south of 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 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 16,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 710× the energy of this one
3. Magna, Utah 2020 M 5.7 500× the energy of this one
4. This earthquake M 3.9 about 11 tons of TNT
5. Around the size people start to feel M 3.0 this one released 22× 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 52.8439, -162.1708. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.8 263 km SSE of False Pass, Alaska 00:31 UTC
2. 2.0 222 km S of King Cove, Alaska 13:56 UTC
3. 3.2 211 km S of King Cove, Alaska 15:05 UTC
4. 2.7 199 km SSE of False Pass, Alaska 12:31 UTC
5. 2.7 230 km SSE of False Pass, Alaska 06:52 UTC
6. 3.1 217 km S of King Cove, Alaska 14:51 UTC
7. 3.1 265 km SSE of False Pass, Alaska 23:00 UTC
8. 3.1 219 km S of King Cove, Alaska 00:35 UTC
9. 2.6 204 km SSE of False Pass, Alaska 22:28 UTC
10. 2.9 207 km SSE of False Pass, Alaska 07:54 UTC
11. 2.6 224 km SSE of False Pass, Alaska 21:27 UTC
12. 2.6 226 km SSE of False Pass, Alaska 12:32 UTC
13. 3.2 220 km SSE of False Pass, Alaska 01:17 UTC
14. 2.7 202 km SSE of False Pass, Alaska 13:26 UTC
15. 2.8 225 km SSE of False Pass, Alaska 22:29 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 19:24 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 4.9 on 2020-11-04 — it released about 32 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.