The 1989 Loma Prieta earthquake Catastrophe occurred Coming_to_be in Northern California on October 17 at local time ( 1989-10-18 00:04 UTC ) .

The shock Catastrophe was centered Placing 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 Name_conferral for the nearby Loma Prieta Peak in the Santa Cruz Mountains .

The Loma Prieta segment of the San Andreas Fault System had been relatively inactive since the 1906 San Francisco earthquake Catastrophe ( to the degree that it was designated Coming_to_be a seismic gap ) until two moderate foreshocks Attack occurred Coming_to_be in June 1988 and again in August 1989 .

As the largest earthquake in California since the 1989 Loma Prieta event several years earlier , the mainshock caused Causation a non-destructive tsunami Catastrophe that quickly reached Arriving the coast , and eventually Alaska and Hawaii several hours later .