M3.3 earthquake 38 km ESE of Atka, Alaska

A magnitude 3.3 earthquake struck 38 km ESE of Atka, Alaska on Sat, Sep 16, 2023, 6:15 AM HADT (15:15 UTC), 17 km (10 mi) below the surface.

A larger quake followed: M5.0 129 km E of Atka, 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)	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.148 · 10 stations
2.9	ML, local (Richter)	Alaska Earthquake Center	Preliminary

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Within 100 km, magnitude 1.5 and up: 118 in the 60 days after this one and 98 in the 30 days before it.

The first 60 of 118.

From the USGS Earthquake Hazards Program and its partner networks, event us6000lcau (also filed as ak023bwl7ota). Read Fri, Oct 2, 2026, 6:44 AM UTC.