Alaska earthquakes

M5.4 earthquake 89 km SE of Adak, Alaska

A magnitude 5.4 earthquake struck 89 km SE of Adak, Alaska on Fri, Nov 4, 1977, 7:07 AM GMT-11 (18:07 UTC), 33 km (21 mi) below the surface.

A larger quake followed: M5.6 83 km ESE of Adak, Alaska. This one was a foreshock.

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Where this earthquake was located, with the others nearby. Select one for its page.

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The earthquake

Magnitude: 5.4 (Ms, surface-wave), moderate
Magnitude from: USGS National Earthquake Information Center
Local time: Fri, Nov 4, 1977, 7:07 AM GMT-11
UTC: 1977-11-04 18:07:31 UTC
Depth: 33.0 km (20.5 mi), shallow
Epicenter: 51.429° N, 175.558° W
Region: Alaska
Tsunami flag: No
Status: Reviewed by a seismologist

Magnitude estimates

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
5.4	Ms, surface-wave	USGS National Earthquake Information Center	Preferred · Reviewed
5.87	Mw, moment	ISC-GEM global catalog	Final · ±0.1
5.9	Mwc, centroid moment	Global CMT project	Preliminary

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

Reviewed by a seismologist.

Depth from: OPERATOR_ASSIGNED
Stations used: 158

Nearby

Within 100 km, magnitude 2.4 and up: 9 in the 60 days after this one and 4 in the 30 days before it.

After

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event usp0000rcg (also filed as gcmtb110477b, gcmt19771104180731, iscgem689909). Read Sat, Oct 3, 2026, 7:50 PM UTC.