QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Puerto Real, PR

No earthquake was likely felt in Puerto Real in the 24 hours to 6:48 pm AST (22:48 UTC). The last one was M 2.1, 10 km (6 mi) SE, at 11:57 pm AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Puerto Real

This page: a magnitude 2.9 earthquake was recorded 16 km (10 mi) northwest of Puerto Real, PR, at 10:25 pm AST on 18 December 2020 (02:25 UTC), 17 km deep.

USGS: 15 km NW of Puerto Real, Puerto Rico

17 km (11 mi) WSW of Mayagüez, PR · 134 km (83 mi) WSW of San Juan, PR

10:25 pm AST, Dec 18, 2020 · · 17 km deep · released about 590 lb of TNT

Every earthquake near Puerto Real Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Hormigueros Municipio 20 kmRincón Municipio 20 kmCabo Rojo Municipio 23 kmAñasco Municipio 23 kmAguada Municipio 27 kmSan Germán Municipio 29 kmMoca Municipio 33 kmLajas Municipio 35 kmLas Marías Municipio 35 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
10:25 pm AST on 18 December 2020 ()
Where
16 km (10 mi) northwest of Puerto Real, PR · earthquakes near Puerto Real
Magnitude
M 2.9 (md)
Depth
17 km below the surface
Felt
no reports yet
Nearest
Hormigueros Municipio, 20 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2154 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 Puerto Real, 16 km away, the estimate is intensity II (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: Puerto Real 16 km, intensity II · Mayagüez 18 km, intensity II · Rincón 20 km, intensity II · Pole Ojea 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 590 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 26,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 18,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.6× the energy of this one
  4. This earthquake M 2.9 about 590 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 5.3 on 2020-07-03 — about 4,600 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.3 6 km WNW of Aguadilla, Puerto Rico · 32 km NNE of this epicentre
  2. 6.1 15 km WNW of San Antonio, Puerto Rico · 44 km N of this epicentre
  3. 5.8 4 km E of Moca, Puerto Rico · 36 km NE of this epicentre
  4. 5.2 19 km SW of Stella, Puerto Rico · 8 km WNW of this epicentre
  5. 5.1 21 km SW of Stella, Puerto Rico · 7 km W of this epicentre

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 18.1645, -67.3026. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Hormigueros Municipio, PR 20 km (12 mi) E earthquakes near Hormigueros Municipio
Rincón Municipio, PR 20 km (13 mi) NNE earthquakes near Rincón Municipio
Cabo Rojo Municipio, PR 23 km (14 mi) SE earthquakes near Cabo Rojo Municipio
Añasco Municipio, PR 23 km (14 mi) NE earthquakes near Añasco Municipio
Aguada Municipio, PR 27 km (16 mi) NNE earthquakes near Aguada Municipio
San Germán Municipio, PR 29 km (18 mi) ESE earthquakes near San Germán Municipio

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

Aftershocks so far

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

  1. 2.8 3 km NNE of La Parguera, Puerto Rico
  2. 1.9 8 km SW of La Parguera, Puerto Rico
  3. 3.0 6 km ESE of La Parguera, Puerto Rico
  4. 2.9 24 km W of Rincón, Puerto Rico
  5. 1.8 3 km SW of Fuig, Puerto Rico
  6. 2.1 7 km S of Guánica, Puerto Rico
  7. 2.1 3 km SSW of Guánica, Puerto Rico
  8. 2.3 6 km S of Guánica, Puerto Rico
  9. 2.2 4 km WSW of Guánica, Puerto Rico
  10. 2.2 2 km SSE of La Parguera, Puerto Rico
  11. 2.2 2 km SSE of Maria Antonia, Puerto Rico
  12. 3.5 4 km SW of Guánica, Puerto Rico
  13. 2.1 3 km WSW of Guánica, Puerto Rico
  14. 2.0 7 km WSW of Fuig, Puerto Rico
  15. 2.3 4 km NE 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.