QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0md

Earthquake near La Parguera, PR

No earthquake was likely felt in La Parguera in the 24 hours to 11:26 am AST (15:26 UTC). The last one was M 2.1, 9 km (5 mi) WNW, at 11:57 pm AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near La Parguera

This page: a magnitude 3.0 earthquake was recorded 7 km (4 mi) east of La Parguera, PR, at 5:28 pm AST on 31 July 2021 (21:28 UTC), 5.0 km deep. 1 person has reported feeling it to USGS.

USGS: 6 km E of La Parguera, Puerto Rico

38 km (24 mi) W of Ponce, PR · 30 km (19 mi) SE of Mayagüez, PR

5:28 pm AST, Jul 31, 2021 · · 5.0 km deep · released about 1,100 lb of TNT

Every earthquake near La Parguera Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lajas Municipio 6 kmGuánica Municipio 7 kmSabana Grande Municipio 12 kmSan Germán Municipio 15 kmYauco Municipio 18 kmGuayanilla Municipio 20 kmCabo Rojo Municipio 21 kmHormigueros Municipio 22 kmMaricao Municipio 22 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
5:28 pm AST on 31 July 2021 ()
Where
7 km (4 mi) east of La Parguera, PR · earthquakes near La Parguera
Magnitude
M 3.0 (md)
Depth
5.0 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Lajas Municipio, 6 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1929 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 38 km (24 mi) from the epicentre. In La Parguera, 7 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: San Germán 13 km, intensity III · Yauco 15 km, intensity III · Guayanilla 21 km, intensity II · Pole Ojea 21 km, intensity II · Magas Arriba 23 km, intensity II · Puerto Real 24 km, intensity II · Tallaboa 28 km, intensity II · Mayagüez 30 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,100 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 310,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 14,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,800× the energy of this one
  4. This earthquake M 3.0 about 1,100 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 110,000 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 5.8 4 km E of Moca, Puerto Rico · 48 km N of this epicentre
  2. 5.2 19 km SW of Stella, Puerto Rico · 47 km WNW of this epicentre
  3. 5.1 21 km SW of Stella, Puerto Rico · 46 km WNW 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 17.9788, -66.9840. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lajas Municipio, PR 6 km (4 mi) W earthquakes near Lajas Municipio
Guánica Municipio, PR 7 km (5 mi) ESE earthquakes near Guánica Municipio
Sabana Grande Municipio, PR 12 km (8 mi) NNE earthquakes near Sabana Grande Municipio
San Germán Municipio, PR 15 km (10 mi) NNW earthquakes near San Germán Municipio
Yauco Municipio, PR 18 km (11 mi) NE earthquakes near Yauco Municipio
Guayanilla Municipio, PR 20 km (12 mi) E earthquakes near Guayanilla 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. 2.4 2 km SSE of Capitanejo, Puerto Rico
  2. 3.1 4 km SSW of Indios, Puerto Rico
  3. 2.2 3 km E of Pole Ojea, Puerto Rico
  4. 3.1 3 km E of Pole Ojea, Puerto Rico
  5. 2.1 5 km WSW of La Parguera, Puerto Rico
  6. 3.0 6 km S of Guánica, Puerto Rico
  7. 2.5 10 km SW of La Parguera, Puerto Rico
  8. 2.4 5 km SSW of Guánica, Puerto Rico
  9. 2.9 2 km SW of Indios, Puerto Rico
  10. 2.7 3 km WSW of Tallaboa, Puerto Rico
  11. 2.7 7 km SW of Guánica, Puerto Rico
  12. 2.8 2 km WSW of Guánica, Puerto Rico
  13. 2.6 4 km SSW of Guánica, Puerto Rico
  14. 2.6 6 km E of La Parguera, Puerto Rico
  15. 2.4 6 km S 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.