Publications
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Recurrence interval and event age data for Type A faults Recurrence interval and event age data for Type A faults
This appendix summarizes available recurrence interval, event age, and timing of most recent event data for Type A faults considered in the Earthquake Rate Model 2 (ERM 2) and used in the ERM 2 Appendix C analysis as well as Appendix N (time-dependent probabilities). These data have been compiled into an Excel workbook named Appendix B A-fault event ages_recurrence_V5.0 (herein referred...
Authors
Timothy E. Dawson, Ray J. Weldon, Glenn P. Biasi
Spatial seismicity rates and maximum magnitudes for background earthquakes Spatial seismicity rates and maximum magnitudes for background earthquakes
The background seismicity model is included to account for M 5.0 - 6.5 earthquakes on faults and for random M 5.0 ? 7.0 earthquakes that do not occur on faults included in the model (as in earlier models of Frankel et al., 1996, 2002 and Petersen et al., 1996). We include four different classes of earthquake sources in the California background seismicity model: (1) gridded (smoothed)...
Authors
Mark D. Petersen, Charles S. Mueller, Arthur D. Frankel, Yuehua Zeng
Summary of geologic data and development of A Priori Rupture Models for the Elsinore, San Jacinto, and Garlock faults Summary of geologic data and development of A Priori Rupture Models for the Elsinore, San Jacinto, and Garlock faults
This appendix to the WGCEP Earthquake Rate Model 2 summarizes geologic data and documents the development of the rupture models for the Elsinore, San Jacinto, and Garlock faults. For the summary of available geologic data, the documentation is organized by fault and fault segment and includes a summary of slip rates, event timing and recurrence, slip-per-event, and historical seismicity...
Authors
Timothy E. Dawson, Tom K. Rockwell, Ray J. Weldon, Chris J. Wills
Development of final a-fault rupture models for WGCEP/ NSHMP Earthquake Rate Model 2 Development of final a-fault rupture models for WGCEP/ NSHMP Earthquake Rate Model 2
This appendix discusses how we compute the magnitude and rate of earthquake ruptures for the seven Type-A faults (Elsinore, Garlock, San Jacinto, S. San Andreas, N. San Andreas, Hayward-Rodgers Creek, and Calaveras) in the WGCEP/NSHMP Earthquake Rate Model 2 (referred to as ERM 2. hereafter). By definition, Type-A faults are those that have relatively abundant paleoseismic information (e...
Authors
Edward H. Field, Ray J. Weldon, Thomas Parsons, Chris J. Wills, Timothy E. Dawson, Ross S. Stein, Mark D. Petersen
California fault parameters for the National Seismic Hazard Maps and Working Group on California Earthquake Probabilities 2007 California fault parameters for the National Seismic Hazard Maps and Working Group on California Earthquake Probabilities 2007
This report describes development of fault parameters for the 2007 update of the National Seismic Hazard Maps and the Working Group on California Earthquake Probabilities (WGCEP, 2007). These reference parameters are contained within a database intended to be a source of values for use by scientists interested in producing either seismic hazard or deformation models to better understand...
Authors
Chris J. Wills, Ray J. Weldon, W. A. Bryant
Calculating California seismicity rates Calculating California seismicity rates
Empirically the rate of earthquakes = magnitude M is well fit by the Gutenberg-Richter relationship, logN=a-bM (1) where N is the number of earthquakes = M over a given time period, a is the number of M = 0 earthquakes over the same period, and b is a parameter that determines the ratio of larger to smaller earthquakes (Ishimoto and Iida 1939; Gutenberg and Richter 1944). Thus to...
Authors
Karen R. Felzer
WGCEP historical California earthquake catalog WGCEP historical California earthquake catalog
This appendix provides an earthquake catalog for California and the surrounding area. Our goal is to provide a listing for all known M > 5.5 earthquakes that occurred from 1850-1932 and all known M > 4.0 earthquakes that occurred from 1932-2006 within the region of 31.0 to 43.0 degrees North and -126.0 to -114.0 degrees West. Some pre-1932 earthquakes 4 M 5.5 are also listed. The...
Authors
Karen R. Felzer, Tianqing Cao
Modified Mercalli Intensity Maps for the 1868 Hayward Earthquake Plotted in ShakeMap Format Modified Mercalli Intensity Maps for the 1868 Hayward Earthquake Plotted in ShakeMap Format
To construct the Modified Mercalli Intensity (MMI) ShakeMap for the 1868 Hayward earthquake, we started with two sets of damage descriptions and felt reports. The first set of 100 sites was compiled by A.A. Bullock in the Lawson (1908) report on the 1906 San Francisco earthquake. The second set of 45 sites was compiled by Toppozada et al. (1981) from an extensive search of newspaper...
Authors
John Boatwright, Howard Bundock
The Uniform California Earthquake Rupture Forecast, version 2 (UCERF 2) The Uniform California Earthquake Rupture Forecast, version 2 (UCERF 2)
California?s 35 million people live among some of the most active earthquake faults in the United States. Public safety demands credible assessments of the earthquake hazard to maintain appropriate building codes for safe construction and earthquake insurance for loss protection. Seismic hazard analysis begins with an earthquake rupture forecast?a model of probabilities that earthquakes...
Authors
Major and EDXRF Trace Element Chemical Analyses of Volcanic Rocks from Lassen Volcanic National Park and Vicinity, California Major and EDXRF Trace Element Chemical Analyses of Volcanic Rocks from Lassen Volcanic National Park and Vicinity, California
This open-file report presents WDXRF major-element chemical data for late Pliocene to Holocene volcanic rocks collected from Lassen Volcanic National Park and vicinity, California. Data for Rb, Sr, Ba, Y, Zr, Nb, Ni, Cr, Zn and Cu obtained by EDXRF are included for many samples. Data are presented in an EXCEL spreadsheet and are keyed to rock units as displayed on the Geologic Map of...
Authors
Michael A. Clynne, L.J.P. Muffler, D. F. Siems, J.E. Taggart, Peggy Bruggman
The Hayward Fault— Is it due for a repeat of the powerful 1868 earthquake? The Hayward Fault— Is it due for a repeat of the powerful 1868 earthquake?
On October 21, 1868, a magnitude 6.8 earthquake struck the San Francisco Bay region. Although the region was then sparsely populated, this quake on the Hayward Fault was one of the most destructive in California's history. Recent studies show that such powerful Hayward Fault quakes have repeatedly jolted the region in the past. U.S. Geological Survey (USGS) scientists describe this fault...
Authors
Thomas M. Brocher, Jack Boatwright, James J. Lienkaemper, Carol S. Prentice, David P. Schwartz, Howard Bundock
Publications of the Volcano Hazards Program 2006 Publications of the Volcano Hazards Program 2006
The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity as funded by Congressional appropriation. Investigations are carried out in the Geology and Hydrology Disciplines of the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of Alaska Fairbanks Geophysical Institute...
Authors
Manuel Nathenson