M4.6 earthquake 122 km WSW of Adak, Alaska
A magnitude 4.6 earthquake struck 122 km WSW of Adak, Alaska on Wed, Aug 21, 1985, 9:07 AM HADT (18:07 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M4.8 180 km WSW of Adak, Alaska. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.6 (mb), light
- Local time
- UTC
- 1985-08-21 18:07:48 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 51.637° N, 178.362° 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
Nearby
Within 100 km, magnitude 1.6 and up: 3 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 usp0002hzk. Read Wed, Sep 30, 2026, 7:40 AM UTC.