119 km E of Chignik, Alaska

47 days ago

USGS

A magnitude 4.0 earthquake struck 119 km E of Chignik, Alaska on 15 Sept 2026, 14:32 UTC. The hypocentre was 17.9 km below the surface — shallow by seismological convention. The figures have been revised 1 time since the first report.

Depth: 17.9 km
Latitude: 56.20°N
Time: 14:32 UTC
Magnitude: M4.0

EPICENTRE

View the official report↗

MAGNITUDE 4.0

Noticeable shaking of indoor objects. Damage is unlikely.

The scale is logarithmic: this released about 32 times the energy of a magnitude 3.0, roughly the energy of 15 tonnes of TNT.

17.9 KM DEEP

Shallow earthquakes release their energy close to the surface, so they are felt more strongly, and do more damage, than deeper earthquakes of the same magnitude.