California earthquakes

M2.3 earthquake 6 km SW of Cromberg, California

A magnitude 2.3 earthquake struck 6 km SW of Cromberg, California on Fri, Apr 3, 1987, 4:46 AM PST (12:46 UTC), -2 km (-1 mi) below the surface.

A larger quake followed: M3.4 1 km S of Lake Almanor Country Club, California. This one was a foreshock.

Graeagle forecast More in California

Map

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

Open the live map with earthquakes

The earthquake

Magnitude: 2.3 (Md, duration), micro
Magnitude from: Northern California Seismic System
Local time: Fri, Apr 3, 1987, 4:46 AM PST
UTC: 1987-04-03 12:46:57 UTC
Depth: -1.9 km (-1.2 mi), shallow
Epicenter: 39.816° N, 120.740° W
Region: California
Tsunami flag: No
Status: Reviewed by a seismologist

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

Reviewed by a seismologist.

Location uncertainty: About 0.4 km horizontally, 3.1 km in depth
Magnitude uncertainty: ±0.18
Depth from: From location
Station coverage gap: 91°
Stations used: 20

Nearest places

Distance and direction from each place to the epicenter, with its forecast.

Nearby

Within 100 km, magnitude 1.5 and up: 21 in the 60 days after this one and 12 in the 30 days before it.

After

Before

Earthquakes today California earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc97922. Read Sat, Oct 3, 2026, 3:48 PM UTC.