89 km SE of Ugashik, Alaska

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 5 km (3 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
3. Around the size people start to feel M 3.0 180× the energy of this one
4. This earthquake M 1.5 about 5.4 lb of TNT

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.

For this area

The largest earthquake within 50 km since 2016 was M 4.6 on 2022-04-10 — about 45,000 times the energy of this one.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

1. 6.8 117 km SSE of Ugashik, Alaska · 50 km SSW of this epicentre May 29, 2015
2. 5.4 115 km SSE of Ugashik, Alaska · 44 km SSW of this epicentre Jun 9, 1971
3. 5.4 60 km E of Ugashik, Alaska · 48 km NNW of this epicentre Sep 26, 1983
4. 5.4 113 km SSE of Ugashik, Alaska · 49 km SSW of this epicentre Jan 27, 2004
5. 5.0 113 km SE of Ugashik, Alaska · 32 km S of this epicentre Dec 30, 2010

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 57.0277, -156.2137. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 1.6 46 km ESE of Ugashik, Alaska 21:17 UTC
2. 2.1 61 km SE of Ugashik, Alaska 16:23 UTC
3. 2.1 54 km SE of Ugashik, Alaska 05:48 UTC
4. 1.9 66 km SE of Ugashik, Alaska 22:46 UTC
5. 1.8 109 km SE of Ugashik, Alaska 12:37 UTC
6. 2.2 87 km SE of Ugashik, Alaska 22:45 UTC
7. 2.4 107 km W of Akhiok, Alaska 09:12 UTC
8. 1.9 71 km ESE of Ugashik, Alaska 16:51 UTC
9. 2.5 87 km SE of Ugashik, Alaska 08:13 UTC
10. 1.8 93 km W of Akhiok, Alaska 17:18 UTC
11. 1.9 114 km SSE of Ugashik, Alaska 11:27 UTC
12. 2.0 107 km W of Akhiok, Alaska 08:20 UTC
13. 1.7 80 km SE of Ugashik, Alaska 09:15 UTC
14. 1.9 84 km SE of Ugashik, Alaska 13:42 UTC
15. 2.1 119 km SSE of Ugashik, Alaska 07:59 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 20:00 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

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.