A small earthquake shook the East Bay early Sunday, prompting BART to bring trains to a stop for a few minutes to check for damage.
The U.S. Geological Survey initially recorded it as a 3.9 magnitude quake when it struck AT 8:49 a.m. but bumped it down to 3.7 minutes later and to 3.5 in the afternoon.
Preliminary data show the origin about nine miles below ground in Concord, with people reportedly feeling it in Oakland, Berkeley, Vallejo, and the eastern edge of San Francisco.
A revised USGS report cited the epicenter as closer to Pleasant Hill, with reports of it felt as far south as Santa Cruz and as far north as Roseville.
The shake came just two days after San Francisco woke to a series of three small quakes.
The first one early Friday — another 3.7 magnitude — originated just off the coast by the S.F. Zoo (apparently around the epicenter of the devastating 1906 quake) and was followed that morning by two below-3.0-magnitude aftershocks.