QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0md

Earthquake near Arecibo, PR

No earthquake was likely felt in Arecibo in the 24 hours to 11:29 am AST (15:29 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 3.0 earthquake was recorded 19 km (12 mi) north-northeast of Arecibo, PR, at 4:32 am AST on 29 July 2023 (08:32 UTC), 76 km deep.

USGS: 18 km NNE of Arecibo, Puerto Rico

63 km (39 mi) WNW of San Juan, PR · 22 km (13 mi) NE of Arecibo, PR

4:32 am AST, Jul 29, 2023 · · 76 km deep · released about 1,100 lb of TNT

Every earthquake near Arecibo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Barceloneta Municipio 17 kmArecibo Municipio 21 kmManatí Municipio 23 kmHatillo Municipio 27 kmFlorida Municipio 28 kmVega Baja Municipio 29 kmCamuy Municipio 32 kmVega Alta Municipio 36 kmQuebradillas Municipio 36 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
4:32 am AST on 29 July 2023 ()
Where
19 km (12 mi) north-northeast of Arecibo, PR · earthquakes near Arecibo
Magnitude
M 3.0 (md)
Depth
76 km below the surface
Felt
no reports yet
Nearest
Barceloneta Municipio, 17 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1028 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 Arecibo, 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: Garrochales, Animas, Sabana Hoyos, Barceloneta, Imbery, La Luisa.

How big was it?

This earthquake released about 1,100 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 300,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 13,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,400× the energy of this one
  4. This earthquake M 3.0 about 1,100 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 420 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 · 8 km SE of this epicentre
  2. 5.5 64 km N of Tierras Nuevas Poniente, Puerto Rico · 50 km NNE of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 32 km ESE 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 18.6152, -66.6203. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Barceloneta Municipio, PR 17 km (11 mi) SSE earthquakes near Barceloneta Municipio
Arecibo Municipio, PR 21 km (13 mi) SSW earthquakes near Arecibo Municipio
Manatí Municipio, PR 23 km (14 mi) SE earthquakes near Manatí Municipio
Hatillo Municipio, PR 27 km (17 mi) SW earthquakes near Hatillo Municipio
Florida Municipio, PR 28 km (17 mi) SSE earthquakes near Florida Municipio
Vega Baja Municipio, PR 29 km (18 mi) SE earthquakes near Vega Baja Municipio

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

Aftershocks so far

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

  1. 3.3 49 km N of Tierras Nuevas Poniente, Puerto Rico
  2. 2.6 4 km NNE of Carrizales, Puerto Rico
  3. 2.5 17 km NNW of Brenas, Puerto Rico
  4. 2.8 26 km NNE of Isabela, Puerto Rico
  5. 3.5 3 km WSW of Manatí, Puerto Rico
  6. 2.9 35 km N of Carrizales, Puerto Rico
  7. 2.8 20 km N of Carrizales, Puerto Rico
  8. 2.4 3 km W of Cayuco, Puerto Rico
  9. 2.6 16 km NNW of Camuy, Puerto Rico
  10. 3.2 Puerto Rico region
  11. 2.5 39 km N of Tierras Nuevas Poniente, Puerto Rico
  12. 2.5 3 km S of Quebrada, Puerto Rico
  13. 2.4 1 km N of Quebrada, Puerto Rico
  14. 2.7 11 km N of Arecibo, Puerto Rico
  15. 3.3 Puerto Rico region

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.