Earthquake near Akutan, AK

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 57 km (35 mi) from the epicentre. In Akutan, 9 km away, the estimate is intensity III (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: Akutan 9 km, intensity III · Unalaska 50 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1.9 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 89,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 4,000× the energy of this one
3. Magna, Utah 2020 M 5.7 2,800× the energy of this one
4. This earthquake M 3.4 about 1.9 tons of TNT
5. Around the size people start to feel M 3.0 this one released 4× 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 5.4 on 2019-09-14 — about 1,000 times the energy of this one.

Before 2016, the USGS record lists 14 earthquakes of M5 or more within 50 km; the five largest:

1. 7.1 39 km S of Akutan, Alaska · 40 km SSE of this epicentre Mar 22, 1957
2. 6.3 23 km NE of Akutan, Alaska · 29 km NE of this epicentre May 19, 1989
3. 6.2 36 km ESE of Unalaska, Alaska · 48 km SSW of this epicentre Dec 9, 1942
4. 5.9 13 km NE of Dutch Harbor, Alaska · 36 km WSW of this epicentre Sep 1, 2006
5. 5.8 41 km ESE of Akutan, Alaska · 49 km ESE of this epicentre Sep 1, 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 54.1324, -165.9120. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.3 41 km N of Dutch Harbor, Alaska 14:43 UTC
2. 3.0 13 km WSW of Akutan, Alaska 22:39 UTC
3. 1.8 14 km WSW of Akutan, Alaska 01:13 UTC
4. 2.2 17 km S of Akutan, Alaska 09:49 UTC
5. 2.2 31 km N of Akutan, Alaska 13:53 UTC
6. 2.0 25 km NNE of Akutan, Alaska 13:02 UTC
7. 2.8 32 km SE of Akutan, Alaska 08:00 UTC
8. 2.1 25 km E of Akutan, Alaska 00:37 UTC
9. 2.0 14 km ENE of Dutch Harbor, Alaska 09:06 UTC
10. 1.9 18 km ESE of Unalaska, Alaska 00:34 UTC
11. 3.3 23 km E of Akutan, Alaska 18:56 UTC
12. 1.9 43 km NW of Akutan, Alaska 01:47 UTC
13. 1.7 20 km S of Akutan, Alaska 12:29 UTC
14. 1.8 22 km ENE of Unalaska, Alaska 08:38 UTC
15. 1.9 33 km S of Akutan, Alaska 00:39 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 08:13 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.