M1.6 earthquake 5 km SW of Cobb, California

A magnitude 1.6 earthquake struck 5 km SW of Cobb, California on Fri, Dec 16, 1983, 3:01 PM PST (23:01 UTC), 0 km (0 mi) below the surface.

A larger quake followed: M2.0 6 km SW of Glen Ellen, California. This one was a foreshock.

Map

Where this earthquake was located, with the others nearby. Select one for its page.

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Distance and direction from each place to the epicenter, with its forecast.

Within 100 km, magnitude 1.5 and up: 164 in the 60 days after this one and 0 in the 30 days before it.

The first 60 of 164.

From the USGS Earthquake Hazards Program and its partner networks, event nc1108570. Read Tue, Sep 22, 2026, 7:23 AM UTC.