SAN FRANCISCO (CBS SF) – The USGS reports an earthquake with a preliminary magnitude 3.4 struck east of San Ramon Wednesday morning.
The quake along Calaveras fault struck at a depth of 6.8 miles at 9:30 a.m. The tremor hit the same area as a slightly smaller earthquake Tuesday afternoon.
USGS spokeswoman Leslie Gordon said the quake caused “weak to light shaking” in the area that could also be felt in other neighboring cities.
San Ramon Police said there have been no initial reports of damage or injuries.
Gordon said it was at least the fourth small quake to strike the region since Monday. This includes three small quakes on Tuesday, the one in San Ramon and two more near Broadmoor.
The USGS says the Danville-San Ramon corridor is one of the most seismically active parts of the Bay Area. In addition to the Calaveras fault, several smaller faults branch out around the area.
“Right now we’ve only had six (recent) earthquakes, we don’t know if they’ll continue, or if today’s 3.4 was the last one. If they do we’ll probably refer to it as a swarm, but for now it’s just a series of small earthquakes in a seismically active area,” said Dr. David Schwartz of the USGS.
There is no way to tell if the quakes mean a larger one is more or less likely for the region.
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