M3.8 earthquake 37 km SSW of Ferndale, California

A magnitude 3.8 earthquake struck 37 km SSW of Ferndale, California on Sat, Apr 13, 1985, 7:05 AM PST (15:05 UTC), 15 km (10 mi) below the surface.

A larger quake followed: M4.3 104 km W of Ferndale, California. This one was a foreshock.

Map

Where this earthquake was located, with the others nearby. Select one for its page.

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
3.8	ML, local (Richter)	Northern California Seismic System	Preferred · Final · 0 stations
3.8	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed

The USGS’s account of the effects of this earthquake.

Felt at Ferndale.

From the USGS event page for nc46043. U.S. Geological Survey text and figures are in the public domain.

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: 50 in the 60 days after this one and 35 in the 30 days before it.

From the USGS Earthquake Hazards Program and its partner networks, event nc46043 (also filed as usp0002dsc). Read Thu, Oct 1, 2026, 9:22 PM UTC.