QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

Earthquake near Carolina, PR

No earthquake was likely felt in Carolina in the 24 hours to 5:55 pm AST (21:55 UTC). The last one was M 4.1, 81 km (50 mi) SE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Carolina

This page: a magnitude 3.4 earthquake was recorded 49 km (31 mi) northeast of Carolina, PR, at 9:28 pm AST on 31 October 2025 (01:28 UTC), 69 km deep.

USGS: 32 km NNE of Luquillo, Puerto Rico

58 km (36 mi) ENE of San Juan, PR · 50 km (31 mi) ENE of Carolina, PR

9:28 pm AST, Oct 31, 2025 · · 69 km deep · released about 1.6 tons of TNT

Every earthquake near Carolina Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Fajardo Municipio 28 kmLuquillo Municipio 33 kmRío Grande Municipio 37 kmCeiba Municipio 43 kmLoíza Municipio 44 kmCulebra Municipio 44 kmCanóvanas Municipio 47 kmCarolina Municipio 49 kmNaguabo Municipio 50 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
9:28 pm AST on 31 October 2025 ()
Where
49 km (31 mi) northeast of Carolina, PR · earthquakes near Carolina
Magnitude
M 3.4 (md)
Depth
69 km below the surface
Felt
no reports yet
Nearest
Fajardo Municipio, 28 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 288 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 it was probably too small to be felt, even directly above it. In Carolina, 49 km away, the estimate is intensity II (weak). 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 1.6 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 110,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,700× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,300× the energy of this one
  4. This earthquake M 3.4 about 1.6 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 3.3× 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.8 on 2021-03-09 — about 150 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.0 73 km NNE of Vieques, Puerto Rico · 41 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 18.6363, -65.5732. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fajardo Municipio, PR 28 km (17 mi) S earthquakes near Fajardo Municipio
Luquillo Municipio, PR 33 km (21 mi) SSW earthquakes near Luquillo Municipio
Río Grande Municipio, PR 37 km (23 mi) SW earthquakes near Río Grande Municipio
Ceiba Municipio, PR 43 km (27 mi) S earthquakes near Ceiba Municipio
Loíza Municipio, PR 44 km (28 mi) WSW earthquakes near Loíza Municipio
Culebra Municipio, PR 44 km (28 mi) SE earthquakes near Culebra 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. 3.6 76 km N of Culebra, Puerto Rico
  2. 3.3 76 km N of Culebra, Puerto Rico
  3. 3.1 55 km NNE of San Juan, Puerto Rico
  4. 3.0 60 km N of Loíza, Puerto Rico
  5. 2.9 23 km NNE of Luquillo, Puerto Rico
  6. 3.3 41 km N of Culebra, Puerto Rico
  7. 3.2 48 km NNW of Charlotte Amalie, U.S. Virgin Islands
  8. 3.2 51 km NNE of Vieques, Puerto Rico
  9. 3.1 73 km N of Culebra, Puerto Rico
  10. 3.3 20 km NE of Luquillo, Puerto Rico
  11. 2.5 27 km NNE of Vieques, Puerto Rico
  12. 3.2 76 km N of Culebra, Puerto Rico
  13. 3.4 49 km N of Suárez, Puerto Rico
  14. 3.1 59 km N of Loíza, Puerto Rico
  15. 3.8 30 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.