Alaska earthquakes

M3.9 earthquake 251 km SW of Adak, Alaska

A magnitude 3.9 earthquake struck 251 km SW of Adak, Alaska on Fri, Dec 25, 2020, 7:52 AM HAST (17:52 UTC), 10 km (6 mi) below the surface.

A larger quake followed: M5.6 209 km WSW of Adak, Alaska. This one was a foreshock.

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The earthquake

Magnitude: 3.9 (mb), minor
Local time: Fri, Dec 25, 2020, 7:52 AM HAST
UTC: 2020-12-25 17:52:42 UTC
Depth: 10.0 km (6.2 mi), shallow
Epicenter: 50.131° N, 178.906° W
Region: Alaska
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 4.5 km horizontally, 1.9 km in depth
Magnitude uncertainty: ±0.09
Depth from: Operator assigned
Station coverage gap: 136°
Stations used: 76

Nearby

Within 100 km, magnitude 1.5 and up: 22 in the 60 days after this one and 4 in the 30 days before it.

After

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000d30a (also filed as ak020gjnwk5r). Read Sat, Sep 26, 2026, 6:03 PM UTC.