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An Updated Vs30 Map for California with Geologic and Topographic Constraints (ver. 1.1, July 2022)

Published by U.S. Geological Survey | Department of the Interior | Metadata Last Checked: January 27, 2026 | Last Modified: 2022-07-12T00:00:00Z
This data release provides a map of the time-averaged shear-wave velocity in the upper 30 m (Vs30) for California using the method described by Thompson and others (2014). There are two adjustments to the algorithm described by Thompson and others (2014), which is built on the geology-based Vs30 map by Wills and Clahan (2006). In this data release, we use the Wills and others (2015) updated geology-based Vs30 map. The second change is that we have adjusted the kriging procedure so that measured Vs30 values do not affect the predictions across distinctly different geologic units.

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