QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

Earthquake near Potala Pastillo, PR

No earthquake was likely felt in Potala Pastillo in the 24 hours to 6:14 pm AST (22:14 UTC). The last one was M 2.2, 6 km (4 mi) NW, at 10:09 am AST on 7 November 2026, estimated intensity II (weak) in town. Every earthquake near Potala Pastillo

This page: a magnitude 2.8 earthquake was recorded 12 km (7 mi) southwest of Potala Pastillo, PR, at 12:00 am AST on 20 January 2021 (04:00 UTC), 4.0 km deep. 1 person has reported feeling it to USGS.

USGS: 11 km SW of Potala Pastillo, Puerto Rico

11 km (7 mi) SSE of Ponce, PR

12:00 am AST, Jan 20, 2021 · · 4.0 km deep · released about 400 lb of TNT

Every earthquake near Potala Pastillo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Ponce Municipio 10 kmJuana Díaz Municipio 13 kmSanta Isabel Municipio 20 kmPeñuelas Municipio 21 kmGuayanilla Municipio 26 kmVillalba Municipio 26 kmCoamo Municipio 31 kmJayuya Municipio 33 kmSalinas Municipio 33 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
12:00 am AST on 20 January 2021 ()
Where
12 km (7 mi) southwest of Potala Pastillo, PR · earthquakes near Potala Pastillo
Magnitude
M 2.8 (md)
Depth
4.0 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Ponce Municipio, 10 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1556 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 25 km (16 mi) from the epicentre. In Potala Pastillo, 12 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: Ponce 12 km, intensity III · Tallaboa 18 km, intensity II · Río Cañas Abajo 18 km, intensity II · Santa Isabel 19 km, intensity II · Tallaboa Alta 20 km, intensity II · Magas Arriba 24 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 400 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 38,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 27,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.4× the energy of this one
  4. This earthquake M 2.8 about 400 lb of TNT

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 300,000 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 17.9136, -66.5728. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Ponce Municipio, PR 10 km (6 mi) NNW earthquakes near Ponce Municipio
Juana Díaz Municipio, PR 13 km (8 mi) NE earthquakes near Juana Díaz Municipio
Santa Isabel Municipio, PR 20 km (12 mi) ENE earthquakes near Santa Isabel Municipio
Peñuelas Municipio, PR 21 km (13 mi) NW earthquakes near Peñuelas Municipio
Guayanilla Municipio, PR 26 km (16 mi) WNW earthquakes near Guayanilla Municipio
Villalba Municipio, PR 26 km (16 mi) NNE earthquakes near Villalba Municipio

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

Aftershocks so far

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

  1. 1.5 2 km SSE of Guánica, Puerto Rico
  2. 1.6 5 km WSW of Fuig, Puerto Rico
  3. 2.4 3 km SSW of Indios, Puerto Rico
  4. 1.8 5 km SSE of Guánica, Puerto Rico
  5. 1.9 6 km SSE of Maria Antonia, Puerto Rico
  6. 1.9 6 km SSE of Maria Antonia, Puerto Rico
  7. 1.6 5 km NNE of La Parguera, Puerto Rico
  8. 1.6 2 km WSW of Guánica, Puerto Rico
  9. 1.9 7 km SSE of Maria Antonia, Puerto Rico
  10. 1.9 3 km SW of Fuig, Puerto Rico
  11. 2.3 1 km ENE of Guayanilla, Puerto Rico
  12. 2.5 2 km W of Guayanilla, Puerto Rico
  13. 2.4 4 km ESE of Maria Antonia, Puerto Rico
  14. 2.0 1 km SSE of Maria Antonia, Puerto Rico
  15. 2.1 3 km SSW 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.