M2.7 earthquake 8 km SW of Clam Gulch, Alaska

A magnitude 2.7 earthquake struck 8 km SW of Clam Gulch, Alaska on Wed, Apr 21, 2021, 4:45 PM AKDT (00:45 UTC), 62 km (38 mi) below the surface.

A larger quake followed: M3.7 50 km WNW of Nanwalek, 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
2.7	ML, local (Richter)	Alaska Earthquake Center	Preferred · Preliminary
2.9	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.028 · 162 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: at least 199 in the 60 days after this one and at least 200 in the 30 days before it.

The first 60 of at least 199.

From the USGS Earthquake Hazards Program and its partner networks, event ak021558gltr (also filed as us6000e3j8). Read Fri, Oct 2, 2026, 5:26 PM UTC.