Publications
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The ShakeOut Scenario
This is the initial publication of the results of a cooperative project to examine the implications of a major earthquake in southern California. The study comprised eight counties: Imperial, Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, and Ventura. Its results will be used as the basis of an emergency response and preparedness exercise, the Great Southern California ShakeOut,
Authors
Lucile M. Jones, Richard Bernknopf, Dale Cox, James Goltz, Kenneth Hudnut, Dennis Mileti, Suzanne Perry, Daniel Ponti, Keith Porter, Michael Reichle, Hope Seligson, Kimberley Shoaf, Jerry Treiman, Anne Wein
Noise in GPS displacement measurements from southern California and southern Nevada
Time series of position changes estimated from data from 236 continuously recording GPS receivers operating in Southern California and Southern Nevada are evaluated for noise models that characterize their temporal correlations. The lengths of the time series range between 3.5 and 10 years. After adjusting these data for postseismic deformation, offsets, and annual periodicities, I find that about
Authors
John O. Langbein
Effects of supershear rupture speed on the high-frequency content of S waves investigated using spontaneous dynamic rupture models and isochrone theory
In this paper we achieve three goals: (1) We demonstrate that crack tips governed by friction laws, including slip weakening, rate- and state-dependent laws, and thermal pressurization of pore fluids, propagating at supershear speed have slip velocity functions with reduced high-frequency content compared to crack tips traveling at subshear speeds. This is demonstrated using a fully dynamic, spon
Authors
A. Bizzarri, Paul A. Spudich
Finding concealed active faults: Extending the southern Whidbey Island fault across the Puget Lowland, Washington
The southern Whidbey Island fault zone (SWIF), as previously mapped using borehole data, potential field anomalies, and marine seismic reflection surveys, consists of three subparallel, northwest trending strands extending ∼100 km from near Vancouver Island to the northern Puget Lowland. East of Puget Sound, the SWIF makes landfall between the cities of Seattle and Everett but is concealed beneath
Authors
Brian Sherrod, Richard J. Blakely, Craig S. Weaver, Harvey M. Kelsey, Elizabeth Barnett, Lee Liberty, Karen L. Meagher, Kristin Pape
Compilation of surface creep on California faults and comparison of WGCEP 2007 deformation model to Pacific-North American plate Mmtion
This Appendix contains 3 sections that 1) documents published observations of surface creep on California faults, 2) constructs line integrals across the WG-07 deformation model to compare to the Pacific - North America plate motion, and 3) constructs strain tensors of volumes across the WG-07 deformation model to compare to the Pacific - North America plate motion. Observation of creep on faults
Authors
Beth A. Wisely, David A. Schmidt, Ray J. Weldon
Paleoseismic Investigations of the Walnut Site on the San Jacinto Fault
The Walnut paleoseismic site is located along the northern San Jacinto fault about 3 km southeast of the San Bernardino, California city center (Figures 1, 2). More than 340 meters of trenches were excavated across the fault zone at this site as part of an Alquist-Priolo fault study (Figure 3). We photographed and logged the SE wall and most of the NE wall of trench 1, both walls of trenches 2 and
Authors
T. E. Fumal, K.J. Kendrick
Empirical estimation of regional time variation in seismicity rates
No abstract available.
Authors
Karen R. Felzer
A-priori rupture models for Northern California Type-A faults
This appendix describes how a-priori rupture models were developed for the northern California Type-A faults. As described in the main body of this report, and in Appendix G, “a-priori” models represent an initial estimate of the rate of single and multi-segment surface ruptures on each fault. Whether or not a given model is moment balanced (i.e., satisfies section slip-rate data) depends on assum
Authors
Chris J. Wills, Ray J. Weldon, Edward H. Field
Conditional, time-dependent probabilities for segmented Type-A faults in the WGCEP UCERF 2
This appendix presents elastic-rebound-theory (ERT) motivated time-dependent probabilities, conditioned on the date of last earthquake, for the segmented type-A fault models of the 2007 Working Group on California Earthquake Probabilities (WGCEP). These probabilities are included as one option in the WGCEP?s Uniform California Earthquake Rupture Forecast 2 (UCERF 2), with the other options being t
Authors
Edward H. Field, Vipin Gupta
Cascadia Subduction Zone
The geometry and recurrence times of large earthquakes associated with the Cascadia Subduction Zone (CSZ) were discussed and debated at a March 28-29, 2006 Pacific Northwest workshop for the USGS National Seismic Hazard Maps.
The CSZ is modeled from Cape Mendocino in California to Vancouver Island in British Columbia. We include the same geometry and weighting scheme as was used in the 2002 mod
Authors
Arthur D. Frankel, Mark D. Petersen
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) seismicity,
Authors
Mark D. Petersen, Charles S. Mueller, Arthur D. Frankel, Yuehua Zeng
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 characterize the
Authors
Karen R. Felzer