A 3.1-magnitude earthquake jolted the San Ramon Valley Tuesday morning, according to the U.S. Geological Survey. The epicenter was 2.8 miles southeast of San Ramon on the Calaveras

The clusters of earthquakes have all been underneath the East Bay suburb of San Ramon, which is close to the Calaveras fault. There were at least 19 earthquakes of magnitude 2 or greater on Monday alone.

A preliminary 3.1 magnitude earthquake struck Tuesday morning near San Ramon, according to the United States Geological Survey. The temblor was reported at 5:53 a.m. and centered 2.8 miles southeast of San Ramon,

A swarm of at least six earthquakes reaching up to magnitude 2.9 rattled San Ramon near San Francisco, the U.S. Geological Survey reports.