Map Sheet 48 (2025 update) - Site Condition

This map shows distribution of the time-averaged shear-wave velocity in the upper 30 m (Vs30) for California. Vs30 is used as a proxy for local geologic site condition in ground motion hazard calculations. The map is produced using data provided by Thompson (ver. 2.0, July 2022), which is based on the method described by Thompson and others (2014) with adjustments (see Thompson, 2022 for detail). Vs30 unit is m/s. Data resolution is 3 arcseconds (approximately 90 m). Due to software limitations, symbology cannot be added to this service. To match the symbology used in the MS48 Additional Maps application, use the following configuration: Esri Color Ramp: Yellow to Dark Red Number of Classes: 5 Classes & Hex Codes: 176.1 - 300: #F4FE93 300 - 450: #F6DC6A 450 - 600: #F2B841 600 - 725: #BA671A 725 - 1,473.3: #810A01