M4.9 earthquake 298 km WSW of Adak, Alaska
A magnitude 4.9 earthquake struck 298 km WSW of Adak, Alaska on Tue, Sep 15, 1987, 7:25 PM GMT+12 (07:25 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M5.1 270 km W 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
- 4.9 (mb), light
- Local time
- UTC
- 1987-09-15 07:25:54 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 51.059° N, 179.270° E
- 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 1.9 and up: 2 in the 60 days after this one and 1 in the 30 days before it.
After
- 4.5285 km W of Adak, Alaska · 14242 days ago · 33 km deep · 49 km away
- 5.1270 km W of Adak, Alaska · 14223 days ago · 95 km deep · 98 km away
Before
Earthquakes todayAlaska earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp00038dr. Read Tue, Sep 29, 2026, 11:39 AM UTC.