Seismic hazard mapping of California considering site effects

E. Kalkan; C.J. Wills; D.M. Branum

doi:10.1193/1.3478312

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Seismic hazard mapping of California considering site effects

E. Kalkan·C.J. Wills·D.M. Branum

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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 VS30. We regrouped these units into seven VS30 values and calculated a probabilistic seismic hazard map for the entire state for each VS30 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.

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Source-reported bounding extent: 32.5° to 42° latitude; -124.4° to -114.1° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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E. Kalkan, C.J. Wills, D.M. Branum. 2010-11-01. Seismic hazard mapping of California considering site effects. https://doi.org/10.1193/1.3478312

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