151 km SE of Akutan, 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 53.3100, -163.9454. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.5 121 km ESE of Akutan, Alaska 07:38 UTC
2. 2.5 146 km ESE of Akutan, Alaska 00:43 UTC
3. 3.0 124 km ESE of Akutan, Alaska 13:33 UTC
4. 2.7 129 km ESE of Akutan, Alaska 12:13 UTC
5. 2.7 164 km S of False Pass, Alaska 13:39 UTC
6. 3.5 156 km S of False Pass, Alaska 03:11 UTC
7. 2.7 121 km ESE of Akutan, Alaska 09:49 UTC
8. 2.4 132 km SE of Akutan, Alaska 04:08 UTC
9. 2.5 138 km SE of Akutan, Alaska 16:36 UTC
10. 2.6 188 km SE of Akutan, Alaska 15:13 UTC
11. 2.3 155 km SE of Akutan, Alaska 08:36 UTC
12. 2.5 142 km SE of Akutan, Alaska 23:02 UTC
13. 3.1 140 km SE of Akutan, Alaska 22:58 UTC
14. 3.0 122 km SE of Akutan, Alaska 22:56 UTC
15. 2.9 142 km SE of Akutan, Alaska 18:54 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 18:50 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 5.7 on 2020-08-13 — it released about 45 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.