QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8Md

Earthquake near Cayey, PR

No earthquake was likely felt in Cayey in the 24 hours to 10:22 pm AST (02:22 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 1.8 earthquake was recorded 4 km (2 mi) south of Cayey, PR, at 5:35 am AST on 22 March 2017 (09:35 UTC), 17 km deep.

USGS: 3 km S of Cayey, Puerto Rico

38 km (23 mi) SSW of San Juan, PR · 21 km (13 mi) SW of Caguas, PR

5:35 am AST, Mar 22, 2017 · · 17 km deep · released about 15 lb of TNT

Every earthquake near Cayey Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Cayey Municipio 3 kmCidra Municipio 11 kmGuayama Municipio 12 kmAibonito Municipio 12 kmSalinas Municipio 16 kmComerío Municipio 17 kmArroyo Municipio 17 kmCaguas Municipio 19 kmAguas Buenas Municipio 20 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
5:35 am AST on 22 March 2017 ()
Where
4 km (2 mi) south of Cayey, PR · earthquakes near Cayey
Magnitude
M 1.8 (Md)
Depth
17 km below the surface
Felt
no reports yet
Nearest
Cayey Municipio, 3 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3523 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, 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: La Plena, Parcelas Nuevas, G. L. Garcia, Vázquez, Olimpo, Parcelas La Milagrosa.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 16,000 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 · 20 km N 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 18.0792, -66.1617. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cayey Municipio, PR 3 km (2 mi) NNE earthquakes near Cayey Municipio
Cidra Municipio, PR 11 km (7 mi) N earthquakes near Cidra Municipio
Guayama Municipio, PR 12 km (7 mi) SSE earthquakes near Guayama Municipio
Aibonito Municipio, PR 12 km (8 mi) WNW earthquakes near Aibonito Municipio
Salinas Municipio, PR 16 km (10 mi) SW earthquakes near Salinas Municipio
Comerío Municipio, PR 17 km (11 mi) NNW earthquakes near Comerío Municipio

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

Aftershocks so far

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

  1. 2.4 4 km W of Central Aguirre, Puerto Rico
  2. 2.0 1 km WSW of Potala Pastillo, Puerto Rico
  3. 1.9 10 km S of Emajagua, Puerto Rico
  4. 2.7 3 km SE of Pájaros, Puerto Rico
  5. 1.8 4 km SE of G. L. Garcia, Puerto Rico
  6. 2.3 12 km S of Potala Pastillo, Puerto Rico
  7. 2.8 16 km SSE of Jauca, Puerto Rico
  8. 2.1 1 km ESE of Playita, Puerto Rico
  9. 1.8 3 km NNW of Potala Pastillo, Puerto Rico
  10. 2.9 8 km ENE of San Juan, Puerto Rico
  11. 3.1 1 km SE of Ceiba, Puerto Rico
  12. 2.4 3 km S of Playita Cortada, Puerto Rico
  13. 1.7 3 km WNW of Candelero Arriba, Puerto Rico
  14. 2.2 11 km S of Emajagua, Puerto Rico
  15. 1.9 0 km NNE of Ponce, 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.