M1.5 earthquake 21km ESE of Anza, CA

A magnitude 1.5 earthquake struck 21km ESE of Anza, CA on Thu, Aug 15, 1985, 1:59 AM PDT (08:59 UTC), 11 km (7 mi) below the surface.

A larger quake followed: M4.6 3km SSE of Loma Linda, 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: 186 in the 60 days after this one and 188 in the 30 days before it.

The first 60 of 186.

From the USGS Earthquake Hazards Program and its partner networks, event ci109640. Read Sat, Oct 3, 2026, 2:18 PM UTC.