Alaska earthquakes

M3.1 earthquake 20 km SE of Unalaska, Alaska

A magnitude 3.1 earthquake struck 20 km SE of Unalaska, Alaska on Thu, Jul 31, 2025, 3:56 AM AKDT (11:56 UTC), 71 km (44 mi) below the surface.

A larger quake followed: M4.4 26 km W of Akutan, Alaska. This one was a foreshock.

Unalaska forecast More in Alaska

Map

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

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The earthquake

Magnitude: 3.1 (ml), minor
Local time: Thu, Jul 31, 2025, 3:56 AM AKDT
UTC: 2025-07-31 11:56:31 UTC
Depth: 71.2 km (44.3 mi), intermediate-depth
Epicenter: 53.725° N, 166.339° 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 9.0 km horizontally, 8.7 km in depth
Magnitude uncertainty: ±0.10
Depth from: From location
Station coverage gap: 172°
Stations used: 22

Nearest places

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

Unalaska, AlaskaPopulation 4,491. Forecast21 kmSE

Nearby

Within 100 km, magnitude 1.5 and up: 72 in the 60 days after this one and 79 in the 30 days before it.

After

The first 60 of 72.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000rcep (also filed as ak0259qstewn). Read Wed, Sep 30, 2026, 10:34 AM UTC.