M4.3 earthquake 77 km WNW of Atka, Alaska
A magnitude 4.3 earthquake struck 77 km WNW of Atka, Alaska on Tue, Aug 11, 1987, 7:41 AM HADT (16:41 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M5.1 43 km E 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
- 4.3 (mb, body-wave), light
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1987-08-11 16:41:29 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 52.409° N, 175.283° 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 1.5 and up: 4 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 usp00037f1. Read Thu, Oct 1, 2026, 11:32 AM UTC.