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A Generic Velocity Profile for Basin Sediments in California Conditioned on VS30

Jian Shi, & Domniki Asimaki

Published May 23, 2018, SCEC Contribution #7287

The near‐surface soil layers of sedimentary basins play a critical role in modifying the amplitude, frequency, and duration of earthquake ground shaking and, thus, are an important factor to consider in ground‐motion simulations, the development of site amplification factors, and earthquake hazard evaluations on a regional scale. In this article, we present a sediment velocity model (SVM) that translates Vs30 and a proxy that describes the stiffness of the near‐surface sediments into a 1D velocity profile suitable for use in wave‐propagation‐based ground‐motion predictions. We develop the SVM based on the statistics of 914 measured velocity profiles. We conduct a validation study and show that the SVM can satisfactorily predict both 1D shear‐wave velocity profiles and linear site amplification factors. Lastly, we propose two correlations that enable the stochastic realization of the SVM profiles.

Shi, J., & Asimaki, D. (2018). A Generic Velocity Profile for Basin Sediments in California Conditioned on VS30. Seismological Research Letters, 89(4), 1397-1409. doi: 10.1785/0220170268.