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At least 973 records · Page 54Linked to original sources
USGS1952

Ground-water data collected in the Missouri River basin units in Kansas during 1951

Ground-water studies in the Missouri River Basin were begun by the United States Geological Survey during the fall of 1945 as a part of the program for development of the resources of the basin by the U.S. Bureau of Reclamation and other Federal Agencies. The studies of the ground-water resources in the part of Kansas that lies within the Basin have been coordinated with the cooperative program of ground-water studies already being made in Kansas by the U.S. Geological Survey, the State Geological Survey of Kansas, the Division of Sanitation of the Kansas State Board of Health, and the Division of Water Resources of the Kansas State Board of Agriculture. Areas in which ground-water data have been collected for the Missouri Basin program include the Almena Unit in Norton and Phillips Counties; the Bostwick Unit in Jewell, Republic, and Cloud Counties; the Cedar Bluff Unit in Ellis, Rush, and Trego Counties; the Glen Elder Unit in Mitchell County; Kanopolis unit in Ellsworth, McPherson, and Saline Counties; Kirwin unit in Phillips, Smith, and Osborne Counties; the Ladder Creek project in Greeley, Gove, Lane, Logan, Scott, Wallace, and Wichita Counties; the St. Francis unit in Cheyenne County; the Webster Unit in Osborne County; and the Wilson Unit in Lincoln County. Data relating to the Ladder Creek project will be published later in a separate report. This report is the fifth of a series of annual reports on ground-water in the above-named units in Kansas and contains the data collected mostly during 1951. An index to the data that were collected and presented in the 1947, 1948, 1949, 1950, and 1951 reports is given in table 1.

Kansas↗
USGS1914

Glaciers of Glacier National Park

Glacier National Park derives its name and much of its interest from the presence of many small glaciers. Very much of the grandeur of its wonderful Alpine scenery, the final sculpturing of the great mountain valleys and of the amphitheaters at their heads, and the production of the basins of its many beautiful lakes are due to the action of the more extended glaciers of the past. There are in the park about 90 small glaciers ranging in size from Blackfeet Glacier, with its 3 square miles of ice, down to masses but a few acres in extent yet exhibiting the characteristics of true glaciers. The most easily accessible of these from the beaten trails are the Blackfeet and Sperry Glaciers and the small glaciers at Iceberg Lake and at Ahern Pass. Some of the others can be reached by tourists who are willing to undergo the exertions of mountain climbing. Among these are Grinnell, Chaney, Shepard, Vulture, and Carter Glaciers, and one or two at Brown Pass. (See map facing page 17.) After examining these features one can easily picture to himself, as he looks down the valleys, the great rivers of ice which in ages past cascaded from the cliffs below the upper cirques, converged as tributaries from the many branch valleys, and united in great trunk glaciers. In imagination lie can see these great glaciers many hundreds of feet ill depth filling the great mountain volleys from side to side, and deploying thence upon the bordering plains. lie seems to see these mighty engines plucking away the rock ribs of the mountains, smoothing, grinding, and polishing the irregularities and sweeping away the debris to be spread on the plains below. These glaciers developed and extended three times and, after each development, the congealed masses melted away on the return of milder climatic conditions, until at length only the small cliff glaciers of the present day are left lurking in the protected recesses at the heads of the capacious valleys. Many of the rock-walled amphitheaters are no longer occupied by ice, but from all there issue streams fed by the melting snow or ice. These plunge over the cliffs in beautiful foaming cascades and rush on down the mountain gorges. The melting glaciers left many inclosed basins large and small, and in these the waters rest a while and mirror in their crystal depths the dark green of the surrounding forests, the rich colors of the rugged mountain walls, and the deep blue of the cloud-flecked sky. On again from lake to lake the waters flow and finally start down their long courses to the sea to merge at length with the chill waters of Hudson Bay, the balm t ides of the Gulf of Mexico, or the rolling billows of the Pacific. Compared in size with the great glaciers of Alaska the glaciers of Glacier National Park are insignificant. They are even surpassed in size by those of the Alps, of the Canadian Rockies, and of Mount Rainier, Washington. They are, however, thought small, among the best examples of this interesting type of phenomena now existing in the United States. They have also a splendid setting in magnificent Alpine scenery, unsurpassed in grandeur anywhere. Hidden away in the recesses of the mighty mountain ranges these rare and wonderful features form a climax to many of the interesting trips open to the tourist.

Montana↗
USGS1952

Stratigraphy and paleontology of the Noatak and associated formations, Brooks Range, Alaska

A think complex sequence of olastic rocks, formerly named the Noatak formation, underlies the Lisburns formation (Mississippian) in the Brooks Range, northern Alaska. Five formations have been recognized as a result of of recent investigations by the author and other geologists of the Navy Oil Unit, U.S. Geological Survey. In the western Brooks Range, the three formations present below the Lisburns formation are: Utukok formation (Upper Touranisian to Lower Visean), Montak formation (restricted) (Upper Devonian to Lower Tournaisian (?)) and Hunt Fork (?) formation (Upper Devonian). In the central Brooks Range the Kayak formation (Lower to Upper Tournaisian), Kanayut formation (Upper Devonian to Lower Tournaisian (?)), and Hunt Fork formation (Upper Devonian) lie below the Lisburns formation. Lithologic and faunal characteristics of these sedimentary units reveal the regional pattern of sedimentation and suggest specific paleoecologic environments. The chart conglomerates in the Kanayut and Noatuk formations are thought to have formed in a belt characterized by fluctuating marine and nonmarine conditions, the chart source being a mid-Devonian ragolith. Analysis of formulas suggest certain correlations with the European, Siberian, and western Cordilleran sections. Described faunas of the Utukok and Kayak formations include 40 braciopod species and varieties, 9 echinodera species, 2 bryzoan species, 8 molluscan species, and 1 tribute species, of which 13 are new.

Alaska↗
USGS1977

The Permian and Triassic Seven Devils Group, western Idaho and northeastern Oregon

Volcanogenic Permian and Triassic rocks in the Snake River Canyon of western Idaho and northeastern Oregon and in the adjacent Seven Devils Mountains of western Idaho are assigned to the Seven Devils Group. New rock-stratigraphic units are the Windy Ridge Formation of probable Early Permian age, the Hunsaker Creek Formation of Early Permian age, the Wild Sheep Creek Formation of Middle and Late Triassic age, and the Doyle Creek Formation of Late Triassic age. The Pittsburg Formation of former usage is abandoned, the rocks being renamed the Kurry Creek Member and assigned to the newly named Doyle Creek Formation. Overlying strata are the Martin Bridge Limestone of Late Triassic age, the Hurwal Formation of Late Triassic age, the Coon Hollow Formation of Middle(?) and Late Jurassic age, and the Columbia River Basalt Group of Miocene age. Underlying rocks are assemblages of metagabbro, metamorphosed quartz diorite, metabasalt, metadiabase, amphibolite, schist, mylonite, and phyllite that are exposed at The Oxbow of the Snake River near Oxbow, Oreg., along a 7-km segment of the Snake River south of Pittsburg Langing, and near the mouth of the Imnaha River. Gabbro, quartz diorite, and rare granodiorite plutons are concentrated in these assemblages, but some also cut the overlying strata. The Seven Devils Group is the result of volcanism, tectonism, and sedimentation that occurred within and near volcanic arcs at converging plate boundaries during the Permian and Triassic Periods. Large parts of these old arcs probably were consumed during later subduction, although direct evidence is lacking in the area considered here.

Idaho, Oregon, Washington↗
USGS1978

Geology and Thermal History of Mammoth Hot Springs, Yellowstone National Park, Wyoming

Mammoth Hot Springs, located about 8 km inside the north entrance to Yellowstone National Park, consists of nearly 100 hot springs scattered over a score of steplike travertine terraces. The travertine deposits range in age from late Pleistocene to the present. Sporadic records of hot-spring activity suggest that most of the current major springs have been intermittently active since at least 1871. Water moving along the Norris-Mammoth fault zone is heated by partly molten magma and enriched in calcium and bicarbonate. Upon reaching Mammoth this thermal water (temperature about 73?C) moves up through the old terrace deposits along preexisting vertical linear planes of weakness. As the water reaches the surface, pressure is released, carbon dioxide escapes as a gas, and bicarbonate in the water is partitioned into more carbon dioxide and carbonate; the carbonate then combines with calcium to precipitate calcium carbonate, forming travertine. The travertine usually precipitates rapidly from solution and is lightweight and porous; however, dense travertine, such as is found in core from the 113-m research drill hole Y-10 located on one of the upper terraces, forms beneath the surface by deposition in the pore spaces of older deposits. The terraces abound with unusual hot-spring deposits such as terracettes, cones, and fissure ridges. Semicircular ledges (ranging in width from about 0.3 m to as much as 2.5 m), called terracettes, formed by deposition of travertine around slowly rising pools. Complex steplike arrangements of terracettes have developed along runoff channels of some hot springs. A few hot springs have deposited cone-shaped mounds, most of which reach heights of 1-2 m before becoming dormant. However, one long-inactive cone named Liberty Cap attained a height of about 14 m. Fissure ridges are linear mounds of travertine deposited from numerous hot-spring vents along a medial fracture zone. The ridges range in height from about 1 to 6 m and in length from a few meters to nearly 300 m; width at the base of a ridge is equal to or greater than its height. In some places, such as along the northern border of Main Terrace, water from new hot-spring activity becomes ponded behind fissure-ridge barriers or dams and deposits travertine that eventually forms large flat terraces.

Bulletin↗
USGS1980

The river and the rocks: The geologic story of Great Falls and the Potomac River Gorge

The Great Falls of the Potomac River has figured prominently in the purposes of men since prehistoric time. Long before John Smith reached the falls in 1609, groups of Indians from East and West met at this great river barrier to trade and perform ceremonies in honor of the spirit of the "Roaring Waters". As early as 1754, George Washington visualized the Potomac River as an important avenue of trade and communication with the interior. Records show that with the exception of Mount Vernon, Great Falls was perhaps as intimately associated with George Washington's everyday life as any other place in the country. As first President of the "Patowmack Canal Company," Washington frequently visited the working parties as they constructed the canal and lock system which skirted the treacherous falls on the Virginia side. Matildaville, a town of about 40 acres named after the wife of "Light Horse" Harry Lee and consisting of various dwellings, grist mill, market house, forge, sawmill, and tavern, sprang up along the banks of the canal. In 1802, the Patowmack Company canals were essentially completed, and hundreds of boats plied the river, bringing corn and wheat, coal and limestone, flaxseed and furs downstream from the mountainous region of Cumberland. Many of the boats were sold for lumber in Georgetown, thus sparing the boatmen an arduous upstream journey. After the establishment of the Nation's Capital, Great Falls became a popular scenic attraction for residents and visitors alike. But Great Falls was not always so easily accessible as it is today. In 1845, a newspaper columnist, after praising the beauty and historic interest of the region, added, "... the access to this interesting spot is, on both sides of the river, by the most infamous of roads and the accommodations for visitors anything but what they ought to be!" Visitors to Great Falls now number close to a half million annually and, because of this continuing and mounting interest, the U.S. Geological Survey has joined with the National Park Service in preparing this booklet for better understanding and enjoyment of the Great Falls of the Potomac River.

Maryland, Virginia↗
USGS1900

A gazetteer of Utah

The Territory of Utah was organized September 9, 1850, its area being a part of that acquired from Mexico by the United States in 1848. As originally organized it extended from the summit of the Rocky Mountains in central Colorado westward to the east boundary of California, including all the territory between the parallels of 37° and 42° north latitude. These limits are thus defined in the act creating the Territory: All that part of the territory of the United States included within the following limits, to wit: Bounded on the west by the State of California, on the north by the Territory of Oregon, and on the east by the summit of the Rocky Mountains, and on the south by the thirty-seventh parallel of north latitude, be, and the same is hereby, created into a temporary government, by the name of the Territory of Utah. The organization of Colorado Territory, in 1861, reduced it on the east to its present eastern boundary, and the formation of the Territory of Nevada, in the same year, reduced it on the west to the meridian of 39° west of Washington. The enabling act of the State of Nevada, passed in 1864, moved the west boundary of Utah a degree farther east, placing it upon the meridian of 38°, and upon the admission of Nevada as a State, in 1866, Utah was still further diminished and Nevada increased, the eastern boundary of the latter being placed upon the meridian of 37° west of Washington. Meantime, in 1863, the northeast corner of the State was cut off and added to the Territory of Idaho, and in 1866 a square degree in the northeast was added to the Territory of Wyoming, thus reducing Utah to its present dimensions. On January 4,1896, it was admitted as a State, its boundaries being the same as those of the Territory of Utah, as follows: Commencing at the intersection of the forty-first parallel of north latitude with the thirty-second meridian west of Washington; thence south on this meridian to the parallel of 37° north latitude; west on this parallel -to the thirty-seventh meridian west of Washington; north on this meridian to the parallel of 42° north latitude; east on this parallel to the meridian of 34° west of Washington; thence south to the forty-first parallel of latitude, and east on this parallel to the place of beginning. The area of the State is 84,970 square miles, of which it is estimated that 2,780 square miles are water surface, including Great Salt, Utah, and other lakes, and 82,190 square miles are land surface.

Utah↗
USGS1999

Ghaba salt basin province and Fahud salt basin province, Oman; geological overview and total petroleum systems

Three Total Petroleum Systems each consisting of one assessment unit have been identified in the Ghaba and Fahud Salt Basin Provinces of north-central Oman. One Total Petroleum System and corresponding assessment unit, the North Oman Huqf/?Q??Haushi(!) Total Petroleum System (201401) and Ghaba- Makarem Combined Structural Assessment Unit (20140101), were identified for the Ghaba Salt Basin Province (2014). In the Fahud Salt Basin Province, however, two overlapping Total Petroleum Systems (TPS) were recognized: (1) the North Oman Huqf?Shu?aiba(!) TPS (201601); Fahud-Huqf Combined Structural Assessment Unit (20160101), and (2) the middle Cretaceous Natih(!) TPS (201602); Natih-Fiqa Structural/Stratigraphic Assessment Unit (20160201). The boundary for each Total Petroleum System also defines the boundary of the corresponding assessment unit and includes all trap styles and hydrocarbon-producing reservoirs within the petroleum system. In both the Ghaba and Fahud Salt Basin Provinces, hydrocarbons were generated from several deeply buried source rocks within the Infracambrian Huqf Supergroup. One general ?North Oman Huqf? type oil is dominant in the Fahud Salt Basin. Oils in the Ghaba Salt Basin are linked to at least two distinct Huqf source-rock units based on oil geochemistry: a general North Oman Huqf-type oil source and a more dominant ?questionable unidentified source? or ?Q?-type Huqf oil source. These two Huqf-sourced oils are commonly found as admixtures in reservoirs throughout northcentral Oman. Hydrocarbons generated from Huqf sources are produced from a variety of reservoir types and ages ranging from Precambrian to Cretaceous in both the Ghaba and Fahud Salt Basin Provinces. Clastic reservoirs of the Gharif and Al Khlata Formations, Haushi Group (middle Carboniferous to Lower Permian), dominate oil production in the Ghaba Salt Basin Province and form the basis for the Huqf/?Q??Haushi(!) TPS. In contrast, the Lower Cretaceous Shu?aiba and middle Cretaceous Natih limestones account for most of the production in the Fahud Salt Basin with about 50 percent of the basin?s production from porous, fractured Shu?aiba limestones in Yibal field, thus the name North Oman Huqf? Shu?aiba(!) TPS. Deep gas is produced mainly from Middle Cambrian to Lower Ordovician clastic reservoirs of the Haima Supergroup. Traps in nearly all hydrocarbon accumulations of these petroleum systems are mainly structural and were formed by one or more 3 mechanisms. These trap-forming mechanisms were mainly periodic halokinesis of the thick Cambrian Ara Salt and consequent folding and faulting from basin loading, rifting, or other major tectonic events, particularly those events forming the Oman Mountains and associated foreland-basin system during the Late Cretaceous and late Tertiary. Many of the future new-field targets will likely be low-relief, subtle structures, as many of the large structures have been drilled. Oman?s recent interest and commitments to liquid natural gas export make deep gas a primary objective in the two North Oman Huqf petroleum systems. New-field exploration of deep gas and exploring deeper targets for gas in existing fields will likely identify a significant gas resource in the next 30 years. Moreover, salt-diapir flank traps in these two North Oman Huqf petroleum systems and salt basin provinces have gone essentially untested and will likely be targeted in the near future. The middle Cretaceous Natih(!) TPS is a small efficient system of the Fahud Salt Basin. Natih source rocks are only mature in the Late Cretaceous/Tertiary foredeep and production is primarily from Natih reservoirs; minor production from the Shu?aiba limestone is documented along fault-dip structures. Most traps are structural and are related to development of the foreland basin and formation of the Oman Mountains. Future targets of the Natih TPS will be less obvious

Bulletin↗
USGS2001

Geology and natural history of the San Francisco Bay area: A field-trip guidebook

A National Association of Geoscience Teachers Far Western Section (NAGT-FWS) field conference is an ideal forum for learning about the geology and natural history of the San Francisco Bay area. We visit classic field sites, renew old friendships, and make new ones. This collection of papers includes field guides and road logs for all of the Bay-area trips held during the NAGT-FWS 2001 Fall Field Conference and supplemental chapters on other aspects of the area’s natural and human history. The trips touch on many aspects of the geology and natural hazards of the Bay area, especially urban problems associated with living on an active tectonic plate margin: earthquake faults, coastal erosion, landslides, and the utilization of land and natural resources. We hope this conference not only provides a two-day learning opportunity for conference participants but that students and educators will use this field guidebook for future teaching and research. Many thanks are due to the U.S. Geological Survey (USGS) and San José State University (SJSU) for cohosting the conference. We are grateful to each of the field trip leaders for preparing the trips and writing the accompanying guides. We especially appreciate the many hours put in by the guidebook reviewers, Robert I. Tilling (USGS) and Paula Messina (SJSU), and to the USGS Western Publications Group for editing, layout, and web posting. Additional guidebook contributions include articles by John Galloway, Scott Starratt, Page Mosier, and Susan Toussaint. During the conference guest speakers include Robert I. Tilling (USGS Volcano Hazards Team) and Ross Stein (USGS Earthquake Hazards Team). Workshops prepared for the conference include GIS in the classroom, using USGS data by John Vogel (USGS) and Paula Messina (SJSU), and The Best of BAESI (Bay Area Earth Science Institute), a teacher training organization under the direction of Ellen Metzger (SJSU) and Richard Sedlock (SJSU). The conference provides an opportunity to showcase USGS scientific and education resources with self-guided tours of the USGS Library, the Earth Science Information Center (ESIC), the Visitor Center, and various laboratories on the USGS campus and includes a half-day participatory tour of the USGS research vessel the R/V Polaris and the USGS Marine Facility at the Port of Redwood City under the direction of Cynthia L. Brown, Francis Parchaso, and Tara Schraga. Beyond the names mentioned above, a host of USGS and SJSU staff, SJSU students, and NAGT-FWS members contributed to the preparation and orchestration of the conference. We couldn’t have done it alone. Leslie C. Gordon (USGS), Philip W. Stoffer (USGS), and Deborah Harden (SJSU) NAGT-FWS 2001 Fall Field Conference Organizers.

California↗
USGS2000

Total petroleum systems of the Illizi Province, Algeria and Libya; Tanezzuft-Illizi

Undiscovered conventional oil and gas resources were assessed within a total petroleum system of the Illizi Province (2056) as part of the U.S. Geological Survey World Petroleum Assessment 2000. The Illizi Province is in eastern Algeria and a small portion of western Libya. The province and its total petroleum system coincide with the Illizi Basin. Although several total petroleum systems may exist within the Illizi Province, only one “composite” total petroleum system is identified. This total petroleum system comprises a single assessment unit. The main source rocks are the Silurian Tanezzuft Formation (or lateral equivalents) and Middle to Upper Devonian mudstone. The total petroleum system was named after the oldest major source rock and the basin in which it resides. The estimated means of the undiscovered conventional petroleum volumes in the Tanezzuft-Illizi Total Petroleum System are 2,814 million barrels of oil (MMBO), 27,785 billion cubic feet of gas (BCFG), and 873 million barrels of natural gas liquids (MMBNGL).

Bulletin↗
USGS2000

Total petroleum systems of the Grand Erg/Ahnet Province, Algeria and Morocco; the Tanezzuft-Timimoun, Tanezzuft-Ahnet, Tanezzuft-Sbaa, Tanezzuft Mouydir, Tanezzuft-Benoud, and Tanezzuft-Bechar/Abadla

Undiscovered, conventional oil and gas resources were assessed within total petroleum systems of the Grand Erg/Ahnet Province (2058) as part of the U.S. Geological Survey World Petroleum Assessment 2000. The majority of the Grand Erg/ Ahnet Province is in western Algeria; a very small portion extends into Morocco. The province includes the Timimoun Basin, Ahnet Basin, Sbaa Basin, Mouydir Basin, Benoud Trough, Bechar/Abadla Basin(s), and part of the Oued Mya Basin. Although several petroleum systems may exist within each of these basins, only seven ?composite? total petroleum systems were identified. Each total petroleum system occurs in a separate basin, and each comprises a single assessment unit. The main source rocks are the Silurian Tanezzuft Formation (or lateral equivalents) and Middle to Upper Devonian mudstone. Maturation history and the major migration pathways from source to reservoir are unique to each basin. The total petroleum systems were named after the oldest major source rock and the basin in which it resides. The estimated means of the undiscovered conventional petroleum volumes in total petroleum systems of the Grand Erg/ Ahnet Province are as follows: [MMBO, million barrels of oil; BCFG, billion cubic feet of gas; MMBNGL, million barrels of natural gas liquids] Total Petroleum System MMBO BCFG MMBNGL Tanezzuft-Timimoun 31 1,128 56 Tanezzuft-Ahnet 34 2,973 149 Tanezzuft-Sbaa 162 645 11 Tanezzuft-Mouydir 12 292 14 Tanezzuft-Benoud 72 2,541 125 Tanezzuft-Bechar/Abadla 16 441 22

Bulletin↗
USGS2000

Total petroleum systems of the Trias/Ghadames Province, Algeria, Tunisia, and Libya; the Tanezzuft-Oued Mya, Tanezzuft-Melrhir, and Tanezzuft-Ghadames

Undiscovered conventional oil and gas resources were assessed within total petroleum systems of the Trias/Ghadames Province (2054) as part of the U.S. Geological Survey World Petroleum Assessment 2000. The Trias/Ghadames Province is in eastern Algeria, southern Tunisia, and westernmost Libya. The province and its total petroleum systems generally coincide with the Triassic Basin. The province includes the Oued Mya Basin, Melrhir Basin, and Ghadames (Berkine) Basin. Although several total petroleum systems may exist within each of these basins, only three “composite” total petroleum systems were identified. Each total petroleum system occurs in a separate basin, and each comprises a single assessment unit. The main source rocks are the Silurian Tanezzuft Formation (or lateral equivalents) and Middle to Upper Devonian mudstone. Maturation history and the major migration pathways from source to reservoir are unique to each basin. The total petroleum systems were named after the oldest major source rock and the basin in which it resides. The estimated means of the undiscovered conventional petroleum volumes in total petroleum systems of the Trias/Ghadames Province are as follows [MMBO, million barrels of oil; BCFG, billion cubic feet of gas; MMBNGL, million barrels of natural gas liquids]: Tanezzuft-Oued Mya 830 MMBO 2,341 BCFG 110 MMBNGL Tanezzuft-Melrhir 1,875 MMBO 4,887 BCFG 269 MMBNGL Tanezzuft-Ghadames 4,461 MMBO 12,035 BCFG 908 MMBNGL

Bulletin↗
USGS2001

Total petroleum systems of the Pelagian Province, Tunisia, Libya, Italy, and Malta; the Bou Dabbous, Tertiary and Jurassic-Cretaceous composite

Undiscovered conventional oil and gas resources were assessed within total petroleum systems of the Pelagian Province (2048) as part of the U.S. Geological Survey World Petroleum Assessment 2000. The Pelagian Province is located mainly in eastern Tunisia and northwestern Libya. Small portions of the province extend into Malta and offshore Italy. Although several petroleum systems may exist, only two ?composite? total petroleum systems were identified. Each total petroleum system comprises a single assessment unit. These total petroleum systems are called the Bou Dabbous?Tertiary and Jurassic-Cretaceous Composite, named after the source-rock intervals and reservoir-rock ages. The main source rocks include mudstone of the Eocene Bou Dabbous Formation; Cretaceous Bahloul, Lower Fahdene, and M?Cherga Formations; and Jurassic Nara Formation. Known reservoirs are in carbonate rocks and sandstone intervals throughout the Upper Jurassic, Cretaceous, and Tertiary sections. Traps for known accumulations include fault blocks, low-amplitude anticlines, high-amplitude anticlines associated with reverse faults, wrench fault structures, and stratigraphic traps. The estimated means of the undiscovered conventional petroleum volumes in total petroleum systems of the Pelagian Province are as follows: [MMBO, million barrels of oil; BCFG, billion cubic feet of gas; MMBNGL, million barrels of natural gas liquids] Total Petroleum System MMBO BCFG MMBNGL Bou Dabbous?Tertiary 667 2,746 64 Jurassic-Cretaceous Composite 403 2,280 27

Bulletin↗
USGS1904

Analyses of rocks from the laboratory of the United States Geological Survey, 1880-1903

The present Geological Survey of the United States was organized in 1879. In 1880 a chemical laboratory was established at Denver, in connection with the Colorado work, in charge of Dr. W. F. Hillebrand, with whom were associated Mr. Antony Guyard and, later, Mr. L. G. Eakins. In 1882 Dr. W. H. Melville was placed in charge of a second laboratory at San Francisco, and in the autumn of 1883 the central laboratory was started in Washington, with myself as chief chemist. In November, 1885, Doctor Hillebrand was transferred to Washington; early in 1888 he was followed by Mr. Eakins, and the Denver laboratory was discontinued. In the spring of 1890 Doctor Melville also was transferred to Washington, and since then the chemical work of the Survey has been concentrated at headquarters. Up to January 1, 1904, over 5,300 analyses have been made in the laboratory at Washington. These represent rocks, minerals, ores, waters, sediments, coals, metals, and so on through all the range of substances with which geology has to do. There were also some hundreds of analyses made in the laboratories at Denver and San Francisco. A fair amount of research work upon mineralogical and analytical problems has also been done. In all of this work the following chemists have been employed: E. T. Allen, Charles Catlett, T. M. Chatard, F. W. Clarke, L. G. Eakins, F. A. Gooch, Antony Guyard, W. F. Hillebrand, W. H. Melville, R. B. Riggs, W. T. Schaller, E. A. Schneider, George Steiger, H. N. Stokes, E. C. Sullivan, William Valentine, and J. E. Whitfield. As many as eight of these have been at work simultaneously; at present only six are connected with the Survey. Other officers of the Survey have been occupied more or less with chemical questions; but the men named in this list were connected directly with the laboratory. Some work for the chemical division has also been done by chemists not regularly on the rolls of the Survey; but their analyses, with the exception of a single group to be noted later, do not fall within the scope of this paper.

Bulletin↗
USGS1915

Analyses of rocks and minerals from the laboratory of the United States Geological Survey, 1880 to 1914

The present Geological Survey of the United States was organized in 1879. In 1880, in connection with the Colorado work, a chemical laboratory was established at Denver in charge of W. F. Hillebrand, with whom were associated Antony Guyard and, later, L. G. Eakins. In 1882 W. H. Melville was placed in charge of a second laboratory at San Francisco, and in the autumn of 1883 the central laboratory was started in Washington, with myself as chief chemist. In November, 1885, Dr. Hillebrand was transferred to Washington; early in 1888 he was followed by Mr. Eakins, and the Denver laboratory was discontinued. In the spring of 1890 Dr. Melville also was transferred to Washington, and since then the geochemical work of the Survey has been concentrated at headquarters. The special laboratories of the water-resources and technologic branches of the Survey are not included in this statement and their work is not represented in this bulletin. Up to January 1, 1914, nearly 8,000 analyses have been made in the laboratory at Washington of rocks, minerals, ores, waters, sediments, coals, metals, and other substances with which geology has to do. Some-hundreds of analyses were also made in the laboratories at Denver and San Francisco. A fair amount of research work upon mineralogical and analytical problems has also been done. In *all of this work the following chemists have been employed: E. T. Allen, R. K. Bailey, Charles Catlett, T. M. Chatard, F. W. Clarke, L. G. Eakins, J. G. Fairchild, F. A. Gooch, Antony Guyard, W. B. Hicks, W. F. Hillebrand, W. F. Hunt, W. H. Melville, H. C. McNeil, Chase Palmer, R. B. Riggs, W. T. Schaller, E. A. Schneider, George Steiger, H. N. Stokes, E. C. Sullivan, William Valentine, R. C. Wells, W. C. Wheeler, and J. E. Whitfield. At present, January 1, 1914, eight of these chemists are employed in the Survey. Other officers of the Survey have been occupied more or less with chemical questions, but the men named in this list were connected directly with the laboratory. Some work for the chemical division has also been done by chemists not regularly on the rolls of the Survey, but their analyses, with the exception of a single group to be noted later, do not fall within the scope of this paper.

Bulletin↗
USGS1915

The fauna of the Batesville sandstone of northern Arkansas

The beds in northern Arkansas that lie between the Boone limestone (commonly regarded as representing the Burlington and Keokuk epochs) and the Pennsylvanian have been divided into several formations, named, in ascending order, Moorefield shale, Batesville sandstone, Fayetteville shale, and Pitkin limestone. These formations presumably are equivalent to those that hold a corresponding position in the typical Mississippian section of Iowa, Missouri, and Illinois, but the faunas which they have furnished show noteworthy differences from the typical faunas. It has therefore seemed desirable to investigate these faunas, especially as the facies which they present is found also in the faunas of several of the Southern States, such as Oklahoma, Mississippi, and Alabama. With this object in view, I published in 1911 a report on the fossils of the Moorefield shale. The fauna next to be considered in a systematic pursuance of such a plan as I have mentioned is that of the Batesville sandstone, but the fauna of the Batesville sandstone, as is well known, has already been described in a treatise by Prof. Stuart Weller. At first I considered the possibility of pretermitting the Batesville fauna and of substituting Prof. Weller's report for my own in a series of little monographs that are under contemplation. It soon became evident, however, that this would not be satisfactory because, whether by reason of having collections from a number of new localities or by reason of having more extensive collections from old ones, I found that the material at my command considerably increased the number of types known from the Batesville sandstone, among them being a few which were undescribed. In fact, while Prof. Weller's paper discusses only 30 species (aside from a few Bryozoan types not even generically distinguished) the present paper discusses 128 species. On this account it seemed to me essential to redescribe the fauna.

Arkansas↗
USGS1940

Transit traverse in Missouri, 1900-1937. Part 6, Northeastern Missouri, 1900-37

This bulletin, which for convenience is to be published in eight parts, contains the results of all transit traverse* done In Missouri through 1937 by the Geological Survey, United States Department of the Interior, including those heretofore published. (See page X.) Each of the parts deals with one of eight sections into which the State has been divided for this purpose and which have been designated northeastern, northwestern, southeastern, southwestern, central, east-central, south-central, and west-central Missouri. In each part descriptions of the points for which geodetic positions have been determined are listed according to the quadrangles in which the points occur. Results of transit traverse other than that done by the Geological Survey have not been included. Northeastern Missouri, as the term is used in this bulletin and as the subject of part 6 of the bulletin, is, as its name indicates, the north-easternmost section of the State. Its north and east boundaries are the boundaries of the State; its west and south boundaries are formed by a line that runs south along longitude 93°15' to latitude 39°30', thence east to longitude 92°00', thence south to latitude 39°15', thence east to the east boundary of the State.

Missouri↗
USGS1953

Fluorspar deposits of the Eagle Mountains, Trans-Pecos Texas

The Eagle Mountains are in the southeastern part of Hudspeth County, Tex., about 17 miles southwest of Van Horn and 100 miles southeast of El Paso, Tex. The fluorspar deposits are in the northern and northeastern parts of the mountains, except for the Rocky Ridge deposits, which are near the center of the mountainous mass. A good all-weather road leads south from Allamoore on U. S. Highway 80 to the mine and mill at Spar Valley. With the exception of the Rocky Ridge deposits, all deposits can be reached by ranch roads from the main Spar Valley road. Fluorspar was first found in the Eagle Mountains in 1919, but no development was undertaken until 1942. Since then, mining has been done at Eagle Spring and at the various deposits in Spar Valley. Many other deposits have been found in the area. About 12,000 tons of fluorspar had been shipped previous to January 1949, most of which came from the North ore body in Spar Valley. A mill was built near the deposits In 1945. With the exception of the Eagle Spring and Tank Canyon deposits, both of minor importance, the fluorspar deposits as of 1950 are all controlled by Texas Fluorspar Mines, Inc., of Van Horn, Tex. Cretaceous sedimentary rocks, which crop out on the flanks of the mountains, are overlain by a thick series of Tertiary volcanics that make up much of the central part of the mountains. Low on the northeast side, the Cretaceous rocks are underlain by Permian (?) limestones and the pre-Cambrian Carrizo Mountain schist. The Cretaceous sedimentary rocks range from the Yucca formation of Early Cretaceous (lower Trinity) age through the Eagle Ford formation of Late Cretaceous age. The rocks on the northeast side of the mountains dip southwest, and those on the southwest and west sides dip east-northeast and northeast. The axis of the large syncline thus formed roughly parallels the axis of the range. The igneous rocks occur within the trough of the syncline. Both intrusive and extrusive rocks are present. The extrusive rocks have been separated into three divisions : the lower rhyolitic series, trachyte porphyry, and the upper rhyolitic series. Both rhyolitic series consist of flows, flow breccias, volcanic breccias, and tuffaceous sediments, all predominantly of rhyolitic composition, although tending toward andesite locally. These volcanics have been intruded by a small stock of syenite, named in this report the Eagle Peak syenite, which crops out in the central, higher parts of the mountains. Rhyolite sills have invaded the sedimentary rocks near the margin of the volcanics, and diabase and late rhyolite dikes have intruded both sedimentary and volcanic rocks. Faults are common in the area, and six series of faults have been recognized. Thrusting from the southwest occurred both before and after the igenous activity and the subsequent downwarping of the central part of the mountains. The early thrust faults were followed by high-angle normal and reverse faults that trend northeastward and cut the volcanics. Later normal and reverse faults trending northwestward, and faults with large horizontal displacements trending roughly eastward, also are present, in addition to very late faults trending in a general northwesterly direction. Fluorspar occurs in the Eagle Mountains both as replacement deposits in limestone and as fissure veins, chiefly in rhyolite. Chief among the fissure veins are those occurring along the Rhyolite fault, the Wind Canyon fault, the vein at Shaft 4, and the veins on Fox claims 9 and 10. The most important replacement deposits are in the Rocky Ridge area and in Spar Valley. • At the North ore body in Spar Valley, the fluorine-bearing solutions replaced a series of sandy limestones in the upper beds of the lower part of the Finlay formation. Structural conditions limited the extent of the replaceable beds and consequently of the fluorspar mineralization. The fluorine-bearing solutions represent a very late stage of the igneous activity of the area. The large east-trending faults with their wide zones of gouge and breccia, typified by the Rhyolite and Wind Canyon faults, acted as the major channels for the solutions in their upward course. From these faults, the solutions spread outward into other faults and fractures, chiefly those with a northeasterly trend, and into the adjoining limestones. The physical and chemical nature of the surrounding rock, as well as structural conditions affecting the presence of openings in the rock, were the major controlling factors governing the size, extent, and position of the fluorspar deposits.

Texas↗