M1.6 earthquake 4 km ESE of Philo, California

A magnitude 1.6 earthquake struck 4 km ESE of Philo, California on Wed, Feb 25, 1987, 1:56 PM PST (21:56 UTC), 6 km (4 mi) below the surface.

A larger quake followed: M2.4 16 km NE of Upper Lake, 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: 172 in the 60 days after this one and 0 in the 30 days before it.

The first 60 of 172.

From the USGS Earthquake Hazards Program and its partner networks, event nc1147679. Read Tue, Sep 22, 2026, 4:12 PM UTC.