Earthquake swarm hits San Francisco Bay area with back-to-back tremors

An earthquake swarm hit the San Francisco Bay Area on Sunday morning.

The cluster of up to eight quakes, ranging from 2.5 to 3.8 on the Richter scale, first occurred from 9:38am to 9:41am around southeast of San Ramon.

The last quake hit at 10:42am, less than a mile west of San Ramon. 

Residents in Emeryville, Dublin and San Ramon reported feeling jolts. 

“Felt a lot stronger than 3.7! I was guessing at least a 5. Strong jolt and rumble,” said an X user, claiming to be from San Ramon. 

Earthquakes above a 2.5 can usually be felt, but usually only cause minor damage to buildings, according Michigan Tech University’s earthquake magnitude scale. 

No damage has been reported. 

The swarm of quakes hit about 25 to 30 miles east of San Francisco. 

One smaller quake had an epicenter south of Patterson, 50 miles away from the rest of the cluster. 

Southern California is prone to seismic activity due to the San Andreas Fault — a boundary between two shifting tectonic plates that often generates earthquakes. 

In August, there was a swarm of 100 earthquakes  roughly 90 miles north of San Francisco, with the strongest reaching a 4.0 magnitude. No damage was reported. 

A major earthquake is expected to hit California before 2032, according to modelling done by the USGS.