California earthquakes

M5.6 earthquake 8 km SW of Huron, California

A magnitude 5.6 earthquake struck 8 km SW of Huron, California on Sun, Aug 4, 1985, 5:01 AM PDT (12:01 UTC), 16 km (10 mi) below the surface.

Huron 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: 5.6 (ml), moderate
Local time: Sun, Aug 4, 1985, 5:01 AM PDT
UTC: 1985-08-04 12:01:55 UTC
Depth: 15.9 km (9.9 mi), shallow
Epicenter: 36.143° N, 120.156° W
Region: California
Strongest shaking: VII, very strong shaking
Tsunami flag: No
Status: Reviewed by a seismologist

Shaking

The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.

Strongest estimated: VII, very strong shaking
Peak ground acceleration: 24.1% of gravity
Peak ground velocity: 2.8 cm/s
Map: Automatic

USGS ShakeMap: estimated shaking intensity around the epicenter — Estimated shaking intensity. Map: USGS ShakeMap.

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 0.3 km horizontally, 0.6 km in depth
Depth from: From location
Station coverage gap: 163°
Stations used: 45

Nearest places

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

Nearby

Within 100 km, magnitude 2.5 and up: 92 in the 60 days after this one and 10 in the 30 days before it.

After

The first 60 of 92.

Before

Earthquakes today California earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc52348 (also filed as gcmtb080485c, ushis3895, usp0002hc7, iscgem517307, ci69717, atlas19850804120158). Read Tue, Sep 22, 2026, 3:49 PM UTC.