M2.3 earthquake 11km SE of Anza, CA

A magnitude 2.3 earthquake struck 11km SE of Anza, CA on Wed, Oct 11, 1978, 4:10 PM PDT (23:10 UTC), 5 km (3 mi) below the surface.

A larger quake followed: M4.3 12km SSW of Big Bear Lake, CA. 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: 173 in the 60 days after this one and 171 in the 30 days before it.

The first 60 of 173.

From the USGS Earthquake Hazards Program and its partner networks, event ci3313700. Read Mon, Oct 5, 2026, 9:41 AM UTC.