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- Ancient Lavas in Shenandoah National Park Near Luray, Virginia
- Abstract: In the Blue Ridge Province of northern Virginia, Maryland, and southern Pennsylvania, Lower Cambrian beds are underlain by a thick sequence of greenstone and interbedded sedimentary rocks known as the Catoctin Formation. An area near Luray, Va., was studied to determine the thickness of the formation, its relationship to overlying and underlying rocks, and the original nature of the lavas from which the Catoctin greenstone was derived. There the Catoctin Formation lies unconformably on granitic rocks. Its basal sedimentary layer ranges from a few inches to 150 feet in thickness and contains pebbles of underlying basement rocks. The erosion surface beneath the Catoctin is irregular, and in several places, hills as much as 1,000 feet high were buried beneath the Catoctin lavas. No important time break is indicated between the deposition of the Catoctin Formation and the overlying Cambrian sediments. The original Catoctin lavas were basaltic and were probably normal plateau basalts. Columnar joints, amygdules, sedimentary dikes, flow breccias, low-dipping primary joints, and other primary structures are well preserved.
- Areal Geology of the Little Cone Quadrangle, Colorado
- From abstract: The Little Cone quadrangle includes an area of about 59 square miles in eastern San Miguel County in southwestern Colorado. The quadrangle contains features characteristic of both the Colorado Plateaus physiographic province and the San Juan Mountains, and it has been affected by geologic events and processes of two different geologic environments.
- Bentonite Deposits of the Northern Black Hills District Wyoming, Montana, and South Dakota
- From abstract: The northern Black Hills bentonite mining district includes parts of Crook County, Wyo., Carter County, Mont., and Butte County, S. Dak. Within this district, many beds of bentonite occur interspersed with sedimentary strata of Cretaceous age that have an average total thickness of about 3,000 feet and consist chiefly of marine shale, marl, and argillaceous sandstone. The bentonite beds occur in formations ranging upward from the Newcastle sandstone to the lower part of the Mitten black shale member of the Pierre shale. Tertiary (?) and Quaternary deposits of gravel, sand, and silt are present on extensive terraces, and deposits of such materials also extend along stream courses in all parts of the district.
- Beryl-bearing Pegmatites in the Ruby Mountains and Other Areas in Nevada and Northwestern Arizona
- From abstract: Pegmatite occurs widely in Nevada and northwestern Arizona, but little mining has been done for such pegmatite minerals as mica, feldspar, beryl, and lepidolite. Reconnaissance for beryl-bearing pegmatite in Nevada and in part of Mohave County, Ariz., and detailed studies in the Dawley Canyon area, Elko County, Nev., have shown that beryl occurs in at least 11 districts in the region. Muscovite has been prospected or mined in the Ruby and Virgin Mountains, Nev., and in Mohave County, Ariz. Feldspar has been mined in the southern part of the region near Kingman, Ariz., and in Clark County, Nev.
- Bibliography and Index of U.S. Geological Survey Publications Relating to Coal, 1882-1970
- A bibliography that lists about 1,300 U.S. Geological Survey publications related to coal and published prior to January 1, 1971.
- Bibliography of the Geology and Hydrology of the Albuquerque Greater Urban Area, Bernalillo and Parts of Sandoval, Santa Fe, Socorro, Torrance, and Valencia Counties, New Mexico
- A bibliography which contains over 500 references for the Albuquerque Greater Urban Area (AGUA). The intent is to be comprehensive in scope in the areas of hydrology and geology as well as introductory in other interdisciplinary areas.
- Cenozoic Geology in the Mammoth Area Pinal County, Arizona
- A report about the lower San Pedro Valley in Arizona. This report shows how mapping discrete units of the valley may lead to a broadened understanding of Cenozoic history of intermontane basins in Arizona.
- Cenozoic Geology in the Mammoth Area Pinal County, Arizona
- From introduction: "The purpose of this report is to show how mapping of discrete units of the valley fill may lead to a broadened understanding of Cenozoic history of intermontane basins in Arizona. The area described is in the vicinity of Mammoth Arizona where deep dissection has exposed a complex sequence of terrestrial deposits and related rocks."
- Changes in Stratigraphic Nomenclature by the U.S. Geological Survey, 1963
- A report that fits in a series of reports that are about changes in stratigraphic nomenclature and that will list publications in which the changes have been describes. It deals with stratigraphy, including those defining changes in stratigraphic nomenclature in reports of the U.S. Geological Survey.
- Changes in Stratigraphic Nomenclature by the U.S. Geological Survey, 1969
- A report about the stratigraphic nomenclature changes in geology.
- Changes in Stratigraphic Nomenclature by the U.S. Geological Survey, 1972
- A list of stratigraphic names which are adopted, revised, reinstated, or abandoned are listed. The scheme of the list has been devised simply to facilitate depiction and analyses of the Precambrain history of the United States.
- Changes in Stratigraphic Nomenclature by the U.S. Geological Survey, 1973
- A paper which provides a list of nomenclatural changes. The list also contains publications, the authors, and the names of the reports.
- Changes in Stratigraphic Nomenclature by the U.S. Geological Survey, 1974
- A list of stratigraphic names adopted, revised, reinstated, and abandoned. The nomenclatural changes pertain to geology.
- Changes in Stratigraphic Nomenclature by the U.S. Geological Survey, 1975
- The following document provides a list of publications about geology which relates to nomenclatural changes.
- Chromite and Other Mineral Deposits in Serpentine Rocks of the Piedmont Upland, Maryland, Pennsylvania and Delaware
- From abstract: The Piedmont Upland in Maryland, Pennsylvania, and Delaware is about 160 miles long and at the most 50 miles wide. Rocks that underlie the province are the Baltimore gneiss of Precambrian age and quartzite, gneiss, schist, marble, phyllite, and greenstone, which make up the Glenarm series of early Paleozoic(?) age. These are intruded by granitic, gabbroic, and ultramafic igneous rocks. Most of the ultramafic rocks, originally peridotite, pyroxenite, and dunite, have been partly or completely altered to serpentine and talc; they are all designated by the general term serpentine. The bodies of serpentine are commonly elongate and conformable with the enclosing rocks.
- Chromite Deposits in Central Part Stillwater Complex, Sweet Grass County, Montana
- From abstract: The chromite deposits of the central part of the Stillwater complex lie in a belt 9 miles long between the valleys of Boulder River and the West Fork of the Stillwater River in Sweet Grass County, Mont. The chromite occurs as layers near the middle part of the ultramafic zone in the lower part of the complex. The layers, originally horizontal, have been tilted so that they dip northeastwards at angles ranging from nearly horizontal to nearly vertical, and are cut by many cross faults, the largest with a horizontal offset of 3,000 feet. Investigations by the United States Geological Survey and the United States Bureau of Mines have shown that in this belt there are 5 sections ranging in length from 850 to 3,800 feet along the strike where the continuity and grade of the chromite can be reasonably inferred.
- Chromite Deposits in the Seiad Valley and Scott Bar Quadrangles, Siskiyou County, California
- A report about chromite deposits in the Seiad Creek and McGuffy Creek districts and the Ladd mine, Siskiyou County, California, that occur in dunite-peridotite bodies that are part of an ophiolitic sequence in the western Paleozoic and Triassic belt of the Klamath Mountains.
- The Climax Molybdenum Deposit, Colorado
- From abstract: The largest single metal-mining operation in the history of mining in Colorado has been developed at Climax, as a result of the increased use of molybdenum in the steel and other industries. Production of molybdenum at Climax was notable for a short period during the World War; it ceased from April 1919 to August 1924 but since then has shown a steady increase. In 1930 from 1,000 to 1,200 tons of ore was milled daily, using only one unit of the 2,000-ton mill. The mine has a reserve of broken ore sufficient to furnish 2,000 tons daily for 3 years and is being developed to continue to furnish this and a still further increased output as the use of the metal may warrant.
- Clinoptilolite of Possible Economic Value in Sedimentary Deposits of the Conterminous United States
- A report about clinoptilolite. It is a common zeolite, it is potentially valuable for many industrial and agricultural processes, and it might be useful in controlling water pollution by removing ammonia from wastewater.
- Coal Geology of the White Oak Quadrangle, Magoffin and Morgan Counties, Kentucky
- From abstract: The White Oak quadrangle lies near the western edge of the eastern Kentucky coalfield and includes approximately 59 square miles of parts of Magoffin and Morgan Counties, Ky. The outcropping rocks are equivalent to most of the Breathitt formation of Pennsylvanian age. The regional southeast dip of the rocks is interrupted by the Irvine-Paint Creek fault, the Caney anticline, the Grape Creek syncline, and the Johnson Creek fault.
- Coal Resources of Lawrence County Pennsylvania
- A report about the coal-bearing rocks found in Lawrence County, Pennsylvania. Lawrence County is in west-Central Pennsylvania in the northern part of the Appalachian coal field.
- Coal Resources of Lawrence County, Pennsylvania
- This report records the distribution, thickness, and reserves of coal in Lawrence County, Pennsylvania.
- Coal Resources of the United States
- A report about the United States's coal supply. The U.S. has 25 percent of the world's identified coal resources and about 20 percent of the world's estimated total coal resources.
- The Columbia River Basalt Group in the Spokane Quadrangle, Washington, Idaho, and Montana
- This report studies the several aspects of the basalts in the Columbia River Basalt Group in the Spokane quadrangle, Washington, Idaho, and Montana.
- Construction of Pressure-Temperature Diagrams for Multicomponent Systems After the Method of Schreinemakers--A Geometric Approach
- A report about the Schreinemakers method and the creation of pressure temperature diagrams for multicomponent systems.
- The Contact Mining District, Nevada
- From abstract: This report summarizes the results of a reexamination, in 1930, of the Contact mining district, in Elko County, northern Nevada. A report published as a result of a visit in 1910 summarizes the major features of the geology of the district, and the principal new data in the present paper pertain to mining development occasioned by the completion of a railroad through the camp in 1925.
- Contributions to Economic Geology 1955
- A report about phosphates found in the Permian Phosphoria formation of the Rocky Mountains. This area constitutes one of the worlds largest reserves of phosphate.
- Contributions to General Geology 1951-54
- A report about stratigraphic studies of late Quaternary deposits in the Rocky Mountain region which reveal a widespread uncomformity separating deposits that differ lithologically. The deposits overlying the unconformity contain modern fauna that do not occur in older deposits.
- Copper Deposits of Part of Helvetia Mining District, Pima County Arizona
- A report about the economic geology of four mines located in the Helvetia mining district in the Santa Rita Mountains in south central Arizona. The sedimentary rocks in Helvetia range from Cambrain to Cretaceous.
- Copper Mosses as Indicators of Metal Concentrations
- A report that analyses samples of copper mosses and their substrates and compares these analyses with those published elsewhere.
- Core Drilling for Coal in the Moose Creek Area, Alaska
- From abstract: The Moose Creek area is in the western part of the Matanuska Valley, in south-central Alaska, about 165 miles by railroad north of the coast at Seward. Coal deposits in the valley have been known since the early 1890's, and there have been producing mines since 1916, but the annual production is only about 40,000 tons, or less than one-third of the total amount consumed in the Territory. Early in 1931 Congress authorized the investigation of mineral resources in areas tributary to the Alaska Railroad, which is Government owned and operated, for the purpose of stimulating development and hence increasing the traffic and revenue of the railroad. The technical work of carrying on these studies was entrusted by Col. O. F. Ohlson, general manager of the railroad, to the United States Geological Survey. One of the investigations undertaken was that of the Moose Creek area, where small coal mines are in operation. Difficulties have been encountered in these mines, owing to the faulted character of the formation, which causes unproductive work in mining and also produces a large percentage of fine coal, which is unsuitable for sale in distant markets. Field examination indicated that more favorable mining conditions might be found somewhat farther west. Core drilling was therefore done in 1932, in order to learn if workable beds of coal were present that might he mined at less cost and produce a better product than the present mines for competitive sale in markets of the Pacific coast.
- Correlation Papers: Eocene
- From outline: This essay comprises, first, a general discussion of the limitations of the term Eocene as employed in American geology. The two-fold character of the Tertiary (1. Eocene, 2. Neocene) in America is insisted on. After a somewhat extended review of the literature, in which the various opinions upon disputed points are especially considered, a general study of the stratigraphical, paleontological, and topographical characteristics of the Eocene in the various portions of the country is undertaken.
- Coughs Creek Tongue--A New Tongue of the Eocene Green River Formation, Piceance Creek Basin, Colorado
- A report about the Coughs Creek Tongue which is a sequence of light-gray marlstone, locally containing beds of sandstone and siltstone, in the upper part of the Green River Formation.
- The Crummies Member (New Name) of the Pennsylvanian Breathitt Formation, Eastern Kentucky—Its Distribution and Biostratigraphy
- A report about the Crummies Member of the Breathitt Formation which is a marine unit archaically called the Cannelton Limestone located in the Kanawha River valley of West Virginia.
- The Curry District, Alaska
- From abstract: The Curry district lies on the south flank of the Alaska Range, on the southeast side of Mount McKinley. Most of it is west of the Alaska Railroad. The eastern portion can be easily reached from several points along the railroad route, but the western portion is much more difficult of access, owing to the numerous glacial streams and the rugged topography. The relief of the area is great, the elevation ranging from 500 feet along the Chulitna River to 20,300 feet at Mount McKinley. The Chulitna River, a tributary of the Susitna River, drains the larger part of the area described. It flows in a broad valley in the eastern part of the district, and here the maximum relief is about 3,000 feet. The western part of the district is very rugged, with numerous peaks over 6,000 feet in elevation which have sheer slopes and almost unscalable pinnacles. Winding down through this maze of rugged mountains are four major valley glaciers-Eldridge, Buckskin, Ruth, and Tokichitna-and many tributary and smaller glaciers. Practically the entire district, with the exception of the higher peaks and ridges, has been glaciated. Timber grows along the main streams and extends to an elevation of 2,000 feet, but a large portion of the district lies above that elevation.
- Distribution and Thickness of Devonian Rocks in Williston Basin and in Central Montana and North-Central Wyoming
- A report which includes 200,000 square miles in the southern part of the Williston basin of North Dakota, South Dakota, and Montana. The Devonian rocks consist mostly of marine carbonate, evaporite, and shale beds.
- Distribution and Thickness of Devonian Rocks in Williston Basin and in Central Montana and North-Central Wyoming
- This report studies Devonian rocks in an approximately 200,000-square-mile area between Williston Basin, central Montana, and north-central Wyoming.
- Dolomite Deposit Near Marble Stevens County, Washington
- This report follows the geological field studies of dolomite deposits near Marble Stevens county, Washington.
- The Eagle Valley Evaporite, Northwest Colorado--A Regional Synthesis
- The following report presents a regional study of the extent, thickness, lithology, stratigraphic relations, age, depositional environment, and tectonic history of thick sulfate deposits and associated salts of sodium and potassium.
- Evaluation of the Lead-Alpha (Larsen) Method for Determining Ages of Igneous Rocks
- A report about analyzing the age of igneous rock using its lead-alpha activity.
- Fluorspar Deposits Near Meyers Cove, Lemhi County, Idaho
- Abstract: The fluorspar deposits near Meyers Cove, Lemhi County, Idaho, are localized along three groups of shear zones: one group strikes northeast and dips steeply northwestward, another strikes northeast and dips gently northwestward, and the third strikes northwest and dips gently southwestward. The country rocks are tuffs and flows of the Casto volcanics of Permian(?) age and the Challis volcanics of late Oligocene or early Miocene age. The known deposits are in a belt about 3 miles long and 2 miles wide and crop out at altitudes between 5,100 feet and 7,200 feet above sea level. The principal vein minerals are fluorite, chalcedony, and barite. The fluorite occurs as lodes, crusts around fragments of rock, and replacements of fine breccia. The lodes range in size from veinlets to vein zones several hundred feet long and as much as 20 feet wide and contain ore that ranges in grade from 40 percent to 85 percent CaF2; the average grade is about 50 percent CaF2.
- The Foote Creek and Dutton Creek Formations, Two New Formations in the North Part of the Laramie Basin, Wyoming
- A report about two new geologic formations in Wyoming. The Foote Creek Formation consists of beds of fine-grained sandstone with shale, siltstone, and coal beds. The Dutton Creek Formation consists of beds of coarse-grained locally conglomeratic sandstone.
- The Gabbros and Associated Hornblende Rocks Occurring in the Neighborhood of Baltimore, Maryland
- From introduction: The present paper is intended as a contribution to our knowledge of a particular phase of metamorphism in eruptive rocks, i.e., that one which is dependent on the secondary development of hornblende by the paramorphism or pseudomorphism of pyroxene.
- Geologic Names of North America Introduced in 1936-1955
- A report about geologic names. It contains new names, old names, and changes to names.
- Geologic Reconnaissance Along the Alaska Highway, Delta River to Tok Junction, Alaska
- The following report studies results from the bedrock and surficial geologic reconnaissance of the middle section of the Tanana lowland and adjacent parts of the Alaska Range and the Yukon-Tanana upland.
- Geologic Reconnaissance of the Antelope-Ashwood Area North-Central Oregon
- A report describing the geology of a few counties in Oregon. Strata is exposed that ranges in age from pre-Tertiary to Quaternary.
- Geologic Reconnaissance of the Antelope-Ashwood Area North-central Oregon: With Emphasis on the John Day Formation of Late Oligocene and Early Miocene Age
- From introduction: "This report briefly describes the geology of an area of about 750 square miles in Jefferson, Wasco, Crook, and Wheeler Counties, Oregon."
- Geology and Coal, Oil and Gas Resources of the New Kensington Quadrangle, Pennsylvania
- From abstract: This report is one of a series of publications by the United States Geological Survey on the Appalachian coal, oil, and gas fields. The area described occupies 227 square miles in Allegheny, Butler, and Westmoreland Counties, in western Pennsylvania, immediately north of Pittsburgh.
- Geology and Coal Resources of the Coal-Bearing Rocks of Alabama
- "A detailed estimate of the reserves of coal in Alabama and a description of the stratigraphy of the coal-bearing rocks."
- Geology and Coal Resources of the Henryetta Mining District, Okmulgee County, Oklahoma
- From abstract: The mapped area of the Henryetta mining district includes about 168 square miles in Okmulgee County in the east-central part of Oklahoma. The rocks in this district consist of sandstone, silty shale, and shale, and are divided into the Senora formation and the overlying Calvin sandstone of Pennsylvanian age.