215 km SE of Chignik, Alaska

Yes. A magnitude 3.4 earthquake was recorded 215 km SE of Chignik, Alaska at 20:20 UTC on 2025-09-12, 57 km deep. The magnitude and location are an automatic first estimate and may change.

2025-09-12 20:20 UTC · 57 km deep · released about 1.9 tons of TNT

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Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.

When: 2025-09-12 20:20 UTC
Magnitude: M 3.4 (ml)
Depth: 57 km below the surface
Felt: no reports yet
Status: Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS 346 days ago · we first saw it 346 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 8 km (5 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 1.9 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

Northridge, California 1994 M 6.7 89,000× the energy of this one
Mineral, Virginia 2011 M 5.8 4,000× the energy of this one
Magna, Utah 2020 M 5.7 2,800× the energy of this one
This earthquake M 3.4 about 1.9 tons of TNT
Around the size people start to feel M 3.0 this one released 4× more

Energy from the Gutenberg–Richter relation (log₁₀E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

The largest earthquake within 50 km since 2016 was M 5.6 on 2021-09-16 — about 2,000 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

6.2 189 km SE of Chignik, Alaska · 28 km WNW of this epicentre Mar 18, 1945
6.1 210 km SE of Chignik, Alaska · 45 km NE of this epicentre Nov 15, 1955
6.0 223 km SSW of Akhiok, Alaska · 46 km NE of this epicentre Nov 7, 1928
6.0 168 km SE of Chignik, Alaska · 49 km NNW of this epicentre Nov 16, 1938
5.6 171 km SE of Chignik, Alaska · 43 km NW of this epicentre Jun 22, 1970

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

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Aftershocks so far

10 earthquakes have been recorded within 50 km since this one.

3.1 243 km SE of Chignik, Alaska 06:03 UTC
3.0 195 km SE of Chignik, Alaska 05:59 UTC
3.3 190 km SE of Chignik, Alaska 04:59 UTC
2.8 190 km SE of Chignik, Alaska 04:29 UTC
3.2 187 km SE of Chignik, Alaska 17:30 UTC
2.8 226 km SE of Chignik, Alaska 03:58 UTC
3.7 197 km SE of Chignik, Alaska 00:35 UTC
3.7 212 km SE of Chignik, Alaska 15:48 UTC
3.4 208 km SE of Chignik, Alaska 01:29 UTC
3.9 202 km SE of Chignik, Alaska 12:22 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 15:40 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

The official USGS event page — the source of record for every value above
Did you feel it? Report it to USGS — reports go to USGS, not to us
ShakeMap for this event, when USGS has produced one

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.