3.1

M3.1 Earthquake 217 km WSW of Adak, AlaskaApril 21, 2026

2026-04-21 15:21:41 UTC (3 days ago)

On April 21, 2026 at 15:21 UTC, a magnitude 3.1 shallow crustal earthquake struck 217 km WSW of Adak, Alaska, at a depth of 12.5 km and coordinates 50.9087°, -179.3561°.

Map showing earthquake epicenter at 50.91°, -179.36°

Earthquake Details

Magnitude
3.1 ml
Depth
12.5 km
shallow crustal
Location
50.9087°N
-179.3561°E

Technical Information

Event ID
us6000ss2x
Event Type
earthquake
Status
✓ Reviewed
Significance
148
Stations Used
22
Azimuthal Gap
233.0°
Min Station Distance
0.730°
RMS Residual
0.66 sec
Last Updated
2026-04-24 14:18:35 UTC

Common Questions

How strong was the magnitude 3.1 earthquake near Adak, Alaska?

The magnitude 3.1 earthquake that struck 217 km WSW of Adak, Alaska on April 21, 2026 at 15:21 UTC had a depth of 12.5 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.1 earthquakes can continue for several days and gradually diminish over time.

What should I do after an earthquake?

If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.