1989 Loma Prieta earthquake earthquake precursor, more recent studies have cast doubt on the connection, attributing the Corralitos signals to either unrelated magnetic disturbance or, even more simply, to sensor-system malfunction. The earthquake caused severe damage in some very specific locations in the San Francisco Bay Area, most notably on unstable soil in San Francisco and Oakland. Oakland City Hall was evacuated after the earthquake until a US$80M seismic retrofit and hazard abatement work was completed in 1995. Many other communities sustained severe damage throughout the region located in Alameda, San Mateo, Santa Clara, San Benito, Santa Cruz and Monterey counties. Major property damage
1989 Loma Prieta earthquake 1989 Loma Prieta earthquake The 1989 Loma Prieta earthquake occurred in Northern California on October 17 at local time (1989-10-18 00:04 UTC). The shock was centered in The Forest of Nisene Marks State Park approximately northeast of Santa Cruz on a section of the San Andreas Fault System and was named for the nearby Loma Prieta Peak in the Santa Cruz Mountains. With a moment magnitude of 6.9 and a maximum Mercalli intensity of IX ("Violent"), the shock was responsible for 63 deaths and 3,757 injuries. The Loma Prieta segment of the San Andreas Fault System had been relatively inactive