Alaska earthquakes

M3.3 earthquake 95 km W of Adak, Alaska

A magnitude 3.3 earthquake struck 95 km W of Adak, Alaska on Thu, Apr 20, 2023, 9:58 PM HADT (06:58 UTC), 5 km (3 mi) below the surface.

A larger quake followed: M5.3 135 km WSW of Adak, Alaska. This one was a foreshock.

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The earthquake

Magnitude: 3.3 (ml), minor
Local time: Thu, Apr 20, 2023, 9:58 PM HADT
UTC: 2023-04-21 06:58:55 UTC
Depth: 5.0 km (3.1 mi), shallow
Epicenter: 51.827° N, 178.017° 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 1.3 km horizontally, 1.5 km in depth
Magnitude uncertainty: ±0.10
Depth from: Operator assigned
Station coverage gap: 145°
Stations used: 20

Nearby

Within 100 km, magnitude 1.5 and up: at least 200 in the 60 days after this one and at least 200 in the 30 days before it.

After

The first 60 of at least 200.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000k668 (also filed as av91856581, ak02353okoc6). Read Wed, Sep 30, 2026, 11:34 AM UTC.