QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Earthquake near Guánica, PR

No earthquake was likely felt in Guánica in the 24 hours to 10:48 am AST (14:48 UTC). The last one was M 2.1, 13 km (8 mi) ENE, at 4:39 pm AST on 9 November 2026, estimated intensity II (weak) in town. Every earthquake near Guánica

This page: a magnitude 3.1 earthquake was recorded 5 km (3 mi) south-southwest of Guánica, PR, at 10:35 pm AST on 8 April 2023 (02:35 UTC), 5.7 km deep. 1 person has reported feeling it to USGS.

USGS: 4 km SSW of Guánica, Puerto Rico

33 km (20 mi) WSW of Ponce, PR

10:35 pm AST, Apr 8, 2023 · · 5.7 km deep · released about 1,400 lb of TNT

Every earthquake near Guánica Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guánica Municipio 2 kmLajas Municipio 13 kmGuayanilla Municipio 16 kmSabana Grande Municipio 17 kmYauco Municipio 19 kmSan Germán Municipio 23 kmPeñuelas Municipio 23 kmMaricao Municipio 27 kmCabo Rojo Municipio 28 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
10:35 pm AST on 8 April 2023 ()
Where
5 km (3 mi) south-southwest of Guánica, PR · earthquakes near Guánica
Magnitude
M 3.1 (md)
Depth
5.7 km below the surface
Felt
1 report · strongest reported intensity IV
Nearest
Guánica Municipio, 2 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1312 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 42 km (26 mi) from the epicentre. In Guánica, 5 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: Yauco 14 km, intensity III · Guayanilla 17 km, intensity III · Magas Arriba 19 km, intensity II · San Germán 21 km, intensity II · Tallaboa 23 km, intensity II · Tallaboa Alta 27 km, intensity II · Pole Ojea 28 km, intensity II · Puerto Real 32 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,400 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 6.7 230,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 10,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,400× the energy of this one
  4. This earthquake M 3.1 about 1,400 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.5× 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 6.4 on 2020-01-07 — about 83,000 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 17.9297, -66.9252. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guánica Municipio, PR 2 km (1 mi) N earthquakes near Guánica Municipio
Lajas Municipio, PR 13 km (8 mi) WNW earthquakes near Lajas Municipio
Guayanilla Municipio, PR 16 km (10 mi) ENE earthquakes near Guayanilla Municipio
Sabana Grande Municipio, PR 17 km (11 mi) N earthquakes near Sabana Grande Municipio
Yauco Municipio, PR 19 km (12 mi) NNE earthquakes near Yauco Municipio
San Germán Municipio, PR 23 km (14 mi) NNW earthquakes near San Germán Municipio

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

Aftershocks so far

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

  1. 2.3 5 km WSW of Fuig, Puerto Rico
  2. 2.0 3 km SE of Palomas, Puerto Rico
  3. 2.7 6 km E of La Parguera, Puerto Rico
  4. 2.4 Mona Passage
  5. 2.6 5 km NW of Sabana Grande, Puerto Rico
  6. 1.9 1 km S of Sabana Grande, Puerto Rico
  7. 2.9 Puerto Rico region
  8. 2.5 5 km WSW of Guánica, Puerto Rico
  9. 2.4 5 km WSW of Guánica, Puerto Rico
  10. 2.2 6 km SW of Fuig, Puerto Rico
  11. 1.8 6 km WSW of Fuig, Puerto Rico
  12. 2.1 Puerto Rico region
  13. 1.9 4 km SSW of Liborio Negron Torres, Puerto Rico
  14. 2.3 Puerto Rico region
  15. 2.1 4 km SW of Guánica, 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.