103 km S of Sand Point, 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 275 km (171 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 3.8 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.6 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 45× the energy of this one
2. Mineral, Virginia 2011 M 5.8 2× the energy of this one
3. Magna, Utah 2020 M 5.7 1.4× the energy of this one
4. This earthquake M 5.6 about 3.8 kilotons of TNT
5. Around the size people start to feel M 3.0 this one released 7,900× 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 4.9 on 2018-04-14.

Before 2016, the USGS record lists 25 earthquakes of M5 or more within 50 km; the five largest:

1. 7.1 90 km SE of King Cove, Alaska · 32 km NW of this epicentre May 14, 1948
2. 6.4 101 km SSW of Sand Point, Alaska · 21 km WNW of this epicentre Jul 25, 1917
3. 6.4 109 km SSE of King Cove, Alaska · 47 km WSW of this epicentre Nov 6, 1941
4. 6.4 85 km ESE of King Cove, Alaska · 38 km NW of this epicentre Oct 13, 1999
5. 6.0 75 km ESE of King Cove, Alaska · 49 km NW of this epicentre Jan 27, 1979

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 54.4223, -160.7673. 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. 2.1 90 km SSW of Sand Point, Alaska 15:59 UTC
2. 2.6 101 km SSW of Sand Point, Alaska 23:15 UTC
3. 2.0 85 km SSW of Sand Point, Alaska 07:31 UTC
4. 2.0 79 km SSW of Sand Point, Alaska 02:06 UTC
5. 2.3 117 km SE of King Cove, Alaska 15:18 UTC
6. 1.8 105 km SE of King Cove, Alaska 20:43 UTC
7. 1.8 61 km S of Sand Point, Alaska 00:50 UTC
8. 2.0 61 km S of Sand Point, Alaska 23:25 UTC
9. 3.5 114 km S of Sand Point, Alaska 09:32 UTC
10. 1.8 74 km SSW of Sand Point, Alaska 06:10 UTC
11. 1.5 84 km SSW of Sand Point, Alaska 00:32 UTC
12. 1.5 66 km S of Sand Point, Alaska 21:40 UTC
13. 1.8 88 km SSW of Sand Point, Alaska 19:05 UTC
14. 1.7 96 km S of Sand Point, Alaska 01:45 UTC
15. 2.2 142 km S of Sand Point, Alaska 19:20 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 22:37 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.