M1.7 earthquake 20km ESE of Anza, CA

A magnitude 1.7 earthquake struck 20km ESE of Anza, CA on Thu, Apr 12, 1984, 10:32 PM PST (06:32 UTC), 12 km (8 mi) below the surface.

A larger quake followed: M1.8 10km SW of Morongo Valley, 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: 189 in the 60 days after this one and 0 in the 30 days before it.

The first 60 of 189.

From the USGS Earthquake Hazards Program and its partner networks, event ci36601. Read Tue, Sep 22, 2026, 9:36 PM UTC.