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Publications

Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center

Filter Total Items: 2337

Petrographic and chemical characteristics of pyrite-marcasite mineralization in hole 465A, southern Hess Rise

Core recovered from Hess Rise contains concentrations of pyrite, marcasite, and barite in the lowermost meter of limestone (Unit II) and in the brecciated upper part of the underlying volcanic basement (Unit HI). Petrographic and chemical data indicate that the sulfide-barite assemblage in the limestone is mainly a product of low-temperature diagenetic processes. The iron-sulfide phases are biogen
Authors
Randolph A. Koski, James R. Hein

Reconnaissance geologic map of the Topaz Lake 15 minute quadrangle, California and Nevada, with Quaternary geology

No abstract available.
Authors
David John, James Giusso, W. J. Moore, R. A. Armin, J. C. Dohrenwend

Two examples of seismic zonation in the San Francisco Bay region

The science of earthquakes in complex, requiring data and research in seismology, geology, soil mechanics, geophysics, hydrology, and engineering. Nevertheless, if earthquake hazards are to be reduced, earth science information must be translated from scientific and technical language into a form that can be effectively used by planners and decisionmakers. Out of the need to use earth science info
Authors
W. J. Kockelman, E. E. Brabb

Physical factors that could restrict mineral supply

Stages in the metal supply process are affected by each of the following physical (geologic) factors: (1) geographic distribution of concentrations of potential ore minerals, (2) depth of these concentrations, (3) mineralogy, (4) grain size of the minerals, and (5) grade and (6) tonnages of the concentrations. For mineral deposits of each type in each geologic and political environment, the lowest
Authors
John H. DeYoung, Donald A. Singer

Magnetic effects of maghemitization of oceanic crust

Both theoretical considerations and available experimental results indicate that magnetic effects of maghemitization are strongly dependent on the grain size of the originally unoxidized titanomagnetite. Maghemitization of single‐domain titanomagnetite results in a decrease in coercivity, an increase in susceptibility, and a large decrease in Q ratio. Maghemitization of multidomain titanomagnetite
Authors
M. Prevot, A. Lecaille, Edward A. Mankinen

Research in the Geysers-Clear Lake geothermal area, Northern California

The Geysers-Clear Lake area is one of two places in the world where major vapor-dominated hydrothermal reservoirs are commercially exploited for electric power production. Because energy can be extracted more efficiently from steam than from hot water, vapor-dominated systems are preferable for electric power generation, although most geothermal electric power facilities tap water-dominated system

Geologic mapping of Kentucky: A history and evaluation of the Kentucky Geological Survey--U.S. Geological Survey Mapping Program, 1960-1978

In 1960, the U.S. Geological Survey and the Kentucky Geological Survey began a program to map the State geologically at a scale of 1:24,000 and to publish the maps as 707 U.S. Geological Survey Geologic Quadrangle Maps. Fieldwork was completed by the spring of 1977, and all maps were published by December 1978. Geologic mapping of the State was proposed by the Kentucky Society of Professional
Authors
Earle Rupert Cressman, Martin C. Noger

Drake Peak — A structurally complex rhyolite center in southeastern Oregon

The Drake Peak volcanic center of middle Miocene age, located about 25 km northeast of Lakeview, Oreg., is a structurally complex eruptive center that resulted from several episodes of intrusion and extrusion of rhyolite. Two thousand meters of andesite and basalt flows, lahars, and volcaniclastic rocks of late Eocene age, and of basaltic andesite, tuff, and flood basalts of Eocene to middle Mioce
Authors
Ray Wells