Bay Area hit by two earthquakes - 3.5 and 4.0 - moments apart
A shallow magnitude 4.0 earthquake hit the El Cerrito area at 5:33 a.m. Moments before, the same area was hit by a 3.5 quake, officials said.
According to the USGS' "Did You Feel It?" service, the temblor was felt from Santa Cruz to beyond Santa Rosa. It was particularly reported by Oakland, Berkeley and other East Bay communities close to the epicenter.
BART temporarily halted service for track inspection but the transit service quickly resumed.
According to the U.S. Geological Survey, the epicenter was a mile from East Richmond Heights, two miles from Richmond, four miles from Berkeley and 13 miles from San Francisco City Hall.
There were several smaller temblors after the 4.0 jolt.
In the past 10 days, there have been two earthquakes magnitude 3.0 and greater centered nearby.
Read more about California earthquakes on L.A. Now.
Seismologists believe the quake occurred along the Hayward fault.
Seismologists said the 4.0 earthquake that rattled the Bay Area on Monday is a reminder of the danger posed by the fault.
Experts have long said the Hayward fault is overdue for a major temblor, which could be destructive given it runs under numerous population centers.
The Hayward fault runs along the eastern side of San Francisco Bay and has long been considered one of the most dangerous faults in California. Although it gets less attention than the San Andreas fault, which crosses the city of San Francisco (and extends well into Southern California), the Hayward fault is near population centers in Fremont, Oakland and dozens of other cities.
-- Ken Schwencke and Shelby Grad
Credit: U.S. Geological Survey website