149 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 54.7909, -157.8481. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.3 south of Alaska 05:00 UTC
2. 2.4 123 km SSE of Perryville, Alaska 21:12 UTC
3. 2.6 105 km SE of Perryville, Alaska 08:13 UTC
4. 2.7 147 km SE of Perryville, Alaska 14:27 UTC
5. 2.4 143 km SE of Perryville, Alaska 08:16 UTC
6. 2.3 138 km SE of Perryville, Alaska 02:00 UTC
7. 2.4 133 km SE of Perryville, Alaska 00:51 UTC
8. 2.5 135 km SE of Perryville, Alaska 14:47 UTC
9. 2.9 130 km SE of Perryville, Alaska 23:20 UTC
10. 2.4 149 km SSE of Perryville, Alaska 03:38 UTC
11. 2.5 150 km SSE of Perryville, Alaska 03:36 UTC
12. 3.0 111 km SE of Perryville, Alaska 09:02 UTC
13. 3.0 173 km SSE of Perryville, Alaska 08:01 UTC
14. 2.1 132 km SE of Perryville, Alaska 13:56 UTC
15. 2.5 136 km SE of Perryville, Alaska 13:17 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 13:24 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 6.9 on 2021-08-14 — it released about 22,000 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.