M2.6 earthquake 165 km S of Adak, Alaska

A magnitude 2.6 earthquake struck 165 km S of Adak, Alaska on Thu, Jul 20, 2023, 11:14 PM HADT (08:14 UTC), 10 km (6 mi) below the surface.

A larger quake followed: M4.0 173 km SSW 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
2.6	ML, local (Richter)	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.128 · 8 stations
2.5	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: 25 in the 60 days after this one and 13 in the 30 days before it.

From the USGS Earthquake Hazards Program and its partner networks, event us6000kvz7 (also filed as ak0239a7emi4). Read Fri, Oct 2, 2026, 5:46 AM UTC.