Historic Earthquakes

West of Ventura, California
in the Santa Barbara Channel
1812 December 21 19:00 UTC
Magnitude 7.1

This major earthquake caused damage in Santa Barbara, Ventura, and northern Los Angeles Counties. One fatality was reported, but many lives probably were saved by a strong foreshock about 15 minutes earlier that sent alarmed residents fleeing from buildings. The earthquakes also may have generated a tsunami because there were several reports of sea waves following the earthquakes. The sea waves reportedly did not cause loss of life or substantial loss of property.

At Santa Barbara Mission, all buildings sustained many cracks, and one chapel was flattened. The ground "opened up" at this area to such an extent "that it caused horror." At the Santa Barbara Presidio, all the buildings were left uninhabitable. The church at La Purisima Concepcion Mission (Lompoc) was ruined; some of the other buildings were "flattened to the ground"; and others required extensive repair. Part of the adobe garden wall collapsed, and the part remaining nearly fell. Damage at the Santa Ynez Mission was considerable but not so severe as at Santa Barbara and Purisima Missions. A corner of the church fell; many new houses were demolished; and many support walls were cracked. Property loss was less severe at the San Buenaventura Mission (Ventura) and the San Fernando Ray Mission. Aftershocks were reported at Santa Barbara through April 1813.

Abridged from Seismicity of the United States, 1568-1989 (Revised), by Carl W. Stover and Jerry L. Coffman, U.S. Geological Survey Professional Paper 1527, United States Government Printing Office, Washington: 1993.