Near-Surface Shear-Wave Velocities determined using the Community Seismic Network (CSN)

Dandan Zhang, & Robert W. Clayton

Published August 13, 2017, SCEC Contribution #7545, 2017 SCEC Annual Meeting Poster #275

Near-surface shear-wave velocities (Vs30, for example) are used to characterize the site response for earthquake hazard. Unfortunately, most of the measurements are done by proxies like surface slope because the traditional seismic network such at the Southern California Seismic Network (SCSN) are sparse when it comes to this type of measurement. In this study, we use a denser network – the Community Seismic Network – located on 100 school campus in northern Los Angeles to measure the velocities. This is a 15km by 15km area. We use spectral ratios between the horizontal and vertical components (H/V ratio) of ambient noise to constrain the velocities in the top 100m (Nakamura’s method). Since observations are taken over two years, we also have robust estimates of the variance.

Citation
Zhang, D., & Clayton, R. W. (2017, 08). Near-Surface Shear-Wave Velocities determined using the Community Seismic Network (CSN) . Poster Presentation at 2017 SCEC Annual Meeting.

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