112 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.

How big was it?

This earthquake released about 15 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.0 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 11,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 500× the energy of this one
3. Magna, Utah 2020 M 5.7 350× the energy of this one
4. This earthquake M 4.0 about 15 tons of TNT
5. Around the size people start to feel M 3.0 this one released 32× 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.

Where

Epicentre 55.0080, -158.3566. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 5.1 122 km SE of Perryville, Alaska 14:57 UTC
2. 2.7 120 km SE of Perryville, Alaska 14:49 UTC
3. 3.5 118 km SSE of Perryville, Alaska 12:39 UTC
4. 2.0 63 km SSE of Perryville, Alaska 05:36 UTC
5. 2.7 125 km SSE of Perryville, Alaska 15:42 UTC
6. 2.1 129 km SE of Perryville, Alaska 14:24 UTC
7. 5.4 140 km SSE of Perryville, Alaska 12:52 UTC
8. 2.8 102 km SSE of Perryville, Alaska 09:18 UTC
9. 2.1 107 km SSE of Perryville, Alaska 06:03 UTC
10. 2.7 102 km SSE of Perryville, Alaska 16:28 UTC
11. 2.2 92 km S of Perryville, Alaska 18:05 UTC
12. 2.4 118 km SSE of Perryville, Alaska 16:27 UTC
13. 2.1 124 km SE of Sand Point, Alaska 22:11 UTC
14. 2.6 153 km SSE of Perryville, Alaska 09:47 UTC
15. 2.6 141 km SSE of Perryville, Alaska 22:00 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 11:12 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 7.8 on 2020-07-22 — it released about 500,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

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.