Earthquake near Dutch Harbor, AK

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 51 km (32 mi) from the epicentre. In Dutch Harbor, 34 km away, the estimate is intensity II (weak). 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.

Likely felt in: Unalaska 36 km, intensity II · Akutan 41 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 43 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.3 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 4,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 180× the energy of this one
3. Magna, Utah 2020 M 5.7 130× the energy of this one
4. This earthquake M 4.3 about 43 tons of TNT
5. Around the size people start to feel M 3.0 this one released 89× 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 since 2016 was M 4.6 on 2018-11-15 — about 2.8 times the energy of this one.

Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:

1. 5.9 27 km WNW of Dutch Harbor, Alaska · 40 km WSW of this epicentre Apr 21, 1972
2. 5.9 13 km NE of Dutch Harbor, Alaska · 24 km S of this epicentre Sep 1, 2006
3. 5.3 22 km ENE of Dutch Harbor, Alaska · 25 km SSE of this epicentre Dec 22, 1988
4. 5.2 25 km W of Akutan, Alaska · 16 km ESE of this epicentre Aug 20, 2010
5. 5.1 18 km N of Akutan, Alaska · 42 km ENE of this epicentre Jan 6, 1975

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 54.1844, -166.3994. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 1.6 12 km SW of Akutan, Alaska 19:10 UTC
2. 1.6 20 km WSW of Dutch Harbor, Alaska 09:15 UTC
3. 1.7 Fox Islands, Aleutian Islands, Alaska 04:05 UTC
4. 1.7 8 km ENE of Unalaska, Alaska 13:04 UTC
5. 2.6 Fox Islands, Aleutian Islands, Alaska 15:29 UTC
6. 2.6 7 km SW of Akutan, Alaska 07:06 UTC
7. 2.2 Fox Islands, Aleutian Islands, Alaska 15:08 UTC
8. 2.3 Fox Islands, Aleutian Islands, Alaska 22:29 UTC
9. 1.5 6 km WSW of Unalaska, Alaska 22:05 UTC
10. 1.7 Fox Islands, Aleutian Islands, Alaska 13:12 UTC
11. 1.5 5 km WSW of Dutch Harbor, Alaska 14:55 UTC
12. 1.6 4 km NNE of Dutch Harbor, Alaska 16:18 UTC
13. 1.6 Fox Islands, Aleutian Islands, Alaska 01:25 UTC
14. 2.7 9 km ENE of Dutch Harbor, Alaska 16:56 UTC
15. 1.6 9 km NE of Dutch Harbor, Alaska 16:47 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 14:49 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.