QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Earthquake near Cayey, PR

No earthquake was likely felt in Cayey in the 24 hours to 7:36 am AST (11:36 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 3.1 earthquake was recorded 2 km (1 mi) southeast of Cayey, PR, at 6:07 am AST on 28 May 2023 (10:07 UTC), 15 km deep. 1 person has reported feeling it to USGS.

USGS: 2 km SE of Cayey, Puerto Rico

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

6:07 am AST, May 28, 2023 · · 15 km deep · released about 1,200 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 8 kmAibonito Municipio 13 kmGuayama Municipio 14 kmComerío Municipio 16 kmCaguas Municipio 16 kmAguas Buenas Municipio 18 kmArroyo Municipio 18 kmSalinas Municipio 19 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
6:07 am AST on 28 May 2023 ()
Where
2 km (1 mi) southeast of Cayey, PR · earthquakes near Cayey
Magnitude
M 3.1 (md)
Depth
15 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Cayey Municipio, 1 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1265 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, people at rest would likely notice it out to about 37 km (23 mi) from the epicentre. In Cayey, 2 km away, the estimate is intensity III (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.

Likely felt in: Cayey 2 km, intensity III · Guayama 13 km, intensity II · Sumidero 13 km, intensity II · Jagual 18 km, intensity II · Caguas 18 km, intensity II · Coamo 22 km, intensity II · Guaynabo 29 km, intensity II · Emajagua 30 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,200 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 280,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 12,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 8,800× the energy of this one
  4. This earthquake M 3.1 about 1,200 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.3× 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.6 on 2016-12-05 — about 200 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 · 18 km N of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 49 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 18.0997, -66.1480. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cayey Municipio, PR 1 km (0 mi) NW earthquakes near Cayey Municipio
Cidra Municipio, PR 8 km (5 mi) N earthquakes near Cidra Municipio
Aibonito Municipio, PR 13 km (8 mi) WNW earthquakes near Aibonito Municipio
Guayama Municipio, PR 14 km (9 mi) S earthquakes near Guayama Municipio
Comerío Municipio, PR 16 km (10 mi) NNW earthquakes near Comerío Municipio
Caguas Municipio, PR 16 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

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

  1. 2.7 16 km S of Central Aguirre, Puerto Rico
  2. 3.0 16 km S of Central Aguirre, Puerto Rico
  3. 2.5 16 km SE of El Negro, Puerto Rico
  4. 2.3 6 km S of Punta Santiago, Puerto Rico
  5. 2.9 1 km WSW of Coquí, Puerto Rico
  6. 1.9 8 km ENE of Villalba, Puerto Rico
  7. 2.1 Puerto Rico region
  8. 2.6 Puerto Rico region
  9. 2.6 2 km WNW of Bayamon, Puerto Rico
  10. 2.9 2 km NNE of Parcelas La Milagrosa, Puerto Rico
  11. 2.7 1 km W of Juncos, Puerto Rico
  12. 3.0 Puerto Rico region
  13. 3.0 Puerto Rico region
  14. 3.2 6 km N of San Juan, Puerto Rico
  15. 3.0 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.