Seismic Hazard Mapping of California considering Site Effects

Abstract

In this paper, we have combined the U.S. Geological Survey's National Seismic Hazard Maps model with the California geologic map showing 17 generalized geologic units that can be defined by their V_S₃₀. We regrouped these units into seven V_S₃₀ values and calculated a probabilistic seismic hazard map for the entire state for each V_S₃₀ value. By merging seismic hazard maps based on the seven different V_S₃₀ values, a suite of seismic hazard maps was computed for 0.2 and 1.0 s spectral ordinates at 2% probability of exceedance (PE) in 50 years. The improved hazards maps explicitly incorporate the site effects and their spatial variability on ground motion estimates. The spectral acceleration (SA) at 1.0 s map of seismic shaking potential for California has now been published as California Geological Survey Map Sheet 48.

Get full access to this article

View all access options for this article.

References

American Society of Civil Engineers (ASCE), 2007. Seismic Rehabilitation of Existing Buildings, p 423, ISBN: 9780784408841.

Anderson

J. G.

, Bodin

, Brune

J. N.

, Prince

, Singh

S. K.

, Quass

, and Onate

, 1986. Strong ground motion from the Michoacan, Mexico, earthquake, Science 233, 1043–1049.

Boore

D. M.

, and Atkinson

, 2008. Ground-motion prediction equations for the average horizontal component of PGA, PGV, and 5%-Damped PSA at spectral periods between 0.01 s and 10.0 s, Earthquake Spectra 24, 99–138.

Borcherdt

R. D.

, 2002. Empirical evidence for site coefficients in building code provisions, Earthquake Spectra 18, 189–217.

Bouchon

, and Baker

J. S.

, 2006. Seismic response of a hill: The example of Tarzana, California, Bull. Seismol. Soc. Am. 86, 66–72.

Branum

, Harmsen

, Kalkan

, Petersen

, and Wills

, 2008. Earthquake Shaking Potential for California: California Geological Survey Map Sheet 48, Sacramento CA, also available at http://www.conservation.ca.gov/cgs/information/publications/ms/Documents/MS48_revised.pdf (accessed on 13 May 2009).

Campbell

, and Bozorgnia

, 2008. NGA ground-motion model for the geometric mean horizontal component of PGA, PGV, PGD, and 5%-damped linear elastic response Spectra for Periods Ranging from 0.01 to 10 s, Earthquake Spectra 24, 139–171.

Chiou

, and Youngs

, 2008. An NGA model for the average horizontal component of peak ground-motion and response spectra, Earthquake Spectra 24, 173–215.

Harmsen

, 2009. Personal communication.

10.

Holzer

T. L.

, 1994. Loma Prieta damage largely attributed to enhanced ground shaking, EOS Trans. Am. Geophys. Union 75, 299–301.

11.

Holzer

T. L.

, Noce

T. E.

, and Bennett

M. J.

, 2009. Scenario liquefaction hazard maps of Santa Clara Valley, Northern California, Bull. Seismol. Soc. Am. 99, 367–381.

12.

Petersen

M. D.

, Frankel

A. D.

, Harmsen

S. C.

, Mueller

C. S.

, Haller

K. M.

, Wheeler

R. L.

, Wesson

R. L.

, Zeng

Y. B.

, Oliver

, Perkins

D. M.

, Luco

, Field

E. H.

, Wills

C. J.

, and Rukstales

K. S.

, 2008. Documentation for the 2008 Update of the United States National Seismic Hazard Maps, U.S. Geological Survey Open-File Report, 2008-1128, 61 pp.

13.

Seekins

L. C.

, Boatwright

, and Fumal

, 2000. Soil Type and Shaking Hazard in the San Francisco Bay Area, U.S. Geological Survey, http://earthquake.usgs.gov/regional/nca/soiltype/.

14.

Wills

C. J.

, Petersen

, Bryant

W. A.

, Reichle

, Saucedo

G. J.

, Tan

, Taylor

, and Treiman

, 2000. A site conditions map for California based on geology and shear-wave velocity, Bull. Seismol. Soc. Am. 90, 187–208.

15.

Wills

C. J.

, and Clahan

K. B.

, 2006. Developing a map of geologically defined site condition categories for California. Bull. Seismol. Soc. Am. 96, 1483–1501.

16.

Wills

C. J.

, and Silva

, 1998, Shear wave velocity characteristics of geologic units in California, Earthquake Spectra 14, 533–556.

17.

Working Group on California Earthquake Probabilities, 2008. The Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2), U.S. Geological Survey Open-File Report 2007-1437 and California Geological Survey Special Report 203, http://pubs.usgs.gov/of/2007/1091/ (accessed on 13 May 2009).