QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Puerto Real, PR

No earthquake was likely felt in Puerto Real in the 24 hours to 12:55 pm AST (16:55 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 1.9 earthquake was recorded 5 km (3 mi) west-northwest of Puerto Real, PR, at 5:44 pm AST on 6 January 2021 (21:44 UTC), 18 km deep.

USGS: 5 km WNW of Puerto Real, Puerto Rico

16 km (10 mi) SW of Mayagüez, PR · 129 km (80 mi) WSW of San Juan, PR

5:44 pm AST, Jan 6, 2021 · · 18 km deep · released about 25 lb of TNT

10 km30 km60 km120 km N Cabo Rojo Municipio 11 kmHormigueros Municipio 14 kmSan Germán Municipio 21 kmLajas Municipio 24 kmAñasco Municipio 25 kmRincón Municipio 28 kmSabana Grande Municipio 30 kmLas Marías Municipio 31 kmAguada 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
5:44 pm AST on 6 January 2021 ()
Where
5 km (3 mi) west-northwest of Puerto Real, PR · earthquakes near Puerto Real
Magnitude
M 1.9 (md)
Depth
18 km below the surface
Felt
no reports yet
Nearest
Cabo Rojo Municipio, 11 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2071 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Puerto Real, 5 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.

Earthquakes near other towns within 30 km: Cabo Rojo, Boquerón, Hormigueros, Pole Ojea, Monte Grande, Mayagüez.

How big was it?

This earthquake released about 25 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 620,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 440,000× the energy of this one
  3. Around the size people start to feel M 3.0 39× the energy of this one
  4. This earthquake M 1.9 about 25 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 4,900,000 times the energy of this one.

Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:

  1. 6.3 6 km WNW of Aguadilla, Puerto Rico · 40 km N of this epicentre
  2. 5.8 4 km E of Moca, Puerto Rico · 39 km NNE of this epicentre
  3. 5.2 19 km SW of Stella, Puerto Rico · 18 km NW of this epicentre
  4. 5.1 21 km SW of Stella, Puerto Rico · 17 km NW 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 18.0861, -67.2358. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cabo Rojo Municipio, PR 11 km (7 mi) SSE earthquakes near Cabo Rojo Municipio
Hormigueros Municipio, PR 14 km (9 mi) ENE earthquakes near Hormigueros Municipio
San Germán Municipio, PR 21 km (13 mi) E earthquakes near San Germán Municipio
Lajas Municipio, PR 24 km (15 mi) ESE earthquakes near Lajas Municipio
Añasco Municipio, PR 25 km (15 mi) NNE earthquakes near Añasco Municipio
Rincón Municipio, PR 28 km (17 mi) N earthquakes near Rincón 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. 2.1 4 km ENE of La Parguera, Puerto Rico
  2. 1.6 4 km W of Fuig, Puerto Rico
  3. 2.2 2 km SSW of Indios, Puerto Rico
  4. 2.4 4 km S of Indios, Puerto Rico
  5. 2.6 3 km WSW of Fuig, Puerto Rico
  6. 2.0 4 km SSE of Guánica, Puerto Rico
  7. 1.8 5 km WSW of Guánica, Puerto Rico
  8. 1.7 4 km E of La Parguera, Puerto Rico
  9. 2.0 12 km S of Guánica, Puerto Rico
  10. 2.0 2 km NW of Guayanilla, Puerto Rico
  11. 2.3 4 km NE of La Parguera, Puerto Rico
  12. 2.1 7 km SE of Maria Antonia, Puerto Rico
  13. 1.9 6 km SE of Maria Antonia, Puerto Rico
  14. 2.0 1 km SSW of Indios, Puerto Rico
  15. 2.2 4 km ESE 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.