QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9md

Virgin Islands

· 49 km deep · released about 10 tons of TNT

10 km30 km60 km120 km N Culebra Municipio 83 kmFajardo Municipio 103 kmVieques Municipio 108 kmCeiba Municipio 114 kmLuquillo Municipio 115 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 3.9 (md)
Depth
49 km below the surface
Felt
no reports yet
Nearest
Culebra Municipio, 83 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1584 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

How big was it?

This earthquake released about 10 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 17,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 760× the energy of this one
  3. Magna, Utah 2020 M 5.7 540× the energy of this one
  4. This earthquake M 3.9 about 10 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 21× 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.

Where

Epicentre 18.8268, -64.7276. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Culebra Municipio, PR 83 km (51 mi) NE of here earthquakes near Culebra Municipio
Fajardo Municipio, PR 103 km (64 mi) ENE of here earthquakes near Fajardo Municipio
Vieques Municipio, PR 108 km (67 mi) NE of here earthquakes near Vieques Municipio
Ceiba Municipio, PR 114 km (71 mi) NE of here earthquakes near Ceiba Municipio
Luquillo Municipio, PR 115 km (72 mi) ENE of here earthquakes near Luquillo Municipio
Río Grande Municipio, PR 123 km (77 mi) ENE of here earthquakes near Río Grande Municipio

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

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

  1. 3.4 70 km NNW of Charlotte Amalie, U.S. Virgin Islands
  2. 3.1 74 km NNW of Charlotte Amalie, U.S. Virgin Islands
  3. 3.4 94 km N of Cruz Bay, U.S. Virgin Islands
  4. 3.0 76 km N of Charlotte Amalie, U.S. Virgin Islands
  5. 3.4 82 km NE of Cruz Bay, U.S. Virgin Islands
  6. 3.7 95 km NNE of Cruz Bay, U.S. Virgin Islands
  7. 3.4 81 km N of Charlotte Amalie, U.S. Virgin Islands
  8. 3.9 Puerto Rico region
  9. 3.7 70 km NNE of Cruz Bay, U.S. Virgin Islands
  10. 3.5 32 km NNW of Charlotte Amalie, U.S. Virgin Islands
  11. 3.5 76 km NE of Cruz Bay, U.S. Virgin Islands
  12. 3.6 87 km NNE of Cruz Bay, U.S. Virgin Islands
  13. 3.7 101 km NNE of Cruz Bay, U.S. Virgin Islands
  14. 3.0 10 km NNW of Cruz Bay, U.S. Virgin Islands
  15. 3.2 66 km NNW of Charlotte Amalie, U.S. Virgin Islands

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 5.0 on 2021-02-06 — it released about 46 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.