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 Beroza, a seismologist with Stanford University, made several distinctions regarding the 1906 and 1989 events. Near Loma Prieta, the 1906 rupture was more shallow, had more strike-slip, and occurred on a fault that was near vertical. The 1989 event's oblique-slip rupture was at 10 km and below on a fault plane that dipped 70° to the southwest. Because much of the slip in 1989 occurred at depth and the rupture propagated up dip, Beroza proposed that the overlying San Andreas Fault actually inhibited further rupture and also maintains that the occurrence of an event at the location that was forecast