52 km ESE of Chignik, Alaska

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 1 km (1 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 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
3. Around the size people start to feel M 3.0 22× the energy of this one
4. This earthquake M 2.1 about 43 lb of TNT

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 4.4 on 2025-12-03 — about 2,800 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

1. 6.5 60 km ENE of Chignik, Alaska · 45 km N of this epicentre Sep 28, 1941
2. 6.4 77 km ESE of Chignik, Alaska · 28 km E of this epicentre Mar 24, 1972
3. 5.8 46 km S of Chignik, Alaska · 49 km WSW of this epicentre Feb 21, 1972
4. 5.5 51 km SSE of Chignik, Alaska · 46 km SW of this epicentre Feb 24, 1972
5. 5.1 85 km ESE of Chignik, Alaska · 34 km E of this epicentre Jan 7, 2006

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

Epicentre 56.1010, -157.6370. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.6 79 km E of Chignik, Alaska 06:42 UTC
2. 2.4 57 km SE of Chignik, Alaska 22:35 UTC
3. 2.1 37 km SE of Chignik, Alaska 13:59 UTC
4. 2.2 48 km E of Chignik, Alaska 21:47 UTC
5. 2.4 63 km ESE of Chignik, Alaska 18:54 UTC
6. 3.0 79 km E of Chignik, Alaska 22:15 UTC
7. 3.2 69 km SE of Chignik, Alaska 18:07 UTC
8. 2.5 59 km ESE of Chignik, Alaska 17:29 UTC
9. 2.5 42 km SSE of Chignik, Alaska 21:06 UTC
10. 3.6 55 km SE of Chignik, Alaska 17:10 UTC
11. 2.0 92 km SE of Chignik, Alaska 06:25 UTC
12. 2.5 49 km ESE of Chignik, Alaska 21:11 UTC
13. 1.6 36 km ENE of Chignik, Alaska 19:55 UTC
14. 2.4 39 km SSE of Chignik, Alaska 00:16 UTC
15. 2.1 30 km E of Chignik, Alaska 12:27 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 08:25 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.