| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 U.S. Geological Survey
345
Middlefield Road
MS 977
Menlo Park, California 94025
A compilation of compressional-wave (Vp) and shear-wave (Vs) velocities and densities for a wide variety of common lithologies is used to define new nonlinear, multivalued, and quantitative relations between these properties for the Earth's crust. Wireline borehole logs, vertical seismic profiles, laboratory measurements, and seismic tomography models provide a diverse dataset for deriving empirical relations between crustal Vp and Vs. The proposed Vs as a function of Vp relations fit Vs and Vp borehole logs in Quaternary alluvium and Salinian granites as well as laboratory measurements over a 7-km/sec-wide range in Vp. The relations derived here are very close to those used to develop a regional 3D velocity model for southern California, based on pre-1970 data, and thus provide support for that model. These data, and these relations, show a rapid increase in Vs as Vp increases to 3.5 km/sec leading to higher shear-wave velocities in young sedimentary deposits than commonly assumed. These relations, appropriate for active continental margins where earthquakes are prone to occur, suggests that amplification of strong ground motions by shallow geologic deposits may not be as large as predicted by some earlier models.
This article has been cited by other articles:
|
|
 |
|
  T. M. Brocher Compressional and Shear-Wave Velocity versus Depth Relations for Common Rock Types in Northern California Bulletin of the Seismological Society of America, April 1, 2008; 98(2): 950 - 968. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Rodgers, N. A. Petersson, S. Nilsson, B. Sjogreen, and K. McCandless Broadband Waveform Modeling of Moderate Earthquakes in the San Francisco Bay Area and Preliminary Assessment of the USGS 3D Seismic Velocity Model Bulletin of the Seismological Society of America, April 1, 2008; 98(2): 969 - 988. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. T. Aagaard, T. M. Brocher, D. Dolenc, D. Dreger, R. W. Graves, S. Harmsen, S. Hartzell, S. Larsen, and M. L. Zoback Ground-Motion Modeling of the 1906 San Francisco Earthquake, Part I: Validation Using the 1989 Loma Prieta Earthquake Bulletin of the Seismological Society of America, April 1, 2008; 98(2): 989 - 1011. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. T. Aagaard, T. M. Brocher, D. Dolenc, D. Dreger, R. W. Graves, S. Harmsen, S. Hartzell, S. Larsen, K. McCandless, S. Nilsson, et al. Ground-Motion Modeling of the 1906 San Francisco Earthquake, Part II: Ground-Motion Estimates for the 1906 Earthquake and Scenario Events Bulletin of the Seismological Society of America, April 1, 2008; 98(2): 1012 - 1046. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. L. Hardebeck, A. J. Michael, and T. M. Brocher Seismic Velocity Structure and Seismotectonics of the Eastern San Francisco Bay Region, California Bulletin of the Seismological Society of America, June 1, 2007; 97(3): 826 - 842. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Hartzell, S. Harmsen, R. A. Williams, D. Carver, A. Frankel, G. Choy, P.-C. Liu, R. C. Jachens, T. M. Brocher, and C. M. Wentworth Modeling and Validation of a 3D Velocity Structure for the Santa Clara Valley, California, for Seismic-Wave Simulations Bulletin of the Seismological Society of America, October 1, 2006; 96(5): 1851 - 1881. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. L. Boness and M. D. Zoback Mapping stress and structurally controlled crustal shear velocity anisotropy in California Geology, October 1, 2006; 34(10): 825 - 828. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Veenstra, D. H. Christensen, G. A. Abers, and A. Ferris Crustal thickness variation in south-central Alaska Geology, September 1, 2006; 34(9): 781 - 784. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P.K.H. Maguire, G.R. Keller, S.L. Klemperer, G.D. Mackenzie, K. Keranen, S. Harder, B. O'Reilly, H. Thybo, L. Asfaw, M.A. Khan, et al. Crustal structure of the northern Main Ethiopian Rift from the EAGLE controlled-source survey; a snapshot of incipient lithospheric break-up Geological Society, London, Special Publications, January 1, 2006; 259(1): 269 - 292. [Abstract] [PDF]
|
|
|
|
|
|
T. M. Brocher A Regional View of Urban Sedimentary Basins in Northern California Based on Oil Industry Compressional-Wave Velocity and Density Logs Bulletin of the Seismological Society of America, December 1, 2005; 95(6): 2093 - 2114. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
