A series of mostly smaller quakes that awakened San Ramon residents on Monday continued to rattle the area by late morning, and some Piedmont residents also felt shaking.
Monday’s quake swarm began with a 3.8 shaker at 6:27 a.m. Since then, two dozen quakes above 2.5 magnitude were recorded in the area — the largest a 4.2 jolt just after 7 a.m., according to the U.S. Geological Survey.
Another 22 quakes below 2.5 were recorded in the area on Monday morning, the USGS said.
The quakes were centered near the northern section of the Calaveras Fault in the neighborhood near the intersection of Alcosta Boulevard and Bollinger Canyon Road, according to an interactive map published by the UC Berkeley Seismology Lab.
The temblors were also felt in nearby cities, including Dublin, Danville and Pleasanton. There were no immediate reports of injuries or significant damage.
A number of small earthquakes of 4.0 or lower have been recorded since early November 2025 in the San Ramon area.
A version of this post, Shake, rattle and roll: Ongoing quake swarm near San Ramon continues to jangle nerves, appeared first on Local News Matters.