287 km ESE of Chiniak, 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 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 250,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
4. This earthquake M 3.1 about 1,300 lb of TNT
5. Around the size people start to feel M 3.0 this one released 1.4× 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 56.5845, -147.9294. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 3.1 278 km ESE of Chiniak, Alaska 06:53 UTC
2. 5.5 276 km ESE of Chiniak, Alaska 08:14 UTC
3. 3.1 296 km ESE of Chiniak, Alaska 12:40 UTC
4. 3.1 283 km ESE of Chiniak, Alaska 21:34 UTC
5. 3.1 297 km ESE of Chiniak, Alaska 13:48 UTC
6. 3.4 277 km ESE of Chiniak, Alaska 05:12 UTC
7. 2.8 281 km ESE of Chiniak, Alaska 02:00 UTC
8. 3.6 295 km ESE of Chiniak, Alaska 00:14 UTC
9. 3.0 296 km ESE of Chiniak, Alaska 13:58 UTC
10. 2.9 265 km ESE of Chiniak, Alaska 02:47 UTC
11. 3.0 273 km ESE of Chiniak, Alaska 22:52 UTC
12. 3.2 Gulf of Alaska 15:53 UTC
13. 3.5 275 km ESE of Chiniak, Alaska 09:55 UTC
14. 3.4 278 km ESE of Chiniak, Alaska 09:02 UTC
15. 2.8 254 km ESE of Chiniak, Alaska 20:08 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 03:34 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 5.3 on 2018-01-23 — it released about 2,000 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.