Alaska earthquakes

M4.3 earthquake 120 km WNW of Adak, Alaska

A magnitude 4.3 earthquake struck 120 km WNW of Adak, Alaska on Thu, Jul 23, 2020, 1:08 PM HADT (22:08 UTC), 234 km (145 mi) below the surface.

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

Map

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

Open the live map with earthquakes

The earthquake

Magnitude: 4.3 (mb), light
Local time: Thu, Jul 23, 2020, 1:08 PM HADT
UTC: 2020-07-23 22:08:40 UTC
Depth: 234.1 km (145.4 mi), intermediate-depth
Epicenter: 52.420° N, 178.155° 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 9.3 km horizontally, 7.9 km in depth
Magnitude uncertainty: ±0.05
Depth from: From location
Station coverage gap: 105°
Stations used: 138

Nearby

Within 100 km, magnitude 1.5 and up: 58 in the 60 days after this one and 32 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 us6000b31i (also filed as ak0209febhbj). Read Tue, Sep 29, 2026, 2:19 AM UTC.