Publications
Filter Total Items: 1147
Geometry, structure, and concealed lithology of the San Rafael Basin, southeastern Arizona
The contiguous United States has been well explored for exposed conventional mineral deposits. Therefore, it is likely that many economically viable and strategically significant conventional undiscovered mineral deposits will be found in bedrock concealed beneath basin sediments. Mineral resource assessments must incorporate an understanding of the geometry, structure, and concealed lithology of
Authors
Mark W. Bultman
Preliminary geologic map of the San Jose 30 X 60-minute quadrangle, California: A digital database
No abstract available.
Authors
Carl M. Wentworth, M. Clark Blake, Robert J. McLaughlin, Russell W. Graymer
Inversion of gravity data to define the pre-Tertiary surface and regional structures possibly influencing ground-water flow in the Pahute Mesa-Oasis Valley region, Nye County, Nevada
A three-dimensional inversion of gravity data from the Pahute Mesa–Oasis Valley region reveals a topographically complex pre-Tertiary basement surface. Beneath Pahute Mesa, the thickness of the Tertiary volcanic deposits may exceed 5 km within the Silent Canyon caldera complex. South of Pahute Mesa in Oasis Valley, basement is shallower (< 1 km) but between this valley and the Timber Mountain cald
Authors
T. G. Hildenbrand, V. E. Langenheim, E. A. Mankinen, E. H. McKee
Geologic framework for the Puget Sound aquifer system, Washington and British Columbia
The Puget-Willamette study area is composed of two distinct subareas, the Puget Sound Lowland and the Willamette Lowland. The study area for this report is the Puget Sound Lowland, which is located in western Washington and in a small part of southwestern British Columbia, Canada. The lowland encompasses an area of about 17,610 square miles and contains about 2,615 square miles of saltwater. The u
Authors
M. A. Jones
Structure and metamorphism of the Franciscan Complex, Mt. Hamilton area, Northern California
Truncation of metamorphic isograds and fold axes within coherent terranes of Franciscan metagraywacke by intervening zones of melange indicate that the melange is tectonic and formed after the subduction-related metamorphism and folding. These relations are expressed in two terranes of blueschist-facies rocks of the Franciscan Complex in the Mt. Hamilton area, northern California-the Jurassic Yoll
Authors
M. C. Blake, C. M. Wentworth
Foreshocks and aftershocks of the great 1857 California earthquake
The San Andreas fault is the longest fault in California and one of the longest strike-slip faults anywhere in the world, yet we know little about many aspects of its behavior before, during, and after large earthquakes. We conducted a study to locate and to estimate magnitudes for the largest foreshocks and aftershocks of the 1857 M 7.9 Fort Tejon earthquake on the central and southern segments o
Authors
A.J. Meltzner, D. J. Wald
How useful is landslide hazard information? Lessons learned in the San Francisco Bay region
Landslides, worldwide and in the United States, are arguably the most costly natural hazard. Substantial landslide information is available, but much of it remains underutilized, as a disconnect exists among geologists, decision makers, and the public. The lack of a national landslide insurance policy exacerbates this situation and promotes litigation as the principal recourse for recouping landsl
Authors
D. G. Howell, D.W. Ramsey, E. E. Brabb
Geology and regional correlation of the Cretaceous and Paleogene rocks of the Gualala block, northern California
No abstract available.
Authors
C. M. Wentworth, D. L. Jones, E. E. Brabb
Character of the middle Nonlithophysal Zone of the Topopah Spring Tuff at Yucca Mountain
No abstract available.
Authors
David C. Buesch, R.W. Spengler
Detailed correlation of lithostratigraphic and borehole geophysical log data for identifying contacts at Yucca Mountain
No abstract available.
Authors
David C. Buesch, R.W. Spengler
A simplified economic filter for open-pit gold-silver mining in the United States
In resource assessments of undiscovered mineral deposits and in the early stages of exploration, including planning, a need for prefeasibility cost models exists. In exploration, these models to filter economic from uneconomic deposits help to focus on targets that can really benefit the exploration enterprise. In resource assessment, these models can be used to eliminate deposits that would proba
Authors
Donald A. Singer, W. David Menzie, Keith R. Long
Geology of the onshore part of San Mateo County, California: A digital database
No abstract available.
Authors
E. E. Brabb, R. W. Graymer, D. L. Jones