Search Results

open access

Ancient Lavas in Shenandoah National Park Near Luray, Virginia

Description: 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 … more
Date: 1969
Creator: Reed, John Calvin, Jr.
open access

Pecos National Monument, New Mexico: Its Geologic Setting

Description: From introduction: The ruins of the pueblos and missions of Pecos lie on the east bank of Glorieta Creek near its junction with the Pecos River at the south end of the Sangre de Cristo Mountains in north-central New Mexico. Here the Pecos River and Glorieta Creek have formed a broad rolling valley in which the red adobe walls of the mission church stand as a striking monument to a historic past.
Date: 1969
Creator: Johnson, Ross B.
open access

Gold Veins Near Great Falls, Maryland

Description: 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 … more
Date: 1969
Creator: Reed, John Calvin, Jr. & Reed, John Calvin
open access

Geology of Part of the Craig C-2 Quadrangle and Adjoining Areas, Prince of Wales Island, Southeastern Alaska

Description: 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.
Date: 1961
Creator: Sainsbury, C. L.
open access

Surficial Geology of Mount Rainier National Park, Washington

Description: From introduction: Much of the ground surface around Mount Rainier volcano is directly underlain by loose geologic deposits that veneer the hard rock formations. Examples of these deposits are sand and gravel bars along the rivers, ridges of loose rock debris beside the glaciers, and sloping aprons of rock fragments beneath almost every cliff. Even though they are generally thin and inconspicuous when compared with the rock formations, these surficial deposits are clues to geologic events that.… more
Date: 1969
Creator: Crandell, Dwight Raymond
open access

Geology and Coal Resources of the Salyersville North Quadrangle, Magoffin, Morgan, and Johnson Counties, Kentucky

Description: 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… more
Date: 1963
Creator: Adkison, W. L. & Johnston, J. E.
open access

Bentonite Deposits of the Northern Black Hills District Wyoming, Montana, and South Dakota

Description: 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 Mitte… more
Date: 1962
Creator: Knechtel, Maxwell M. & Patterson, Sam H.
open access

Oxidized Zinc Deposits of the United States: Part 3. Colorado

Description: From abstract: Deposits of oxidized zinc ore are widely distributed in the western part of Colorado in the Rocky Mountains west of the Front Range and in the uplifted plateaus that border the main area of the Colorado Plateau. The principal production and reserves are restricted to several mining districts--Leadville. Aspen, Monarch, Spring Creek. Horseshoe, Tomichi, Tincup, and Rico--in all of which limestone and dolomites of Paleozoic age are the main host rocks. One deposit, that of the Seda… more
Date: 1964
Creator: Heyl, Allen V.
open access

Beryl-bearing Pegmatites in the Ruby Mountains and Other Areas in Nevada and Northwestern Arizona

Description: 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 Cou… more
Date: 1960
Creator: Olson, Jerry C. & Hinrichs, E. Neal
open access

Strategic Graphite, A Survey

Description: From abstract: Strategic graphite consists of certain grades of lump and flake graphite for which the United States is largely or entirely dependent on sources abroad. Lump graphite of high purity, necessary in the manufacture of carbon brushes, is imported from Ceylon, where it occurs in vein deposits. Flake graphite, obtained from deposits consisting of graphite disseminated in schists and other metamorphic rocks, is an essential ingredient of crucibles used in the nonferrous metal industries… more
Date: 1960
Creator: Cameron, Eugene N. & Weis, Paul L.
open access

Geology and Fluorspar Deposits, Northgate District, Colorado

Description: 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 … more
Date: 1960
Creator: Steven, Thomas August
open access

Areal Geology of the Little Cone Quadrangle, Colorado

Description: 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.
Date: 1960
Creator: Bush, Alfred Lerner; Marsh, Owen Thayer & Taylor, Richard B.
open access

Manganese Deposits in the Drum Mountains, Juab and Millard Counties, Utah

Description: 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 o… more
Date: 1961
Creator: Crittenden, Max D., Jr.; Straczek, John A. & Roberts, Ralph Jackson
open access

Geology and Mineral Deposits of the St. Regis-Superior Area, Mineral County, Montana

Description: 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.
Date: 1960
Creator: Campbell, Arthur Byron
open access

Ordovician Graptolites of the Basin Ranges in California, Nevada, Utah, and Idaho

Description: 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.
Date: 1963
Creator: Ross, Reuben James, Jr. & Berry, William B. N.
open access

Oxidized Zinc Deposits of the United States: Part 1. General Geology

Description: 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.)
Date: 1962
Creator: Heyl, Allen V. & Bozion, C. N.
open access

Oxidized Zinc Deposits of the United States: Part 2. Utah

Description: From introduction: This report is compiled from fieldwork and available published data on the oxidized zinc deposits of Utah. Most of the deposits were examined by the author during the autumns of 1952-55 as part of a general study of oxidized zinc deposits of the Western States. In addition, several deposits were visited by geologists of the U.S. Geological Survey as a part of mineral investigation studies since 1940. In the process of obtaining this information many mining companies and indiv… more
Date: 1963
Creator: Heyl, Allen V.
open access

Geology and Mineral Deposits of the Carlile Quadrangle, Crook County, Wyoming

Description: 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 … more
Date: 1961
Creator: Bergendahl, M. H.; Davis, Robert E. & Izett, Glen Arthur
open access

Chromite and Other Mineral Deposits in Serpentine Rocks of the Piedmont Upland, Maryland, Pennsylvania and Delaware

Description: 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 o… more
Date: 1960
Creator: Pearre, Nancy C. & Heyl, Allen V., Jr.
open access

Tertiary Geology and Oil-Shale Resources of the Piceance Creek Basin, Between the Colorado and White Rivers, Northwestern Colorado

Description: From introduction: The greatest known potential oil resource in the world occurs in the oil shale of the Green River formation, and the richest and thickest deposits occur within the area of this report. The purpose of this investigation was to obtain data on the stratigraphic distribution and areal extent of the oil-shale beds and to estimate the potential oil resources in the area.
Date: 1961
Creator: Donnell, John R.
Back to Top of Screen