QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Boquerón, PR

No earthquake was likely felt in Boquerón in the 24 hours to 12:10 pm AST (16:10 UTC). The last one was M 2.1, 6 km (4 mi) ESE, at 11:57 pm AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Boquerón

This page: a magnitude 1.9 earthquake was recorded 4 km (3 mi) southeast of Boquerón, PR, at 6:09 am AST on 26 July 2021 (10:09 UTC), 21 km deep.

USGS: 4 km SE of Boquerón, Puerto Rico

22 km (14 mi) S of Mayagüez, PR · 123 km (76 mi) WSW of San Juan, PR

6:09 am AST, Jul 26, 2021 · · 21 km deep · released about 25 lb of TNT

Every earthquake near Boquerón Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Cabo Rojo Municipio 4 kmLajas Municipio 11 kmHormigueros Municipio 15 kmSan Germán Municipio 16 kmSabana Grande Municipio 23 kmGuánica Municipio 24 kmMaricao Municipio 29 kmLas Marías Municipio 31 kmYauco Municipio 32 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
6:09 am AST on 26 July 2021 ()
Where
4 km (3 mi) southeast of Boquerón, PR · earthquakes near Boquerón
Magnitude
M 1.9 (md)
Depth
21 km below the surface
Felt
no reports yet
Nearest
Cabo Rojo Municipio, 4 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1934 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 Boquerón, 4 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: Pole Ojea, Palmarejo, Puerto Real, Cabo Rojo, Monte Grande, Lajas.

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 3.0 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 420,000× the energy of this one
  3. Around the size people start to feel M 3.0 38× 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 4,700,000 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 · 50 km N of this epicentre
  2. 5.8 4 km E of Moca, Puerto Rico · 45 km N of this epicentre
  3. 5.2 19 km SW of Stella, Puerto Rico · 32 km NW of this epicentre
  4. 5.1 21 km SW of Stella, Puerto Rico · 31 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 17.9995, -67.1431. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cabo Rojo Municipio, PR 4 km (2 mi) W earthquakes near Cabo Rojo Municipio
Lajas Municipio, PR 11 km (7 mi) ESE earthquakes near Lajas Municipio
Hormigueros Municipio, PR 15 km (10 mi) N earthquakes near Hormigueros Municipio
San Germán Municipio, PR 16 km (10 mi) NE earthquakes near San Germán Municipio
Sabana Grande Municipio, PR 23 km (14 mi) ENE earthquakes near Sabana Grande Municipio
Guánica Municipio, PR 24 km (15 mi) ESE earthquakes near Guánica Municipio

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

Aftershocks so far

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

  1. 3.2 4 km WSW of La Parguera, Puerto Rico
  2. 2.3 5 km WSW of La Parguera, Puerto Rico
  3. 3.0 5 km WSW of La Parguera, Puerto Rico
  4. 3.1 6 km W of La Parguera, Puerto Rico
  5. 1.7 2 km W of Guayanilla, Puerto Rico
  6. 2.6 2 km ESE of Maria Antonia, Puerto Rico
  7. 2.8 5 km WSW of La Parguera, Puerto Rico
  8. 3.4 8 km WSW of La Parguera, Puerto Rico
  9. 3.4 7 km WSW of La Parguera, Puerto Rico
  10. 1.5 5 km SW of Palmarejo, Puerto Rico
  11. 2.1 6 km WSW of La Parguera, Puerto Rico
  12. 2.5 4 km WSW of La Parguera, Puerto Rico
  13. 2.6 6 km SSE of Maria Antonia, Puerto Rico
  14. 2.5 10 km SSE of Guánica, Puerto Rico
  15. 2.6 5 km WSW 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.