QuakeIndex

Earthquake · reviewed by a seismologist

M 3.8md

104 km N of Culebra, Puerto Rico

Yes. A magnitude 3.8 earthquake was recorded 104 km N of Culebra, Puerto Rico, at 3:26 pm AST on 5 July 2020 (19:26 UTC), 31 km deep.

· 31 km deep · released about 6.4 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Fajardo Municipio 101 kmCulebra Municipio 102 kmLuquillo Municipio 107 kmRío Grande Municipio 110 kmLoíza Municipio 112 kmCeiba Municipio 116 kmCarolina Municipio 118 kmCanóvanas Municipio 120 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 3.8 (md)
Depth
31 km below the surface
Felt
no reports yet
Nearest
Fajardo Municipio, 101 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2252 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 73 km (45 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 6.4 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 27,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,200× the energy of this one
  3. Magna, Utah 2020 M 5.7 840× the energy of this one
  4. This earthquake M 3.8 about 6.4 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 13× 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 53 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 · 50 km E of this epicentre
  2. 6.0 112 km N of Charlotte Amalie, U.S. Virgin Islands · 40 km ENE of this epicentre
  3. 5.6 112 km N of Charlotte Amalie, U.S. Virgin Islands · 45 km ENE of this epicentre
  4. 5.1 107 km N of Charlotte Amalie, U.S. Virgin Islands · 36 km ENE of this epicentre
  5. 5.1 122 km NNE of Vieques, Puerto Rico · 18 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 19.2483, -65.2961. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fajardo Municipio, PR 101 km (63 mi) SSW earthquakes near Fajardo Municipio
Culebra Municipio, PR 102 km (64 mi) S earthquakes near Culebra Municipio
Luquillo Municipio, PR 107 km (67 mi) SSW earthquakes near Luquillo Municipio
Río Grande Municipio, PR 110 km (69 mi) SSW earthquakes near Río Grande Municipio
Loíza Municipio, PR 112 km (70 mi) SW earthquakes near Loíza Municipio
Ceiba Municipio, PR 116 km (72 mi) SSW earthquakes near Ceiba Municipio

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

Aftershocks so far

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

  1. 3.4 104 km N of Charlotte Amalie, U.S. Virgin Islands
  2. 3.4 91 km N of Charlotte Amalie, U.S. Virgin Islands
  3. 3.4 86 km N of Charlotte Amalie, U.S. Virgin Islands
  4. 3.2 77 km NNE of Vieques, Puerto Rico
  5. 3.4 102 km N of Charlotte Amalie, U.S. Virgin Islands
  6. 3.6 86 km N of Charlotte Amalie, U.S. Virgin Islands
  7. 3.5 90 km N of Charlotte Amalie, U.S. Virgin Islands
  8. 3.2 74 km NNE of Vieques, Puerto Rico
  9. 3.4 98 km NNW of Charlotte Amalie, U.S. Virgin Islands
  10. 3.4 102 km N of Charlotte Amalie, U.S. Virgin Islands
  11. 3.4 113 km N of Suárez, Puerto Rico
  12. 3.6 145 km NNE of Vieques, Puerto Rico
  13. 3.7 133 km NNW of Charlotte Amalie, U.S. Virgin Islands
  14. 3.4 106 km NNW of Charlotte Amalie, U.S. Virgin Islands
  15. 2.9 84 km NNE of Luquillo, Puerto Rico

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.