27 km E of Chignik, 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 7.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 2,000,000× the energy of this one
2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
3. Around the size people start to feel M 3.0 130× the energy of this one
4. This earthquake M 1.6 about 7.6 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 4.1 on 2017-03-18 — about 5,600 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

1. 6.5 60 km ENE of Chignik, Alaska · 40 km NE of this epicentre Sep 28, 1941
2. 6.4 61 km ENE of Chignik, Alaska · 44 km NE of this epicentre Jan 1, 1963
3. 6.4 77 km ESE of Chignik, Alaska · 50 km ESE of this epicentre Mar 24, 1972
4. 5.8 46 km S of Chignik, Alaska · 47 km SSW of this epicentre Feb 21, 1972
5. 5.7 71 km ENE of Chignik, Alaska · 50 km NE of this epicentre Feb 7, 1967

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 56.2524, -157.9678. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 1.6 64 km ENE of Chignik, Alaska 11:11 UTC
2. 1.6 46 km ENE of Chignik, Alaska 08:04 UTC
3. 2.1 41 km ENE of Chignik, Alaska 01:16 UTC
4. 1.9 42 km ESE of Chignik, Alaska 07:35 UTC
5. 2.0 36 km SE of Chignik, Alaska 07:10 UTC
6. 2.4 36 km SSE of Chignik, Alaska 03:48 UTC
7. 2.5 63 km NE of Chignik, Alaska 21:21 UTC
8. 2.2 31 km N of Chignik, Alaska 03:01 UTC
9. 1.9 47 km SSE of Chignik, Alaska 13:05 UTC
10. 2.6 53 km ESE of Chignik, Alaska 10:39 UTC
11. 1.7 67 km ESE of Chignik, Alaska 10:15 UTC
12. 2.3 72 km ESE of Chignik, Alaska 23:28 UTC
13. 2.1 71 km SE of Chignik, Alaska 14:15 UTC
14. 2.2 61 km ENE of Chignik, Alaska 04:44 UTC
15. 2.2 43 km S of Chignik, Alaska 19:01 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 01:54 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.