Earthquake Information
Chronological Earthquake Index
San Fernando Earthquake
TYPE OF FAULTING: thrust
TIME: February 9, 1971 / 6:01 am PST
LOCATION: 34° 24.67' N, 118° 24.04' W
MAGNITUDE: MW6.5
DEPTH: 8.4 km
FAULT INVOLVED: San Fernando fault zone; minor offset reported on the eastern Santa Susana fault zone
Also known as the Sylmar Earthquake, this earthquake occurred on the San Fernando fault zone, a zone of thrust faulting which broke the surface in the Sylmar-San Fernando Area. The total surface rupture was roughly 19 km (12 miles) long. The maximum slip was up to 2 meters (6 feet).
The earthquake caused over $500 million in property damage and 65 deaths. Most of the deaths occurred when the Veteran's Administration Hospital collapsed. Several other hospitals, including the Olive View Community Hospital in Sylmar (pictured below) suffered severe damage. Newly constructured freeway overpasses also collapsed, in damage scenes similar to those which 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.
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 mitigate thereby the hazard of fault rupture.
