M5.1 earthquake 40 km E of Adak, Alaska

A magnitude 5.1 earthquake struck 40 km E of Adak, Alaska on Sun, Feb 1, 2026, 2:43 AM HAST (12:43 UTC), 62 km (38 mi) below the surface.

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
5.1	mb, body-wave	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.028 · 398 stations
5.2	ML, local (Richter)	Alaska Earthquake Center	Reviewed · ±0.3 · 37 stations

The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.

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

Reviewed by a seismologist.

Within 100 km, magnitude 2.1 and up: 94 in the 60 days after this one and 65 in the 30 days before it.

The first 60 of 94.

From the USGS Earthquake Hazards Program and its partner networks, event us6000s5ul (also filed as ak2026cfwuww). Read Thu, Oct 1, 2026, 8:10 PM UTC.