84 km S of False Pass, Alaska

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

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 54.0945, -163.5304. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.3 88 km S of False Pass, Alaska 14:20 UTC
2. 2.6 55 km SSW of False Pass, Alaska 11:34 UTC
3. 2.3 103 km S of False Pass, Alaska 05:59 UTC
4. 2.1 90 km S of False Pass, Alaska 20:42 UTC
5. 2.2 108 km SSW of False Pass, Alaska 19:57 UTC
6. 1.8 92 km S of False Pass, Alaska 15:30 UTC
7. 2.5 96 km S of False Pass, Alaska 00:57 UTC
8. 2.4 Unimak Island region, Alaska 02:54 UTC
9. 2.1 89 km SSE of False Pass, Alaska 11:45 UTC
10. 2.3 109 km SSW of False Pass, Alaska 13:32 UTC
11. 2.5 103 km S of False Pass, Alaska 19:23 UTC
12. 2.3 37 km S of False Pass, Alaska 08:17 UTC
13. 2.2 97 km S of False Pass, Alaska 00:53 UTC
14. 2.6 90 km S of False Pass, Alaska 20:58 UTC
15. 2.8 88 km S of False Pass, Alaska 18:37 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 23:25 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 4.5 on 2016-11-14.

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.