M2.5 earthquake 38 km SSW of Ugashik, Alaska

A magnitude 2.5 earthquake struck 38 km SSW of Ugashik, Alaska on Sat, Aug 28, 2021, 5:31 AM AKDT (13:31 UTC), 8 km (5 mi) below the surface.

A larger quake followed: M3.3 89 km SE of Ugashik, 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
2.5	ML, local (Richter)	Alaska Earthquake Center	Preferred · Preliminary
2.8	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.062 · 34 stations

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Distance and direction from each place to the epicenter, with its forecast.

Within 100 km, magnitude 1.5 and up: 43 in the 60 days after this one and 70 in the 30 days before it.

From the USGS Earthquake Hazards Program and its partner networks, event ak021b14wnhd (also filed as us7000f586). Read Thu, Oct 1, 2026, 4:12 PM UTC.