Alaska earthquakes

M2.5 earthquake 129 km S of Unalaska, Alaska

A magnitude 2.5 earthquake struck 129 km S of Unalaska, Alaska on Wed, Sep 20, 2023, 4:04 PM AKDT (00:04 UTC), 10 km (6 mi) below the surface.

A larger quake followed: M4.3 96 km S of Unalaska, 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: 2.5 (ml), micro
Local time: Wed, Sep 20, 2023, 4:04 PM AKDT
UTC: 2023-09-21 00:04:56 UTC
Depth: 10.0 km (6.2 mi), shallow
Epicenter: 52.715° N, 166.650° 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 3.9 km horizontally, 2.0 km in depth
Magnitude uncertainty: ±0.15
Depth from: Operator assigned
Station coverage gap: 261°, poorly surrounded by stations
Stations used: 14

Nearest places

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

Unalaska, AlaskaPopulation 4,491. Forecast129 kmS

Nearby

Within 100 km, magnitude 1.5 and up: 76 in the 60 days after this one and 51 in the 30 days before it.

After

The first 60 of 76.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000lcuh (also filed as ak023c4lwlr4). Read Mon, Sep 28, 2026, 5:55 PM UTC.