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The Bannock Thrust Zone Southeastern Idaho

Description: Abstract: The Bannock overthrust in southeastern Idaho and northcentral Utah was originally described by Richards and Mansfield (1912) as a single large thrust fault that formed at the close of the Laramide orogeny and was folded by renewed compression near the end of Pliocene time. Later Mansfield expanded and revised his interpretation of the Bannock overthrust so that at least the northern part of the overthrust was thought to be a thrust zone in which the individual faults originated in a folded sole thrust. Detailed mapping in areas critical to Richards and Mansfield's interpretations has shown that the faults thought by them to be parts of one large thrust are separate faults, and that, although some of the thrust surfaces are curved, they were not folded in Pliocene time but probably were folded during a late stage of the thrusting. Extensions of the Bannock thrust to the north, south, east, and west based upon extrapolation of a single large folded thrust surface are not warranted. The Bannock overthrust is reinterpreted as a westward-dipping imbricate thrust zone possibly several tens of miles wide extending at least from southwestern Montana to north-central Utah. It is recommended that the name "Bannock overthrust" no longer be used, and that this zone of imbricate thrusts in the southeast corner of Idaho be called the Bannock thrust zone. The thrusts range in age from Late Jurassic to post- Early Cretaceous and are progressively younger from west to east; strong regional compressive forces do not appear to have been active in the area as late as Pliocene time. The upper plates of the thrusts moved to the northeast in response to an unknown force. Steep eastward-trending tear faults formed during thrusting probably in response to differential movement among the eastward-moving thrust plates. In Tertiary and Quaternary time ...
Date: 1963
Creator: Armstrong, Frank C. & Cressman, Earle Rupert

Contributions to Astrogeology, 1967-71

Description: From contributions of astrogeology: The principal goal of research in astrogeology is the solution of several cardinal problems of geology...The present volume is the first of a series of professional papers that will describe major results of research in astrogeology.
Date: 1972
Creator: Geological Survey (U.S.)

A Descriptive Catalog of Selected Aerial Photographs of Geologic Features in Areas Outside the United States

Description: From introduction: The U.S. Geological Survey has selected and assembled 67 sets of aerial photographs that illustrate a variety of geologic features in Antarctica, South and Central America, the southwest Pacific, Iran, Japan, the Arabian Peninsula, Pakistan, and mainland China. Contact prints of the photographs composing these sets are available for purchase. Sets of photographs of geologic features in the United States and Puerto Rico are listed in a separate catalog (Denny, C. S., and others, 1968, A descriptive catalog of selected aerial photographs of geologic features in the United States: U.S. Geol. Survey Prof. Paper 590).
Date: 1969
Creator: Warren, Charles R.; Schmidt, Dwight Lyman; Denny, Charles Storrow & Dale, William J.

Duration of Hydrothermal Activity at Steamboat Springs, Nevada, From Ages of Spatially Associated Volcanic Rocks

Description: Abstract: Steamboat Springs is a presently active equivalent of epithermal gold-silver ore-forming systems. Hot-spring sinter deposits contain small amounts of gold, silver, mercury, antimony, and arsenic. Hot-spring activity probably started before extrusion of the basaltic andesite of Steamboat Springs. Old sinter from the Steamboat Springs system occurs in gravels above and below the basaltic andesite. Intense hydrothermal alteration, including almost complete replacement by hydrothermal potassium-feldspar, has affected the basaltic andesite. Three plagioclase separates of differing potassium content from fresh basaltic andesite yielded potassium-argon ages of 2.52 to 2.55 m.y. Basaltic andesite almost completely replaced by potassium-feldspar yielded an age of 1.1 m.y. The source of energy for the thermal convection system is probably a large rhyolitic magma chamber that supplied the pumice and from which the rhyolite domes were emplaced. Sanidine and obsidian from four of the rhyolite domes yielded potassium-argon ages of 1.15 to 1.52 m.y. and obsidian from one of the northeastern domes yielded apparent ages of 2.97 and 3.03 m.y. The data indicate that hydrothermal activity has occurred at Steamboat Springs, possibly intermittently, for more than 2-1/2 m.y. These data agree with other radiogenic age studies indicating 1- and 2-m.y. lifetimes for the hydrothermal systems that generate epithermal gold-silver deposits.
Date: 1979
Creator: Silberman, M. L.; White, D. E.; Keith, T. E. C. & Dockter, R. D.
Location Info:

Foraminifera From the Northern Olympic Peninsula, Washington

Description: From introduction: This report deals with the stratigraphic and ecologic significance of Foraminifera contained in a Tertiary sequence that crops out in the northern part of the Olympic Peninsula, Wash. (pl. 1). The work was done as a part of a program of geologic investigations for oil and gas possibilities conducted by the U.S. Geological Survey.
Date: unknown
Creator: Rau, Weldon W.

General Geology of Central Cochise County, Arizona

Description: From abstract: This report describes the comprising the western two-thirds of the Pearce quadrangle and the eastern two-thirds of the Benson quadrangle of the Geological Survey's Topographic Atlas of the United States and includes about 1,400 square miles in the west-central part of Cochise County, Arizona.
Date: 1956
Creator: Gilluly, James

Geology and Ore Deposits of the Picher Field, Oklahoma and Kansas

Description: From Purpose and Scope of Report: This report presents a detailed description of the ore deposits of the Picher field and all phases of geology having a bearing on their localization, origin, and the search for them. It is based mainly on work done by the U.S. Geological Survey, but it also incorporates pertinent data from published literature, especially from the outstanding work of George M. Fowler and associates, and some unpublished data obtained from the geologic staffs of the mining companies.
Date: 1970
Creator: McKnight, Edwin Thor & Fischer, Richard P.

The Geology and Petrography of Crater Lake National Park

Description: From introduction: The two papers published here refer practically to the whole region included in the National Park. The one. Part I, treats primarily of the geology, the development of the great volcano, Mount Mazama, and its collapse, which gave birth to Crater Lake; the other, Part II, deals with the petrography, and gives a special description of the various rocks occurring in the park.
Date: 1902
Creator: Diller, Joseph Silas & Patton, Horace Bushnell

Geology of the Great Smoky Mountains National Park. Tennessee and North Carolina

Description: From Preface: "The present account summarizes the results of a long investigation of the rocks of the Great Smoky Mountains (1946-55) by geologists of the staff of the U.S. Geological Survey, in collaboration with those of the Tennessee Division of Geology. The technical details of this investigation have already been set forth at length in professional papers of the U.S. Geological Survey. The present account contains the gist of these findings about the rocks of the mountains, and is accompanied by a map and structure sections in which the surface and underground extent of the rocks are displayed."
Date: 1968
Creator: King, Philip Burke; Neuman, Robert B. & Hadley, Jarvis B.

Geology of the Hot Sulphur Springs quadrangle, Grand County, Colorado

Description: Scope and Purpose of Work: The quadrangle was mapped as part of the U.S. Geological Survey program of classifying and evaluating lands in the Public Domain. Mineral rights for coal had been retained in parts or all of Tps. 2 and 3 N., Rs. 77, 78, and 79 W. These areas are in part underlain by sedimentary rocks of Late Cretaceous(?) and early Tertiary age (Middle Park Formation), and in North Park these rocks are called the Coalmont Formation and contain coal. The chief purpose of the work was to map and study any coal beds found and to make a detailed geologic map that can be used as part of a geological atlas of the United States.
Date: 1968
Creator: Izett, Glen Arthur

Geology of the Kettleman Hills Oil Field, California: Stratigraphy, Paleontology, and Structure

Description: From Introduction: The field work that furnished the basis for this report was begun in 1930 and was continued at intervals until 1934. The anticlinal character of the Kettleman Hills is apparent to even the casual observer, but the many structural complications due to an intricate network of minor faults, at least in North Dome and Middle Dome, are much less obvious. Though it is improbable that these faults have any relation to the occurrence of oil, an attempt was made to map them, not only to represent the structure adequately but also because the stratigraphy could not be understood if they were neglected. Faunal zones were particularly useful in mapping. On the other hand, some lithologic units proved to be more persistent than had been expected. The two sets of features-fossils and lithology-served as checks on each other.
Date: 1940
Creator: Woodring, W. P.; Stewart, Ralph & Richards, R. W.

Jurassic (Bathonian and Callovian) Ammonites in Eastern Oregon and Western Idaho

Description: From abstract: Jurassic ammonites of late Bathonian to middle Callovian Age have been found in 12,000-13,000 feet (3,660-3,960 m) of strata exposed in the area near and south of Izee and Seneca in east-central Oregon. Ammonites of early Callovian Age and possibly also late Bathonian Age occur in several hundred feet of black shale exposed along Dennett Creek near Mineral, Idaho. Early Callovian ammonites also occur in similar black shale exposed on the Oregon side of Snake River Canyon about 32 miles (52 km) south of the northeast corner of Oregon.
Date: 1981
Creator: Imlay, Ralph W.

The Lyon Station-Paulins Kill Nappe : the Frontal Structure of the Musconetcong Nappe System in Eastern Pennsylvania and New Jersey

Description: From abstract: Geologic and aeromagnetic data show that a major tectonic unit underlies rocks of the Musconetcong nappe in the Great Valley of eastern Pennsylvania and New Jersey. This structure, the Lyon Station-Paulins Kill nappe, can be traced from Lyon Station, Pa., at least to Branchville, N.J., a distance of about 120 km. The nappe has a core of Precambrian crystalline rocks as shown by an aeromagnetic anomaly that has the same signature as the outcropping Precambrian rocks of the Musconetcong nappe. This core extends at least 70 km east from Lyon Station to Bangor, Pa., the eastern limit of the aeromagnetic survey. This report details the frontal structure of this system.
Date: 1978
Creator: Drake, Avery Ala, Jr.

Mineralogy and Stratigraphy of the Lower Part of the Pierre Shale, South Dakota and Nebraska

Description: From abstract and introduction: Mineralogic and stratigraphic studies of the lower part of the Pierre Shale of Late Cretaceous age along the Missouri River indicate correlations different from those generally accepted. The purposes of this paper are to present evidence for the new correlations and to resolve problems of formal nomenclature that result from them.
Date: 1965
Creator: Schultz, Leonard Gene

Mollusca From the Miocene and Lower Pliocene of Virginia and North Carolina: Part 1. Pelecypoda

Description: Abstract: A brief sketch of the stratigraphy of the Miocene of Virginia and the Miocene and Pliocene of North Carolina was prepared by Dr. W. C. Mansfield before his death in July 1939. His purpose was "to provide a background of formational nomenclature" for the taxonomic treatment of the molluscan faunas. The physical nature and distribution of the upper Tertiary formations within those States are discussed, characteristic sections given, and diagnostic molluscan species listed. Part 1 of the systematic report covers the Pelecypoda. A monographic treatment is not attempted, but 132 previously known species are considered, and 62 new species and subspecies are described and figured.
Date: 1943
Creator: Gardner, Julia Anna

Mollusca From the Miocene and Lower Pliocene of Virginia and North Carolina: Part 2. Scaphopoda and Gastropoda

Description: Introduction: Part 2 of the Systematic Report continues and concludes the study of the Mollusca from the Miocene and lower Pliocene of Virginia and North Carolina. One hundred and nineteen species, only a fraction of the known fauna, are reviewed and 66 additional species are described and figured. (See faunal chart, pp. 180-183.) The report upon the gastropods suffers from the same shortcomings obvious in the work on the pelecypods. Most of the material is from old collections made before the importance of the exact placing of the fossil locality both areally and vertically was recognized. Many of the citations of outcrops are vague and the sections generalized. Detailed field studies, particularly on the zoning of the Yorktown formation in southern Virginia and northern North Carolina, were begun later by Wendell P. Mansfield, but he died in the summer of 1939 before the completion of the work.
Date: 1948
Creator: Gardner, Julia Anna & Mansfield, Wendell C.