150 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 120 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.6 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 1,400× the energy of this one
2. Mineral, Virginia 2011 M 5.8 63× the energy of this one
3. Magna, Utah 2020 M 5.7 45× the energy of this one
4. This earthquake M 4.6 about 120 tons of TNT
5. Around the size people start to feel M 3.0 this one released 250× 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 53.5034, -163.2913. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.8 159 km S of False Pass, Alaska 23:04 UTC
2. 1.9 115 km S of False Pass, Alaska 02:11 UTC
3. 3.0 161 km S of False Pass, Alaska 01:45 UTC
4. 1.7 103 km S of False Pass, Alaska 07:38 UTC
5. 2.7 142 km S of False Pass, Alaska 15:31 UTC
6. 2.8 153 km S of False Pass, Alaska 08:57 UTC
7. 2.8 143 km SSE of False Pass, Alaska 15:46 UTC
8. 2.6 161 km ESE of Akutan, Alaska 15:21 UTC
9. 2.1 105 km S of False Pass, Alaska 12:23 UTC
10. 2.4 115 km S of False Pass, Alaska 22:36 UTC
11. 2.3 162 km ESE of Akutan, Alaska 19:43 UTC
12. 4.2 Unimak Island region, Alaska 18:49 UTC
13. 2.0 114 km S of False Pass, Alaska 07:01 UTC
14. 2.1 108 km S of False Pass, Alaska 02:17 UTC
15. 2.1 131 km S of False Pass, Alaska 21:10 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 15:25 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 5.9 on 2016-10-27 — it released about 89 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.