Map Sheet 48 (2025 update) - Ground Motion from SA20 (2% in 50 years)

This image service is part of a collection of maps for PGA, PGV and spectral accelerations at 0.2 s (SA02), 1.0 s (SA10), and 2.0 s (SA20) to illustrate seismic hazards in California. For each ground motion parameter, maps at two different hazard levels were presented: one with a 2% probability of being exceeded in 50 years (equivalent to 2,475-year recurrence interval) and the other with 10% probability of being exceeded in 50 years (equivalent to 475-year recurrence interval). The ArcGIS Online interface allows users to select any two ground motion hazard maps to compare side by side. Ground motion parameters were calculated using the 2023 update of the U.S. Geological Survey National Seismic Hazard Model. See the “Scientific Background” on MS48 webpage for detailed information.Due to software limitations, symbology cannot be added to this service. To match the symbology used in the MS48 Ground Motion application, use the following configuration:Esri Color Ramp: MagmaMinimum: 4.41 gMaximum: 0.032 gGamma: 1