1989 Loma Prieta earthquake larger loss of life, as several of the Bay Area's major transportation structures suffered catastrophic failures. The collapse of a section of the double-deck Nimitz Freeway in Oakland was the site of the largest number of casualties for the event, but the collapse of man-made structures and other related accidents contributed to casualties occurring in San Francisco, Los Altos, and Santa Cruz. The history of earthquake investigations in California has been largely focused on the San Andreas Fault System, due to its strong influence in the state as the boundary between the Pacific Plate and the North American Plate; it
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