Alaska earthquakes

M3.8 earthquake 97 km SW of Adak, Alaska

A magnitude 3.8 earthquake struck 97 km SW of Adak, Alaska on Thu, Apr 16, 2020, 9:04 AM HADT (18:04 UTC), 35 km (22 mi) below the surface.

A larger quake followed: M5.0 141 km WSW of Adak, Alaska. This one was a foreshock.

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The earthquake

Magnitude
3.8 (mb), minor
Local time
UTC
2020-04-16 18:04:11 UTC
Depth
35.0 km (21.7 mi), shallow
Epicenter
51.275° N, 177.667° 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 5.1 km horizontally, 1.9 km in depth
Magnitude uncertainty
±0.06
Depth from
Operator assigned
Station coverage gap
141°
Stations used
80

Nearby

Within 100 km, magnitude 1.5 and up: at least 200 in the 60 days after this one and 96 in the 30 days before it.

After

The first 60 of at least 200.

Before

Earthquakes todayAlaska earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us70008xrc (also filed as ak0204x98tg7). Read Wed, Sep 30, 2026, 7:19 PM UTC.