M3.1 earthquake 23km ESE of Anza, CA

A magnitude 3.1 earthquake struck 23km ESE of Anza, CA on Mon, Feb 1, 1982, 9:40 PM PST (05:40 UTC), 5 km (3 mi) below the surface.

A larger quake followed: M4.5 12km SSW of Ocotillo Wells, CA. This one was a foreshock.

Map

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

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
3.09	ML, local (Richter)	Southern California Seismic Network	Preferred · Final · 8 stations
3.2	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed

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: 191 in the 60 days after this one and 98 in the 30 days before it.

The first 60 of 191.

From the USGS Earthquake Hazards Program and its partner networks, event ci105305 (also filed as usp0001jeq). Read Fri, Oct 2, 2026, 5:33 PM UTC.