QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Guayama, PR

No earthquake was likely felt in Guayama in the 24 hours to 3:33 pm AST (19:33 UTC). The last one was M 3.3, 35 km (22 mi) WSW, at 8:40 am AST on 1 November 2026, estimated intensity II (weak) in town. Every earthquake near Guayama

This page: a magnitude 1.9 earthquake was recorded 9 km (6 mi) south-southwest of Guayama, PR, at 6:06 am AST on 27 October 2023 (10:06 UTC), 14 km deep.

USGS: Puerto Rico region

56 km (35 mi) S of San Juan, PR · 38 km (23 mi) SSW of Caguas, PR

6:06 am AST, Oct 27, 2023 · · 14 km deep · released about 19 lb of TNT

Every earthquake near Guayama Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guayama Municipio 7 kmArroyo Municipio 13 kmSalinas Municipio 14 kmPatillas Municipio 20 kmCayey Municipio 21 kmSanta Isabel Municipio 25 kmAibonito Municipio 27 kmMaunabo Municipio 29 kmCidra Municipio 29 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
6:06 am AST on 27 October 2023 ()
Where
9 km (6 mi) south-southwest of Guayama, PR · earthquakes near Guayama
Magnitude
M 1.9 (md)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Guayama Municipio, 7 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1111 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 5 km (3 mi) from the epicentre. In Guayama, 9 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: Jobos, Central Aguirre, Coquí, Olimpo, Arroyo, Corazón.

How big was it?

This earthquake released about 19 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 790,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 560,000× the energy of this one
  3. Around the size people start to feel M 3.0 50× the energy of this one
  4. This earthquake M 1.9 about 19 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 in our catalogue was M 4.6 on 2016-12-05 — about 12,000 times the energy of this one.

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 17.9103, -66.1517. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guayama Municipio, PR 7 km (4 mi) NNE earthquakes near Guayama Municipio
Arroyo Municipio, PR 13 km (8 mi) ENE earthquakes near Arroyo Municipio
Salinas Municipio, PR 14 km (8 mi) WNW earthquakes near Salinas Municipio
Patillas Municipio, PR 20 km (13 mi) ENE earthquakes near Patillas Municipio
Cayey Municipio, PR 21 km (13 mi) N earthquakes near Cayey Municipio
Santa Isabel Municipio, PR 25 km (16 mi) W earthquakes near Santa Isabel Municipio

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

Aftershocks so far

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

  1. 2.7 6 km SSE of Salinas, Puerto Rico
  2. 2.4 2 km S of Salinas, Puerto Rico
  3. 2.9 5 km SSE of Salinas, Puerto Rico
  4. 2.2 3 km WSW of Central Aguirre, Puerto Rico
  5. 2.3 5 km SSE of Salinas, Puerto Rico
  6. 2.1 3 km SSE of Salinas, Puerto Rico
  7. 2.8 5 km NW of Orocovis, Puerto Rico
  8. 2.7 3 km NW of Orocovis, Puerto Rico
  9. 2.1 4 km ENE of Bayamon, Puerto Rico
  10. 2.2 5 km SSW of Arroyo, Puerto Rico
  11. 2.4 4 km ENE of Bayamon, Puerto Rico
  12. 2.5 7 km ESE of Naranjito, Puerto Rico
  13. 2.2 5 km SSE of Salinas, Puerto Rico
  14. 2.4 6 km SSE of Salinas, Puerto Rico
  15. 2.6 6 km SSE of Salinas, 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.