QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Puerto Rico region

· 14 km deep · released about 1,300 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Loíza Municipio 50 kmFajardo Municipio 50 kmLuquillo Municipio 51 kmRío Grande Municipio 51 kmCarolina Municipio 56 kmCanóvanas Municipio 58 kmSan Juan Municipio 60 kmTrujillo Alto Municipio 63 kmCeiba Municipio 64 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 3.1 (md)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 50 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1039 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 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 270,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 12,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 8,500× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.3× 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.

Where

Epicentre 18.8228, -65.6918. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Loíza Municipio, PR 50 km (31 mi) NNE of here earthquakes near Loíza Municipio
Fajardo Municipio, PR 50 km (31 mi) NNW of here earthquakes near Fajardo Municipio
Luquillo Municipio, PR 51 km (31 mi) N of here earthquakes near Luquillo Municipio
Río Grande Municipio, PR 51 km (32 mi) NNE of here earthquakes near Río Grande Municipio
Carolina Municipio, PR 56 km (35 mi) NNE of here earthquakes near Carolina Municipio
Canóvanas Municipio, PR 58 km (36 mi) NNE of here earthquakes near Canóvanas Municipio

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

Aftershocks so far

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

  1. 3.6 72 km N of Culebra, Puerto Rico
  2. 2.9 20 km NE of Luquillo, Puerto Rico
  3. 3.1 43 km NNE of Luquillo, Puerto Rico
  4. 2.9 34 km N of San Juan, Puerto Rico
  5. 3.2 37 km NNE of Vieques, Puerto Rico
  6. 3.3 64 km N of Culebra, Puerto Rico
  7. 3.6 49 km NNE of Luquillo, Puerto Rico
  8. 3.3 75 km NNE of Luquillo, Puerto Rico
  9. 3.6 90 km NNE of Vieques, Puerto Rico
  10. 3.5 75 km NNE of San Juan, Puerto Rico
  11. 3.4 55 km N of Culebra, Puerto Rico
  12. 3.4 56 km N of Culebra, Puerto Rico
  13. 3.2 59 km N of Culebra, Puerto Rico
  14. 3.4 55 km N of Culebra, Puerto Rico
  15. 3.2 69 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.8 on 2021-03-09 — it released about 380 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.