QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Earthquake near Arecibo, PR

No earthquake was likely felt in Arecibo in the 24 hours to 7:30 pm AST (23:30 UTC). The last one was M 3.4, 49 km (31 mi) NW, at 9:00 pm AST on 27 October 2026, estimated intensity II (weak) in town. Every earthquake near Arecibo

This page: a magnitude 3.1 earthquake was recorded 42 km (26 mi) north of Arecibo, PR, at 7:30 am AST on 2 September 2025 (11:30 UTC), 20 km deep.

USGS: 41 km N of Arecibo, Puerto Rico

81 km (51 mi) NW of San Juan, PR · 44 km (27 mi) N of Arecibo, PR

7:30 am AST, Sep 2, 2025 · · 20 km deep · released about 1,400 lb of TNT

10 km30 km60 km120 km N Barceloneta Municipio 44 kmArecibo Municipio 46 kmHatillo Municipio 47 kmCamuy Municipio 49 kmManatí Municipio 49 kmQuebradillas Municipio 50 kmVega Baja Municipio 53 kmIsabela Municipio 54 kmFlorida Municipio 55 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
7:30 am AST on 2 September 2025 ()
Where
42 km (26 mi) north of Arecibo, PR · earthquakes near Arecibo
Magnitude
M 3.1 (md)
Depth
20 km below the surface
Felt
no reports yet
Nearest
Barceloneta Municipio, 44 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 357 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 37 km (23 mi) from the epicentre. In Arecibo, 42 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 1,400 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 6.7 240,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,700× the energy of this one
  4. This earthquake M 3.1 about 1,400 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.5× 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 2017-08-18 — about 340 times the energy of this one.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.7 45 km N of San Antonio, Puerto Rico · 47 km W of this epicentre
  2. 6.4 61 km N of Hatillo, Puerto Rico · 26 km NNW of this epicentre
  3. 6.0 81 km N of Isabela, Puerto Rico · 50 km NNW of this epicentre
  4. 5.9 78 km N of Arecibo, Puerto Rico · 37 km N of this epicentre
  5. 5.8 12 km N of Garrochales, Puerto Rico · 34 km SSE 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 18.8490, -66.6785. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Barceloneta Municipio, PR 44 km (27 mi) SSE earthquakes near Barceloneta Municipio
Arecibo Municipio, PR 46 km (29 mi) S earthquakes near Arecibo Municipio
Hatillo Municipio, PR 47 km (29 mi) SSW earthquakes near Hatillo Municipio
Camuy Municipio, PR 49 km (30 mi) SSW earthquakes near Camuy Municipio
Manatí Municipio, PR 49 km (30 mi) SSE earthquakes near Manatí Municipio
Quebradillas Municipio, PR 50 km (31 mi) SSW earthquakes near Quebradillas Municipio

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

Aftershocks so far

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

  1. 3.1 59 km N of Tierras Nuevas Poniente, Puerto Rico
  2. 3.3 64 km N of Tierras Nuevas Poniente, Puerto Rico
  3. 3.0 68 km N of Tierras Nuevas Poniente, Puerto Rico
  4. 2.8 72 km N of Tierras Nuevas Poniente, Puerto Rico
  5. 3.1 66 km N of Tierras Nuevas Poniente, Puerto Rico
  6. 3.2 59 km N of Tierras Nuevas Poniente, Puerto Rico
  7. 3.0 67 km N of Tierras Nuevas Poniente, Puerto Rico
  8. 3.1 68 km N of Tierras Nuevas Poniente, Puerto Rico
  9. 3.1 74 km N of Tierras Nuevas Poniente, Puerto Rico
  10. 3.1 70 km N of Tierras Nuevas Poniente, Puerto Rico
  11. 2.7 72 km N of Tierras Nuevas Poniente, Puerto Rico
  12. 3.0 64 km N of Tierras Nuevas Poniente, Puerto Rico
  13. 2.8 48 km N of Tierras Nuevas Poniente, Puerto Rico
  14. 3.3 9 km N of Tierras Nuevas Poniente, Puerto Rico
  15. 3.1 47 km N of Brenas, 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.