Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2354
Geochemistry of selected mercury mine-tailings in the Parkfield Mercury District, California
The Parkfield mercury district is located in the southern part of the California Coast Range mercury mineral belt and contains three silica-carbonate-type mercury deposits that have had significant mercury production. Mercury was first produced in the district in 1873, but the main period of production occurred from 1915-1922. Total production from the district is about 5,000 flasks of mercury (a
Authors
James J. Rytuba, Boris B. Kotlyar, Gregg Wilkerson, Jerry Olson
Relationship of faults in basin sediments to the gravity and magnetic expression of their underlying fault systems
Gravity and magnetic surveys were performed along the western flanks of the Santa Rita Mountain range located in southeastern Arizona to develop an understanding of the relationship between surface fault scarps within the basin fill sediments and theirgeophysical response of the faults at depth within the bedrock. Data were acquired for three profiles, one of them along the northern terrace of Mon
Authors
Christopher A. Baldyga
Geologic map of the Tucson and Nogales quadrangles (Arizona, scale 1:250,000): A digital database
The geologic map of the Tucson-Nogales 1:250,000 scale quadrangle (Peterson and others, 1990) was digitized by U.S. Geological Survey staff and University of Arizona contractors at the Southwest Field Office, Tucson, Arizona, in 2000 for input into a geographic information system (GIS). The database was created for use as a basemap in a decision support system designed by the National Industrial M
Authors
J.A. Peterson, J. R. Berquist, S. J. Reynolds, S. S. Page-Nedell, Gustav P. Oland, Douglas M. Hirschberg
Apatite fission-track evidence of widespread Eocene heating and exhumation in the Yukon-Tanana Upland, interior Alaska
We present an apatite fission-track (AFT) study of five plutonic rocks and seven metamorphic rocks across 310 km of the YukonTanana Upland in east-central Alaska. Samples yielding ~40 Ma AFT ages and mean confined track lengths > 14 µm with low standard deviations cooled rapidly from >120°C to <50°C during a 35 Ma period, beginning at about 40 Ma. Data from samples yielding AFT ages >40 Ma sugge
Authors
Cynthia Dusel-Bacon, J.M. Murphy
Significance of geologic and biostratigraphic relations between the overlap assemblage and Havallah sequence, southern Shoshone Range, Nevada
No abstract available.
Authors
Thomas E. Moore, B. L. Murchey, A. G. Harris
The demise of the San Bruno Fault
No abstract available.
Authors
Manuel G. Bonilla, R.C. Jachens, A. S. Jayko, C. M. Wentworth, Arthur F. McGarr
Publications of the Western Earth Surface Processes Team, 1999
The Western Earth Surfaces Processes Team (WESPT) of the U.S. Geological Survey, Geologic Division (USGS, GD), conducts geologic mapping and related topical earth- science studies in the western United States. This work is focused on areas where modern geologic maps and associated earth-science data are needed to address key societal and environmental issues such as ground-water quality, potential
Authors
Paul Stone, Charles L. Powell
Preliminary potential-field constraints on the geometry of the San Fernando basin, Southern California
Gravity and magnetic data provide new insights on the structural underpinnings of the San Fernando Basin region, which may be important to ground motion models. Gravity data indicate that a deep basin (>5 km) underlies the northern part of the San Fernando Valley; this deep basin is required to explain the lowest gravity values over the Mission Hills thrust fault. Gravity modeling, constrained by
Authors
Victoria E. Langenheim, Andrew Griscom, R.C. Jachens, T. G. Hildenbrand
Locations and ages of middle Tertiary volcanic centers in coastal California
This report includes a map and three tables that summarize available information on the locations and ages of late Oligocene to middle Miocene volcanic centers in coastal California. This information, in turn, provides supporting documentation for a planned formal publication by D.S. Wilson, P.A. McCrory, and R.G. Stanley on the implications of volcanism in coastal California for the tectonic hist
Authors
Richard G. Stanley, Douglas S. Wilson, Patricia A. McCrory
Minerals in our environment
Minerals are found everywhere in our daily lives. This poster depicts numerous items found throughout a home, and the mineral(s) or mineral resources used in the ingredients of, or construction/manufacturing of those items. Designed for K-8 Teachers this poster can be scaled and is printable at 36" x 60" and legible at 11" x 17" in size.
Authors
Judy Weathers, John Galloway, Dave Frank
Field estimates of gravity terrain corrections and Y2K-compatible method to convert from gravity readings with multiple base stations to tide- and long-term drift-corrected observations
Gravity observations are directly made or are obtained from other sources by the U.S. Geological Survey in order to prepare maps of the anomalous gravity field and consequently to interpret the subsurface distribution of rock densities and associated lithologic or geologic units. Observations are made in the field with gravity meters at new locations and at reoccupations of previously established
Authors
Donald Plouff
Preliminary model of the pre-Tertiary basement rocks beneath Yucca Flat, Nevada Test Site, Nevada, based on analysis of gravity and magnetic data
The Environmental Restoration Program of the U.S. Department of Energy, Nevada Operations Office, was developed to investigate the possible consequences to the environment of 40 years of nuclear testing on the Nevada Test Site. The majority of the tests were detonated underground, introducing contaminants into the ground-water system (Laczniak and others, 1996). An understanding of the ground-wate
Authors
Geoffrey A. Phelps, Edwin H. McKee, D. Sweetkind, V. E. Langenheim