintrock Creek, alluvium on 35 gravel on 34 irrigation on. 45 settlements on 65 Parkman formation , correlation of 32 Pat O'Harra Creek, alluvium on 35 gravels on .■ 34 location of ' 7 rocks on 12, 37 settlement on 65 Pentacrinus asteriscus, occurrence of 23 Pholadomya papyracea, occurrence of 30 Pierre shale, bentonite in 56 deposition of 42 description of 8, 30-31 natural gas in 59 Pitchfork ranch, Wyo., view near 2 Platanus sp., occurrence of 33 Plectorthis plicatella, occurrence of 13 Pleuronya subellipticus, occurrence of 23 Polecat Creek, fossils from 32 Populus cuneata, occurrence of 33 glandulifera, occurrence of 33 zaddachi, occurrence of 33 Porcupine Creek, dikes on 9 rocks on 9, 12 Protarea sp., occurrence of 13 Pryor Mountain, rocks on 27, 29, 38 structure of 38 Pteria sp., occurrence of 21 Ptychoparia owenia, occurrence of 10 Page. Quaternary rocks, description of 8, 34-36 Quercus olafseni, occurrence of 33 Rainfall, records at Ralston, Wyo., gravels near Rattlesnake Mountain, hot springs at. .. rocks on 10, 12, 14, 15, structure of Rawhide Creek, location of Read, T. T., on bentonite Red beds. See Chugwater formation. Red Gulch, section in Relief, description of Rhipidomella michelini, occurrence of. . . Rogers & Burns. See Burns & Rogers. Rogers & Gapen, coal mine of, descriptio 3,17-18,19,21,27,2 Rhynchotrema capax, occurrence of . Sage Creek, coal on location of rocks on and near wells on Sandstone, occurrence of , Sandstone dikes, occurrence of Sapindus obtusif olius, occurrence of Scaphites ventricosus, occurrence of Schizodus symmetricus, occurrence of . . . wheeleri , occurrence of Sohuchert, Charles, fossils identified by.. Sections, diagrammatic, plates showing. Seminula humilis, occurrence of Serpula sp., occurrence of Sheep Canyon, warm springs in Sheep Mountain, altitude of dikes near rocks of structure of vicinity of, topography of Shell, Wyo., rooks near sections near view near Shell Creek, alluvium on description of fossils from gravels on irrigation at rocks on 9, section on settlements on Shoshone Mountains, rocks of structure of topography of Shoshone River, alluvium on boring on canyon of, granite from rooks in sections in views in course and character of dam site on, view of Ho w of , measurements of fossils from , 12-13, 14, 16, 21, 27 , 15, 16 15,17 12,14 3,6 6 6 30 72 Page. Shoshone River, gold on 60 gravels on 34, 60 hot springs on ; 61 irrigation on 44-45, 46 reclamation project on 46 reservoir site on, view of 46 rocks on 9, 10 sulphur on 62 tributaries of 6 valley of, settlements in 65 views of and on ■. 6, 32, 46, 60 Silurian time, history in 40 Silver Tip mine, bentonite near 57 coal of, description and section of 56 Slosson, E. E., on bentonite 57 on Bonanza oil 59 on Thermopolis Hot Springs 62 Smith mine, coal of 51-52 South Beaver Creek, dikes on 9 Spirifer centronatus, occurrence of 14 Spring Creek, location of 7 wells on 43 Squaw Buttes, altitude of 5 fossils from 34 Stanton, T. W., fossils identified by 22-23,24,30,32,34 Stinkingwater River. See Shoshone River. Stratigraphy, description of 8-36 table showing 8 Streptelasma sp., occurrence of 13 Stromatocerium sp., occurrence of 13 Structure, description of 36-39 diagram showing 36 Sulphur, occurrence of 62-63 Sulphur Creek, fossils from near 18 location of 6 sulphur on 62 Sundance formation, description of 8 fossils of , 22-24 gypsum in 58 sections of 22-24, 68 Sunshine, rocks near 31 Sunshine Gulch, coal in 51 Syringothyris carter!, occurrence of 14 T. Tancredia sp., occurrence of 23 Tatman Mountain, altitude of 5 coal on 34 gravels on 34 Temperature, records of 63 Tensleep, Wyo., bentonite near 57 iTensleep Creek, alluvium on 35 gravels on 34 irrigation on 45 settlements on 65 Tensleep sandstone, deposition of 40 description of 8, 16-17 views of 16 waterof 43,61-62 Terrace gravels. See Gravels, terrace. Tertiary rocks, description of 8,32-34 Tertiary time, history in 39-40, 42 Thermopolis, Wyo., coal near 52-53 description of 64 hot springs at 62 analysis of water from : 62 deposits ol, view of 58 Page Thermopylis, Wyo., rocks near 17, 28 section near 20 steam-flow measurements at 5 structure near 39 sulphur at 63 Three Forks limestone, occurrence of 12 Topography, description of 1-8 Trail Creek, alluvium on 35 fossils from 23 gypsum on 58 location of 6 sections on 22, 25, 58 Trapper Creek, alluvium on 35 rooks on 14, 21 section on 23 settlement on 65 Travertine, occurrence of 61 Triassic rocks, description of 8, 18-21 Trigonia americana, occurrence of 23 conradi, occurrence of 23 elegantissima, occurrence of 23 montanaensis, occurrence of 23 Trochonema robbinsi, occurrence of 13 Trout Creek, rooks on 15 Turritella sp., occurrence of 30 U. Ulrich, E. 0., fossils determined by 13 Underground water, supply of 42-44 Unio haydeni, occurrence of 34 V. Vetter's coal opening, section of 51 Viviparus wyomingensis, occurrence of 34 Volcanic rocks, description of 8, 32 W. Wasatch formation, bentonite in 57-58 deposition of 42 description of 8, 33-34, 37 fossils of 33-34 view of 32 Washakie Needles, altitude of 2, 38 Water, underground, supply of 42-44 Water resources, description of 42^6 Waters, mineral, descriptions of 61-62 Wells, artesian, possible extent of , 43-44 Wells, shallow, distribution of 42 West Pass Creek, rocks on 12 Whistle Creek, location of 6 White Creek, rocks on 14 Willow Creek, location of 5 Winchester, irrigation near 44 Windsor, Wyo., gypsum near 58 stucco mill near S8 Wood River, alluvium on ^ 35 coal near 49, 51 course and character of 6 rocks on 28 settlement on 65 Woodruff mme, coal of 49 Worland, Wyo., description of 65 W ortman and O sborn , on W asatch fossils 33 Wyoming, map of part of, showing area described 2 Wyoming Coal and Fuel Co., mine of, description and section of 55 CLASSIFICATION OF THE PUBLICATIONS OF THE UNITED STATES GEOLOGICAL SURVEY. [Professional Paper No. 53.] The serial publications of the United States Geological Survey consist of (1) Annual Reports, (2) Monographs, (3) Professional Papers, (4) Bulletins, (5) Mineral Resources, (6) Water-Supply and Irrigation Papers, (7) Topographic Atlas of the United States— folios and separate sheets thereof, (8) Geologic Atlas of the United States — folios thereof. The classes numbered 2, 7, and 8 are sold at cost of publication; the others are distributed free. A circular giving complete lists may be had on application. Most of the above publications may be obtained or consulted in the following ways: 1. A limited number are delivered to the Director of the Survey, from whom they may be obtained, free of charge (except classes 2, 7, and 8), on application. 2. A certain number are delivered to Senators aud Representatives in Congress, for distribution. 3. Other copies are deposited with the Superintendent of Documents, Washington, D. C, from whom they may be had at practically cost. 4. Copies of all Government publications are furnished to the principal public libraries in the large cities throughout the United States, where they may be consulted by those interested. The Professional Papers, Bulletins, and Water-Supply Papers treat of a variety of subjects, and the total number issued is large. They have therefore been classified into the following series: A, Economic geology; B, Descriptive geology; C, Systematic geology and paleontology; D, Petrography and mineralogy; E, Chemistry and physics; F, Geography; G, Miscellaneous; H, Forestry; I, Irriga- tion; J, Water storage; K, Pumping water; L, Quality of water; M, General hydrographic investiga- tions; ISr, Water power; 0, Underground waters; P, Hydrographic progress reports. This paper is the ninety-first in Series B, and the fifty-seventh in Series 0, the complete lists of which follow. (PP=Professional Paper, B=Bulletin, WS=Water-Supply Paper.) SERIES B, DESCRIPTIVE GEOLOGY. B 23. Observations on the junction between the Eastern sandstone aud the Keweenaw series on Keweenaw Point, Lake Superior, by R. D. Irving and T. C. Chamberlin. 1885. 124 pp., 17 pis. (Out of stock.) B 33. Notes on geology o£ northern California, by J. S. Diller. 1886. 23 pp. (Out o£ stock.) B 39. The upper beaches and deltas of Glacial Lake Agassiz, by Warren Upham. 1887. 84 pp., 1 pi. (Out of stock.) B 40. Changes In river courses in Washington Territory due to glaciation, by Bailey Willis. 1887. 10 pp., 4 pis. (Out of stock.) B 45. The present condition of knowledge of the geology of Texas, by R. T. Hill. 1887. 91 pp. (Out of stock.) B 53. The geology of Nantucket, by N. S. Shaler. 1889. 55 pp. , 10 pis. (Out of stock. ) B 57. A geological reconnaissance in southwestern Kansas, by Robert Hay. 1890. 49 pp., 2 pis. B 58. The glacial boundary in western Pennsylvania, Ohio, Kentucky, Indiana, and Illinois, by G. P. Wright, with intro- duction by T. G. Chamberlin. 1890. 112 pp., 8 pis. (Out of stock. ) B 67. The relations of the traps of the Newark system in the New Jersey region, by N. H. Darton. 1890. 'Jl pp. (Out of stock.) B 104. Glaciation of the Yellowstone Valley north of the Park, by W. H. Weed. 1893. 41 pp., 4 pis. B108. A geological reconnaissance in central Washington, by I. C. Russell. 1893. 108 pp., 12 pis. (Out of stock.) B 119. A geological reconnaissance in northwest Wyoming, by G. H. Eldridge. 1894. 72 pp., 4 pis. B 137. The geology of the Fort Riley Military Reservation and vicinity, Kansas, by Robert Hay. 1896. 35 pp., 8 pis. B 144. The moraines of the Missouri Coteau aud their attendant deposits, by J. E. Todd. 1896. 71 pp., 21 pis. B 158. The moraines of southeastern South Dakota and their attendant deposits, by J. E. Todd. 1899. 171 pp., 27 pis. B159. The geology of eastern Berkshire County, Massachusetts, by B. K. Emer.son. 1899. 139 pp., 9 pis. B 165. Contributions to the geology of Maine, by H. S. Williams and H. E. Gregory. 1900. ' 212 pp., 14 pis. I II SERIES LIST. WS 70. Geology and water resources of the Patrick and Goshen Hole quadrangles in eastern Wyoming and western Nebraska, by G. I. Adams. 1902. 50 pp., 11 pis. B 199. Geology and water resources of the Snake River Plains of Idaho, by I. C. Russell. 1902. 192 pp., 25 pis. PP 1. Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of the geology of south- eastern Alaska, by A. H. Brooks. 1902. 120 pp., 2 pis. PP 2. Reconnaissance of the northwestern portion of Seward Peninsula, Alaska, by A. J. Collier. 1902. 70 pp., 11 pis. PP 3. Geology and petrography of Crater Lake National Park, by J. S. Diller and H. B. Patton. 1902. 167 pp., 19 pis. PP 10. Reconnais.sance from Fort Hamlin to Kotzebue Sound, Alaska, by way of Dall, Kanuti, Allen, and Kowak rivers, by W. C. Mendenhall. 1902. 68 pp., 10 pis. PP 11. Clays of the United States east of the Mississippi River, by Heinrich Ries. 1903. 298 pp., 9 pis. PP 12. Geology of the Globe copper district, Arizona, by F. L. Ransome. 1903. 168 pp., 27 pis. PP 13. Drainage modifications in southeastern Ohio and adjacent parts of West Virginia and Kentucky, by W. G. Tight. 1903. 111pp., 17 pis. B 208. Descriptive geology of Nevada south of the fortieth parallel and adjacent portions of California, by J. E. Spurr. 1903. 229 pp., 8 pis. B 209. Geology of Ascutney Mountain, Vermont, by R. A. Daly. 1903. 122 pp., 7 pis. WS 78. Preliminary report on artesian basins in southwestern Idaho and southeastern Oregon, by I. C. Russell. 1903. 51 pp., 2 pis. PP 15. Mineral resources of the Mount Wrangell district, Alaska, by W. C. Mendenhall and F. C. Schrader. 1903. 71 pp., 10 pis. PP 17. Preliminary report on the geology and water resources of Nebraska west of the one hundred and third meridian, by N. H. Darton. 1903. 69 pp., 43 pis. ^ B 217. Notes on the geology of southwestern Idaho and southeastern Oregon, by I. C. Russell. 1903. 83 pp., 18 pis. B 219. The ore deposits of Tonopah, Nevada (preliminary report) , by J. E. Spurr. 1903. 31 pp., 1 pi. PP 20, A reconnaissance in northern Alaska in 1901, by F. C. Schrader. 1904. 139 pp., 16 pis. PP 21. The geology and ore deposits of the Bisbee quadrangle, Arizona, by F. L. Ransome. 1904. 168 pp., 29 pis. WS 90. Geology and water resources of part of the lower James River Valley, South Dakota, by J. E. Todd and C. M. Hall. 1904. 47 pp., 23 pis. PP 25. The copper deposits of the Encampment district, Wyoming, by A. C. Spencer. 1904. 107 pp., 2 pis. PP 26. Economic resources of the northern Black Hills, by J. D. Irving, with contributions by S. F. Emmons and T. A. Jaggar, jr. 1904. 222 pp., 20 pis. PP 27. A geological reconnaissance across the Bitterroot Range and Clearwater Mountains in Montana and Idaho, by Waldemar Lindgren. 1904. 122 pp., 15 pis. PP 31. Preliminary report on the geology of the Arbuokle and Wichita mountains in Indian Territory and Oklahoma, by J. A. Taff, with an appendix on reported ore deposits in the Wichita Mountains, by H. F. Bain. 1904. 97 pp., 8 pis. B 235. A geological reconnaissance across the Cascade Range near the forty-ninth parallel, by G. 0. Smith and F. C. Calkins. 1904. 103 pp., 4 pis. B 236. The Porcupine placer district, Alaska, by C. W. Wrigkt. 1904. 35 pp., 10 pis. B 237. Igneous rocks of the Highwood Mountains, Montana, by L. V. Pirsson. 1904. 208 pp., 7 pis. B 238. Economic geology of the lola quadrangle, Kansas, by G. I. Adams, Erasmus Haworth, and W. R. Crane. 1904. 83 pp., 1 pi. PP 32. Geology and underground water resources of the central Great Plains, by N. H. Darton. 1905. 433 pp., 72 pis. WS 110. Contributions to hydrology of eastern United States, 1904; M. L. Fuller, geologist in charge. 1905. 211 pp., 5 pis. B 242. Geology of the Hudson Valley between the Hoosic and the Kinderhook, by T. N. Dale. 1904. 63 pp., 3 pis. PP 34. The Delavan lobe of the Lake Michigan Glacier of the Wisconsin stage of glaciation and associated phenomena, by W. C. Alden. 1904. 106 pp., 15 pis. PP 35. Geology of the Perry Basin in southeastern Maine, by G. O. Smith and David White. 1905. 107 pp., 6 pis. B 243. Cement materials and industry of the United States, by E. C. Eckel. 1905. 395 pp., 15 pis. B 246. Zinc and lead deposits of northeastern Illinois, by H. F. Bain. 1904. 56 pp., 5 pis. B 247. The Fairhaven gold placers of Seward Peninsula, Alaska, by F. H. MoflSt. 1905. 85 pp., 14 pis. B 249. Limestones of southwestern Pennsylvania, by F. G. Clapp. 1905. 52 pp., 7 pis. B 250. The petroleum fields of the Pacific coast of Alaska, with an account of the Bering River coal deposit, by G. C. Martin. 1905. 65 pp., 7 pis. B 251. The gold placers of the Fortymile, Birch Creek, and Fairbanks regions, Alaska, by L. M. Prindle. 1905. 16 pp., 16 pis. WS. 118. Geology and water resources of a portion of east-central Washington, by F. C. Calkins. 1905. 96 pp., 4 pis. B 252. Preliminary report on the geology and water resources of central Oregon, by I. C. Russell. 1905. 138 pp., 24 pis. PP 36. The lead, zinc, and fluorspar deposits of western Kentucky, by E. O. Ulrich and W. S. Tangier Smith. 1905. 218 pp., 15 pis. PP 38. Economic geology of the Bingham mining district of Utah, by J. M. Boutwell, with a chapter on areal geology, by Arthur Keith, and an introduction on general geology, by S. F. Emmons. 1905. 413 pp., 49 pis. PP 41. The geology of the central Copper River region, Alaska, by W. C. Mendenhall. 1905. 133 pp., 20 pis. B 254. Report of progress in the geological resurvey of the Cripple Creek district, Colorado, by Waldemar Lindgren and F. L. Ransome. 1904. 36 pp. B255. The fluorspar deposits of southern Illinois, by H. Foster Bain. 1906. 75 pp., 6 pis. B 256. Mineral resources of the Elders Ridge quadrangle, Pennsylvania, by R. W. Stone. 1905. 85 pp., 12 pis. B 257. Geology and paleontology of the Judith River beds, by T. W. Stanton and J. B. Hatcher, with a chapter on the fossil plants, by F. H. Knowlton. 1905. 174 pp., 19 pis. SERIES LIST. Ill PP42. Geology of the Tonopah mining district, Nevada, by J. E. Spurr. 1905. 295 pp., 24 pis. WS 123. Geology and underground water conditions of the Jornada del Muerto, New Mexico, by C. R. Keyes. 1905. 42 pp., 9 pis. 'WS 136. Underground waters of Salt River Valley, Arizona, by W. T. Lee. 1905. 194 pp., 24 pis. PP 43. The copper deposits of Clifton-Morenci, Arizona, by Waldemar Lindgren. 1905. 375 pp., 25 pis. B 265. Geology of the Boulder district, Colorado, by N. M. Fenneman. 1905. 101 pp., 5 pis. B 267. The copper deposits of Missouri, by H. F. Bain and E. 0. Ulrich. 1905. 52 pp., 1 pi. PP 44. Underground water resources of Long Island, New York, by A. C. Veatch and others. 1905. 394 pp., 34 pis. WS 148. Geology and water resources of Oklahoma, by C. N. Gould. 1905. 178 pp., 22 pis. B 270. The configuration of the rock floor of Greater New York, by W. H. Hobbs. 1905. 96 pp., 5 pis. B 272. Taconic physiography, by T. M. Dale. 1905. 52 pp., 14 pis. PP 45. The geography and geology of Alaska, a summary of existing knowledge, by A. H. Brooks, with a section on climate, by Cleveland Abbe, jr., and a topographic map and description thereof.by R.M. Goode. 1905. 327 pp., 34 pis. B 273. The drumlins of southeastern Wisconsin (preliminary paper), by W.C. Alden. 1905. 46 pp., 9 pis. PP 46. Geology and underground water resources of northern Louisiana and southern Arkansas, by A. C. Veatch. 1906. — pp., 51 pis. PP 49. Geology and mineral resources of part of the Cumberland Gap coal field, Kentucky, by G. H. Ashley and L. C. Glenn, in cooperation with the State Geological Department of Kentucky, C. J. Norwood, curator. 1906. 239 pp., 40 pis. PP 50. The Montana lobe of the Keewatin ice sheet, by F. H. H. Calhoun. 1906. 62 pp., 7 pis. B 277. Mineral resources of Keuai Peninsula, Alaska: Gold fields of the Turnagain Arn^ -jion, by F. H. Moffit, and the coal fields of Kachemak Bay region, by R. W. Stone. 1906. 80 pp., 18 pis. WS 154. The geology and water resources of the eastern portion of the Panhandle of Texas, by C. N. Gould. 1906. 64 pp., 15 pis. B 278. Geology and coal resources of the Cape Lisburne region, Alaska, by A. J. Collier. 1906. 54 pp., 9 pis. B 279. Mineral resources of the Kittanning and Rural Valley quadrangles, Pennsylvania, by Charles Butts. 1906. — pp., 11 pis. B 280. The Rampart gold placer region, Alaska, by L. M. Prindle and F. L. Hess. 1906. 54 pp., 7 pis. B 282. Oil fields of the Texas-Louisiana Gulf coastal plain, by N. M. Fenneman. 1906. 146 pp., 11 pis. WS 157. Underground water in the valleys of Utah Lake and Jordan River, Utah, by G. B. Richardson. 1906. 81 pp., 9 pis. PP 51. Geology of the Bighorn Mountains, by N. H. Darton. 1906. 129 pp., 47 pis. WS 158. Preliminary report on the geology and underground waters of the Roswell artesian area, New Mexico, by C. A. Fisher. 1906. 29 pp., 9 pis. PP 52. Geology and underground waters of the Arkansas Valley in eastern Colorado, by N. H. Darton. 1906. 90 pp., 28 pis. WS 159. Summary of underground- water resources of Mississippi, by A. F. Crider and L. C. Johnson. 1906. 86 pp., 6 pis. PP 53. Geology and water resources of the Bighorn basin, Wyoming, by Cassius A. Fisher. 1906. 72 pp., 16 pis. SERIES 0, UNDERGROUND WATERS. WS 4. A reconnaissance in southeastern Washington, by I. C. Russell. 1897. 96 pp., 7 pis. (Out of stock.) WS 6. Underground waters of southwestern Kansas, by Erasmus Haworth. 1897. 65 pp., 12 pis. (Out of stock.) WS 7. Seepage waters of northern Utah, by Samuel Fortier. 1897. 60 pp., 3 pis. (Out of stock.) WS 12. Underground waters of southeastern Nebraska, by N. H. Darton. 1898. 56 pp., 21 pis. (Out of stock.) WS 21. Wells of northern Indiana, by Frank Leverett. 1899. 82 pp., 2 pis. (Out of stock. ) WS 26. Wells of southern Indiana (continuation of No. 21), by Frank Leverett. 1899. 64 pp. (Out of stock.) WS 30. Water resources of the Lower Peninsula of Michigan, by A. C. Lane. 1899. 97 pp., 7 pis. (Out of stock.) WS 31. Lower Michigan mineral waters, by A. C. Lane. 1899. 97 pp., 4 pis. (Out of stock.) WS 34. Geology and water resources of a portion of southeastern South Dakota, by J. E. Todd. 1900. 34 pp., 19 pis. WS 53. Geology and water resources of Nez Perces County, Idaho, Pt. I, by I. C. Russell. 1901. 86 pp., 10 pis. WS 54. Geology and water resources of Nez Perces County, Idaho, Pt. II, by I. C. Russell. 1901. 87-141 pp. WS 55. Geology and water resources of a portion of Yakima County, Wash., by G. O. Smith. 1901. 68 pp., 7 pis. WS 57. Preliminary list of deep borings in the United States, Pt. I, by N. H. Darton. 1902. 60 pp. (Out of stock.) WS 59. Development and application of water in southern California, Pt. I, by J. B. Lippincott. 1902. 95 pp., 11 pis. (Out of stock.) WS60. Development and application of water in southern California, Pt. II, by J. B. Lippincott. 1902. 96-140 pp. (Out of stock. ) WS 61. Preliminary list of deep borings in the United States, Pt. II, by N. H. Darton. 1902. 67 pp. (Out of stock.) WS 67. The motions of underground waters, by C. S. Slichter. 1902. 106 pp., 8 pis. B 199. Geology and water resources of the Snake River Plains of Idaho, by I. C. Russell. 1902. 192 pp., 25 pis. WS 77. Water resources of Molokai, Hawaiian Islands, by Waldemar Lindgren. 1903. 62 pp., 4 pis. WS 78. Preliminary report on artesian basins in southwestern Idaho and southeastern Oregon, by I. C. Russell. 1903. 53 pp., 2 pis. PP 17. Preliminary report on the geology and water resources of Nebraska west of the one hundred and third meridian, by N. H. Darton. 1903. 69 pp., 43 pis. WS 90. Geology and water resources of a part of the lower James River Valley, South Dakota, by J. E. Todd and C. M. Hall. 1904. 47 pp., 23 pis. WS 101. Underground waters of southern Louisiana, by G. D. Harris, with discussions of their uses for water supplies and for rice irrigation, by M. L. Fuller. 1904. 98 pp., 11 pis. WS 102. Contributions to the hydrology of eastern United States, 1903, by M. L. Fuller. 1904. 522 pp. WS 104. Underground waters of Gila Valley, Arizona, by W. T. Lee. 1904. 71 pp., 5 pis. 11774— No. 53—06 6 "-^-^t^y-i. ^^r^ IV SEKIES LIST. WS 106. Water resources of the Philadelphia district, by Florence Basoom. 1904. 75 pp., 4 pis. WSllO. Contributionstothehydrologyof eastern United States, 1904; M. L. Fuller, geologist in charge. 1904. 211 pp., 5 pis. PP 32. Geology and underground water resources of the central Great Plains, by N. H. Darton. 1904. 433pp., 72 pis. ('""■it of stock.) WS 111. Preliminary report on underground waters of Washington, by Henry Landes. 1904. 85 pp., 1 pi. WS 112. Underflow tests in the drainage basin of Los Angeles Kiver, by Homer Hamlin. 1904. 55 pp., 7 pis. WS 114. Underground waters of eastern United States, by M. L. Fuller, geologist in charge. 1904. 285 pp., 18 pis. WS 118. Geology and water resources of east-central Washington, by F. C. Galkins. 1905. 96 pp., 4 pis. B 252. Preliminary report on the geology and water resources of central Oregon, by 1. C. Russell. 1905. 138 pp., 24 pis. WS 120. Bibliographic review and index of papers relating to underground waters published by the United States Geo- logical Survey, 1879-1904, by M. L. Fuller. 1905. 128 pp. WS 122. Relation of the law to underground waters, by D. W. Johnson. 1905. 55 pp. WS 123. Geology and underground water conditions of the Jornada del Muerto, New Mexico, by C. R. Keyes. 1905. 42 pp., 9 pis. WS 136. Underground waters of the Salt River Valley, by W. T. Lee. 1905. 194 pp., 24 pis. B264. Record of deep-well drilling for 1904, by M. L. Fuller, E. F. Lines, and A. C. Veatch. 1905. 106 pp. PP 44. Underground water resources of Long Island, New York, by A. C. Veatch and others. 1905. 394 pp., 34 pis. WS 137. Development of underground waters in the eastern coastal plain region of southern California, by W. C. Menden- hall. 1905. 140 pp., 7 pis. WS 138. Development of underground waters in the central coastal plain region of southern California, by W. C. Menden- hall. 1905. 162 pp., 5 pis. WS 139. Development of underground waters in the western coastal plain region of southern California, by W. C. Menden- hall. 1905. 105 pp., 7 pis. WS 140. Field measurements of the rate of movement of underground waters, by C. S. Slichter. 1905. 122 pp., 15 pis. WS 141. Observations on the ground waters of Rio Grande Valley, by C. S. Slichter. 1905. 83 pp., 5 pis. WS 142. Hydrology of San Bernardino Valley, California, by W. C. Mendenhall. 1905. 124 pp., 13 pis. WS 145. Contributions to the hydrology of eastern United States :M. L. Fuller, geologist in charge. 1905. 220 pp., 6 pis. WS 148. Geology and water resources of Oklahoma, by C. N. Gould. 1905. 178 pp., 22 pis. WS 149. Preliminary list of deep borings in the United States, second edition, with additions, by N. H. Darton. 1905. 175 pp. PP 46. Geology and underground water resources of northern Louisiana and southern Arkansas, by A. C. Veatch. 1906. — pp., 51 pis. WS 153. The underflow in Arkansas Valley in western Kansas, by C. S. Slichter. 1906. 90 pp., 3 pis. WS 154. The geology and water resources of the eastern portion of the Panhandle of Texas, by C. N.;Gould. 1906. 64 pp., 15 pis. WS 1.55. Fluctuations of the water level in wells, with special reference to Long Island, New York, by A. C. Veatch. 83 pp., 9 pis. WS 157. Underground water in the valleys of Utah Lake and Jordan River, Utah, by G. B. Richardson. 1906. 81 pp., 9 pis. WS 158. Preliminary report on the geology and underground waters of the Roswell artesian area. New Mexico, by C. A. Fisher. 1906. 29 pp., 9 pis. PP 52. Geology and underground waters of Arkansas Valley in eastern Colorado, by N. H. Darton. 1906. 90 pp., 28 pis. WS 159. Summary of underground-water resources of Mississippi, by A. F. Crider and L. C. Johnson. 1906. — pp., 6 pis. PP 53. Geology and water resources of the Bighorn basin, Wyoming, by Cassius A. Fisher. 1906. 72 pp., 16 pis. The following papers also relate to this subject: Underground waters of Arkansas Valley in eastern Colorado, by G. K. Gilbert, in Seventeenth Annual, Pt. II; Preliminary report on artesian waters of a portion of the Dakotas, by N. H. Darton, in Seventeenth Annual, Pt. II; Water resources of Illinois, by Frank Leverett, in Seventeenth Annual, Pt. II; Water lesources of Indiana and Ohio, by Frank Leverett, in Eighteenth Annual, Pt. IV; New developments in well boring and irrigation in eastern South Dakota, by N. H. Darton, in Eighteenth Annual, Pt. IV; Rock waters of Ohio, by Edward Orton, in Nineteenth Annual, Pt. IV; Artesian well prospects in the Atlantic coastal plain region, by N. H. Darton, Bulletin No. 138. Correspondence should be addressed to The Director, United States Geological Survey, July, 1906. Washington, D. C. e'E.,STEf{ \ P^ ^Luu^^'^ ; I fe-\ \..^^ D '07