QuakeIndex

Earthquake · reviewed by a seismologist

M 4.1ml

Earthquake near Guánica, PR

No earthquake was likely felt in Guánica in the 24 hours to 10:50 am AST (14:50 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 4.1 earthquake was recorded 15 km (10 mi) south-southeast of Guánica, PR, at 9:05 am AST on 11 January 2020 (13:05 UTC), 10 km deep. 294 people have reported feeling it to USGS.

USGS: 15 km SSE of Guánica, Puerto Rico

32 km (20 mi) SW of Ponce, PR

9:05 am AST, Jan 11, 2020 · · 10 km deep · released about 21 tons of TNT

Every earthquake near Guánica Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guánica Municipio 13 kmGuayanilla Municipio 21 kmLajas Municipio 23 kmPeñuelas Municipio 26 kmYauco Municipio 28 kmSabana Grande Municipio 29 kmPonce Municipio 34 kmSan Germán Municipio 35 kmCabo Rojo Municipio 37 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
9:05 am AST on 11 January 2020 ()
Where
15 km (10 mi) south-southeast of Guánica, PR · earthquakes near Guánica
Magnitude
M 4.1 (ml)
Depth
10 km below the surface
Felt
294 reports · strongest reported intensity VII
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Nearest
Guánica Municipio, 13 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2414 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 104 km (65 mi) from the epicentre. In Guánica, 15 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 22 km, intensity III · Yauco 22 km, intensity III · Magas Arriba 23 km, intensity III · Tallaboa 25 km, intensity III · Tallaboa Alta 30 km, intensity III · San Germán 33 km, intensity III · Ponce 33 km, intensity III · Pole Ojea 36 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 21 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 7,900× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 350× the energy of this one
  3. Magna, Utah 2020 M 5.7 250× the energy of this one
  4. This earthquake M 4.1 about 21 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 45× 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 2,800 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 17.8355, -66.8771. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guánica Municipio, PR 13 km (8 mi) NNW earthquakes near Guánica Municipio
Guayanilla Municipio, PR 21 km (13 mi) NNE earthquakes near Guayanilla Municipio
Lajas Municipio, PR 23 km (15 mi) NW earthquakes near Lajas Municipio
Peñuelas Municipio, PR 26 km (16 mi) NE earthquakes near Peñuelas 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. 2.6 25 km SSE of Maria Antonia, Puerto Rico
  2. 2.7 8 km SSE of Maria Antonia, Puerto Rico
  3. 3.3 8 km S of Indios, Puerto Rico
  4. 3.8 Puerto Rico region
  5. 3.0 7 km SSE of Maria Antonia, Puerto Rico
  6. 3.4 7 km S of Indios, Puerto Rico
  7. 2.9 6 km S of Indios, Puerto Rico
  8. 3.6 10 km S of Indios, Puerto Rico
  9. 2.7 1 km WSW of Guayanilla, Puerto Rico
  10. 3.2 12 km SSE of Maria Antonia, Puerto Rico
  11. 3.2 11 km SSE of Guánica, Puerto Rico
  12. 2.7 11 km SSE of Maria Antonia, Puerto Rico
  13. 3.8 7 km S of Indios, Puerto Rico
  14. 2.7 10 km S of Indios, Puerto Rico
  15. 3.9 3 km SSW 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.