M1.6 earthquake 26km NE of Thermal, CA

A magnitude 1.6 earthquake struck 26km NE of Thermal, CA on Tue, Aug 4, 1981, 7:28 PM PDT (02:28 UTC), 0 km (0 mi) below the surface.

A larger quake followed: M4.0 8km NE of Julian, 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: 192 in the 60 days after this one and 103 in the 30 days before it.

The first 60 of 192.

From the USGS Earthquake Hazards Program and its partner networks, event ci520536. Read Fri, Oct 2, 2026, 10:23 AM UTC.