California earthquakes

M2.4 earthquake 21km SSE of Mineral, CA

A magnitude 2.4 earthquake struck 21km SSE of Mineral, CA on Wed, Dec 22, 2021, 3:50 AM PST (11:50 UTC), 15 km (9 mi) below the surface.

A larger quake followed: M2.9 12km SE of Mineral, CA. 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
2.4 (Md, duration), micro
Magnitude from
Northern California Seismic System
Local time
UTC
2021-12-22 11:50:04 UTC
Depth
14.8 km (9.2 mi), shallow
Epicenter
40.172° N, 121.491° W
Felt reports
2
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
2.43Md, durationNorthern California Seismic SystemPreferred · Final · ±0.198 · 25 stations
2.0ML, local (Richter)Nevada Seismological LaboratoryReviewed · ±0.17 · 6 stations

Did you feel it?

2 people reported to the USGS what they felt; the strongest reported shaking was III, weak shaking.

Did You Feel It? map: shaking reported by the public
Shaking reported by the public, by area. Map: USGS Did You Feel It?

How well it is located

Reviewed by a seismologist.

Location uncertainty
About 0.5 km horizontally, 0.8 km in depth
Magnitude uncertainty
±0.20
Depth from
From location
Station coverage gap
73°
Stations used
28

Nearest places

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

Nearby

Within 100 km, magnitude 1.5 and up: 28 in the 60 days after this one and 18 in the 30 days before it.

After

Before

Earthquakes todayCalifornia earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc73667621 (also filed as nn00830359). Read Sun, Oct 4, 2026, 7:48 PM UTC.