A 3.1 magnitude quake struck near San Ramon early Tuesday, part of a recent East Bay swarm. No damage reported, but experts urge preparedness.

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.

People in the Bay Area continue to experience the “flare up” of earthquakes into Monday afternoon, Oakland being the latest city to experience a jolt.

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 magnitude of 2.9 is classified as a micro earthquake, which typically goes unnoticed by most people. However, even minor quakes can provide critical data for scientists studying seismic patterns. For instance,