Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2354
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
Modelling removal mechanisms of Pb, Cu, Zn and Cd in acidic groundwater during the neutralization by ambient surface and ground waters
Removal of Pb, Cu, Zn, and Cd during neutralization of acid rock drainage is examined using model simulations of field conditions and laboratory experiments involving mixing of natural drainage and surface waters or groundwaters. The simulations consider sorption onto hydrous Fe and Al oxides and particulate organic carbon, mineral precipitation, and organic and inorganic solution complexation of
Authors
Anthony J. Paulson, Laurie S. Balistrieri
Neogene contraction between the San Andreas fault and the Santa Clara Valley, San Francisco Bay region, California
In the southern San Francisco Bay region of California, oblique dextral reverse faults that verge northeastward from the San Andreas fault experienced triggered slip during the 1989 M7.1 Loma Prieta earthquake. The role of these range-front thrusts in the evolution of the San Andreas fault system and the future seismic hazard that they may pose to the urban Santa Clara Valley are poorly understood
Authors
Robert J. McLaughlin, V. E. Langenheim, K. M. Schmidt, R.C. Jachens, R. G. Stanley, A. S. Jayko, K. A. McDougall, J. C. Tinsley, Z. C. Valin
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
Suppression of large earthquakes by stress shadows: A comparison of Coulomb and rate-and-state failure
Stress shadows generated by California's two most recent great earthquakes (1857 Fort Tejon and 1906 San Francisco) substantially modified 19th and 20th century earthquake history in the Los Angeles basin and in the San Francisco Bay area. Simple Coulomb failure calculations, which assume that earthquakes can be modeled as static dislocations in an elastic half-space, have done quite well at appro
Authors
Ruth A. Harris, Robert W. Simpson
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