M2.7 earthquake 55 km NNW of Atka, Alaska

A magnitude 2.7 earthquake struck 55 km NNW of Atka, Alaska on Wed, Apr 20, 2022, 11:53 PM HADT (08:53 UTC), 171 km (106 mi) below the surface.

A larger quake followed: M4.5 62 km NNW of Atka, Alaska. This one was a foreshock.

Map

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

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
2.7	ML, local (Richter)	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.128 · 8 stations
2.6	ML, local (Richter)	Alaska Earthquake Center	Preliminary

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Within 100 km, magnitude 1.5 and up: 89 in the 60 days after this one and 39 in the 30 days before it.

The first 60 of 89.

From the USGS Earthquake Hazards Program and its partner networks, event us7000hh4c (also filed as ak02253pqegg). Read Sun, Oct 4, 2026, 8:08 PM UTC.