M1.6 earthquake 41 km ENE of Adak, Alaska

A magnitude 1.6 earthquake struck 41 km ENE of Adak, Alaska on Thu, Jul 9, 2020, 2:00 AM HADT (11:00 UTC), 4 km (3 mi) below the surface.

A larger quake followed: M5.2 52 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
1.6	ML, local (Richter)	Alaska Earthquake Center	Preferred · Preliminary
1.53	ML, local (Richter)	AV	Final · ±0.422 · 10 stations

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Within 100 km, magnitude 1.5 and up: 147 in the 60 days after this one and 71 in the 30 days before it.

The first 60 of 147.

From the USGS Earthquake Hazards Program and its partner networks, event ak0208s274de (also filed as av70906804). Read Fri, Oct 2, 2026, 2:50 PM UTC.