46 km WNW of False Pass, 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 9 km (6 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 32 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.0 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 470,000× the energy of this one
2. Magna, Utah 2020 M 5.7 330,000× the energy of this one
3. Around the size people start to feel M 3.0 30× the energy of this one
4. This earthquake M 2.0 about 32 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 4.9 on 2017-05-12 — about 21,000 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

1. 5.9 27 km W of False Pass, Alaska · 22 km SE of this epicentre Oct 1, 1951
2. 5.9 14 km NNE of False Pass, Alaska · 49 km E of this epicentre Sep 4, 1971
3. 5.5 66 km NNW of False Pass, Alaska · 47 km NNE of this epicentre Jul 14, 1994
4. 5.1 52 km W of False Pass, Alaska · 20 km SSW of this epicentre Mar 4, 1999
5. 5.0 29 km W of False Pass, Alaska · 22 km SE of this epicentre Apr 13, 1985

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 55.0085, -164.0843. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 1.2 20 km WSW of False Pass, Alaska 12:48 UTC
2. 1.9 30 km SW of False Pass, Alaska 12:31 UTC
3. 1.4 42 km W of False Pass, Alaska 01:57 UTC
4. 1.2 21 km WSW of False Pass, Alaska 22:14 UTC
5. 1.1 21 km WSW of False Pass, Alaska 19:51 UTC
6. 1.3 21 km WSW of False Pass, Alaska 19:47 UTC
7. 1.0 24 km WSW of False Pass, Alaska 19:19 UTC
8. 1.3 59 km WSW of False Pass, Alaska 04:56 UTC
9. 1.1 31 km WSW of False Pass, Alaska 18:57 UTC
10. 1.7 60 km WSW of False Pass, Alaska 23:23 UTC
11. 2.4 29 km WSW of False Pass, Alaska 08:44 UTC
12. 2.2 59 km WSW of False Pass, Alaska 22:54 UTC
13. 3.7 35 km SW of False Pass, Alaska 16:34 UTC
14. 1.8 58 km WSW of False Pass, Alaska 19:25 UTC
15. 1.4 28 km SW of False Pass, Alaska 23:59 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 00:45 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.