138 km SE of Akutan, Alaska

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 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 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 5.1 on 2017-05-24 — about 16 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

1. 6.2 136 km SE of Akutan, Alaska · 46 km NE of this epicentre Apr 1, 1946
2. 6.2 156 km SE of Akutan, Alaska · 35 km E of this epicentre Nov 12, 1946
3. 5.4 112 km SE of Akutan, Alaska · 35 km N of this epicentre Apr 4, 1993
4. 5.4 149 km SE of Akutan, Alaska · 14 km ESE of this epicentre Dec 1, 1998
5. 5.2 121 km SE of Akutan, Alaska · 27 km N of this epicentre Dec 28, 2005

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 53.1316, -164.5341. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.6 139 km SE of Akutan, Alaska 06:48 UTC
2. 3.2 120 km SE of Akutan, Alaska 16:02 UTC
3. 2.4 139 km SE of Akutan, Alaska 10:23 UTC
4. 2.4 129 km SE of Akutan, Alaska 22:08 UTC
5. 2.7 143 km SSE of Akutan, Alaska 20:42 UTC
6. 3.5 128 km SE of Akutan, Alaska 20:37 UTC
7. 3.1 133 km SE of Akutan, Alaska 19:08 UTC
8. 2.6 141 km SSE of Akutan, Alaska 18:26 UTC
9. 3.0 134 km SE of Akutan, Alaska 18:12 UTC
10. 2.8 128 km SE of Akutan, Alaska 11:51 UTC
11. 3.1 135 km SE of Akutan, Alaska 06:09 UTC
12. 3.6 139 km SE of Akutan, Alaska 13:25 UTC
13. 2.5 135 km SE of Akutan, Alaska 19:24 UTC
14. 2.8 179 km SE of Akutan, Alaska 12:56 UTC
15. 2.0 97 km SE of Akutan, Alaska 07:09 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 13:45 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.