M3.1 earthquake 260 km SW of Adak, Alaska
A magnitude 3.1 earthquake struck 260 km SW of Adak, Alaska on Mon, May 21, 2018, 6:14 AM HADT (15:14 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
- 3.1 (ML, local (Richter)), minor
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 2018-05-21 15:14:13 UTC
- Depth
- 10.0 km (6.2 mi), shallow
- Epicenter
- 49.952° N, 178.757° W
- Region
- Alaska
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Magnitude estimates
Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.
| Mag. | Scale | Computed by | Notes |
|---|---|---|---|
| 3.1 | ML, local (Richter) | USGS National Earthquake Information Center | Preferred · Reviewed |
| 3.0 | ML, local (Richter) | Alaska Earthquake Center | Preliminary |
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 7.5 km horizontally, 2.0 km in depth
- Depth from
- Operator assigned
- Station coverage gap
- 260°, poorly surrounded by stations
- Stations used
- 14
Nearby
Within 100 km, magnitude 1.5 and up: 3 in the 60 days after this one and 3 in the 30 days before it.
After
- 2.6212 km SSW of Adak, Alaska · 3041 days ago · 29 km deep · 69 km away
- 2.7269 km SW of Adak, Alaska · 3039 days ago · 33 km deep · 35 km away
- 2.3229 km SSW of Adak, Alaska · 2997 days ago · 5 km deep · 76 km away
Before
Earthquakes todayAlaska earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event us1000ectw (also filed as ak0186hfsh68, ak19667762). Read Fri, Oct 2, 2026, 10:30 AM UTC.