QuakeIndex

Earthquake · reviewed by a seismologist

M 3.7ml

Earthquake near Guánica, PR

Yes: an earthquake was likely felt in Guánica in the last 24 hours. M 2.1, 7 km (4 mi) ENE of Guánica, at 4:14 pm AST on 11 November 2026 (20:14 UTC); the estimated shaking in Guánica was intensity II (weak). Every earthquake near Guánica

This page: a magnitude 3.7 earthquake was recorded 16 km (10 mi) south-southeast of Guánica, PR, at 3:43 am AST on 24 December 2020 (07:43 UTC), 10 km deep. 8 people have reported feeling it to USGS.

USGS: 16 km SSE of Guánica, Puerto Rico

30 km (18 mi) SW of Ponce, PR

3:43 am AST, Dec 24, 2020 · · 10 km deep · released about 5.4 tons of TNT

Every earthquake near Guánica Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guánica Municipio 15 kmGuayanilla Municipio 19 kmPeñuelas Municipio 24 kmLajas Municipio 26 kmYauco Municipio 28 kmSabana Grande Municipio 29 kmPonce Municipio 31 kmSan Germán Municipio 36 kmMaricao 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
3:43 am AST on 24 December 2020 ()
Where
16 km (10 mi) south-southeast of Guánica, PR · earthquakes near Guánica
Magnitude
M 3.7 (ml)
Depth
10 km below the surface
Felt
8 reports · strongest reported intensity III
Measured shaking
intensity II (ShakeMap)
Nearest
Guánica Municipio, 15 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2076 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 75 km (47 mi) from the epicentre. In Guánica, 16 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: Guayanilla 21 km, intensity III · Magas Arriba 22 km, intensity III · Yauco 22 km, intensity III · Tallaboa 22 km, intensity III · Tallaboa Alta 28 km, intensity III · Ponce 30 km, intensity III · San Germán 34 km, intensity II · Adjuntas 38 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 5.4 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.7 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 32,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,000× the energy of this one
  4. This earthquake M 3.7 about 5.4 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 11× 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 11,000 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 17.8377, -66.8460. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guánica Municipio, PR 15 km (9 mi) NNW earthquakes near Guánica Municipio
Guayanilla Municipio, PR 19 km (12 mi) NNE earthquakes near Guayanilla Municipio
Peñuelas Municipio, PR 24 km (15 mi) NNE earthquakes near Peñuelas Municipio
Lajas Municipio, PR 26 km (16 mi) NW earthquakes near Lajas Municipio
Yauco Municipio, PR 28 km (17 mi) N earthquakes near Yauco Municipio
Sabana Grande Municipio, PR 29 km (18 mi) NNW earthquakes near Sabana Grande 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. 1.8 6 km SE of Maria Antonia, Puerto Rico
  2. 2.5 5 km SE of Maria Antonia, Puerto Rico
  3. 1.6 2 km E of Palomas, Puerto Rico
  4. 2.0 5 km SSW of Indios, Puerto Rico
  5. 2.4 7 km SE of Maria Antonia, Puerto Rico
  6. 4.1 6 km SE of Maria Antonia, Puerto Rico
  7. 2.6 6 km SE of Maria Antonia, Puerto Rico
  8. 2.0 5 km SE of Maria Antonia, Puerto Rico
  9. 2.3 9 km SSE of Maria Antonia, Puerto Rico
  10. 4.7 Puerto Rico region
  11. 3.1 6 km SE of Maria Antonia, Puerto Rico
  12. 3.7 5 km SSW of Indios, Puerto Rico
  13. 2.2 7 km SE of Maria Antonia, Puerto Rico
  14. 2.6 6 km SE of Maria Antonia, Puerto Rico
  15. 2.9 8 km S of Indios, 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.