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Eolian sand bodies of the world
E. D. McKee
1983, Developments in Sedimentology (38) 1-25
This chapter examines the eolian sand bodies of the world. Analyses regarding grain size and sorting distribution at Great Sand Dunes indicate that the higher dunes contain much more fine-grained sand and much less medium-grained sand than do the lower dunes, and, in addition, they are definitely better sorted. Cross-stratification...
Water resources data: Oregon
Water Resources Division, U.S. Geological Survey
1983, Report, U.S. Geological Survey water-supply paper
No abstract available....
Water resources data: Oklahoma
Water Resources Division, U.S. Geological Survey
1983, Report, U.S. Geological Survey water-supply paper
No abstract available....
A tale of two plutons: petrographic and mineralogic constraints on the petrogenesis of the Red Lake and Eagle Peak plutons, central Sierra Nevada, California
J.H. Noyes, D. R. Wones, F.A. Frey
1983, Journal of Geology (91) 353-379
The two plutons are similar in age (K/Ar, 87-89 m.y.) and range in composition from granodiorite to granite. The Red Lake pluton is equigranular, has a locally greisened marginal zone, and shows only minor mineralogical and chemical zoning, whereas the Eagle Peak pluton is mineralogically, compositionally and texturally zoned, with...
Hydrologic and geomorphic studies of the Platte River basin
Water Resources Division, U.S. Geological Survey
1983, Professional Paper 1277
The channels of the Platte River and its major tributaries, the South Platte and North Platte Rivers in Colorado, Wyoming, and Nebraska, have undergone major changes in hydrologic regime and morphology since about 1860, when the water resources of the basin began to be developed for agricultural, municipal, and industrial...
DIGITAL GEOLOGIC MAP OF THE UNITED STATES.
Patricia Fulton
1983, Conference Paper, Technical Papers of the American Congress of Surveying and Mapping
The geologic map of the United States was published in 1974 by the U. S. Geological Survey. This major publication contains an enormous amount of information on the surficial geology of the United States. Many geologists have used this map as a research tool. Most have needed information from only...
Ultrastructural changes in the hepatocytes of juvenile rainbow trout and mature brown trout exposed to copper or zinc
H.V. Leland
1983, Environmental Toxicology and Chemistry (2) 353-368
Morphological changes in hepatocytes of mature brown trout (Salmo trutta Linnaeus) and juvenile rainbow trout (Salmo gairdneri Richardson), accompanying chronic exposures to copper and zinc, were examined by transmission electron microscopy. At a concentration of copper not inhibitory to the final stages of gonadal development or spawning of brown trout,...
Geobarometry of ultramafic xenoliths from Loihi Seamount, Hawaii, on the basis of CO2 inclusions in olivine
E. Roedder
1983, Earth and Planetary Science Letters (66) 369-379
Abundant fluid inclusions in olivine of dunite xenoliths (∼1–3 cm) in basalt dredged from the young Loihi Seamount, 30 km southeast of Hawaii, are evidence for three coexisting immiscible fluid phases—silicate melt (now glass), sulfide melt (now solid), and dense supercritical CO2 (now liquid + gas)—during growth and later fracturing of some of...
Selective concentration of cesium in analcime during hydrothermal alteration, Yellowstone National Park, Wyoming
T. E. C. Keith, J. M. Thompson, R. E. Mays
1983, Geochimica et Cosmochimica Acta (47) 795-804
Chemical and mineralogical studies of fresh and hydrothermally altered rhyolitic material in Upper and Lower Geyser Basins, Yellowstone National Park, show that all the altered rocks are enriched in Cs and that Cs is selectively concentrated in analcime. The Cs content of unaltered rhyolite lava flows, including those from which...
Seismicity at Fuego, Pacaya, Izalco, and San Cristobal Volcanoes, Central America, 1973-1974
S.R. McNutt, D.H. Harlow
1983, Bulletin Volcanologique (46) 283-297
Seismic data collected at four volcanoes in Central America during 1973 and 1974 indicate three sources of seismicity: regional earthquakes with hypocentral distances greater than 80 km, earthquakes within 40 km of each volcano, and seismic activity originating at the volcanoes due to eruptive processes. Regional earthquakes generated by the...
Rare-earth element geochemistry and the origin of andesites and basalts of the Taupo Volcanic Zone, New Zealand
J. W. Cole, K. V. Cashman, P.C. Rankin
1983, Chemical Geology (38) 255-274
Two types of basalt (a high-Al basalt associated with the rhyolitic centres north of Taupo and a "low-Al" basalt erupted from Red Crater, Tongariro Volcanic Centre) and five types of andesite (labradorite andesite, labradorite-pyroxene andesite, hornblende andesite, pyroxene low-Si andesite and olivine andesite/low-Si andesite) occur in the Taupo Volcanic Zone...
Incorporation of prior information on parameters into nonlinear regression groundwater flow models: 2. Applications
Richard L. Cooley
1983, Water Resources Research (19) 662-676
This paper investigates factors influencing the degree of improvement in estimates of parameters of a nonlinear regression groundwater flow model by incorporating prior information of unknown reliability. Consideration of expected behavior of the regression solutions and results of a hypothetical modeling problem lead to several general conclusions. First, if the...
Quaternary geology of the Rhode Island inner shelf
S. W. Needell, C. J. O’Hara, H.J. Knebel
1983, Marine Geology (53) 41-53
Five sedimentary units and three erosional unconformities identified in high-resolution seismic-reflection profiles reveal the stratigraphic framework and Quaternary history of the inner continental shelf south of Narragansett Bay, Rhode Island. Late Tertiary to early Pleistocene rivers eroded the pre-Mesozoic bedrock and the Upper Cretaceous to lower Tertiary coastal plain and...
Scoresum - A technique for displaying and evaluating multi-element geochemical information, with examples of its use in regional mineral assessment programs
M.A. Chaffee
1983, Journal of Geochemical Exploration (19) 361-381
A technique called SCORESUM was developed to display a maximum of multi-element geochemical information on a minimum number of maps for mineral assessment purposes. The technique can be done manually for a small analytical data set or can be done with a computer for a large data set. SCORESUM...
Conjunctive use of groundwater and surface water for irrigated agriculture: Risk aversion
John D. Bredehoeft, Richard A. Young
1983, Water Resources Research (19) 1111-1121
In examining the South Platte system in Colorado where surface water and groundwater are used conjunctively for irrigation, we find the actual installed well capacity is approximately sufficient to irrigate the entire area. This would appear to be an overinvestment in well capacity. In this paper we examine to what...
Analysis of spurious oscillation modes for the shallow water and Navier-Stokes equations
Roy A. Walters, G. F. Carey
1983, Computers and Fluids (11) 51-68
The origin and nature of spurious oscillation modes that appear in mixed finite element methods are examined. In particular, the shallow water equations are considered and a modal analysis for the one-dimensional problem is developed. From the resulting dispersion relations we find that the spurious modes in elevation are associated...
40Ar/39Ar and U-Th-Pb dating of separated clasts from the Abee E4 chondrite
D.D. Bogard, D.M. Unruh, M. Tatsumoto
1983, Earth and Planetary Science Letters (62) 132-146
Determinations of40Ar/39Ar and U-Th-Pb are reported for three clasts from the Abee (E4) enstatite chondrite, which has been the object of extensive consortium investigations. The clasts give40Ar/39Ar plateau ages and/or maximum ages of 4.5 Gy, whereas two of the clasts give...
Orickite and coyoteite, two new sulfide minerals from Coyote Peak, Humboldt County, California.
Richard C. Erd, G.K. Czamanske
1983, American Mineralogist (68) 245-254
Minute quantities of orickite and coyoteite occur with rare alkali iron sulphides in a mafic alkalic diatreme near Orick, Humboldt County. Orickite, NaxKyCu0.95Fe1.06zH2O (x,y < 0.03, z < 0.5), is hexagonal, a 3.695, c 6.16 A, D 4.212 g/cm3, Z = 4. The strongest XRD reflections are 3.08(100), 3.20(90), 2.84(60),...
Iron disulfide minerals and the genesis of roll-type uranium deposits
R. L. Reynolds, M. B. Goldhaber
1983, Economic Geology (78) 105-120
FeS 2 minerals in host rocks for deposits that contain fossil vegetal (organic) matter differ in abundance, distribution, texture, and sulfur isotopic ratios from FeS 2 minerals in host rocks for deposits that do not contain fossil vegetal matter. In three South Texas deposits lacking such organic matter, preore FeS 2 is dominantly euhedral pyrite which...