QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Brenas, PR

No earthquake was likely felt in Brenas in the 24 hours to 10:40 am AST (14:40 UTC). The last one was M 4.8, 87 km (54 mi) SW, at 9:19 am AST on 18 September 2026, estimated intensity III (weak) in town; 86 felt reports to USGS. Every earthquake near Brenas

This page: a magnitude 2.9 earthquake was recorded 9 km (6 mi) north-northwest of Brenas, PR, at 11:21 pm AST on 27 March 2025 (03:21 UTC), 95 km deep.

USGS: 9 km NNW of Brenas, Puerto Rico

35 km (22 mi) WNW of San Juan, PR · 28 km (17 mi) NW of Bayamón, PR

11:21 pm AST, Mar 27, 2025 · · 95 km deep · released about 780 lb of TNT

10 km30 km60 km120 km N Vega Baja Municipio 11 kmVega Alta Municipio 13 kmDorado Municipio 13 kmManatí Municipio 18 kmToa Baja Municipio 20 kmBarceloneta Municipio 22 kmToa Alta Municipio 24 kmCataño Municipio 25 kmMorovis Municipio 26 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
11:21 pm AST on 27 March 2025 ()
Where
9 km (6 mi) north-northwest of Brenas, PR · earthquakes near Brenas
Magnitude
M 2.9 (md)
Depth
95 km below the surface
Felt
no reports yet
Nearest
Vega Baja Municipio, 11 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 593 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 Brenas, 9 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.

Earthquakes near other towns within 30 km: Sabana, Ceiba, Vega Baja, Monserrate, San Antonio, Dorado.

How big was it?

This earthquake released about 780 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 19,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 14,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.2× the energy of this one
  4. This earthquake M 2.9 about 780 lb of TNT

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 620 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 5.8 12 km N of Garrochales, Puerto Rico · 21 km W of this epicentre
  2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 40 km SE of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 6 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 18.5473, -66.3623. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Vega Baja Municipio, PR 11 km (7 mi) SSW earthquakes near Vega Baja Municipio
Vega Alta Municipio, PR 13 km (8 mi) SSE earthquakes near Vega Alta Municipio
Dorado Municipio, PR 13 km (8 mi) SE earthquakes near Dorado Municipio
Manatí Municipio, PR 18 km (11 mi) SW earthquakes near Manatí Municipio
Toa Baja Municipio, PR 20 km (13 mi) ESE earthquakes near Toa Baja Municipio
Barceloneta Municipio, PR 22 km (14 mi) WSW earthquakes near Barceloneta Municipio

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

Aftershocks so far

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

  1. 2.3 3 km WNW of Orocovis, Puerto Rico
  2. 3.5 9 km NNW of San Juan, Puerto Rico
  3. 2.6 3 km WNW of Orocovis, Puerto Rico
  4. 3.5 54 km N of Brenas, Puerto Rico
  5. 3.2 2 km ESE of Sabana Hoyos, Puerto Rico
  6. 2.9 2 km NNW of Carrizales, Puerto Rico
  7. 2.3 8 km E of Jayuya, Puerto Rico
  8. 2.7 22 km NNE of Carrizales, Puerto Rico
  9. 3.0 26 km N of Garrochales, Puerto Rico
  10. 3.2 8 km NE of Dorado, Puerto Rico
  11. 2.2 4 km WNW of Orocovis, Puerto Rico
  12. 2.6 4 km NW of Orocovis, Puerto Rico
  13. 2.6 6 km WSW of Guaynabo, Puerto Rico
  14. 3.0 3 km N of Palomas, Puerto Rico
  15. 3.0 7 km NNE of Dorado, 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.