The Golden Gate Bridge

1971 San Fernando Quake

TIME   February 9, 1971 / 6:01 am PST

LOCATION   Also known as the Sylmar Earthquake , this earthquake occurred on the San Fernando fault zone .The total surface rupture was roughly 19 km (12 miles) long. The maximum slip was up to 2 meters (6 feet). During quake, the San Gabriel Mountains back of San Fernando were lifted several feet.

MAGNITUDE   6.6

HUMAN/PHYSICAL TOLL The earthquake caused 65 deaths and over $500 million in property damage. Most of the deaths occurred when the Veteran's Administration Hospital collapsed. Several other hospitals, including the Olive View Community Hospital in Sylmar (pictured here) suffered severe damage. Newly constructed freeway overpasses also collapsed, in damage scenes similar to those that occurred 23 years later in the 1994 Northridge Earthquake . Loss of life could have been much greater had the earthquake struck at a busier time of day.

Sylmar Earthquake

LESSONS LEARNED In response to this earthquake, building codes were strengthened and the Alquist Priolo Special Studies Zone Act was passed in 1972. The purpose of this act is to prohibit the location of most structures for human occupancy across the traces of active faults and to thereby mitigate the hazard of fault rupture.

Sources: Southern California Earthquake Data Center and from California Geology, April/May 1971, Vol. 24, No. 4-5.