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B. C. Moring

Publications and source records attributed to B. C. Moring.

13 recordsLinked to original sources
USGS2006

Geologic map of the San Francisco Bay region

The rocks and fossils of the San Francisco Bay region reveal that the geology there is the product of millions of years at the active western margin of North America. The result of this history is a complex mosaic of geologic materials and structures that form the landscape. A geologic map is one of the basic tools to understand the geology, geologic hazards, and geologic history of a region. With heightened public awareness about earthquake hazards leading up to the 100th anniversary of the 1906 San Francisco earthquake, the U.S. Geological Survey (USGS) is releasing new maps of the San Francisco Bay Area designed to give residents and others a new look at the geologic history and hazards of the region. The “Geologic Map of the San Francisco Bay region” shows the distribution of geologic materials and structures, demonstrates how geologists study the age and origin of the rocks and deposits that we live on, and reveals the complicated geologic history that has led to the landscape that shapes the Bay Area.

California↗
USGS1990

Map showing drill-hole depths, lithologic intercepts, and partial isopachs of basin fill in the Winnemucca 1 degree by 2 degrees quadrangle, Nevada

The purpose of this map is to aid in the mineral-resource assessment and exploration of covered host rocks by displaying and interpreting data that can be used to estimate the depth of basin fill in the Winnemucca 1° by 2° quadrangle, Nevada. Publicly available information used in making this map includes water, petroleum, and geothermal well data, gravity data and models, seismic profiles, and geologic and geomorphic reports. Wells logs used for this map of the Winnemucca quadrangle are from the following sources: (1) logs of more than 1,000 water wells reported to the State of Nevada Division of Water Resources, which are on file with them in Reno and at the with U.S. Geological Survey in Carson City, (2) 44 petroleum wells collected by the Nevada Bureau of Mines (Lintz, 1957; Schilling and Garside, 1968; Garside and Schilling, 1977, Garside and others, 1977; 1988), and (3) Two geothermal wells reported in Zoback (1979) and Flynn and others (1982). Data from isostatic residual and Bouguer gravity maps by Wagini (1985) contributed to the interpretation of basin configuration. Gravity models of Dixie Valley (Schaefer, 1982, and Speed, 1976) and Grass Valley (Grannell and Noble, 1977) and seismic profiles of Grass and Pine Valleys (Potter and others, 1987) helped refine basis interpretations in those areas. The geologic base map of Paleozoic and Mesozoic igneous and sedimentary rocks, Tertiary volcanic and sedimentary rocks, and Cenozoic structures was simplified from Stewart and Carlson (1976b).

Nevada↗
USGS1986

Platinum-group element resources in podiform chromitites from California and Oregon

Rock samples from about 280 podiform chromite deposits in California and Oregon were analyzed for Pt, Pd, Rh, and Ir by fire assay-atomic absorption and spectrographic techniques to estimate by-product platinum-group element potential of chromite mining. These deposits include ophiolites from the Sierra Nevada, Klamath Mountains, Coast Ranges, and the Canyon Mountain Complex; the deposits vary from Paleozoic to Mesozoic age and vary in size, shape, texture, and degree of metamorphism. The maximum platinum-group element contents (in ppm) measured for chromitites are: Pt, 2.53; Pd, 0.2; Rh, 0.14; Ru, 4.93; and Ir, 2.93.Correlations between Pt and Rh (0.60), Rh and Ir (0.64), Rh and Ru (0.71), and Ir and Ru (0.85) are significant at the 1 percent level. Relatively small but significant differences in platinum-group element content exist between geologic terranes. Chromite production from California and Oregon amounts to about 692,000 metric tons (1914-1985); the mean contained platinum-group element amounts in troy ounces are: Pt, 850; Pd, 100; Rh, 260; Ru, 4200; and Ir, 1,700, using estimated grades. Previous investigators have suggested that relatively few samples can represent the platinum-group element content of a podiform chromite deposit; therefore, these analyses are assumed to approximate "grades." Total world resources of platinum-group elements in podiform chromite deposits are estimated in troy ounces to be: Pt, 210,000; Pd, 25,000; Rh, 64,000; Ru, 1,000,000; and Ir, 420,000.

Economic Geology↗