M3.0 earthquake 40 km E of Port Alsworth, Alaska

A magnitude 3.0 earthquake struck 40 km E of Port Alsworth, Alaska on Fri, Sep 20, 2019, 3:05 PM AKDT (23:05 UTC), 176 km (109 mi) below the surface.

A larger quake followed: M3.9 47 km NE of Pedro Bay, 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
3.0	ML, local (Richter)	Alaska Earthquake Center	Preferred · Preliminary
3.0	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed

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 201 in the 60 days after this one and 123 in the 30 days before it.

The first 60 of at least 201.

From the USGS Earthquake Hazards Program and its partner networks, event ak019c3c2f6m (also filed as us60005lly). Read Sun, Oct 4, 2026, 6:59 AM UTC.