QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Adjuntas, PR

No earthquake was likely felt in Adjuntas in the 24 hours to 3:14 am AST (07:14 UTC). The last one was M 3.0, 31 km (19 mi) SSW, at 3:45 am AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Adjuntas

This page: a magnitude 1.8 earthquake was recorded 5 km (3 mi) south of Adjuntas, PR, at 9:07 pm AST on 21 April 2019 (01:07 UTC), 7.0 km deep.

USGS: 5 km S of Adjuntas, Puerto Rico

17 km (10 mi) NW of Ponce, PR

9:07 pm AST, Apr 21, 2019 · · 7.0 km deep · released about 16 lb of TNT

Every earthquake near Adjuntas Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Adjuntas Municipio 8 kmPeñuelas Municipio 10 kmGuayanilla Municipio 15 kmYauco Municipio 15 kmUtuado Municipio 17 kmPonce Municipio 18 kmJayuya Municipio 18 kmMaricao Municipio 23 kmLares Municipio 24 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
9:07 pm AST on 21 April 2019 ()
Where
5 km (3 mi) south of Adjuntas, PR · earthquakes near Adjuntas
Magnitude
M 1.8 (md)
Depth
7.0 km below the surface
Felt
no reports yet
Nearest
Adjuntas Municipio, 8 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2761 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Adjuntas, 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.

Likely felt in: Adjuntas 5 km, intensity II · Tallaboa Alta 7 km, intensity II · Magas Arriba 12 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.8 4 km E of Moca, Puerto Rico · 48 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 18.1148, -66.7230. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Adjuntas Municipio, PR 8 km (5 mi) NNW earthquakes near Adjuntas Municipio
Peñuelas Municipio, PR 10 km (6 mi) S earthquakes near Peñuelas Municipio
Guayanilla Municipio, PR 15 km (9 mi) SSW earthquakes near Guayanilla Municipio
Yauco Municipio, PR 15 km (9 mi) WSW earthquakes near Yauco Municipio
Utuado Municipio, PR 17 km (11 mi) N earthquakes near Utuado Municipio
Ponce Municipio, PR 18 km (11 mi) SE earthquakes near Ponce Municipio

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

Aftershocks so far

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

  1. 1.6 5 km ESE of Boquerón, Puerto Rico
  2. 1.8 10 km SSW of Guánica, Puerto Rico
  3. 2.5 5 km ESE of Piedra Gorda, Puerto Rico
  4. 1.8 4 km W of Capitanejo, Puerto Rico
  5. 2.1 1 km N of Aguilita, Puerto Rico
  6. 2.1 0 km E of Yauco, Puerto Rico
  7. 1.5 3 km W of Palmarejo, Puerto Rico
  8. 1.7 13 km SSW of Guánica, Puerto Rico
  9. 1.6 5 km S of Piedra Gorda, Puerto Rico
  10. 1.8 3 km N of Yauco, Puerto Rico
  11. 1.7 2 km E of Hormigueros, Puerto Rico
  12. 1.5 5 km SE of Adjuntas, Puerto Rico
  13. 1.6 7 km NE of Sabana Grande, Puerto Rico
  14. 2.0 4 km SE of Maria Antonia, Puerto Rico
  15. 1.9 3 km S of Maricao, 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.