Alaska earthquakes

M3.6 earthquake 38 km WSW of Atka, Alaska

A magnitude 3.6 earthquake struck 38 km WSW of Atka, Alaska on Tue, Apr 21, 2020, 2:10 AM HADT (11:10 UTC), 82 km (51 mi) below the surface.

A larger quake followed: M4.0 100 km SW of Atka, Alaska. This one was a foreshock.

Map

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

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The earthquake

Magnitude: 3.6 (mb), minor
Local time: Tue, Apr 21, 2020, 2:10 AM HADT
UTC: 2020-04-21 11:10:21 UTC
Depth: 82.1 km (51.0 mi), intermediate-depth
Epicenter: 52.053° N, 174.712° 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 7.8 km horizontally, 6.6 km in depth
Magnitude uncertainty: ±0.18
Depth from: From location
Station coverage gap: 176°
Stations used: 34

Nearby

Within 100 km, magnitude 1.5 and up: 109 in the 60 days after this one and 55 in the 30 days before it.

After

The first 60 of 109.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us60009dbm (also filed as ak02055estuv). Read Tue, Sep 29, 2026, 10:07 PM UTC.