Alaska earthquakes

M2.5 earthquake 158 km WSW of Adak, Alaska

A magnitude 2.5 earthquake struck 158 km WSW of Adak, Alaska on Tue, Apr 21, 2020, 1:42 PM HADT (22:42 UTC), 10 km (6 mi) below the surface.

A larger quake followed: M5.2 186 km WSW of Adak, 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: 2.5 (ml), micro
Local time: Tue, Apr 21, 2020, 1:42 PM HADT
UTC: 2020-04-21 22:42:17 UTC
Depth: 10.0 km (6.2 mi), shallow
Epicenter: 51.356° N, 178.761° 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 1.0 km horizontally, 1.7 km in depth
Magnitude uncertainty: ±0.15
Depth from: Operator assigned
Station coverage gap: 202°, poorly surrounded by stations
Stations used: 42

Nearby

Within 100 km, magnitude 1.5 and up: 178 in the 60 days after this one and 106 in the 30 days before it.

After

The first 60 of 178.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us70009ga4 (also filed as ak02055ljfl7). Read Wed, Sep 30, 2026, 11:25 PM UTC.