QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Cayey, PR

No earthquake was likely felt in Cayey in the 24 hours to 5:50 pm AST (21:50 UTC). The last one was M 3.3, 38 km (24 mi) SW, at 8:40 am AST on 1 November 2026, estimated intensity II (weak) in town. Every earthquake near Cayey

This page: a magnitude 1.6 earthquake was recorded 3 km (2 mi) southeast of Cayey, PR, at 4:30 am AST on 3 November 2018 (08:30 UTC), 12 km deep.

USGS: 2 km SE of Cayey, Puerto Rico

36 km (22 mi) SSW of San Juan, PR · 19 km (12 mi) SW of Caguas, PR

4:30 am AST, Nov 3, 2018 · · 12 km deep · released about 7.8 lb of TNT

Every earthquake near Cayey Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Cayey Municipio 1 kmCidra Municipio 9 kmAibonito Municipio 13 kmGuayama Municipio 13 kmComerío Municipio 16 kmCaguas Municipio 17 kmArroyo Municipio 18 kmSalinas Municipio 18 kmAguas Buenas Municipio 18 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
4:30 am AST on 3 November 2018 ()
Where
3 km (2 mi) southeast of Cayey, PR · earthquakes near Cayey
Magnitude
M 1.6 (md)
Depth
12 km below the surface
Felt
no reports yet
Nearest
Cayey Municipio, 1 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2930 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 Cayey, 3 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: Parcelas Nuevas, G. L. Garcia, La Plena, Cidra, Parcelas La Milagrosa, Vázquez.

How big was it?

This earthquake released about 7.8 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 1,900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 120× the energy of this one
  4. This earthquake M 1.6 about 7.8 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 31,000 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 19 km N of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 50 km NNW 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 18.0936, -66.1486. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cayey Municipio, PR 1 km (1 mi) NNW earthquakes near Cayey Municipio
Cidra Municipio, PR 9 km (6 mi) N earthquakes near Cidra Municipio
Aibonito Municipio, PR 13 km (8 mi) WNW earthquakes near Aibonito Municipio
Guayama Municipio, PR 13 km (8 mi) S earthquakes near Guayama Municipio
Comerío Municipio, PR 16 km (10 mi) NNW earthquakes near Comerío Municipio
Caguas Municipio, PR 17 km (10 mi) NE earthquakes near Caguas Municipio

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

Aftershocks so far

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

  1. 2.8 4 km E of Bayamón, Puerto Rico
  2. 2.0 2 km E of Ponce, Puerto Rico
  3. 1.8 1 km NNW of Sumidero, Puerto Rico
  4. 1.7 7 km SSW of Capitanejo, Puerto Rico
  5. 1.9 2 km SW of Las Ollas, Puerto Rico
  6. 1.8 1 km NW of H. Rivera Colon, Puerto Rico
  7. 1.6 3 km SE of Santa Isabel, Puerto Rico
  8. 2.9 2 km ESE of H. Rivera Colon, Puerto Rico
  9. 2.3 4 km ESE of Ponce, Puerto Rico
  10. 2.0 Puerto Rico region
  11. 1.6 4 km SSW of Playita Cortada, Puerto Rico
  12. 1.9 3 km ESE of Ponce, Puerto Rico
  13. 1.7 8 km S of Emajagua, Puerto Rico
  14. 2.5 9 km SSW of Arroyo, Puerto Rico
  15. 2.6 2 km ENE of Corozal, 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.