The northern segment of the fault runs from Hollister , through the Santa Cruz Mountains , epicenter of the 1989 Loma Prieta earthquake , then up the San Francisco Peninsula , where it was first identified by Professor Lawson in 1895 , then offshore at Daly City near Mussel Rock . This is the approximate location of the epicenter of the 1906 San Francisco earthquake . The fault returns onshore at Bolinas Lagoon just north of Stinson Beach in Marin County . It returns underwater through the linear trough of Tomales Bay which separates the Point Reyes Peninsula from the mainland , runs just east of Bodega Head through Bodega Bay and back underwater , returning onshore at Fort Ross . ( In this region around the San Francisco Bay Area several significant " sister faults " run more-or-less parallel , and each of these can create significantly destructive earthquakes . ) From Fort Ross , the northern segment continues overland , forming in part a linear valley through which the Gualala River flows . It goes back offshore at Point Arena . After that , it runs underwater along the coast until it nears Cape Mendocino , where it begins to bend to the west , terminating at the Mendocino Triple Junction
1989 Loma Prieta earthquake
1989 Loma Prieta earthquake
San Andreas Fault