21 km S of Kokhanok, Alaska

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 7 km (4 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 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
3. Around the size people start to feel M 3.0 180× the energy of this one
4. This earthquake M 1.5 about 5.4 lb of TNT

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 4.5 on 2020-02-12 — about 32,000 times the energy of this one.

Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:

1. 6.0 62 km SSE of Kokhanok, Alaska · 42 km SSE of this epicentre May 4, 1937
2. 5.6 62 km SE of Kokhanok, Alaska · 45 km SE of this epicentre Mar 23, 1984
3. 5.2 31 km SSE of Pope-Vannoy Landing, Alaska · 32 km ENE of this epicentre Mar 10, 2013
4. 5.0 52 km S of Kokhanok, Alaska · 31 km S of this epicentre Mar 21, 1981

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 59.2440, -154.7486. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.2 53 km SE of Kokhanok, Alaska 15:00 UTC
2. 3.0 56 km SSE of Kokhanok, Alaska 12:50 UTC
3. 2.1 51 km SSE of Kokhanok, Alaska 12:48 UTC
4. 1.9 56 km SSE of Kokhanok, Alaska 04:49 UTC
5. 1.9 47 km SE of Kokhanok, Alaska 12:44 UTC
6. 2.3 70 km S of Kokhanok, Alaska 13:44 UTC
7. 1.6 22 km SSE of Pope-Vannoy Landing, Alaska 01:58 UTC
8. 4.3 62 km SSE of Kokhanok, Alaska 02:57 UTC
9. 3.7 54 km SSE of Kokhanok, Alaska 10:27 UTC
10. 2.2 66 km SSE of Kokhanok, Alaska 23:13 UTC
11. 1.7 64 km SSE of Kokhanok, Alaska 03:55 UTC
12. 2.2 56 km SSE of Kokhanok, Alaska 21:51 UTC
13. 1.5 13 km S of Newhalen, Alaska 15:20 UTC
14. 1.5 15 km N of Kokhanok, Alaska 11:40 UTC
15. 2.2 49 km SSE of Kokhanok, Alaska 07:24 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 11:59 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.