California earthquakes

M4.0 earthquake 10 km SW of Huron, California

A magnitude 4.0 earthquake struck 10 km SW of Huron, California on Sun, May 22, 1983, 1:39 AM PDT (08:39 UTC), 12 km (7 mi) below the surface.

A larger quake followed: M4.7 12 km NNW of Coalinga, California. This one was a foreshock.

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Map

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

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The earthquake

Magnitude
4.0 (Md, duration), light
Magnitude from
Northern California Seismic System
Local time
UTC
1983-05-22 08:39:21 UTC
Depth
11.8 km (7.3 mi), shallow
Epicenter
36.148° N, 120.202° W
Tsunami flag
No
Status
Reviewed by a seismologist

Magnitude estimates

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.ScaleComputed byNotes
4.04Md, durationNorthern California Seismic SystemPreferred · Final · ±0.19 · 22 stations
4.2mb, body-waveUSGS National Earthquake Information CenterReviewed · 5 stations
3.88ML, local (Richter)Southern California Seismic NetworkFinal · ±0.049 · 11 stations

What happened

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

Felt in the Coalinga area.

From the USGS event page for nc1095152. U.S. Geological Survey text and figures are in the public domain.

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 0.2 km horizontally, 0.3 km in depth
Magnitude uncertainty
±0.19
Depth from
From location
Station coverage gap
60°
Stations used
65

Nearest places

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

Nearby

Within 100 km, magnitude 1.5 and up: 199 in the 60 days after this one and 194 in the 30 days before it.

After

The first 60 of 199.

Before

Earthquakes todayCalifornia earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc1095152 (also filed as usp0001vjm, ci3355455). Read Thu, Oct 1, 2026, 6:48 AM UTC.