M2.8 earthquake 170 km WSW of Adak, Alaska

A magnitude 2.8 earthquake struck 170 km WSW of Adak, Alaska on Sat, Oct 28, 2023, 9:32 AM HADT (18:32 UTC), 32 km (20 mi) below the surface.

A larger quake followed: M4.7 134 km SW 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
2.8	ML, local (Richter)	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.085 · 18 stations
2.3	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: 161 in the 60 days after this one and 92 in the 30 days before it.

The first 60 of 161.

From the USGS Earthquake Hazards Program and its partner networks, event us7000la4y (also filed as ak023du3o8p0). Read Fri, Oct 2, 2026, 3:35 AM UTC.