QuakeIndex

Earthquake · reviewed by a seismologist

M 4.4ml

89 km N of Culebra, Puerto Rico

Yes. A magnitude 4.4 earthquake was recorded 89 km N of Culebra, Puerto Rico, at 3:06 am AST on 28 December 2019 (07:06 UTC), 17 km deep. 5 people have reported feeling it to USGS.

· 17 km deep · released about 60 tons of TNT

10 km30 km60 km120 km N Culebra Municipio 87 kmFajardo Municipio 87 kmLuquillo Municipio 95 kmRío Grande Municipio 99 kmCeiba Municipio 102 kmLoíza Municipio 103 kmCarolina Municipio 108 kmCanóvanas Municipio 108 kmVieques Municipio 111 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 4.4 (ml)
Depth
17 km below the surface
Felt
5 reports · strongest reported intensity III
Nearest
Culebra Municipio, 87 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2433 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 129 km (80 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 60 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 2,800× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 130× the energy of this one
  3. Magna, Utah 2020 M 5.7 89× the energy of this one
  4. This earthquake M 4.4 about 60 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 130× 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 4.5 on 2018-02-09 — about 1.4 times the energy of this one.

Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.1 91 km N of Charlotte Amalie, U.S. Virgin Islands · 46 km E of this epicentre
  2. 6.0 112 km N of Charlotte Amalie, U.S. Virgin Islands · 44 km NE of this epicentre
  3. 5.6 112 km N of Charlotte Amalie, U.S. Virgin Islands · 48 km NE of this epicentre
  4. 5.1 107 km N of Charlotte Amalie, U.S. Virgin Islands · 40 km NE of this epicentre
  5. 5.1 122 km NNE of Vieques, Puerto Rico · 34 km N 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 19.1090, -65.2656. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Culebra Municipio, PR 87 km (54 mi) S earthquakes near Culebra Municipio
Fajardo Municipio, PR 87 km (54 mi) SSW earthquakes near Fajardo Municipio
Luquillo Municipio, PR 95 km (59 mi) SSW earthquakes near Luquillo Municipio
Río Grande Municipio, PR 99 km (61 mi) SW earthquakes near Río Grande Municipio
Ceiba Municipio, PR 102 km (64 mi) SSW earthquakes near Ceiba Municipio
Loíza Municipio, PR 103 km (64 mi) SW earthquakes near Loíza Municipio

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

Aftershocks so far

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

  1. 3.3 75.2 km SSW of Luquillo, Puerto Rico
  2. 3.5 73 km N of Culebra, Puerto Rico
  3. 3.4 81 km NNE of Luquillo, Puerto Rico
  4. 3.3 76 km NNE of Luquillo, Puerto Rico
  5. 3.4 74 km NNE of Luquillo, Puerto Rico
  6. 3.4 83 km NNE of Luquillo, Puerto Rico
  7. 3.3 79 km NNE of Luquillo, Puerto Rico
  8. 3.6 69 km NNW of Charlotte Amalie, U.S. Virgin Islands
  9. 3.6 75 km N of Charlotte Amalie, U.S. Virgin Islands
  10. 2.9 44 km NNW of Charlotte Amalie, U.S. Virgin Islands
  11. 3.6 63 km NNW of Charlotte Amalie, U.S. Virgin Islands
  12. 3.6 95 km N of Charlotte Amalie, U.S. Virgin Islands
  13. 3.5 74 km NNW of Charlotte Amalie, U.S. Virgin Islands
  14. 3.7 72 km NNW of Charlotte Amalie, U.S. Virgin Islands
  15. 2.6 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.

On USGS

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