QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Central Aguirre, PR

No earthquake was likely felt in Central Aguirre in the 24 hours to 5:20 pm AST (21:20 UTC). The last one was M 3.0, 23 km (14 mi) WSW, at 7:09 pm AST on 5 November 2026, estimated intensity II (weak) in town. Every earthquake near Central Aguirre

This page: a magnitude 1.6 earthquake was recorded 4 km (3 mi) west of Central Aguirre, PR, at 8:20 pm AST on 3 October 2018 (00:20 UTC), 13 km deep.

USGS: 4 km W of Central Aguirre, Puerto Rico

55 km (34 mi) SSW of San Juan, PR · 39 km (24 mi) E of Ponce, PR

8:20 pm AST, Oct 3, 2018 · · 13 km deep · released about 9 lb of TNT

Every earthquake near Central Aguirre Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Salinas Municipio 3 kmGuayama Municipio 13 kmSanta Isabel Municipio 13 kmCoamo Municipio 20 kmAibonito Municipio 20 kmCayey Municipio 21 kmArroyo Municipio 23 kmJuana Díaz Municipio 25 kmCidra 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
8:20 pm AST on 3 October 2018 ()
Where
4 km (3 mi) west of Central Aguirre, PR · earthquakes near Central Aguirre
Magnitude
M 1.6 (md)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Salinas Municipio, 3 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2961 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 Central Aguirre, 4 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: Coquí, Salinas, Coco, Las Ochenta, Jobos, Parcelas Peñuelas.

How big was it?

This earthquake released about 9 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 9 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 4.6 on 2016-12-05 — about 27,000 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 37 km NNE 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 17.9468, -66.2608. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Salinas Municipio, PR 3 km (2 mi) N earthquakes near Salinas Municipio
Guayama Municipio, PR 13 km (8 mi) ENE earthquakes near Guayama Municipio
Santa Isabel Municipio, PR 13 km (8 mi) W earthquakes near Santa Isabel Municipio
Coamo Municipio, PR 20 km (13 mi) NNW earthquakes near Coamo Municipio
Aibonito Municipio, PR 20 km (13 mi) N earthquakes near Aibonito Municipio
Cayey Municipio, PR 21 km (13 mi) NNE earthquakes near Cayey 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. 1.7 Puerto Rico region
  2. 2.0 5 km S of Salinas, Puerto Rico
  3. 2.5 4 km SW of Patillas, Puerto Rico
  4. 1.9 11 km S of Emajagua, Puerto Rico
  5. 2.6 Puerto Rico region
  6. 2.0 7 km SE of Arroyo, Puerto Rico
  7. 2.1 4 km ESE of Palmarejo, Puerto Rico
  8. 2.0 Puerto Rico region
  9. 2.0 3 km SSW of Jauca, Puerto Rico
  10. 2.3 2 km SSW of Jauca, Puerto Rico
  11. 2.0 2 km SSW of Jauca, Puerto Rico
  12. 2.0 2 km SE of Santa Isabel, Puerto Rico
  13. 2.1 1 km SSE of G. L. Garcia, Puerto Rico
  14. 1.6 3 km NNW of Playita Cortada, Puerto Rico
  15. 2.5 11 km S of Emajagua, 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.