M2.9 earthquake 136 km W of Adak, Alaska

A magnitude 2.9 earthquake struck 136 km W of Adak, Alaska on Wed, Mar 11, 2020, 2:12 AM HADT (11:12 UTC), 175 km (109 mi) below the surface.

A larger quake followed: M5.0 71 km WNW of Adak, 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
2.9	ML, local (Richter)	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.128 · 8 stations
2.6	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: 116 in the 60 days after this one and 119 in the 30 days before it.

The first 60 of 116.

From the USGS Earthquake Hazards Program and its partner networks, event us70008i1b (also filed as ak02039ls1gq). Read Thu, Oct 1, 2026, 9:32 PM UTC.