Alaska earthquakes

M1.5 earthquake 265 km W of Adak, Alaska

A magnitude 1.5 earthquake struck 265 km W of Adak, Alaska on Fri, Aug 13, 2021, 1:40 AM GMT+12 (13:40 UTC), 20 km (12 mi) below the surface.

A larger quake followed: M4.8 Rat Islands, Aleutian Islands, Alaska. This one was a foreshock.

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The earthquake

Magnitude
1.5 (ml), micro
Local time
UTC
2021-08-12 13:40:21 UTC
Depth
19.8 km (12.3 mi), shallow
Epicenter
51.861° N, 179.506° E
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 2.0 km horizontally, 1.1 km in depth
Magnitude uncertainty
±0.31
Depth from
From location
Station coverage gap
289°, poorly surrounded by stations
Stations used
6

Nearby

Within 100 km, magnitude 1.5 and up: 107 in the 60 days after this one and 75 in the 30 days before it.

After

The first 60 of 107.

Before

Earthquakes todayAlaska earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event av91337041. Read Thu, Sep 24, 2026, 12:07 PM UTC.