Alaska earthquakes

M3.8 earthquake 79 km SW of Adak, Alaska

A magnitude 3.8 earthquake struck 79 km SW of Adak, Alaska on Fri, Jul 17, 2020, 12:38 PM HADT (21:38 UTC), 32 km (20 mi) below the surface.

A larger quake followed: M4.6 125 km W of Adak, Alaska. This one was a foreshock.

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The earthquake

Magnitude
3.8 (ml), minor
Local time
UTC
2020-07-17 21:38:24 UTC
Depth
31.8 km (19.8 mi), shallow
Epicenter
51.379° N, 177.459° 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 4.5 km horizontally, 9.5 km in depth
Magnitude uncertainty
±0.12
Depth from
From location
Station coverage gap
205°, poorly surrounded by stations
Stations used
34

Nearby

Within 100 km, magnitude 1.5 and up: at least 199 in the 60 days after this one and 111 in the 30 days before it.

After

The first 60 of at least 199.

Before

Earthquakes todayAlaska earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000b7bb (also filed as ak02095gocwv). Read Tue, Sep 29, 2026, 7:40 AM UTC.