QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

75 km NNW of Charlotte Amalie, U.S. Virgin Islands

Yes. A magnitude 3.4 earthquake was recorded 75 km NNW of Charlotte Amalie, U.S. Virgin Islands, at 5:16 am AST on 26 December 2021 (09:16 UTC), 23 km deep.

· 23 km deep · released about 1.7 tons of TNT

10 km30 km60 km120 km N Culebra Municipio 79 kmFajardo Municipio 87 kmLuquillo Municipio 97 kmCeiba Municipio 101 kmRío Grande Municipio 103 kmVieques Municipio 105 kmLoíza Municipio 110 kmNaguabo Municipio 112 kmCanóvanas Municipio 113 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 3.4 (md)
Depth
23 km below the surface
Felt
no reports yet
Nearest
Culebra Municipio, 79 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1781 days ago

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 51 km (32 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 1.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 99,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,100× the energy of this one
  4. This earthquake M 3.4 about 1.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 3.6× 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 2021-02-06 — about 270 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.1 91 km N of Charlotte Amalie, U.S. Virgin Islands · 32 km ENE of this epicentre
  2. 6.0 112 km N of Charlotte Amalie, U.S. Virgin Islands · 42 km NNE of this epicentre
  3. 5.9 68 km N of Cruz Bay, U.S. Virgin Islands · 41 km E of this epicentre
  4. 5.6 112 km N of Charlotte Amalie, U.S. Virgin Islands · 44 km NNE of this epicentre
  5. 5.3 78 km NNE of Cruz Bay, U.S. Virgin Islands · 48 km E of this epicentre

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 19.0106, -65.0906. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Culebra Municipio, PR 79 km (49 mi) SSW earthquakes near Culebra Municipio
Fajardo Municipio, PR 87 km (54 mi) SW earthquakes near Fajardo Municipio
Luquillo Municipio, PR 97 km (60 mi) SW earthquakes near Luquillo Municipio
Ceiba Municipio, PR 101 km (63 mi) SSW earthquakes near Ceiba Municipio
Río Grande Municipio, PR 103 km (64 mi) SW earthquakes near Río Grande Municipio
Vieques Municipio, PR 105 km (65 mi) SSW earthquakes near Vieques Municipio

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

Aftershocks so far

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

  1. 3.2 62 km NNW of Charlotte Amalie, U.S. Virgin Islands
  2. 3.9 74 km N of Culebra, Puerto Rico
  3. 3.6 121 km N of Charlotte Amalie, U.S. Virgin Islands
  4. 3.5 61 km N of Culebra, Puerto Rico
  5. 3.2 50 km N of Culebra, Puerto Rico
  6. 3.3 60 km N of Culebra, Puerto Rico
  7. 3.2 73 km NNW of Charlotte Amalie, U.S. Virgin Islands
  8. 3.4 37 km NW of Charlotte Amalie, U.S. Virgin Islands
  9. 3.4 50 km NNW of Charlotte Amalie, U.S. Virgin Islands
  10. 3.9 106 km N of Cruz Bay, U.S. Virgin Islands
  11. 4.1 104 km N of Charlotte Amalie, U.S. Virgin Islands
  12. 3.4 67 km N of Culebra, Puerto Rico
  13. 3.0 38 km NNE of Culebra, Puerto Rico
  14. 3.7 105 km NNW of Charlotte Amalie, U.S. Virgin Islands
  15. 3.4 103 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.

On USGS

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