131 km SSE of Perryville, 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 120 km (75 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 7.8 on 2020-07-22 — about 180,000 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

1. 6.6 104 km SSE of Perryville, Alaska · 28 km N of this epicentre Nov 11, 1938
2. 6.5 94 km ESE of Sand Point, Alaska · 42 km WNW of this epicentre Feb 14, 1983
3. 5.9 113 km SE of Sand Point, Alaska · 45 km WSW of this epicentre Jun 7, 1917
4. 5.9 90 km ESE of Sand Point, Alaska · 47 km WNW of this epicentre Feb 14, 1983
5. 5.4 139 km SSE of Perryville, Alaska · 27 km E of this epicentre Jan 1, 1991

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 54.7709, -158.5893. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.5 138 km SSE of Perryville, Alaska 22:30 UTC
2. 2.4 123 km SSE of Perryville, Alaska 21:12 UTC
3. 2.4 149 km SSE of Perryville, Alaska 03:38 UTC
4. 2.5 150 km SSE of Perryville, Alaska 03:36 UTC
5. 3.3 116 km S of Perryville, Alaska 06:36 UTC
6. 1.9 94 km ESE of Sand Point, Alaska 08:12 UTC
7. 3.0 173 km SSE of Perryville, Alaska 08:01 UTC
8. 1.9 89 km S of Perryville, Alaska 13:24 UTC
9. 3.0 129 km SE of Sand Point, Alaska 09:51 UTC
10. 3.1 112 km S of Perryville, Alaska 15:25 UTC
11. 3.0 132 km SSE of Perryville, Alaska 17:04 UTC
12. 2.2 107 km S of Perryville, Alaska 06:52 UTC
13. 3.1 122 km SSE of Perryville, Alaska 13:10 UTC
14. 3.0 145 km SSE of Perryville, Alaska 01:43 UTC
15. 2.3 113 km SSE of Perryville, Alaska 16:57 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 17:05 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.