M5.0 earthquake 104 km SSW of Adak, Alaska

A magnitude 5.0 earthquake struck 104 km SSW of Adak, Alaska on Wed, Feb 28, 2024, 11:22 PM HAST (09:22 UTC), 27 km (17 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
5.0	Mww, W-phase moment	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.069 · 20 stations
5.0	Mww, W-phase moment	Alaska Earthquake Center	Preliminary
5.0	Mwr, regional moment	USGS National Earthquake Information Center	Moment tensor · Reviewed

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.

How the rock slipped, from the moment tensor, and the USGS estimate of landslides and liquefaction.

Reviewed by a seismologist.

Within 100 km, magnitude 2.0 and up: 180 in the 60 days after this one and 57 in the 30 days before it.

The first 60 of 180.

From the USGS Earthquake Hazards Program and its partner networks, event us6000mfsl (also filed as ak0242rdqhho). Read Thu, Oct 1, 2026, 3:35 AM UTC.