QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

Earthquake near Guayama, PR

No earthquake was likely felt in Guayama in the 24 hours to 4:31 pm AST (20:31 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 2.5 earthquake was recorded 20 km (13 mi) south-southeast of Guayama, PR, at 9:22 pm AST on 4 September 2023 (01:22 UTC), 22 km deep.

USGS: Puerto Rico region

66 km (41 mi) S of San Juan, PR · 47 km (29 mi) S of Caguas, PR

9:22 pm AST, Sep 4, 2023 · · 22 km deep · released about 180 lb of TNT

Every earthquake near Guayama Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Arroyo Municipio 18 kmGuayama Municipio 20 kmPatillas Municipio 23 kmMaunabo Municipio 27 kmSalinas Municipio 28 kmCayey Municipio 34 kmYabucoa Municipio 35 kmSanta Isabel Municipio 38 kmSan Lorenzo Municipio 39 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
9:22 pm AST on 4 September 2023 ()
Where
20 km (13 mi) south-southeast of Guayama, PR · earthquakes near Guayama
Magnitude
M 2.5 (md)
Depth
22 km below the surface
Felt
no reports yet
Nearest
Arroyo Municipio, 18 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1164 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 2 km (1 mi) from the epicentre. In Guayama, 20 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: Arroyo, Jobos, Palmas, Lamboglia, Corazón, Buena Vista.

How big was it?

This earthquake released about 180 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 86,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 61,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.4× the energy of this one
  4. This earthquake M 2.5 about 180 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 1,400 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 17.8090, -66.0570. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Arroyo Municipio, PR 18 km (11 mi) N earthquakes near Arroyo Municipio
Guayama Municipio, PR 20 km (13 mi) NNW earthquakes near Guayama Municipio
Patillas Municipio, PR 23 km (14 mi) NNE earthquakes near Patillas Municipio
Maunabo Municipio, PR 27 km (17 mi) NE earthquakes near Maunabo Municipio
Salinas Municipio, PR 28 km (18 mi) NW earthquakes near Salinas Municipio
Cayey Municipio, PR 34 km (21 mi) NNW earthquakes near Cayey Municipio

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

Aftershocks so far

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

  1. 3.5 3 km S of Salinas, Puerto Rico
  2. 2.5 17 km S of Central Aguirre, Puerto Rico
  3. 2.1 5 km SSE of Salinas, Puerto Rico
  4. 2.5 10 km S of Emajagua, Puerto Rico
  5. 2.1 4 km SSE of Salinas, Puerto Rico
  6. 2.5 5 km SW of Central Aguirre, Puerto Rico
  7. 3.2 36 km SE of Emajagua, Puerto Rico
  8. 2.5 2 km SSE of Caguas, Puerto Rico
  9. 2.3 6 km SSE of Salinas, Puerto Rico
  10. 2.0 Puerto Rico region
  11. 2.7 Puerto Rico region
  12. 3.3 4 km SSE of Salinas, Puerto Rico
  13. 3.2 Puerto Rico region
  14. 2.0 4 km SE of Salinas, Puerto Rico
  15. 2.1 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.