QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2md

Earthquake near Arecibo, PR

No earthquake was likely felt in Arecibo in the 24 hours to 1:37 pm AST (17:37 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 3.2 earthquake was recorded 7 km (5 mi) west-northwest of Arecibo, PR, at 11:43 pm AST on 26 July 2018 (03:43 UTC), 118 km deep. 1 person has reported feeling it to USGS.

USGS: Puerto Rico region

7 km (4 mi) NW of Arecibo, PR · 76 km (47 mi) W of San Juan, PR

11:43 pm AST, Jul 26, 2018 · · 118 km deep · released about 2,000 lb of TNT

Every earthquake near Arecibo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Hatillo Municipio 7 kmCamuy Municipio 11 kmArecibo Municipio 13 kmQuebradillas Municipio 16 kmBarceloneta Municipio 24 kmIsabela Municipio 25 kmLares Municipio 27 kmUtuado Municipio 27 kmFlorida Municipio 27 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
11:43 pm AST on 26 July 2018 ()
Where
7 km (5 mi) west-northwest of Arecibo, PR · earthquakes near Arecibo
Magnitude
M 3.2 (md)
Depth
118 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Hatillo Municipio, 7 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2955 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, 7 km away, the estimate is intensity I (not felt). 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: Carrizales, Corcovado, Hatillo, Camuy, Rafael Gonzalez, Rafael Capo.

How big was it?

This earthquake released about 2,000 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 170,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,700× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,400× the energy of this one
  4. This earthquake M 3.2 about 2,000 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2.1× 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.

Where

Epicentre 18.5023, -66.7788. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Hatillo Municipio, PR 7 km (4 mi) SSW earthquakes near Hatillo Municipio
Camuy Municipio, PR 11 km (7 mi) SW earthquakes near Camuy Municipio
Arecibo Municipio, PR 13 km (8 mi) SE earthquakes near Arecibo Municipio
Quebradillas Municipio, PR 16 km (10 mi) WSW earthquakes near Quebradillas Municipio
Barceloneta Municipio, PR 24 km (15 mi) E earthquakes near Barceloneta Municipio
Isabela Municipio, PR 25 km (15 mi) W earthquakes near Isabela Municipio

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

Aftershocks so far

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

  1. 1.7 8 km S of Villalba, Puerto Rico
  2. 1.7 2 km NNE of Santo Domingo, Puerto Rico
  3. 2.7 4 km ESE of Florida, Puerto Rico
  4. 2.2 11 km N of Arecibo, Puerto Rico
  5. 2.5 3 km NW of Las Marias, Puerto Rico
  6. 2.1 4 km SSW of San Sebastián, Puerto Rico
  7. 1.6 4 km SSW of Adjuntas, Puerto Rico
  8. 2.1 3 km N of Santo Domingo, Puerto Rico
  9. 1.7 4 km ESE of Maricao, Puerto Rico
  10. 2.5 19 km N of Arecibo, Puerto Rico
  11. 2.2 1 km SSE of Adjuntas, Puerto Rico
  12. 1.6 3 km SW of Adjuntas, Puerto Rico
  13. 1.7 6 km SSE of Adjuntas, Puerto Rico
  14. 2.9 43 km N of Isabela, Puerto Rico
  15. 2.2 9 km NNE of San Antonio, 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.