50 km NW of Nelson Lagoon, Alaska

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre.

At this magnitude and depth, people at rest would likely notice it out to about 119 km (74 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 1.3 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.3 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 130× the energy of this one
2. Mineral, Virginia 2011 M 5.8 5.6× the energy of this one
3. Magna, Utah 2020 M 5.7 4× the energy of this one
4. This earthquake M 5.3 about 1.3 kilotons of TNT
5. Around the size people start to feel M 3.0 this one released 2,800× 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.

For this area

The largest earthquake within 50 km (31 mi) since our catalogue begins in 2016. The previous largest was M 5.0 on 2016-03-06.

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

1. 5.8 80 km NNW of Nelson Lagoon, Alaska · 34 km N of this epicentre Jan 20, 2000
2. 5.7 Alaska Peninsula · 25 km ESE of this epicentre Jun 10, 1968
3. 5.0 44 km WSW of Nelson Lagoon, Alaska · 45 km S of this epicentre Feb 21, 1977
4. 5.0 54 km NW of Nelson Lagoon, Alaska · 11 km NNE of this epicentre May 30, 1979
5. 5.0 38 km WNW of Nelson Lagoon, Alaska · 26 km S of this epicentre Jul 15, 2007

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 56.3108, -161.8025. Map © OpenStreetMap contributors.

Nearby places

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

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

1. 2.9 20 km WSW of Nelson Lagoon, Alaska 09:55 UTC
2. 2.8 39 km WNW of Nelson Lagoon, Alaska 11:04 UTC
3. 2.0 39 km W of Nelson Lagoon, Alaska 10:33 UTC
4. 5.2 37 km NW of Nelson Lagoon, Alaska 05:27 UTC
5. 2.7 9 km NW of Nelson Lagoon, Alaska 06:28 UTC
6. 2.9 36 km WNW of Nelson Lagoon, Alaska 23:48 UTC
7. 3.1 40 km NNW of Nelson Lagoon, Alaska 11:01 UTC
8. 3.4 35 km WSW of Nelson Lagoon, Alaska 01:53 UTC
9. 3.3 15 km NNW of Nelson Lagoon, Alaska 05:57 UTC
10. 2.2 14 km W of Nelson Lagoon, Alaska 02:43 UTC
11. 2.9 15 km NW of Nelson Lagoon, Alaska 01:35 UTC
12. 3.0 55 km WNW of Nelson Lagoon, Alaska 14:49 UTC
13. 2.7 17 km WNW of Nelson Lagoon, Alaska 14:40 UTC
14. 2.5 15 km NW of Nelson Lagoon, Alaska 05:28 UTC
15. 2.5 31 km NNW of Nelson Lagoon, Alaska 08:39 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 23:42 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.