The earthquake struck 23 miles SE of Clexico, California on Wednesday, December 30, 2009 at 10:48:57 AM at epicenter. The depth of the earthquake (hypocenter) was only 3.7 miles which means it was a very shallow earthquake - capable of doing more damage at the surface.

The first strong earthquake listed in earthquake annals for California occurred in the Los Angeles region in 1769, probably near the San Andreas Fault. Four violent shocks were recorded by the Gaspar de Portola Expedition, in camp about 30 miles southeast of Los Angeles center. Most authorities speculate, even though the record is very incomplete, that this was a major earthquake.

Forty persons attending church at San Juan Capistrano on December 8, 1812, were killed by a strong earthquake that destroyed the church. Many mission buildings were severely damaged there and at San Gabriel. The shock probably centered on a submarine fault offshore.

A violent shock near Fort Tejon in January 1857 threw down buildings and large trees at the Fort. It was also severe in Los Angeles, San Francisco, and Sacramento. This earthquake has been compared to that of April 1906; both caused extensive displacement along the San Andreas Fault. One source notes, "The magnitude of the two events cannot have differed greatly."

A strong earthquake occurred on the Hayward Fault, the principal active branch of the San Andreas in central California, in October 1868. Some 30 persons were killed in the region. Damage was severe at San Francisco; many buildings were wrecked at Hayward and San Leandro. Until 1906, this shock was often referred to as "the great earthquake."

Below is a map showing recent earthquakes including the location of today's 5.8 earthquake (large red square). To learn more about earthquakes, tectonic plates, and our infamous San Andreas Fault, take our information-packed tour called "It's Our Fault".