|
|
|
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Woodward-Clyde Federal Services, 566 El Dorado Street, Pasadena, California 91101rwgrave0{at}wcc.com
Abstract
The 1994 Northridge earthquake produced ground motions in the northwest portion of the Los Angeles basin that were significantly larger than rock-site motions observed at locations just north of the basin. The Santa Monica area was hit particularly hard, with numerous structures being damaged or destroyed by the strong ground shaking. In this region, the basin-edge geology is controlled by the active strand of the east-west-striking Santa Monica fault, and virtually all of the structural damage occurred at or south of the fault location. We have used 2D finite-difference ground-motion simulations to investigate the effect of the basin-edge structure in amplifying ground response. Constraints on the basin-edge structure come from geologic cross sections, geophysical data, and seismological observations. Our simulations indicate that the shallow basin-edge structure (1 km deep) formed by the active strand of the Santa Monica fault creates a large amplification in motions immediately south of the fault scarp, in very good agreement with mainshock damage patterns, recorded ground motions, and locations of elevated site response. This large amplification results from constructive interference of direct waves with the basin-edge-generated surface waves and is quite similar to the basin-edge effect associated with the 1995 Kobe earthquake. In addition, we find that focusing effects created by the deeper basin structure (3 to 4 km deep) cannot explain the large motions observed immediately south of the fault scarp. This strongly suggests that the deep-basin focusing models proposed by Gao et al. (1996) and Alex and Olsen (1998) are not likely explanations of the observed pattern of ground-motion amplification in the Santa Monica area.
This article has been cited by other articles:
![]() |
A. Frankel, W. Stephenson, and D. Carver Sedimentary Basin Effects in Seattle, Washington: Ground-Motion Observations and 3D Simulations Bulletin of the Seismological Society of America, June 1, 2009; 99(3): 1579 - 1611. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Bindi, S. Parolai, F. Cara, G. Di Giulio, G. Ferretti, L. Luzi, G. Monachesi, F. Pacor, and A. Rovelli Site Amplifications Observed in the Gubbio Basin, Central Italy: Hints for Lateral Propagation Effects Bulletin of the Seismological Society of America, April 1, 2009; 99(2A): 741 - 760. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. D. Catchings, G. Gandhok, M. R. Goldman, D. Okaya, M. J. Rymer, and G. W. Bawden Near-Surface Location, Geometry, and Velocities of the Santa Monica Fault Zone, Los Angeles, California Bulletin of the Seismological Society of America, February 1, 2008; 98(1): 124 - 138. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Snelson, T. M. Brocher, K. C. Miller, T. L. Pratt, and A. M. Trehu Seismic Amplification within the Seattle Basin, Washington State: Insights from SHIPS Seismic Tomography Experiments Bulletin of the Seismological Society of America, October 1, 2007; 97(5): 1432 - 1448. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. K. McPhee, V. E. Langenheim, S. Hartzell, R. J. McLaughlin, B. T. Aagaard, R. C. Jachens, and C. McCabe Basin Structure beneath the Santa Rosa Plain, Northern California: Implications for Damage Caused by the 1969 Santa Rosa and 1906 San Francisco Earthquakes Bulletin of the Seismological Society of America, October 1, 2007; 97(5): 1449 - 1457. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. M. Atkinson Challenges in seismic hazard analysis for continental interiors Geological Society of America Special Papers, January 1, 2007; 425(0): 329 - 344. [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] |
||||
![]() |
C. K. Saikia, A. Pitarka, and G. A. Ichinose Effects of Irregular Structure of the Mississippi Embayment on Ground-Motion Amplification Bulletin of the Seismological Society of America, August 1, 2006; 96(4A): 1448 - 1473. [Abstract] [Full Text] [PDF] |
||||
![]() |
G.-Q. Wang, G.-Q. Tang, D. M. Boore, G. Van Ness Burbach, C. R. Jackson, X.-Y. Zhou, and Q.-L. Lin Surface Waves in the Western Taiwan Coastal Plain from an Aftershock of the 1999 Chi-Chi, Taiwan, Earthquake Bulletin of the Seismological Society of America, June 1, 2006; 96(3): 821 - 845. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Li, W. S. D. Wilcock, T. L. Pratt, C. M. Snelson, and T. M. Brocher Seismic Attenuation Structure of the Seattle Basin, Washington State, from Explosive-Source Refraction Data Bulletin of the Seismological Society of America, April 1, 2006; 96(2): 553 - 571. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.-Y. Wang, A. Wong, D. S. Dreger, and M. Manga Liquefaction Limit during Earthquakes and Underground Explosions: Implications on Ground-Motion Attenuation Bulletin of the Seismological Society of America, February 1, 2006; 96(1): 355 - 363. [Abstract] [Full Text] [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] |
||||
![]() |
Y. Choi, J. P. Stewart, and R. W. Graves Empirical Model for Basin Effects Accounts for Basin Depth and Source Location Bulletin of the Seismological Society of America, August 1, 2005; 95(4): 1412 - 1427. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Hartzell, M. Guatteri, P. M. Mai, P.-C. Liu, and M. Fisk Calculation of Broadband Time Histories of Ground Motion, Part II: Kinematic and Dynamic Modeling Using Theoretical Green's Functions and Comparison with the 1994 Northridge Earthquake Bulletin of the Seismological Society of America, April 1, 2005; 95(2): 614 - 645. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. W. Graves and D. J. Wald Observed and Simulated Ground Motions in the San Bernardino Basin Region for the Hector Mine, California, Earthquake Bulletin of the Seismological Society of America, February 1, 2004; 94(1): 131 - 146. [Abstract] [Full Text] [PDF] |
||||
![]() |
The Basin-Edge Effect from Weak Ground Motions Across the Fault-Bounded Edge of the Lower Hutt Valley, New Zealand Bulletin of the Seismological Society of America, December 1, 2003; 93(6): 2703 - 2716. |
||||
![]() |
Empirical Corrections for Basin Effects in Stochastic Ground-Motion Prediction, Based on the Los Angeles Basin Analysis Bulletin of the Seismological Society of America, August 1, 2003; 93(4): 1679 - 1690. |
||||
![]() |
Site Response, Shallow Shear-Wave Velocity, and Wave Propagation at the San Jose, California, Dense Seismic Array Bulletin of the Seismological Society of America, February 1, 2003; 93(1): 443 - 464. |
||||
![]() |
Wave Propagation and Site Response in the Santa Clara Valley Bulletin of the Seismological Society of America, February 1, 2003; 93(1): 480 - 500. |
||||
![]() |
3D Heterogeneous Staggered-Grid Finite-Difference Modeling of Seismic Motion with Volume Harmonic and Arithmetic Averaging of Elastic Moduli and Densities Bulletin of the Seismological Society of America, December 1, 2002; 92(8): 3042 - 3066. |
||||
![]() |
Separation of Site Effects and Structural Focusing in Santa Monica, California: A Study of High-Frequency Weak Motions from Earthquakes and Blasts Recorded during the Los Angeles Region Seismic Experiment Bulletin of the Seismological Society of America, December 1, 2002; 92(8): 3134 - 3151. |
||||
![]() |
Delineation of Faulting and Basin Geometry along a Seismic Reflection Transect in Urbanized San Bernardino Valley, California Bulletin of the Seismological Society of America, August 1, 2002; 92(6): 2504 - 2520. |
||||
![]() |
Edge-Diffracted 1-Sec Surface Waves Observed in a Small-Size Intramountain Basin (Colfiorito, Central Italy) Bulletin of the Seismological Society of America, December 1, 2001; 91(6): 1851 - 1866. |
||||
![]() |
Observations of Basin Ground Motions from a Dense Seismic Array in San Jose, California Bulletin of the Seismological Society of America, February 1, 2001; 91(1): 1 - 12. |
||||
![]() |
E. H. Field and the SCEC Phase III Working Group Accounting for Site Effects in Probabilistic Seismic Hazard Analyses of Southern California: Overview of the SCEC Phase III Report Bulletin of the Seismological Society of America, December 1, 2000; 90(6B): S1 - S31. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. B. Joyner Strong Motion from Surface Waves in Deep Sedimentary Basins Bulletin of the Seismological Society of America, December 1, 2000; 90(6B): S95 - S112. [Abstract] [Full Text] [PDF] |
||||
![]() |
Three-Dimensional Simulations of Ground Motions in the Seattle Region for Earthquakes in the Seattle Fault Zone Bulletin of the Seismological Society of America, October 1, 2000; 90(5): 1251 - 1267. |
||||
![]() |
P. M. Davis, J. L. Rubinstein, K. H. Liu, S. S. Gao, and L. Knopoff Northridge Earthquake Damage Caused by Geologic Focusing of Seismic Waves Science, September 8, 2000; 289(5485): 1746 - 1750. [Abstract] [Full Text] |
||||
![]() |
Integrated Use of Seismograph and Strong-Motion Data to Determine Soil Amplification: Response of the Fraser River Delta to the Duvall and Georgia Strait Earthquakes Bulletin of the Seismological Society of America, August 1, 2000; 90(4): 1028 - 1040. |
||||
![]() |
3D Fourth-Order Staggered-Grid Finite-Difference Schemes: Stability and Grid Dispersion Bulletin of the Seismological Society of America, June 1, 2000; 90(3): 587 - 603. |
||||
![]() |
S. Hartzell, S. Harmsen, A. Frankel, and S. Larsen Calculation of broadband time histories of ground motion: Comparison of methods and validation using strong-ground motion from the 1994 Northridge earthquake Bulletin of the Seismological Society of America, December 1, 1999; 89(6): 1484 - 1504. [Abstract] [PDF] |
||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |