145 km N of Charlotte Amalie, 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 83 km (52 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 7.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.8 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 22,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 970× the energy of this one
3. Magna, Utah 2020 M 5.7 680× the energy of this one
4. This earthquake M 3.8 about 7.8 tons of TNT
5. Around the size people start to feel M 3.0 this one released 16× 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 53 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. 6.2 131 km NNE of Cruz Bay, U.S. Virgin Islands · 44 km ESE of this epicentre Sep 6, 1919
2. 6.0 112 km N of Charlotte Amalie, U.S. Virgin Islands · 34 km S of this epicentre Oct 17, 2001
3. 5.6 112 km N of Charlotte Amalie, U.S. Virgin Islands · 34 km S of this epicentre Oct 16, 2001
4. 5.1 107 km N of Charlotte Amalie, U.S. Virgin Islands · 39 km SSW of this epicentre May 11, 1996
5. 5.0 122 km N of Charlotte Amalie, U.S. Virgin Islands · 24 km S of this epicentre Mar 19, 1984

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 19.6595, -64.8798. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 3.9 143 km NNE of Vieques, Puerto Rico 07:40 UTC
2. 3.8 141 km NNE of Vieques, Puerto Rico 23:13 UTC
3. 3.6 139 km NNE of Vieques, Puerto Rico 08:29 UTC
4. 3.7 147 km NNE of Vieques, Puerto Rico 06:14 UTC
5. 3.9 119 km N of Charlotte Amalie, U.S. Virgin Islands 08:20 UTC
6. 3.9 139 km N of Cruz Bay, U.S. Virgin Islands 04:01 UTC
7. 3.4 106 km N of Cruz Bay, U.S. Virgin Islands 09:18 UTC
8. 3.2 105 km N of Charlotte Amalie, U.S. Virgin Islands 02:23 UTC
9. 3.0 155 km NNE of Cruz Bay, U.S. Virgin Islands 12:10 UTC
10. 3.2 104 km N of Cruz Bay, U.S. Virgin Islands 21:11 UTC
11. 3.6 Virgin Islands 19:52 UTC
12. 3.7 113 km N of Charlotte Amalie, U.S. Virgin Islands 10:39 UTC
13. 3.5 160 km NNE of Cruz Bay, U.S. Virgin Islands 20:43 UTC
14. 3.6 120 km N of Cruz Bay, U.S. Virgin Islands 20:07 UTC
15. 3.7 161 km N of Cruz Bay, U.S. Virgin Islands 10:17 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 21:24 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.