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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

Some American Jurassic Ammonites of the Genera Quenstedticeras, Cardioceras, and Amoeboceras, Family Cardioceratidae

Description: Introduction: The interpretation of the data furnished by the study of these fossils has been hindered somewhat because the exact stratigraphic location of much of the material is unknown. It was gathered with regard merely for the general stratigraphic and geographic position. However, as a knowledge of the general relationship forms to those of other areas is in itself of value to the stratigrapher and systematist it has seemed desirable to describe and figure the species.
Date: 1919
Creator: Reeside, John B., Jr.

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

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.

Shorter Contributions to General Geology, 1928

Description: From introduction: The district discussed in this report embraces the entire northern peninsula of Michigan and the parts of northern Wisconsin and northeastern Minnesota that were covered by a re-advance of the Superior lobe of the Labrador ice sheet late in the Wisconsin stage of glaciation.
Date: 1929
Creator: Mendenhall, W. C.

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

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

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.