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R.W. Simpson

Publications and source records attributed to R.W. Simpson.

At least 55 records · Page 3Linked to original sources
USGS1984

Aeromagnetic, Bouguer gravity, and interpretation maps of the Sheep Hole-Cadiz Wilderness Study Area (CDCA-305), San Bernardino County, California

The Federal Land Policy and Management Act (Public Law 94-579, October 21, 1976) requires the U.S. Geological Survey and the U.S. Bureau of Mines to conduct mineral surveys on certain areas to determine their mineral resource potential. Results must be made available to the public and be submitted to the President and the Congress. These maps presents the results of a mineral survey of the Sheep Hole-Cadiz Wilderness Study Area (CDCA-305), California Desert Conservation Area, San Bernardino County, California. The U.S. Bureau of Mines conducted a mineral survey of the Sheep Hole-Cadiz Wilderness Study Area, which encompasses approximately 200,000 acres including enclosed private lands, in south-central San Bernardino County, California. The U.S. Bureau of Mines studied the mineral resources of mines, prospects, and mineralized areas; geologic, geochemical, and geophysical investigations were conducted by the U.S. Geological Survey. The study area is located in the Mojave Desert 13 miles east of Amboy, California, 20 miles east of Twentynine Palms, California, and 90 miles east of San Bernardino, and encompasses parts of the Dale Lake, Bristol Lake, Cadiz Valley and Cadiz Lake 15-minute quadrangles. Its borders are defined by the Amboy Road and a gas pipeline service road on the northwest, the unimproved Cadiz Valley access road on the east, State Route 62 along the south, and the Iron Age mine road and an unimproved powerline service road on the west. Major access from the east and west is provided by State Route 62 and access from the north is provided by the Amboy Road. Companion reports to this one describe the mineral resource potential (March and others, 1982), the geology (Howard and John, 1984), and hydrothermal alteration studies (Raines, 1983).

California↗
USGS1983

AIRYROOT: A Fortran program for calculating the gravitational attraction of an Airy isostatic root out to 166.7 km

This report describes a FORTRAN-77 program called AIRYROOT which calculates the gravitational attraction at sea level of an Airy isostatic root extending out to a radius of 166.7 km. The program incorporates an efficient algorithm devised by Parker (1912) which uses the fast Fourier transform to calculate potential field anomalies. Input is a rectangular grid in a projected coordinate system which contains values describing topography (elevations and depths in meters) or surface load (mass in g/cm2). Output is a rectangular grid of values of the gravitational attraction of the root in milligals (mGal). A strategy is outlined for combining this output with published results describing the attraction of the root beyond 166.7 km, for upward continuing the total attraction to appropriate observation elevations, and for subtracting the result from Bouguer gravity data to produce an isostatic residual gravity map. This program can also be used to make complete Bouguer corrections to marine gravity data given appropriate bathymetric data sets.

Open-File Report↗
USGS1982

Digital colored residual and regional Bouguer gravity maps of the conterminous United States: Comments on significant features

The gravity maps were prepared from data obtained primarily from data files maintained by the Defense Mapping Agency of the Department of Defense and the Canadian Gravity Data Centre of the Earth Physics Branch of the Department of Energy, Mines, and Resources (Canada). The maps have been used in studies relating to earthquake/reactor hazards, geothermal energy, and nuclear repository site programs of the U.S. Geological Survey. Those shown here (250 km and 1000 km wavelength cut-off regional and residual gravity maps) are part of a series of digital gravity and terrain maps of the United States currently being developed by the authors.

Open-File Report↗