A Review of the Seismicity of the California Islands

The historic seismicity of the California Islands region is represented by several significant events including the 1812 (M=7.1) earthquake which occurred near Santa Barbara, the 1812 event (M=6.9) near San Juan Capistrano, and M=5.9-6.0 earthquakes in 1862 near San Diego and 1883 near Santa Barbara. Recent activity (1900-1988) is generated by both onshore and offshore faults for M=5.0-6.0 events. Analysis of focal mechanisms by various investigators indicated both strike-slip and reverse faulting which are produced by NE-SW stresses associated with the plate motions.