189 km E of Atka, 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 340 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.9 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 500× the energy of this one
2. Mineral, Virginia 2011 M 5.8 22× the energy of this one
3. Magna, Utah 2020 M 5.7 16× the energy of this one
4. This earthquake M 4.9 about 340 tons of TNT
5. Around the size people start to feel M 3.0 this one released 710× 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 52.1824, -171.4322. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 4.0 195 km E of Atka, Alaska 10:44 UTC
2. 3.3 190 km E of Atka, Alaska 10:36 UTC
3. 3.0 188 km E of Atka, Alaska 18:05 UTC
4. 5.6 165 km SW of Nikolski, Alaska 11:48 UTC
5. 2.5 163 km WSW of Nikolski, Alaska 11:31 UTC
6. 3.2 182 km ESE of Atka, Alaska 14:37 UTC
7. 3.3 172 km E of Atka, Alaska 07:24 UTC
8. 4.2 171 km E of Atka, Alaska 04:49 UTC
9. 2.9 173 km ESE of Atka, Alaska 18:23 UTC
10. 2.8 171 km WSW of Nikolski, Alaska 13:58 UTC
11. 3.1 173 km E of Atka, Alaska 01:10 UTC
12. 3.5 192 km ESE of Atka, Alaska 07:01 UTC
13. 2.3 169 km WSW of Nikolski, Alaska 08:08 UTC
14. 3.6 176 km WSW of Nikolski, Alaska 15:33 UTC
15. 2.9 191 km ESE of Atka, Alaska 10:48 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 14:15 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 2018-08-25 — it released about 32 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.