M2.8 earthquake 60 km E of Port Alsworth, Alaska

A magnitude 2.8 earthquake struck 60 km E of Port Alsworth, Alaska on Fri, Aug 27, 2021, 4:50 PM AKDT (00:50 UTC), 142 km (88 mi) below the surface.

Automatic solution: the magnitude and location may still be revised.

A larger quake followed: M4.7 12 km SSW of Clam Gulch, 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
2.8	ML, local (Richter)	Alaska Earthquake Center	Preferred · Preliminary
3.0	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.035 · 108 stations

No one has reported feeling this quake to the USGS.

An automatic solution; a seismologist may revise it.

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

Within 100 km, magnitude 1.5 and up: at least 201 in the 60 days after this one and 174 in the 30 days before it.

The first 60 of at least 201.

From the USGS Earthquake Hazards Program and its partner networks, event ak021b0xa1va (also filed as us7000f52z). Read Sat, Oct 3, 2026, 6:14 AM UTC.