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Recurrent Tropidoleptus Zones of the Upper Devonian in New York

Description: From introduction: This report describes the four zones, three well-marked and one subordinate, in the Upper Devonian rocks, each of which contained several species that are common in the typical Hamilton formation of the Cayuga Lake section and are associated with very few of the really characteristic species of the faunas normal to the formations in which they are found.
Date: 1913
Creator: Williams, Henry Shaler
Partner: UNT Libraries Government Documents Department

Studies of Basin-Range Structure

Description: From preface: This paper represents the partial fruition of a broad plan to reexamine critically the subject of Basin-Range structure.
Date: 1928
Creator: Gilbert, Grove Karl
Partner: UNT Libraries Government Documents Department

The Upper Cretaceous Floras of Alaska

Description: From foreword: This report describes the upper cretaceous floras and rocks south of the Brooks Range in Alaska.
Date: 1930
Creator: Hollick, Charles Arthur
Partner: UNT Libraries Government Documents Department

The Transportation of Débris by Running Water

Description: Abstract: The primary purpose of the investigation was to learn the laws which control the movement of bed load, and especially to determine how the quantity of load is related to the stream's slope and discharge and to the degree of communication of the débris.
Date: 1914
Creator: Gilbert, Grove Karl & Murphy, Edward Charles
Partner: UNT Libraries Government Documents Department

Environmental Geochemical Studies of Selected Mineral Deposits in Wrangell-St. Elias National Park and Preserve, Alaska

Description: From abstract: Environmental geochemical investigations took place in Wrangell-St. Elias National Park and Preserve (WRST), Alaska, between 1994 and 1997. Areas studied include the historic Kennecott stratabound copper mines and mill area; the historic mines and mill in the Bremner district, where gold was produced from polymetallic veins; the sporadically active gold placer mines at Gold Hill; the undisturbed, unmined porphyry copper-molybdenum deposits at Orange Hill and Bond Creek; and the historic mines and mill at Nabesna, where gold-bearing iron skarn deposits were exploited. The cooperative study between the U.S. Geological Survey and the National Park Service focused on identifying and characterizing geochemical signatures associated with these mineralized areas. Sample media included surface water, bedload sediment, rock, mine waste, and mill tailings samples.
Date: 2000
Creator: Eppinger, Robert G.; Briggs, Paul H.; Rosenkrans, Danny S. & Ballestrazze, Vanessa
Partner: UNT Libraries Government Documents Department

Some Middle Cenomanian (Upper Cretaceous) Acanthoceratid Ammonites from the Western Interior of the United States

Description: Abstract: The ammonite family Acanthoceratidae de Grossouvre is represented in the Western Interior region by many genera. Species and subspecies of Calycoceras, Acanthoceras, Cunningtoniceras, Plesiacanthoceras, and Protacanthoceras are important guide fossils to narrow zones of middle Cenomanian age in southeastern Montana, northeastern Wyoming, western South Dakota, and central Kansas. In this region, the ammonite zonation through most of the middle Cenomanian seems to be, from oldest to youngest, a zone of Acanthoceras muldoonense Cobban and Scott, a zone of Acanthoceras bellense Adkins and Calycoceras leonense (Adkins), a zone of Cunningtoniceras amphibolum (Morrow) with subzones of C. amphibolum amphibolum and C. amphibolum fallense (n. subsp.), and a zone of Plesiacanthoceras wyomingense (Reagan). In this report, Acanthoceras muldoonense, A. bellense, and Calycoceras leonense are described from the northern part of the Western Interior for the first time. Cunningtoniceras amphibolum, originally assigned to Acanthoceras, is described in more detail and divided into the nominate subspecies and the new subspecies C. amphibolum fallense. The earliest whorls of Plesiacanthoceras wyomingense, previously unknown, are described as well as all the later growth stages. The small genus, Protacanthoceras, is represented by several new species and one new subspecies. Protacanthoceras fisheri is found in the zone of Acanthoceras bellense, P. vetula occurs in the subzone of Cunningtoniceras amphibolum amphibolum, and P. hosei hosei and P. hosei sheridanense are found in the subzone of C. amphibolum fallense. Protacanthoceras alzadense is associated with Plesiacanthoceras wyomingense.
Date: 1987
Creator: Cobban, William Aubrey
Partner: UNT Libraries Government Documents Department

Runoff Characteristics and Washoff Loads from Rainfall-Simulation Experiments on a Street Surface and a Native Pasture in the Denver Metropolitan Area, Colorado

Description: Abstract: Rainfall simulation studies were conducted in conjunction with the Denver Regional Urban Runoff Program to: (1) Compare runoff quantity and quality from two different intensities of rainfall on impervious plots having identical antecedent conditions, (2) document a first flush of constituent loads in runoff from 1,000-square-foot streetsurface plots, (3) compare runoff characteristics from a street surface subjected to simulated rainfall with those from a 69-acre urban basin of mixed land use subjected to natural rainfall, (4) perform statistical analysis of constituent loads in the runoff with several independent variables, and (5) compare the quantity and quality of runoff from 400-square-foot plots of native grasses used for pasture and subjected to simulated rainfall with that from a 405-acre basin covered with native grasses used for pasture and sub-jected to natural rainfall. The rainfall simulations conducted on the street surface showed that higher intensity simulated rainfall produced a higher percentage of runoff than lower intensity rainfall. A first flush of constituent loads occurred for most constituents in the runoff from most rainfall simulations on the street surface; however, a first flush did not occur in the runoff from simulated rainfall on the pasture. The event mean concentrations of constituents in the runoff from simulated storms on the street surface were generally much smaller than the event mean concentrations of constituents in the runoff from an adjacent urban basin. Analysis of the data from the rainfall simulations on a street surface indicates that intensity of rainfall and total rainfall are important variables determining constituent loads. The design of the experiment was such that intensity of rainfall and total rainfall were highly correlated, thus precluding the development of useful regression equations to predict washoff loads. The quality of runoff from the simulated rainfall on the pasture was influenced by the disturbed perimeters of ...
Date: 1987
Creator: Mustard, Martha H.; Ellis, Sherman R. & Gibbs, Johnnie W.
Partner: UNT Libraries Government Documents Department

Geologic History of the Yosemite Valley

Description: The principal result of the investigations upon which this report is based is the determination within narrow limits of the preglacial depth of the Yosemite Valley and of other facts concerning its preglacial development which permit fairly definite estimates of the proportionate shares of work performed by stream and by glacier. The investigations comprise a detailed survey of the glacial and geomorphologic features of the Yosemite region and an equally intensive study of its rock formations, supplemented by reconnaissance work of both kinds in adjoining parts of the Sierra Nevada.
Date: 1930
Creator: Matthes, François E.
Partner: UNT Libraries Government Documents Department

Geologic History of the Yosemite Valley

Description: The principal result of the investigations upon which this report is based is the determination within narrow limits of the preglacial depth of the Yosemite Valley and of other facts concerning its preglacial development which permit fairly definite estimates of the proportionate shares of work performed by stream and by glacier. The investigations comprise a detailed survey of the glacial and geomorphologic features of the Yosemite region and an equally intensive study of its rock formations, supplemented by reconnaissance work of both kinds in adjoining parts of the Sierra Nevada.
Date: 1930
Creator: Matthes, François E.
Partner: UNT Libraries Government Documents Department

Geology and Ore Deposits of the Park City District, Utah

Description: From introduction: This survey was the first systematic work undertaken in this geologic province since the Geological Exploration of the Fortieth Parallel, in 1869, and was the first detailed geologic examination of a wide area in the Wasatch Range. Hence, an unusual amount of general geologic work in the region surrounding the special field was required to establish fundamental geologic facts.
Date: 1912
Creator: Boutwell, J. M.
Partner: UNT Libraries Government Documents Department

Quaternary Movement Along the La Jencia Fault, Central New Mexico

Description: From abstract: The La Jencia fault is a recently reactivated late Cenozoic basin margin structure of major proportions that forms the western margin of the Rio Grande rift, which borders the eastern sides of the northern Magdalena Mountains and the southern Bear Mountains in central New Mexico. Stratigraphic throw on the fault has not been determined, but Precambrian rocks of the Magdalena Mountains are uplifted a minimum of 800 m (meters) above the adjacent basin floor, below which lie a thick section of upper Cenozoic basin-fill deposits. Most of the implied displacement is probably Neogene in age.
Date: 1988
Creator: Machette, Michael N.
Partner: UNT Libraries Government Documents Department

Yampa Canyon in the Uinta Mountains Colorado

Description: From purpose of the report: A detailed office study of modern topographic and geologic maps and aerial photographs of Yampa Canyon and its environs in the Uinta Mountains.
Date: 1962
Creator: Sears, Julian D.
Partner: UNT Libraries Government Documents Department

The Significance of Geologic Conditions in Naval Petroleum Reserves No. 3, Wyoming

Description: From Introduction: The work on which this report is based consisted of detailed field and office studies which occupied the greater part of the summer of 1927. During this period mapping was done with plane table and telescopic alidade on a scale of 1 inch to 1,000 feet, and wells, faults, and outcrops within the productive part of the Teapot field were located in detail.
Date: 1931
Creator: Thom, W. T., Jr. & Spieker, Edmund M.
Partner: UNT Libraries Government Documents Department

Stratigraphy of Outcropping Permian Rocks in Parts of Northeastern Arizona and Adjacent Areas

Description: From introduction: In the spring and early summer of 1950 the writers undertook an investigation of the outcropping Permian rocks in northeastern Arizona, northwestern New Mexico, and parts of southern Utah. This work had as its specific objective the establishing of correlations of Permian rocks in the Zuni uplift, Defiance uplift, and Monument Valley upwarp. The determination of these relations, it is believed, will be of aid in the current activities of the Geological Survey in the Navajo Reservation which have as objectives the investigation of the mineral fuels and water resources of the area.
Date: 1961
Creator: Read, C. B. & Wanek, Alexander A.
Partner: UNT Libraries Government Documents Department

The Upper Cretaceous Ammonite Genus Barroisiceras in the United States

Description: From introduction: The ammonite genus Barroisiceras Grossouvre is noteworthy because of its wide geographic distribution and its apparently small stratigraphic range. It is reported from deposits of Coniacian age in Europe, Africa, South America, and North America. In the North American Upper Cretaceous it is rather rare, authentic species having been recognized hitherto only in the Austin chalk of Texas, in the Coniacian beds of Zumpango del Rio, Guerrero, Mexico, and, with doubt as to the source, in New Jersey. The Texan species, B. dentatocarinatum (Roemer), is by no means an abundant form, though among those described in early work in the region. The Mexican representatives of the genus thus far described include only fragmentary specimens not specifically named. The occurrence ascribed to New Jersey is based on a fragment that seems to belong to Barroisiceras but whose source is very doubtful.
Date: 1931
Creator: Reeside, John B., Jr.
Partner: UNT Libraries Government Documents Department

Shorter Contributions to General Geology, 1929

Description: From introduction: This report describes the deposits of analcite in the Green River formation, to compare them with other similar deposits, and to present them with other similar deposits, and to present the observations and inferences that led him to explain them as alteration products of volcanic ash that fell into an ancient saline lake. The report also records the occurrence of several thin beds of sepiolite, or meerschaum, in the Green River formation and presents new data on the molds of saline minerals of the Green River formation whose determination affects directly the interpretation of the analcite and sepiolite deposits.
Date: 1930
Creator: Mendenhall, W. C.
Partner: UNT Libraries Government Documents Department