Publications
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Fractal lognormal percentage assessment of porphyry copper resources
No abstract available.
Authors
R. A. Crovelli, S. B. Suslick, Donald A. Singer, R.H. Balay
World class base and precious metal deposits; a quantitative analysis
Over 62 percent of the 193,000 metric tons of gold discovered to date is located in four countries and more than 68 percent occurs in four types of mineral deposits. About 55 percent of the 1,740,000 metric tons of silver found is in four countries and 45 percent is in four types of deposits. Fifty-six percent of the 1.52 billion metric tons of discovered copper is from four countries and four typ
Authors
Donald A. Singer
Biostratigraphic constraints on formation and timing of accretion in a subduction complex: An example from the Franciscan Complex of Northern California
The determination of the total age coverage of pelagic bedded chert is particularly important in studies of ancient accretionary complexes because the time span represents the minimum travel time of an oceanic plate before accretion at an island arc or continental margin. The Yolla Bolly terrane of the Franciscan Complex consists of rare metabasalt overlain by bedded radiolarian chert which in tur
Authors
Y. Isozaki, M. Clark Blake
Paleozoic ophiolitic assemblages within the southern New England orogen of eastern Australia: Implications for growth of the Gondwana margin
Several ophiolitic assemblages occur in the southern New England orogen. The development of these rocks and their relations to the rest of the orogen have major implications for the tectonic evolution of eastern Gondwana. A major, narrow but elongate belt of Early Cambrian suprasubduction zone ophiolite crops out along and near the PeelManning Fault System and is juxtaposed against younger arc and
Authors
J.C. Aitchinson, M. Clark Blake, P.G. Flood, A. S. Jayko
The Pennsylvanian Fire Clay tonstein of the Appalachian basin—Its distribution, biostratigraphy, and mineralogy
The Middle Pennsylvanian Fire Clay tonstein, mostly kaolinite and minor accessory minerals, is an altered and lithified volcanic ash preserved as a thin, isochronous layer associated with the Fire Clay coal bed. Seven samples of the tonstein, taken along a 300-km traverse of the central Appalachian basin, contain cogenetic phenocrysts and trapped silicate-melt inclusions of a rhyolitic magma. The
Authors
C. L. Rice, Harvey E. Belkin, T.W. Henry, R. E. Zartman, Michael J. Kunk
Preliminary geologic map of the Niles 7.5-minute Quadrangle, Alameda County, California
No abstract available.
Authors
R. W. Graymer, D. L. Jones, E. E. Brabb, E. J. Helley
Preliminary geologic map emphasizing bedrock formations in Contra Costa County, California: A digital database
No abstract available.
Authors
R. W. Graymer, David Lawrence Jones, Earl E. Brabb
Geologic studies in Alaska by the U.S. Geological Survey, 1993
This collection of 19 papers continues the annual series of U.S. Geological Survey reports on geologic investigations in Alaska. Contributions include 14 Articles and 5 shorter Geologic Notes that report results from all corners of the State.USGS activities in Alaska cover a broad spectrum of earth science topics, including the environment, hazards, resources, and geologic framework studies. Three
Bibliography of The World Energy Resources Program
The following publications were prepared in the course of World Energy Studies by program scientists. Most are open-file reports because we consider it our prime responsibility to get the program supporting data into the public record. Various of the authors have also seen fit to publish their work in refereed scientific journals and those publication outlets are also listed.The summation of the p
Authors
Charles D. Masters
Integrated geology and preliminary cross section along the north ramp of the Exploratory Studies Facility, Yucca Mountain
The Exploratory Studies Facility is a major part of the site characterization activities at Yucca Mountain, Nevada, and the north ramp is the first phase of construction. The N61W trending north ramp will transect the Bow Ridge and Drill Hole Wash faults and numerous minor faults, and traverses two thick welded tuffs and several nonwelded tuff units. A preliminary cross section along the north ram
Authors
D.C. Buesch, R. P. Dickerson, R.M. Drake, R.W. Spengler
Regional porosity trends of the Upper Jurassic Norphlet Formation in southwestern Alabama and vicinity, with comparisons to formations of other basins
Sandstone porosity of the Upper Jurassic Norphlet Formation in southwestern Alabama and vicinity decreases systematically as depth and thermal maturity increase over a wide range. Median porosity is about 25% where equivalent vitrinite reflectance (Ro) is slightly over 0.7% in the northern part of the study area (Clarke County, Mississippi). Median porosity is reduced to 8% where Ro approaches 2.7
Authors
James W. Schmoker, Christopher J. Schenk
Continent-ocean transition in Alaska: The tectonic assembly of eastern Denalia
Alaska is the eastern, subaerial part of a large subcontinent of distinctive tectonic character that serves as an isthmus between nuclear North America, with its fringing belt of allochthonous terranes, and the accreted terranes and volcanic belts that constitute northeastern Russia. Physiographically, this subcontinent, which we name Denalia, is a bulge in the continental platform in the vicinity
Authors
Thomas E. Moore, Arthur Grantz, S. M. Roeske