30 km SSW of Unalaska, Alaska

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 15 people have reported feeling it to USGS.

How big was it?

This earthquake released about 85 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.5 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 2,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 89× the energy of this one
3. Magna, Utah 2020 M 5.7 63× the energy of this one
4. This earthquake M 4.5 about 85 tons of TNT
5. Around the size people start to feel M 3.0 this one released 180× 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 53.6386, -166.7727. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.1 77 km SW of Unalaska, Alaska 20:44 UTC
2. 2.9 11 km WNW of Dutch Harbor, Alaska 19:09 UTC
3. 2.3 7 km W of Dutch Harbor, Alaska 10:31 UTC
4. 2.1 8 km W of Dutch Harbor, Alaska 17:48 UTC
5. 2.0 8 km W of Dutch Harbor, Alaska 12:36 UTC
6. 2.3 7 km NW of Dutch Harbor, Alaska 12:07 UTC
7. 1.9 7 km W of Dutch Harbor, Alaska 07:58 UTC
8. 2.0 8 km W of Dutch Harbor, Alaska 03:38 UTC
9. 3.2 8 km W of Dutch Harbor, Alaska 03:17 UTC
10. 1.5 6 km W of Dutch Harbor, Alaska 03:14 UTC
11. 3.3 8 km W of Dutch Harbor, Alaska 02:08 UTC
12. 2.2 7 km W of Dutch Harbor, Alaska 01:07 UTC
13. 1.9 49 km SSE of Unalaska, Alaska 23:01 UTC
14. 2.7 69 km SW of Unalaska, Alaska 02:19 UTC
15. 1.6 8 km W of Dutch Harbor, Alaska 10:48 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 17:44 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 6.2 on 2022-01-22 — it released about 350 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.