Alaska earthquakes

M3.8 earthquake 75 km SE of Adak, Alaska

A magnitude 3.8 earthquake struck 75 km SE of Adak, Alaska on Tue, Sep 15, 2020, 3:51 PM HADT (00:51 UTC), 26 km (16 mi) below the surface.

A larger quake followed: M5.3 76 km SW of Atka, Alaska. This one was a foreshock.

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Where this earthquake was located, with the others nearby. Select one for its page.

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The earthquake

Magnitude
3.8 (mb), minor
Local time
UTC
2020-09-16 00:51:47 UTC
Depth
25.8 km (16.1 mi), shallow
Epicenter
51.327° N, 175.999° W
Region
Alaska
Felt reports
1
Tsunami flag
No
Status
Reviewed by a seismologist

Did you feel it?

1 person reported to the USGS what they felt; the strongest reported shaking was II, weak shaking.

Did You Feel It? map: shaking reported by the public
Shaking reported by the public, by area. Map: USGS Did You Feel It?

How well it is located

Reviewed by a seismologist.

Location uncertainty
About 4.9 km horizontally, 10.3 km in depth
Magnitude uncertainty
±0.12
Depth from
From location
Station coverage gap
217°, poorly surrounded by stations
Stations used
56

Nearby

Within 100 km, magnitude 1.5 and up: 125 in the 60 days after this one and 73 in the 30 days before it.

After

The first 60 of 125.

Before

Earthquakes todayAlaska earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us7000bp69 (also filed as ak020by019qa). Read Tue, Sep 29, 2026, 1:39 AM UTC.