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Vs30, the time-averaged shear-wave velocity ( Vs) in the upper 30 meters, is a key index adopted by the earthquake engineering community to account for seismic site conditions. USGS has compiled measured VS30 funded by the USGS and other governmental agencies for 4389 sites in the United States.
Vs30, the time-averaged shear-wave velocity ( Vs) in the upper 30 meters, is a key index adopted by the earthquake engineering community to account for seismic site conditions. USGS has compiled measured VS30 funded by the USGS and other governmental agencies for 4389 sites in the United States.