M4.3 earthquake 248 km WSW of Adak, Alaska
A magnitude 4.3 earthquake struck 248 km WSW of Adak, Alaska on Mon, Aug 24, 1987, 6:42 PM GMT-12 (06:42 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M4.9 298 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
- 4.3 (mb, body-wave), light
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1987-08-25 06:42:20 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 50.785° N, 179.749° 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: 1 in the 60 days after this one and 7 in the 30 days before it.
After
Before
- 5.0177 km WSW of Adak, Alaska · 14296 days ago · 33 km deep · 74 km away
- 4.8289 km WSW of Adak, Alaska · 14297 days ago · 33 km deep · 85 km away
- 4.4282 km WSW of Adak, Alaska · 14298 days ago · 33 km deep · 58 km away
- 4.3Rat Islands, Aleutian Islands, Alaska · 14303 days ago · 33 km deep · 82 km away
- 4.8154 km WSW of Adak, Alaska · 14308 days ago · 33 km deep · 94 km away
- 4.6161 km WSW of Adak, Alaska · 14308 days ago · 33 km deep · 88 km away
- 4.8173 km WSW of Adak, AK · 14311 days ago · 33 km deep · 76 km away
Earthquakes todayAlaska earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp00037tb. Read Fri, Oct 2, 2026, 4:12 PM UTC.