M4.1 earthquake 147 km NNE of Adak, Alaska
A magnitude 4.1 earthquake struck 147 km NNE of Adak, Alaska on Wed, Oct 20, 2021, 8:10 AM HADT (17:10 UTC), 10 km (6 mi) below the surface.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.1 (mb), light
- Local time
- UTC
- 2021-10-20 17:10:37 UTC
- Depth
- 10.0 km (6.2 mi), shallow
- Epicenter
- 53.142° N, 176.023° 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.
- Location uncertainty
- About 4.8 km horizontally, 2.0 km in depth
- Magnitude uncertainty
- ±0.14
- Depth from
- Operator assigned
- Station coverage gap
- 142°
- Stations used
- 32
Nearby
Within 100 km, magnitude 1.5 and up: 4 in the 60 days after this one and 3 in the 30 days before it.
After
- 2.998 km NNE of Adak, Alaska · 1779 days ago · 226 km deep · 50 km away
- 2.276 km NE of Adak, Alaska · 1776 days ago · 214 km deep · 97 km away
- 3.365 km NE of Adak, Alaska · 1761 days ago · 191 km deep · 96 km away
- 2.9Andreanof Islands, Aleutian Islands, Alaska · 1756 days ago · 153 km deep · 100 km away
Before
Earthquakes todayAlaska earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event us6000fw9u. Read Thu, Sep 24, 2026, 5:45 AM UTC.