QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3md

Earthquake near Guánica, PR

No earthquake was likely felt in Guánica in the 24 hours to 11:29 am AST (15:29 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 3.3 earthquake was recorded 7 km (4 mi) southwest of Guánica, PR, at 4:32 am AST on 10 July 2020 (08:32 UTC), 7.0 km deep.

USGS: 6 km SW of Guánica, Puerto Rico

35 km (22 mi) WSW of Ponce, PR

4:32 am AST, Jul 10, 2020 · · 7.0 km deep · released about 1.4 tons of TNT

Every earthquake near Guánica Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guánica Municipio 4 kmLajas Municipio 11 kmSabana Grande Municipio 18 kmGuayanilla Municipio 18 kmYauco Municipio 20 kmSan Germán Municipio 22 kmCabo Rojo Municipio 26 kmPeñuelas Municipio 26 kmMaricao 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
4:32 am AST on 10 July 2020 ()
Where
7 km (4 mi) southwest of Guánica, PR · earthquakes near Guánica
Magnitude
M 3.3 (md)
Depth
7.0 km below the surface
Felt
no reports yet
Measured shaking
intensity III (ShakeMap)
Nearest
Guánica Municipio, 4 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2244 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 53 km (33 mi) from the epicentre. In Guánica, 7 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 16 km, intensity III · Guayanilla 20 km, intensity III · San Germán 20 km, intensity III · Magas Arriba 22 km, intensity III · Pole Ojea 26 km, intensity II · Tallaboa 26 km, intensity II · Tallaboa Alta 30 km, intensity II · Puerto Real 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 1.4 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 120,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 5,200× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,700× the energy of this one
  4. This earthquake M 3.3 about 1.4 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 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 6.4 on 2020-01-07 — about 42,000 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 17.9250, -66.9496. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guánica Municipio, PR 4 km (2 mi) NE earthquakes near Guánica Municipio
Lajas Municipio, PR 11 km (7 mi) WNW earthquakes near Lajas Municipio
Sabana Grande Municipio, PR 18 km (11 mi) N earthquakes near Sabana Grande Municipio
Guayanilla Municipio, PR 18 km (11 mi) ENE earthquakes near Guayanilla Municipio
Yauco Municipio, PR 20 km (13 mi) NNE earthquakes near Yauco Municipio
San Germán Municipio, PR 22 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

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

  1. 3.3 2 km S of Guánica, Puerto Rico
  2. 2.7 4 km SSW of Guánica, Puerto Rico
  3. 2.5 5 km S of Guánica, Puerto Rico
  4. 2.5 Puerto Rico region
  5. 2.5 1 km SSE of Guánica, Puerto Rico
  6. 2.2 6 km SW of Guánica, Puerto Rico
  7. 2.1 4 km S of Guánica, Puerto Rico
  8. 2.4 4 km SSW of Guánica, Puerto Rico
  9. 2.4 1 km SW of Indios, Puerto Rico
  10. 2.7 3 km SW of Guánica, Puerto Rico
  11. 2.3 12 km SSE of Maria Antonia, Puerto Rico
  12. 3.0 5 km ESE of La Parguera, Puerto Rico
  13. 3.1 5 km SSE of Magas Arriba, Puerto Rico
  14. 2.7 4 km S of Guánica, Puerto Rico
  15. 2.5 5 km SE of La Parguera, 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.