M4.2 earthquake 201 km SE of Unalaska, Alaska
A magnitude 4.2 earthquake struck 201 km SE of Unalaska, Alaska on Thu, Mar 31, 1983, 7:50 PM GMT-10 (05:50 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M4.5 218 km SE of Akutan, Alaska. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.2 (mb), light
- Local time
- UTC
- 1983-04-01 05:50:34 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 52.386° N, 164.822° W
- Region
- Alaska
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
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
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.5 and up: 1 in the 60 days after this one and 0 in the 30 days before it.
After
Earthquakes todayAlaska earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0001u3s. Read Tue, Sep 22, 2026, 10:30 PM UTC.