M2.5 earthquake 10 km W of Philo, California

A magnitude 2.5 earthquake struck 10 km W of Philo, California on Wed, May 19, 1976, 5:03 AM PDT (12:03 UTC), 2 km (1 mi) below the surface.

A larger quake followed: M3.0 10 km ENE of Healdsburg, California. 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: 63 in the 60 days after this one and 34 in the 30 days before it.

The first 60 of 63.

From the USGS Earthquake Hazards Program and its partner networks, event nc1029744. Read Wed, Sep 30, 2026, 12:55 PM UTC.