Another East Bay Earthquake Added to Slowing Swarm of Shakers

Since the swarm began about three weeks ago, around 540 earthquakes have been recorded in the area.

A small earthquake was reported by the U.S. Geological Survey this afternoon in San Ramon, adding yet another temblor to the area’s earthquake swarm as it appears to be winding down. The magnitude 3.1 earthquake was reported at 2:54 p.m. today by the USGS. But the earthquake, which had a depth of more than 5 miles, wasn’t much of a shaker.

Employees at a post office and a business right in the middle of where USGS reported the earthquake said they didn’t feel anything. An operator at the nearby San Ramon Regional Medical Center did attest to minor shaking, and there were a number of San Ramon residents who reported feeling shaking to USGS. Today’s temblor follows two consecutive earthquakes of about the same size that were reported at 11:32 p.m. and then 11:38 p.m. on Saturday, according to the USGS.

“(But) after a slight pickup in activity on Saturday, seismic activity under San Ramon has been low,” USGS officials said in a post on their website. Prior to today’s magnitude 3.1 earthquake, there had only been one earthquake of any size reported in the area in the past 24 hours.

Since the swarm began about three weeks ago, the Northern California Seismic Network has detected around 540 earthquakes in this area, including more than 90 with a magnitude of 2.0 or greater. “The earthquake swarm may continue for an additional week or more, and we expect similar fluctuations in seismic activity as we have seen over the past week,” USGS officials said.

No injuries or damage have been reported as a result of the quake.

By AUTUMN JOHNSON (Patch Staff)


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