88 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. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 21 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.1 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 7,900× the energy of this one
2. Mineral, Virginia 2011 M 5.8 350× the energy of this one
3. Magna, Utah 2020 M 5.7 250× the energy of this one
4. This earthquake M 4.1 about 21 tons of TNT
5. Around the size people start to feel M 3.0 this one released 45× 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 53.1282, -166.9761. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.8 127 km S of Unalaska, Alaska 13:19 UTC
2. 2.0 94 km SSW of Unalaska, Alaska 00:25 UTC
3. 2.8 82 km SSW of Unalaska, Alaska 21:21 UTC
4. 2.9 128 km S of Unalaska, Alaska 17:03 UTC
5. 1.9 84 km SSW of Unalaska, Alaska 13:40 UTC
6. 3.4 122 km S of Unalaska, Alaska 12:23 UTC
7. 2.2 118 km S of Unalaska, Alaska 09:27 UTC
8. 4.0 119 km S of Unalaska, Alaska 03:04 UTC
9. 1.9 87 km SSW of Unalaska, Alaska 02:01 UTC
10. 1.6 84 km SSW of Unalaska, Alaska 15:10 UTC
11. 2.7 94 km SSW of Unalaska, Alaska 04:12 UTC
12. 1.5 87 km SSW of Unalaska, Alaska 09:45 UTC
13. 2.6 90 km SSW of Unalaska, Alaska 14:01 UTC
14. 2.2 75 km SSW of Unalaska, Alaska 23:58 UTC
15. 3.1 94 km SSW of Unalaska, Alaska 16:32 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 16:24 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 1,400 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.