Friday Morning Quake Strikes East Bay: Did You Feel It?

SAN RAMON, CA — A 2.8-magnitude earthquake struck San Ramon at 5:25 a.m. Friday morning, according to the U.S. Geological Survey.

The quake had a depth of 7.5 km and was centered just west of Alcosta Boulevard and south of Montevideo Drive, close to California High School, according to USGS. Many around the Tri-Valley reported feeling weak to light shaking, according to USGS's "Did You Feel It?" map.

San Ramon has been the center of hundreds of earthquake swarms since November, most recently a 2.6 on Sunday, March 8.

The city sits along the Calaveras Fault, and several micro-faults along the main fault result in swarms of quakes. When fluids like water or gas move through a complex web of cracks in tiny faults, this can trigger many dozens of small quakes in quick succession.

On Feb. 27, the city of San Ramon hosted a Q&A with local mayors, Supervisor Candace Andersen, SRVFPD Chief Jonas Aguiar, and UC Berkeley seismologist Dr. Angie Lux.

SEE ALSO:

• Why Does San Ramon Get So Many Earthquakes?
• 2 Late Night Quakes Strike East Bay
• San Ramon To Host Earthquake Swarm Q&A With Seismologist, Fire Chief, Mayors
• San Ramon Details Earthquake Readiness Policies
• How Prepared Are You For An Earthquake? 10 Things You Need