2014 South Napa earthquake location. At least twelve aftershocks followed, including one of magnitude 3.9. The earthquake was the largest earthquake in the Bay Area since the magnitude 6.9 1989 Loma Prieta earthquake. Governor Jerry Brown declared a state of emergency due to the severe damage and the possibility of aftershocks. President Obama declared a major disaster for Napa and Solano counties. Several older commercial buildings in downtown Napa showed signs of extensive external damage even though many had been retrofitted for earthquake safety protection. The Goodman Library, Napa County Courthouse Plaza, Sam Kee Laundry Building, Downtown U.S. Post Office, Alexandria Hotel and Annex,
1989 Loma Prieta earthquake oblique reverse faults and were within of the M6.9 Loma Prieta mainshock epicenter, near the intersection of the San Andreas and Sargent faults. Total displacement for these shocks was relatively small (approximately of strike-slip and substantially less reverse-slip) and although they occurred on separate faults and well before the mainshock, a group of seismologists considered these to be foreshocks due to their location in space and time relative to the main event. Each event's aftershock sequence and effect on stress drop was closely examined, and their study indicated that the shocks affected the mainshock's rupture process. Following the August 8,