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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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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 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 Salyersville North Quadrangle, Magoffin, Morgan, and Johnson Counties, Kentucky
- From introduction: The U.S. Geological Survey has conducted investigations of the geology and coal resources of the area in and adjacent to the Salyers-ville North quadrangle in the Eastern Kentucky coal field (fig. 7). The Salyersville North quadrangle lies between lat. 3745' and 37052'30'' N., and long. 8300' and 83 07'30'' E.; it is a 71/2-minute quadrangle in the southeast quarter of the Dingus 15-minute area which also includes the Dingus, Lenox, and White Oak 7 -minute quadrangles (fig. 8). The present report is the second for the 15-minute Dingus area; a report by Adkison (1957) has been published for the White Oak quadrangle and a third report is in preparation for the Lenox quadrangle. Other published reports for quadrangles in the vicinity are those by Englund (1955) for Cannel City to the west; Bergin (1962) for Seitz to the southwest; and Hauser (1953) for Paintsville to the east.
- Geology and Fluorspar Deposits, Northgate District, Colorado
- From abstract: The fluorspar deposits in the Northgate district, Jackson County, Colo., are among the largest in Western United States. The mines were operated intermittently during the 1920's and again during World War II, but production during these early periods of operation was not large. Mining was begun on a larger scale in 1951, and the district has assumed a prominent position among the fluorspar producers in the United States. Within the Northgate district, Precambrian metamorphic and igneous rocks crop out largely in the Medicine Bow Mountains, and later sedimentary rocks underlie North Park and fill old stream valleys in the mountains.
- Geology and Mineral Deposits of the Carlile Quadrangle, Crook County, Wyoming
- From introduction: Geologic mapping of the Carlile quadrangle, which includes one of several uranium-producing areas in northeastern Wyoming, was undertaken to provide a detailed geologic map that could be used as an aid to further exploration for uranium deposits; to study in detail the known uranium deposits to determine whether or not there are any relations among structure, stratigraphy, lithology, and uranium deposits; and to outline, insofar as possible, areas favorable for more detailed exploration for uranium.
- Geology and Mineral Deposits of the St. Regis-Superior Area, Mineral County, Montana
- From introduction: The St. Regis-Superior area was studied during the summers of 1953 and 1954 as a part of geologic investigations by the U.S. Geologic Survey in and near the Coeur d'Alene district. The object of the present work was primarily threefold: to ascertain the main structural features in the area, with particular attention to the Osburn fault zone; to investigate the mineral deposits; and to determine the stratigraphic relations of the rocks.
- Geology and Uranium Deposits of the Southern Part of the Powder River Basin, Wyoming
- A report about the Powder River Basin in northeastern Wyoming which is a physiographic unit bounded on the west by the Bighorn Mountains. There are sedimentary rocks which range in age from Cambrian to Oligocene.
- Geology and Uranium Deposits of the Southern Part of the Powder River Basin, Wyoming
- This report follows the geological field studies of uranium deposits near Pumpkin Buttes in the central part of the Powder River Basin, Wyoming, and eventually moving south of the basin.
- Geology of Franklin, Webster, and Nuckolls Counties, Nebraska
- A report about the Geology of three locations in Nebraska. Each location primarily are made up of Shale and chalk of Late Cretaceous age.
- Geology of Franklin, Webster, and Nuckolls Counties, Nebraska
- The following report was prepared as part of a program of the Department of the Interior for the development of the Missouri River basin. The report focuses on the study of the geology of part of south-central Nebraska, with emphasis on the deposits of the Pleistocene age and their engineering characteristics.
- Geology of Part of the Craig C-2 Quadrangle and Adjoining Areas, Prince of Wales Island, Southeastern Alaska
- From abstract: The area mapped is on the east coast of Prince of Wales Island, southeastern Alaska, about 35 miles northwest of the town of Ketchikan. Deposits of magnetite and copper in the mapped area and on Kasaan Peninsula, which adjoins it on the southeast, have been mined for copper and have produced more than 600,000 tons of ore valued at more than $6 million.
- Geology of the Clark Fork Quadrangle Idaho-Montana
- A report about the Clark Fork quadrangle which is underlain by more than 38,000 feet of low-grade metasedimentary rocks of the Precambrian Belt series. The quadrangle has both metallic and nonmetallic mineral deposits of considerable value.
- Geology of the Clark Fork Quadrangle Idaho-Montana
- This report gives a brief geological description of the Clark Fork quadrangle on the Idaho-Montana border.
- Geology of the Duck Creek Pass Quadrangle Montana
- A report about the Duck Creek Pass quadrangle which forms a large part of the bedrock of western Montana and adjoins other areas in which geologic studies are already completed or in progress.
- Geology of the Duck Creek Pass Quadrangle, Montana
- This report follows geological studies of the Duck Creek Pass quadrangle, Montana during the summers of 1956 and 1957.
- Geology of the Jewel Cave Southwest Quadrangle, Custer County, South Dakota
- From introduction: This study was part of the U.S. Geological Survey's continuing study of the geology and ore deposits of the southern Black Hills, which was stimulated by the discovery of uranium deposits in sandstone in the area in 1951 (Page and Redden, 1952; Bell and Bales, 1955).
- Geology of the Lost Creek Schroeckingerite Deposits Sweetwater County, Wyoming
- A report which presents the geologic results of an exploration program in the Lost Creek area by the U.S. Geological Survey in 1951-52 on behalf of the Division of Raw Materials of the U.S. Atomic Energy Commission.
- Geology of the Lost Creek Schroeckingerite Deposits, Sweetwater County, Wyoming
- This report presents the geologic results of an exploration program in the Lost Creek schroeckingerite deposits in northern Sweetwater County, Wyoming.
- Geology of the Northwest Quarter of the Anaconda Quadrangle, Deer Lodge County, Montana
- The following report presents the geology and mineral resources of part of the Anaconda quadrangle near Butte, Montana.
- Gold Veins Near Great Falls, Maryland
- From abstract: Small deposits of native gold are present along an anastomosing system of quartz veins and shear zones just east of Great Falls, Montgomery County, Md. The deposits were discovered in 1861 and were worked sporadically until 1951, yielding more than 5,000 ounces of gold. The vein system and the principal veins within it strike a few degrees west of north, at an appreciable angle to foliation and fold axial planes in enclosing rocks of the Wissahickon Formation of late Precambrian (?) age. The veins cut granitic rocks of Devonian or pre-Devonian age and may be as young as Triassic. Further development of the deposits is unlikely under present economic conditions because of their generally low gold content and because much of the vein system lies on park property, but study of the Great Falls vein system may be useful in the search for similar deposits elsewhere in the Appalachian Piedmont.
- Hawaiian Volcanoes During 1955
- From introduction: "This report continues the systematic account of conditions at Hawaiian volcanoes begun in earlier reports of this series."
- The Helderberg Group and the Position of the Silurian-Devonian Boundary in North America
- A paper that reviews the Helderberg Group and its relation to the Silurian-Devotion boundary.
- Manganese Deposits in the Drum Mountains, Juab and Millard Counties, Utah
- From abstract: The Drum Mountains are in west-central Utah 30 miles northwest of Delta, between the Sevier Desert on the east and Whirlwind Valley on the west. It is a typically barren desert range comprising a westward-tilted structural unit in which is exposed as much as 9,000 feet of quartzite (Cambrian and Precambrian?) and 3,000 feet of carbonate rocks of Cambrian age. These beds, which strike northward and dip west, are cut by myriad east- to northeast trending faults with displacements of a few feet to a few thousand feet. Quartz monzonite dikes, pebble dikes, and vein deposits are present locally along the faults. The Cambrian rocks are overlain unconformably by volcanic rocks of probable Tertiary age.
- Mineral Resources of the Spanish Peaks Primitive Area, Montana
- The following report presents an evaluation of the mineral potential of the Spanish Peaks primitive area, Montana.
- Mineral Resources of the Stratified Primitive Area, Wyoming
- The following report is an evaluation of mineral potential of the Stratified Primitive Area in Wyoming.
- Minerals of Colorado: A 100-Year Record
- A report about the known facts about the minerals that make up the rocks, soils, and ore deposits of Colorado.
- Minerals of Colorado: A 100-Year Record
- "A summary of the first 100 years of published knowledge, including the chief occurrences of 445 mineral species."
- Minor Elements in Bedrock Soil, and Vegetation at an Outcrop of the Phosphoria Formation on Snowdrift Mountain Southeastern Idaho
- This report follows the geochemical study of bedrock soil and vegetation at an outcrop of the Phosphoria Formation of Permian age on Snowdrift Mountain, southeastern Idaho.
- Nomenclature and Correlation of Lithologic Subdivisions of the Jefferson and Three Forks Formations of Southern Montana and Northern Wyoming
- A report about the Jefferson Formation and the Three Forks Formation. Both of them constitute a sequence of dominantly marine rocks.
- Nonopaque Heavy Minerals in Sandstone of Jurassic and Cretaceous Age in the Black Hills Wyoming and South Dakota
- A report about sandstone in the black hills of Wyoming and South Dakota. It discusses the nonopaque heavy minerals found within it.
- Nonopaque Heavy Minerals in Sandstone of Jurassic and Cretaceous Age in the Black Hills, Wyoming and South Dakota
- The following report describes the examinations of the nonopague heavy minerals in sandstone found in the Black Hills in northeastern Wyoming and western South Dakota. The studies were made to determine if differences in the shapes of the grains and proportions of minerals are sufficiently distinctive to be used in subdividing and correlating formations.
- Ordovician Graptolites of the Basin Ranges in California, Nevada, Utah, and Idaho
- From introduction: This report presents a summary of the graptolite faunas of the Basin Ranges as known from the collections of the U.S. Geological Survey and the Departments of Geology of the University of California at Los Angeles and Utah State University. The collections were made in the period 1872-1958, but only a very small number of specimens have been described or illustrated in the 80 or so years elapsed.
- Oxidized Zinc Deposits of the United States: Part 1. General Geology
- From introduction: This report is intended as a descriptive summary. The fieldwork on which it is based was completed in the central Western States in 1952-56, and additional studies were made in the Central and Eastern States before and after the western studies. Research and compilation were completed in 1956-59. Other reports will describe in detail the geology and origin of the oxidized zinc deposits in Colorado, Utah, Nevada, and California. (See also Heyl and Bozion, 1960.)