Comparison of site dominant frequency from earthquake and microseismic data in California

Behzad Hassani; Alan Yong; Gail M. Atkinson; Tian Feng; Lingseng Meng

doi:10.1785/0120180267

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Comparison of site dominant frequency from earthquake and microseismic data in California

Behzad Hassani·Alan Yong·Gail M. Atkinson·Tian Feng·Lingseng Meng

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Abstract

An important predictive variable for site amplification is the site dominant frequency ( ⁠ƒ d ⁠ ). At seismic monitoring stations, ƒ d can be calculated from the peak of the horizontal‐to‐vertical spectral ratios (HVSRs) obtained from earthquake recordings (eHVSR). For other sites, ƒ d can be estimated from microseismic (mHVSR) observations. We compare the ƒ d values derived from eHVSR (5% damped response spectra from the Next Generation Attenuation‐West2 [NGA‐West2] database; Ancheta et al. , 2014 ) with those derived from mHVSR (Fourier spectra from Yong et al. , 2013 ) for seismic stations in California. We show that the logarithm of eHVSR ƒ d scales linearly with the logarithm of mHVSR ƒ d ⁠ , with a standard deviation of 0.14log 10 units for mHVSR ƒ d larger than 0.2 Hz. The relationship holds for microseismic surveys at distances up to 300 m away from the seismic stations. The results of this study have beneficial implications for the characterization of site response in modern ground‐motion models as well as in building codes.

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Bulletin of the Seismological Society of America Article

Source-reported bounding extent: 32.534156° to 42.009247° latitude; -124.409591° to -114.134768° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Behzad Hassani, Alan Yong, Gail M. Atkinson, Tian Feng, Lingseng Meng. 2019-03-19. Comparison of site dominant frequency from earthquake and microseismic data in California. https://doi.org/10.1785/0120180267

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