M4.0 earthquake 65 km SSW of Adak, Alaska

A magnitude 4.0 earthquake struck 65 km SSW of Adak, Alaska on Sun, Nov 23, 2025, 12:44 AM HAST (10:44 UTC), 35 km (22 mi) below the surface.

A larger quake followed: M4.9 57 km SSE of Adak, 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
4.0	mb, body-wave	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.043 · 149 stations
4.5	ML, local (Richter)	Alaska Earthquake Center	Reviewed · ±0.3 · 35 stations

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

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Within 100 km, magnitude 1.5 and up: 151 in the 60 days after this one and 28 in the 30 days before it.

The first 60 of 151.

From the USGS Earthquake Hazards Program and its partner networks, event us6000rpxu (also filed as ak2025xbgbyk). Read Sat, Oct 3, 2026, 9:35 PM UTC.