Alaska earthquakes

M1.6 earthquake 91 km SW of Adak, Alaska

A magnitude 1.6 earthquake struck 91 km SW of Adak, Alaska on Wed, Apr 28, 2021, 3:40 AM HADT (12:40 UTC), 18 km (11 mi) below the surface.

Automatic solution: the magnitude and location may still be revised.

A larger quake followed: M4.2 122 km WSW of Adak, Alaska. This one was a foreshock.

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The earthquake

Magnitude
1.6 (ml), micro
Local time
UTC
2021-04-28 12:40:16 UTC
Depth
17.9 km (11.1 mi), shallow
Epicenter
51.396° N, 177.712° W
Region
Alaska
Tsunami flag
No
Status
Automatic solution, may be revised

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

An automatic solution; a seismologist may revise it.

Stations used
23

Nearby

Within 100 km, magnitude 1.5 and up: 64 in the 60 days after this one and 75 in the 30 days before it.

After

The first 60 of 64.

Before

Earthquakes todayAlaska earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event ak0215fcsrew. Read Thu, Sep 24, 2026, 12:47 PM UTC.