142 km NNE of Cruz Bay, U.S. Virgin Islands

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 33 km (21 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 4.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.7 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 35,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 1,600× the energy of this one
3. Magna, Utah 2020 M 5.7 1,100× the energy of this one
4. This earthquake M 3.7 about 4.8 tons of TNT
5. Around the size people start to feel M 3.0 this one released 10× 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 5.0 on 2019-10-06 — about 86 times the energy of this one.

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

1. 6.2 131 km NNE of Cruz Bay, U.S. Virgin Islands · 12 km SW of this epicentre Sep 6, 1919
2. 5.3 97 km N of Cruz Bay, U.S. Virgin Islands · 47 km SSW of this epicentre Dec 19, 2007
3. 5.2 99 km N of Cruz Bay, U.S. Virgin Islands · 47 km SW of this epicentre Dec 28, 2007
4. 5.1 98 km NNE of Cruz Bay, U.S. Virgin Islands · 44 km SSW of this epicentre Jan 22, 1979
5. 5.0 127 km NNE of Cruz Bay, U.S. Virgin Islands · 17 km SW of this epicentre Jan 13, 1993

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 19.5686, -64.4240. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 3.2 108 km N of Cruz Bay, U.S. Virgin Islands 17:40 UTC
2. 3.3 106 km NNE of Cruz Bay, U.S. Virgin Islands 01:53 UTC
3. 4.0 125 km NNE of Cruz Bay, U.S. Virgin Islands 19:17 UTC
4. 3.8 114 km N of Cruz Bay, U.S. Virgin Islands 08:59 UTC
5. 3.6 139 km N of Cruz Bay, U.S. Virgin Islands 21:41 UTC
6. 3.7 107 km NNE of Cruz Bay, U.S. Virgin Islands 06:29 UTC
7. 3.9 150 km N of Cruz Bay, U.S. Virgin Islands 08:57 UTC
8. 3.6 144 km N of Charlotte Amalie, U.S. Virgin Islands 09:06 UTC
9. 3.6 110 km NNE of Cruz Bay, U.S. Virgin Islands 16:59 UTC
10. 3.8 162 km N of Cruz Bay, U.S. Virgin Islands 21:06 UTC
11. 3.0 123 km NNE of Cruz Bay, U.S. Virgin Islands 05:14 UTC
12. 3.6 97 km N of Cruz Bay, U.S. Virgin Islands 07:10 UTC
13. 3.7 111 km NNE of Cruz Bay, U.S. Virgin Islands 00:46 UTC
14. 3.8 151 km NNE of Cruz Bay, U.S. Virgin Islands 23:41 UTC
15. 4.3 129 km NNE of Cruz Bay, U.S. Virgin Islands 07:12 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 20:41 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.