33 km ESE of Nikolski, Alaska

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

At this magnitude and depth, people at rest would likely notice it out to about 1 km (1 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 1.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 130,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 5,600× the energy of this one
3. Magna, Utah 2020 M 5.7 4,000× the energy of this one
4. This earthquake M 3.3 about 1.3 tons of TNT
5. Around the size people start to feel M 3.0 this one released 2.8× 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.

For this area

The largest earthquake within 50 km since 2016 was M 6.6 on 2022-01-11 — about 89,000 times the energy of this one.

Before 2016, the USGS record lists 46 earthquakes of M5 or more within 50 km; the five largest:

1. 6.9 80 km E of Nikolski, Alaska · 48 km ENE of this epicentre Mar 24, 1980
2. 6.7 72 km ESE of Nikolski, Alaska · 39 km ESE of this epicentre Jan 2, 1957
3. 6.6 61 km SE of Nikolski, Alaska · 34 km SSE of this epicentre Jan 2, 1957
4. 6.5 45 km SSE of Nikolski, Alaska · 35 km SSW of this epicentre Jan 2, 1957
5. 6.4 71 km SE of Nikolski, Alaska · 46 km SSE of this epicentre Jan 2, 1957

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 52.8658, -168.3710. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.5 45 km SSE of Nikolski, Alaska 14:16 UTC
2. 2.6 51 km SSE of Nikolski, Alaska 22:31 UTC
3. 2.4 30 km SSE of Nikolski, Alaska 20:46 UTC
4. 3.2 65 km SSE of Nikolski, Alaska 00:13 UTC
5. 3.1 49 km ESE of Nikolski, Alaska 05:02 UTC
6. 1.9 65 km ENE of Nikolski, Alaska 21:19 UTC
7. 2.4 47 km SE of Nikolski, Alaska 20:09 UTC
8. 2.1 42 km SE of Nikolski, Alaska 06:29 UTC
9. 2.5 51 km S of Nikolski, Alaska 03:02 UTC
10. 2.0 66 km SSE of Nikolski, Alaska 10:43 UTC
11. 2.0 46 km ESE of Nikolski, Alaska 00:34 UTC
12. 3.2 57 km E of Nikolski, Alaska 20:11 UTC
13. 3.2 58 km ESE of Nikolski, Alaska 12:11 UTC
14. 2.0 48 km ENE of Nikolski, Alaska 11:25 UTC
15. 2.0 31 km SSE of Nikolski, Alaska 20:29 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 12:24 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

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.