QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

Earthquake near San Juan, PR

No earthquake was likely felt in San Juan in the 24 hours to 9:34 am AST (13:34 UTC). The last one was M 4.1, 99 km (62 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 San Juan

This page: a magnitude 3.4 earthquake was recorded 47 km (29 mi) northeast of San Juan, PR, at 9:06 am AST on 18 March 2025 (13:06 UTC), 42 km deep.

USGS: 33 km NNE of Vieques, Puerto Rico

48 km (30 mi) NE of San Juan, PR · 42 km (26 mi) NE of Carolina, PR

9:06 am AST, Mar 18, 2025 · · 42 km deep · released about 2.1 tons of TNT

Every earthquake near San Juan Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Loíza Municipio 36 kmRío Grande Municipio 38 kmLuquillo Municipio 39 kmFajardo Municipio 40 kmCarolina Municipio 43 kmCanóvanas Municipio 45 kmSan Juan Municipio 47 kmTrujillo Alto Municipio 50 kmCataño Municipio 52 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
9:06 am AST on 18 March 2025 ()
Where
47 km (29 mi) northeast of San Juan, PR · earthquakes near San Juan
Magnitude
M 3.4 (md)
Depth
42 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 36 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 543 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 42 km (26 mi) from the epicentre. In San Juan, 47 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.

Likely felt in: Loíza 35 km, intensity II · Luquillo 38 km, intensity II · Río Grande 38 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 2.1 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 80,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 3,600× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,500× the energy of this one
  4. This earthquake M 3.4 about 2.1 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4.4× 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 110 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 NE 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 18.7155, -65.7460. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Loíza Municipio, PR 36 km (23 mi) SW earthquakes near Loíza Municipio
Río Grande Municipio, PR 38 km (24 mi) S earthquakes near Río Grande Municipio
Luquillo Municipio, PR 39 km (24 mi) S earthquakes near Luquillo Municipio
Fajardo Municipio, PR 40 km (25 mi) SSE earthquakes near Fajardo Municipio
Carolina Municipio, PR 43 km (26 mi) SSW earthquakes near Carolina Municipio
Canóvanas Municipio, PR 45 km (28 mi) SSW earthquakes near Canóvanas Municipio

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

Aftershocks so far

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

  1. 3.2 52 km N of Culebra, Puerto Rico
  2. 3.1 56 km N of San Juan, Puerto Rico
  3. 3.2 49 km N of Culebra, Puerto Rico
  4. 3.2 67 km N of Culebra, Puerto Rico
  5. 3.5 12 km NNE of Fajardo, Puerto Rico
  6. 3.3 59 km N of Culebra, Puerto Rico
  7. 3.5 66 km N of Culebra, Puerto Rico
  8. 3.1 46 km N of San Juan, Puerto Rico
  9. 3.2 24 km NE of Luquillo, Puerto Rico
  10. 3.5 9 km NNW of San Juan, Puerto Rico
  11. 3.2 56 km NNW of Culebra, Puerto Rico
  12. 2.9 42 km N of Loíza, Puerto Rico
  13. 3.6 1 km ESE of Carolina, Puerto Rico
  14. 3.6 70 km NNE of Luquillo, Puerto Rico
  15. 3.4 71 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.