153 km NNE of Vieques, Puerto Rico

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 46 km (29 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 1.6 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 110,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 4,700× the energy of this one
3. Magna, Utah 2020 M 5.7 3,300× the energy of this one
4. This earthquake M 3.4 about 1.6 tons of TNT
5. Around the size people start to feel M 3.0 this one released 3.3× 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 4.9 on 2018-11-14 — about 210 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

1. 5.1 122 km NNE of Vieques, Puerto Rico · 37 km S of this epicentre Sep 6, 2004

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 19.7421, -65.3768. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 3.6 152 km NNE of Vieques, Puerto Rico 06:54 UTC
2. 3.5 118 km NNE of Vieques, Puerto Rico 01:21 UTC
3. 3.5 Puerto Rico region 01:05 UTC
4. 2.9 127 km NNE of Vieques, Puerto Rico 14:53 UTC
5. 3.3 163 km NNE of Vieques, Puerto Rico 09:47 UTC
6. 2.7 137 km NNE of Vieques, Puerto Rico 08:55 UTC
7. 2.4 117 km NNE of Suárez, Puerto Rico 08:00 UTC
8. 2.4 117 km NNE of Vieques, Puerto Rico 07:20 UTC
9. 2.9 153 km NNE of Vieques, Puerto Rico 05:10 UTC
10. 3.3 144 km NNE of Vieques, Puerto Rico 04:17 UTC
11. 2.6 138 km N of Charlotte Amalie, U.S. Virgin Islands 04:13 UTC
12. 3.8 152 km NNW of Charlotte Amalie, U.S. Virgin Islands 04:01 UTC
13. 3.0 Puerto Rico region 11:22 UTC
14. 2.6 141 km NNE of Vieques, Puerto Rico 21:47 UTC
15. 2.8 123 km NNW of Charlotte Amalie, U.S. Virgin Islands 20:31 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 21:29 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.