M1.6 earthquake 18 km W of Adak, Alaska

A magnitude 1.6 earthquake struck 18 km W of Adak, Alaska on Tue, Jul 23, 2019, 8:00 PM HADT (05:00 UTC), 11 km (7 mi) below the surface.

A larger quake followed: M4.0 59 km SE 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
1.71	ML, local (Richter)	AV	Final · ±0.232 · 15 stations

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Within 100 km, magnitude 1.5 and up: 128 in the 60 days after this one and 75 in the 30 days before it.

The first 60 of 128.

From the USGS Earthquake Hazards Program and its partner networks, event ak0199f45drt (also filed as av62052646). Read Thu, Oct 1, 2026, 7:16 PM UTC.