More small quakes shake Contra Costa County
Feb. 23, 2018
DANVILLE, Calif. (AP) — Several more small earthquakes have occurred east of San Francisco Bay in the Danville area of Contra Costa County where a swarm has been occurring.
The largest so far early Friday was a magnitude-3.3 tremor at 5:28 a.m. at a depth of 5 miles (8 kilometers), west-southwest of Diablo.
Brian Kilgore of the U.S. Geological Survey told NBC Bay Area this week there's no evidence that swarms indicate a large quake is coming. Kilgore says large earthquakes have not followed swarms in previous years.