Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2350
The Loma Prieta, California, earthquake of October 17, 1989: Aftershocks and postseismic effects
While the damaging effects of the earthquake represent a significant social setback and economic loss, the geophysical effects have produced a wealth of data that have provided important insights into the structure and mechanics of the San Andreas Fault system. Generally, the period after a large earthquake is vitally important to monitor. During this part of the seismic cycle, the primary fault a
Authors
Paul A. Reasenberg, Lynn D. Dietz, William L. Ellsworth, Robert W. Simpson, John W. Gephart, Susan Y. Schwartz, Glenn D. Nelson, H. Guo, A. Lerner-Lam, William Menke, Susan E. Hough, Leif Wennerberg, K.S. Breckenridge, Jeff Behr, Roger G. Bilham, Paul Bodin, Arthur G. Sylvester, Jon S. Galehouse, R. Burgmann, Paul Segall, Michael Lisowski, Jerry L. Svarc, John Langbein, M.F. Linker, J.R. Rice, M. T. Gladwin, R. L. Gwyther, R.H.G. Hart, Randall Mackie, Theodore R. Madden, Edward A. Nichols
Quaternary geology of Alameda County, and parts of Contra Costa, Santa Clara, San Mateo, San Francisco, Stanislaus, and San Joaquin Counties, California: A digital database
Alameda County is located at the northern end of the Diablo Range of Central California. It is bounded on the north by the south flank of Mount Diablo, one of the highest peaks in the Bay Area, reaching an elevation of 1173 meters (3,849 ft). San Francisco Bay forms the western boundary, the San Joaquin Valley borders it on the east and an arbitrary line from the Bay into the Diablo Range forms th
Authors
E. J. Helley, R. W. Graymer
Classification of mineral deposits into types using mineralogy with a probabilistic neural network
In order to determine whether it is desirable to quantify mineral-deposit models further, a test of the ability of a probabilistic neural network to classify deposits into types based on mineralogy was conducted. Presence or absence of ore and alteration mineralogy in well-typed deposits were used to train the network. To reduce the number of minerals considered, the analyzed data were restricted
Authors
Donald A. Singer, Ryoichi Kouda
Age and correlation of tephra layers, position of the Matuyama-Brunhes chron boundary, and effects of Bishop Ash eruption on Owens Lake, as determined from drill hole OL-92, Southeast California
Tephra layers in the ~323-m-deep Owens lake drill hole OL-92 correlate to tephra layers that have been identified and dated elsewhere in the western United States. Tephra layers identified are the Bishop ash bed (758 ka) at 309.2–298.6 m; the Dibekulewe (ash) bed (ca. 470 ka to ca. 610 ka) at ~224 m; and one of several ash beds in Walker Lake (ca. 60 ka to ca. 80 ka) at ~50.7 m. Other tephra layer
Authors
Andrei M. Sarna-Wojcicki, Charles E. Meyer, Elmira Wan
Mass balance approach to selenium cycling through the San Joaquin Valley, sources to river to bay
Surface and ground waters of the Central Valley of California (e.g., rivers, dams, off-stream storage reservoirs, pumping facilities, irrigation and drinking water supply canals, agricultural drainage canals) are part of a hydrologic system that makes up a complex ecosystem extending from the riparian wetlands of the Sacramento and San Joaquin Rivers through the San Francisco Bay/Delta Estuary to
Authors
Theresa S. Presser, David Z. Piper
Seasonal variation in metal concentrations in a stream affected by acid mine drainage, St. Kevin Gulch, Colorado
Mining of mineral deposits in the Rocky Mountains has left a legacy of acidic inflows to otherwise pristine upland watersheds. Since 1986, the U.S. Geological Survey has studied physical, chemical, and biological processes that affect the transport and transformation of metals in St. Kevin Gulch, an acidic, metal-rich stream near Leadville, Colorado. Well-known chemical processes have been quantif
Authors
B. A. Kimball
Coseismic deformation during the 1989 Loma Prieta earthquake and range-front thrusting along the southwestern margin of the Santa Clara Valley, California
Damage patterns caused by the 1989 Loma Prieta earthquake along the southwestern margin of the Santa Clara Valley, California, form three zones that coincide with mapped and inferred traces of range-front thrust faults northeast of the San Andreas fault. Damage in these zones was largely contractional, consistent with past displacement associated with these faults. The damage zones coincide with g
Authors
V. E. Langenheim, K. M. Schmidt, R.C. Jachens
Use of a neural network to integrate geoscience information in the classification of mineral deposits and occurrences
No abstract available.
Authors
Donald A. Singer, Ryoichi Kouda
Preliminary geologic map of the Santa Susana 7.5' quadrangle, southern California: A digital database
This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report.
This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age
Authors
R.F. Yerkes, R. H. Campbell
Preliminary geologic map of the Moorpark 7.5' quadrangle, Southern California: A digital database
This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report.
This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age
Authors
R.F. Yerkes, R. H. Campbell
Preliminary geologic map of the Malibu Beach 7.5' quadrangle, Southern California: A digital database
This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report.
This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age
Authors
R.F. Yerkes, R. H. Campbell
Field guide for a GEOMAR & University of Kiel trip across the accreted terranes of the southern Klamath Mountains, California, June 14, 1997
No abstract available.
Authors
W. P. Irwin