QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2md

Earthquake near Maria Antonia, PR

No earthquake was likely felt in Maria Antonia in the 24 hours to 11:32 am AST (15:32 UTC). The last one was M 2.1, 11 km (7 mi) ENE, at 4:39 pm AST on 9 November 2026, estimated intensity II (weak) in town. Every earthquake near Maria Antonia

This page: a magnitude 3.2 earthquake was recorded 21 km (13 mi) south-southeast of Maria Antonia, PR, at 9:46 pm AST on 13 August 2021 (01:46 UTC), 4.0 km deep.

USGS: 20 km SSE of Maria Antonia, Puerto Rico

29 km (18 mi) SW of Ponce, PR

9:46 pm AST, Aug 13, 2021 · · 4.0 km deep · released about 2,000 lb of TNT

Every earthquake near Maria Antonia Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guánica Municipio 20 kmGuayanilla Municipio 22 kmPeñuelas Municipio 26 kmPonce Municipio 31 kmLajas Municipio 31 kmYauco Municipio 31 kmSabana Grande Municipio 34 kmJuana Díaz Municipio 40 kmSan Germán Municipio 41 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
9:46 pm AST on 13 August 2021 ()
Where
21 km (13 mi) south-southeast of Maria Antonia, PR · earthquakes near Maria Antonia
Magnitude
M 3.2 (md)
Depth
4.0 km below the surface
Felt
no reports yet
Nearest
Guánica Municipio, 20 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1916 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 47 km (29 mi) from the epicentre. In Maria Antonia, 21 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: Tallaboa 23 km, intensity II · Guayanilla 24 km, intensity II · Magas Arriba 24 km, intensity II · Yauco 26 km, intensity II · Tallaboa Alta 30 km, intensity II · Ponce 30 km, intensity II · San Germán 39 km, intensity II · Adjuntas 41 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 2,000 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 170,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,700× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,400× the energy of this one
  4. This earthquake M 3.2 about 2,000 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2.1× 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 61,000 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 17.8063, -66.8120. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guánica Municipio, PR 20 km (12 mi) NW earthquakes near Guánica Municipio
Guayanilla Municipio, PR 22 km (14 mi) N earthquakes near Guayanilla Municipio
Peñuelas Municipio, PR 26 km (16 mi) NNE earthquakes near Peñuelas Municipio
Ponce Municipio, PR 31 km (19 mi) NE earthquakes near Ponce Municipio
Lajas Municipio, PR 31 km (19 mi) NW earthquakes near Lajas Municipio
Yauco Municipio, PR 31 km (20 mi) N earthquakes near Yauco Municipio

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

Aftershocks so far

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

  1. 2.6 12 km SSE of Maria Antonia, Puerto Rico
  2. 2.8 5 km WSW of Fuig, Puerto Rico
  3. 3.0 5 km SSW of Tallaboa, Puerto Rico
  4. 2.9 11 km SW of Guánica, Puerto Rico
  5. 2.9 4 km WSW of Fuig, Puerto Rico
  6. 2.4 1 km SE of Yauco, Puerto Rico
  7. 2.7 11 km SSW of Guánica, Puerto Rico
  8. 2.5 3 km WSW of Guánica, Puerto Rico
  9. 2.8 4 km SSW of Guánica, Puerto Rico
  10. 2.7 1 km NNE of Indios, Puerto Rico
  11. 2.4 6 km WSW of La Parguera, Puerto Rico
  12. 3.1 5 km SW of Guánica, Puerto Rico
  13. 2.5 2 km WNW of Indios, Puerto Rico
  14. 2.6 2 km W of Guayanilla, Puerto Rico
  15. 2.3 7 km SE of Maria Antonia, 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.