Alaska earthquakes

M3.2 earthquake 24 km SSW of Adak, Alaska

A magnitude 3.2 earthquake struck 24 km SSW of Adak, Alaska on Fri, Sep 17, 2021, 12:40 PM HADT (21:40 UTC), 77 km (48 mi) below the surface.

A larger quake followed: M3.8 37 km ENE of Adak, Alaska. This one was a foreshock.

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The earthquake

Magnitude
3.2 (ml), minor
Local time
UTC
2021-09-17 21:40:32 UTC
Depth
77.2 km (48.0 mi), intermediate-depth
Epicenter
51.656° N, 176.714° 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 6.2 km horizontally, 7.2 km in depth
Magnitude uncertainty
±0.15
Depth from
From location
Station coverage gap
211°, poorly surrounded by stations
Stations used
19

Nearby

Within 100 km, magnitude 1.5 and up: 133 in the 60 days after this one and 66 in the 30 days before it.

After

The first 60 of 133.

Before

Earthquakes todayAlaska earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000fudk (also filed as ak021bycgzal). Read Thu, Sep 24, 2026, 7:04 AM UTC.