Earthquake near Dutch Harbor, AK

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 2 km (1 mi) from the epicentre. In Dutch Harbor, 8 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.

Earthquakes near other towns within 30 km: Unalaska.

How big was it?

This earthquake released about 5.6 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 2,700,000× the energy of this one
2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
3. Around the size people start to feel M 3.0 170× the energy of this one
4. This earthquake M 1.5 about 5.6 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 4.8 on 2020-03-30 — about 86,000 times the energy of this one.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

1. 6.2 36 km ESE of Unalaska, Alaska · 41 km SE of this epicentre Dec 9, 1942
2. 5.9 27 km WNW of Dutch Harbor, Alaska · 26 km W of this epicentre Apr 21, 1972
3. 5.9 13 km NE of Dutch Harbor, Alaska · 9 km E of this epicentre Sep 1, 2006
4. 5.4 26 km WSW of Dutch Harbor, Alaska · 30 km WSW of this epicentre Oct 20, 1991
5. 5.3 22 km ENE of Dutch Harbor, Alaska · 19 km E of this epicentre Dec 22, 1988

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 53.9577, -166.5292. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 3.7 29 km E of Unalaska, Alaska 14:23 UTC
2. 1.6 42 km SW of Unalaska, Alaska 11:10 UTC
3. 2.5 32 km SSW of Unalaska, Alaska 06:20 UTC
4. 1.5 16 km WSW of Akutan, Alaska 03:13 UTC
5. 2.2 40 km SE of Unalaska, Alaska 20:40 UTC
6. 2.0 19 km WSW of Akutan, Alaska 06:37 UTC
7. 1.6 41 km SW of Unalaska, Alaska 09:46 UTC
8. 2.0 35 km ESE of Unalaska, Alaska 16:15 UTC
9. 1.8 24 km S of Unalaska, Alaska 20:25 UTC
10. 1.6 29 km S of Unalaska, Alaska 10:36 UTC
11. 3.5 39 km SSE of Unalaska, Alaska 01:50 UTC
12. 1.5 19 km ESE of Unalaska, Alaska 23:23 UTC
13. 1.6 23 km S of Unalaska, Alaska 05:31 UTC
14. 1.6 23 km S of Unalaska, Alaska 05:31 UTC
15. 1.9 17 km W of Akutan, Alaska 11:04 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 23:44 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.