Study of Near-Source Earthquake Ground Motions of Three California Earthquakes:North ridge, Whittier, and Landers

摘要

Three datasets were analyzed and maps were prepared of near source ground motionsassociated with the Whittier, Northridge, and Landers earthquakes in southern California. Vertical motions were enhanced in the near source area of high angle thrust faults at Whittier and Landers, similar to Northridge. Factors are provided for the enhancement in terms of site conditions. Distance factors were established with vertical-to-horizontal ratios. Area patterns of earthquake ground motions were plotted with relation to known faults.