The first struck the far southern deserts of the state near the Mexican border at 2:40 a.m. local time. The 3.5 magnitude tremor was centered about 17 miles (27 km) north-northeast of the small town of Ocotillo. The same area has received several comparable quakes in recent weeks.
Southern parts of the San Francisco Bay Area felt the next seismic slip at 4:10 p.m. on Sunday afternoon. The Public Seismic Network of San Jose reported that the quake was felt in Aptos, Redwood City and Los Altos.
The last tremor rocked the seismically active region around Parkfield at 4:34 a.m. on Tuesday. Local residents described the relatively mild quake as a "big pop," which was followed by a rumbling.