Alaska earthquakes

M4.2 earthquake 168 km WNW of Adak, Alaska

A magnitude 4.2 earthquake struck 168 km WNW of Adak, Alaska on Fri, Oct 23, 2020, 7:01 PM HADT (04:01 UTC), 205 km (127 mi) below the surface.

A larger quake followed: M4.3 156 km WSW of Adak, Alaska. This one was a foreshock.

Map

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The earthquake

Magnitude: 4.2 (mb), light
Local time: Fri, Oct 23, 2020, 7:01 PM HADT
UTC: 2020-10-24 04:01:05 UTC
Depth: 204.8 km (127.3 mi), intermediate-depth
Epicenter: 52.313° N, 178.990° 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 8.7 km horizontally, 6.1 km in depth
Magnitude uncertainty: ±0.05
Depth from: From location
Station coverage gap: 47°
Stations used: 95

Nearby

Within 100 km, magnitude 1.5 and up: 30 in the 60 days after this one and 23 in the 30 days before it.

After

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000ccf3 (also filed as ak020dowjdnw). Read Sun, Sep 27, 2026, 6:42 AM UTC.