M3.3 earthquake 7 km E of Point MacKenzie, Alaska

A magnitude 3.3 earthquake struck 7 km E of Point MacKenzie, Alaska on Fri, Sep 11, 2020, 1:34 PM AKDT (21:34 UTC), 36 km (23 mi) below the surface.

A larger quake followed: M5.1 2 km E of Big Lake, 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
3.3	ML, local (Richter)	Alaska Earthquake Center	Preferred · Preliminary
3.5	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.025 · 206 stations

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

188 people reported to the USGS what they felt; the strongest reported shaking was III, weak shaking.

Reviewed by a seismologist.

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

Within 100 km, magnitude 1.5 and up: 186 in the 60 days after this one and 108 in the 30 days before it.

The first 60 of 186.

From the USGS Earthquake Hazards Program and its partner networks, event ak020bq2qxts (also filed as us7000bm5q). Read Thu, Oct 1, 2026, 5:56 AM UTC.