M0.4 earthquake – Chignik Lake, Alaska
A magnitude 0.4 earthquake struck in the Chignik Lake, Alaska region at 10:37 UTC on 12 Oct 2026, at a depth of 6 km, according to USGS.
Data: USGS · updated 2026-10-13 00:16 UTC · reviewed
- Magnitude
- 0.4micro
local magnitude (Richter) (ml) - Depth
- 5.5 km
- Status
- Reviewed
- Origin time
- 2026-10-12 10:37:25 UTC
- Epicentre
- 56.243° N, 159.341° W
Circles show this event and others within 30 km from 7 days before to 30 days after. Lines: plate boundaries and GEM active faults. Open on the live map
Nearby places
| Place | Distance | Est. shaking |
|---|---|---|
| No towns within 400 km. This is a remote area. | ||
Shaking is an estimate from the intensity prediction equation of Allen, Wald & Worden (2012), not an observation. Local ground and buildings can change it by a level or more.
Every agency's solution
Agencies locate earthquakes with their own stations and methods, so their numbers differ. We match reports of the same event by time, distance and magnitude and show them side by side. The headline uses USGS · AV, which has been reviewed by an analyst.
| Agency | Magnitude | Depth | Epicentre | Time offset | Status |
|---|---|---|---|---|---|
| USGS · AVheadlineAlaska Volcano Observatory via U.S. Geological Survey | 0.4 ml | 5.5 km | 56.24° N, 159.34° W | – | Reviewed |
How big was it?
Usually not felt. Recorded by nearby seismometers; thousands occur worldwide every day.
It released roughly the energy of 56 g of TNT. Magnitude is logarithmic: each whole step means about 32 times more energy and 10 times larger waves on a seismogram. Depth matters too: at 6 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.
M1.0 releases about 8.5× the energy of M0.4, and its waves are about 4.2× taller on a seismogram. Energy: 477 g of TNT vs 56 g of TNT.
Each square is the energy of one M0.4. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
1 later earthquake within 30 km; the largest was M-0.3 1 day ago. 2 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.
Mainshock M0.4
1 later earthquake nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).
| Time after mainshock (hours) | Magnitude | Depth (km) |
|---|---|---|
| 2.87 | -0.3 | 4 |
Did you feel it?
Reports from people help show where shaking was strong. They are anonymous and shown here in aggregate.
Reports on SeismoAtlas
No reports yet.
Event id av94444963. First recorded here 13 Oct 2026, 00:21:47 UTC. Solutions: USGS · AV (usgs:av94444963). Cite as: SeismoAtlas, “M0.4 earthquake – Chignik Lake, Alaska”, https://seismoatlas.com/earthquake/av94444963-m0-4-earthquake-chignik-lake-alaska, data from USGS.
JSON: /api/v1/events/av94444963. SeismoAtlas is not an official warning service.