126 km S of Unalaska, Alaska

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 950 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.2 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 180× the energy of this one
2. Mineral, Virginia 2011 M 5.8 7.9× the energy of this one
3. Magna, Utah 2020 M 5.7 5.6× the energy of this one
4. This earthquake M 5.2 about 950 tons of TNT
5. Around the size people start to feel M 3.0 this one released 2,000× 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 52.7426, -166.6507. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 3.1 125 km S of Unalaska, Alaska 09:36 UTC
2. 1.9 111 km S of Unalaska, Alaska 17:56 UTC
3. 2.9 129 km S of Unalaska, Alaska 18:41 UTC
4. 2.1 109 km S of Unalaska, Alaska 09:20 UTC
5. 2.0 119 km S of Unalaska, Alaska 00:55 UTC
6. 2.2 127 km ESE of Nikolski, Alaska 00:36 UTC
7. 2.6 143 km ESE of Nikolski, Alaska 22:03 UTC
8. 2.5 132 km S of Unalaska, Alaska 14:17 UTC
9. 1.9 98 km SSW of Unalaska, Alaska 12:19 UTC
10. 2.1 78 km SSW of Unalaska, Alaska 06:22 UTC
11. 2.7 117 km S of Unalaska, Alaska 14:26 UTC
12. 2.2 139 km S of Unalaska, Alaska 06:51 UTC
13. 2.2 129 km SSW of Unalaska, Alaska 05:22 UTC
14. 2.2 133 km S of Unalaska, Alaska 02:45 UTC
15. 2.0 135 km S of Unalaska, Alaska 07:49 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 18:01 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 2017-05-24 — it released about 11 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.