M1.8 earthquake 79 km WSW of Nanwalek, Alaska

A magnitude 1.8 earthquake struck 79 km WSW of Nanwalek, Alaska on Fri, Sep 25, 2020, 3:57 AM AKDT (11:57 UTC), 9 km (5 mi) below the surface.

A larger quake followed: M3.9 59 km SSE of Kokhanok, 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
1.8	ML, local (Richter)	Alaska Earthquake Center	Preferred · Preliminary
1.8	ML, local (Richter)	AV	Final · ±0.303554084097386 · 17 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 100 in the 30 days before it.

The first 60 of at least 199.

From the USGS Earthquake Hazards Program and its partner networks, event ak020cd2gedk (also filed as av91127796). Read Fri, Oct 2, 2026, 3:20 PM UTC.