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SeismoAtlas

M2.1 earthquake – False Pass, Alaska

A magnitude 2.1 earthquake struck in the False Pass, Alaska region at 10:43 UTC on 22 Sept 2026, at a depth of 11 km, according to USGS.

Data: USGS · updated 2026-09-22 20:15 UTC · reviewed

Magnitude
2.1micro
local magnitude (Richter) (ml)
Depth
11.1 km
Status
Reviewed
Origin time
2026-09-22 10:43:15 UTC
Epicentre
54.544° N, 163.523° 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

Distance and estimated shaking at nearby places
PlaceDistanceEst. 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.

AgencyMagnitudeDepthEpicentreTime offsetStatus
USGS · AVheadlineAlaska Volcano Observatory via U.S. Geological Survey2.1 ml11.1 km54.54° N, 163.52° W–Reviewed

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How big was it?

Usually not felt. Recorded by nearby seismometers; thousands occur worldwide every day.

It released roughly the energy of 24 kg 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 11 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.

M2.1 releases about 36× the energy of M1.1, and its waves are about 11× taller on a seismogram. Energy: 24 kg of TNT vs 674 g of TNT.

Each square is the energy of one M1.1. Energy from log₁₀E = 1.5M + 4.8.

Aftershocks and nearby activity

1 later earthquake within 30 km; the largest was M1.5 5 days ago. 1 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.

Aftershocks

Mainshock M2.1

1 later earthquake nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).

Aftershocks
Time after mainshock (hours)MagnitudeDepth (km)
28.861.56
  1. 1.5False Pass, Alaska09-23 15:35

Did you feel it?

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Reports on SeismoAtlas

No reports yet.

Event id av94443351. First recorded here 28 Sept 2026, 17:32:12 UTC. Solutions: USGS · AV (usgs:av94443351). Cite as: SeismoAtlas, “M2.1 earthquake – False Pass, Alaska”, https://seismoatlas.com/earthquake/av94443351-m2-1-earthquake-false-pass-alaska, data from USGS.

JSON: /api/v1/events/av94443351. SeismoAtlas is not an official warning service.