133 km SSE of Perryville, Alaska

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

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.

Where

Epicentre 54.8231, -158.2420. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.3 137 km SE of Perryville, Alaska 21:52 UTC
2. 2.3 114 km SSE of Perryville, Alaska 21:12 UTC
3. 2.6 104 km SSE of Perryville, Alaska 19:14 UTC
4. 2.5 119 km SE of Perryville, Alaska 16:26 UTC
5. 1.9 120 km SE of Perryville, Alaska 16:20 UTC
6. 2.3 143 km SE of Perryville, Alaska 15:19 UTC
7. 2.5 116 km SE of Perryville, Alaska 08:29 UTC
8. 2.5 141 km SE of Perryville, Alaska 07:34 UTC
9. 2.7 129 km SSE of Perryville, Alaska 05:48 UTC
10. 2.8 141 km SSE of Perryville, Alaska 03:30 UTC
11. 2.7 126 km SSE of Perryville, Alaska 03:18 UTC
12. 2.1 123 km SSE of Perryville, Alaska 03:11 UTC
13. 2.1 135 km SE of Perryville, Alaska 18:28 UTC
14. 2.7 137 km SSE of Perryville, Alaska 14:30 UTC
15. 3.7 140 km SE of Perryville, Alaska 14:20 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 14:00 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 4,000,000 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.