QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

Earthquake near Brenas, PR

No earthquake was likely felt in Brenas in the 24 hours to 4:17 pm AST (20:17 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 2.4 earthquake was recorded 19 km (12 mi) north-northwest of Brenas, PR, at 7:38 am AST on 7 September 2018 (11:38 UTC), 60 km deep.

USGS: 18 km NNW of Brenas, Puerto Rico

43 km (27 mi) NW of San Juan, PR · 37 km (23 mi) NW of Bayamón, PR

7:38 am AST, Sep 7, 2018 · · 60 km deep · released about 130 lb of TNT

Every earthquake near Brenas Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Vega Baja Municipio 19 kmVega Alta Municipio 22 kmDorado Municipio 22 kmManatí Municipio 23 kmBarceloneta Municipio 24 kmToa Baja Municipio 29 kmCataño Municipio 33 kmToa Alta Municipio 34 kmFlorida Municipio 34 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
7:38 am AST on 7 September 2018 ()
Where
19 km (12 mi) north-northwest of Brenas, PR · earthquakes near Brenas
Magnitude
M 2.4 (md)
Depth
60 km below the surface
Felt
no reports yet
Nearest
Vega Baja Municipio, 19 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2987 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Brenas, 19 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, Vega Baja, Tierras Nuevas Poniente, Ceiba, Monserrate, Coto Norte.

How big was it?

This earthquake released about 130 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 120,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 83,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.4× the energy of this one
  4. This earthquake M 2.4 about 130 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 3,700 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 5.8 12 km N of Garrochales, Puerto Rico · 19 km WSW of this epicentre
  2. 5.5 64 km N of Tierras Nuevas Poniente, Puerto Rico · 47 km N of this epicentre
  3. 5.1 66 km N of Brenas, Puerto Rico · 49 km N of this epicentre
  4. 5.1 3 km W of Aguas Buenas, Puerto Rico · 49 km SE of this epicentre
  5. 5.0 3 km N of Brenas, Puerto Rico · 15 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 18.6275, -66.3998. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Vega Baja Municipio, PR 19 km (12 mi) S earthquakes near Vega Baja Municipio
Vega Alta Municipio, PR 22 km (14 mi) SSE earthquakes near Vega Alta Municipio
Dorado Municipio, PR 22 km (14 mi) SE earthquakes near Dorado Municipio
Manatí Municipio, PR 23 km (14 mi) SSW earthquakes near Manatí Municipio
Barceloneta Municipio, PR 24 km (15 mi) SW earthquakes near Barceloneta Municipio
Toa Baja Municipio, PR 29 km (18 mi) SE earthquakes near Toa Baja Municipio

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

Aftershocks so far

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

  1. 2.6 52 km N of Carrizales, Puerto Rico
  2. 2.7 50 km N of Carrizales, Puerto Rico
  3. 2.3 3 km SSW of Vega Alta, Puerto Rico
  4. 2.0 2 km SW of Corozal, Puerto Rico
  5. 2.8 40 km N of Brenas, Puerto Rico
  6. 2.8 Puerto Rico region
  7. 1.7 7 km SE of Pájaros, Puerto Rico
  8. 2.6 Puerto Rico region
  9. 2.5 Puerto Rico region
  10. 2.8 Puerto Rico region
  11. 2.9 61 km N of Tierras Nuevas Poniente, Puerto Rico
  12. 2.5 55 km N of Tierras Nuevas Poniente, Puerto Rico
  13. 2.8 61 km N of Tierras Nuevas Poniente, Puerto Rico
  14. 2.4 26 km N of San Juan, Puerto Rico
  15. 2.3 9 km NNE of Carrizales, 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.