111 km ESE of Akutan, Alaska

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

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 250,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
4. This earthquake M 3.1 about 1,300 lb of TNT
5. Around the size people start to feel M 3.0 this one released 1.4× 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.

Where

Epicentre 53.8423, -164.1478. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.0 111 km SSW of False Pass, Alaska 03:07 UTC
2. 2.7 112 km ESE of Akutan, Alaska 12:10 UTC
3. 2.8 113 km ESE of Akutan, Alaska 10:23 UTC
4. 3.1 Unimak Island region, Alaska 08:36 UTC
5. 3.7 110 km ESE of Akutan, Alaska 00:01 UTC
6. 2.8 112 km ESE of Akutan, Alaska 13:48 UTC
7. 2.2 102 km S of False Pass, Alaska 06:28 UTC
8. 2.9 101 km SSW of False Pass, Alaska 22:11 UTC
9. 2.5 103 km SE of Akutan, Alaska 11:14 UTC
10. 2.1 87 km S of False Pass, Alaska 17:00 UTC
11. 2.2 112 km ESE of Akutan, Alaska 06:52 UTC
12. 2.2 96 km ESE of Akutan, Alaska 21:41 UTC
13. 2.9 Unimak Island region, Alaska 20:42 UTC
14. 2.1 93 km SSW of False Pass, Alaska 05:27 UTC
15. 2.1 124 km ESE of Akutan, Alaska 10:39 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 17:27 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 5.1 on 2021-01-11 — it released about 1,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

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.