QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Adjuntas, PR

No earthquake was likely felt in Adjuntas in the 24 hours to 4:28 pm AST (20:28 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 1.9 earthquake was recorded 6 km (4 mi) northwest of Adjuntas, PR, at 11:04 pm AST on 31 July 2019 (03:04 UTC), 12 km deep.

USGS: 6 km NW of Adjuntas, Puerto Rico

27 km (17 mi) NW of Ponce, PR

11:04 pm AST, Jul 31, 2019 · · 12 km deep · released about 22 lb of TNT

Every earthquake near Adjuntas Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Adjuntas Municipio 2 kmUtuado Municipio 11 kmLares Municipio 14 kmYauco Municipio 15 kmMaricao Municipio 18 kmPeñuelas Municipio 19 kmJayuya Municipio 19 kmGuayanilla Municipio 21 kmLas Marías 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
11:04 pm AST on 31 July 2019 ()
Where
6 km (4 mi) northwest of Adjuntas, PR · earthquakes near Adjuntas
Magnitude
M 1.9 (md)
Depth
12 km below the surface
Felt
no reports yet
Nearest
Adjuntas Municipio, 2 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2660 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 9 km (6 mi) from the epicentre. In Adjuntas, 6 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 6 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 22 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 5.8 680,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 480,000× the energy of this one
  3. Around the size people start to feel M 3.0 43× the energy of this one
  4. This earthquake M 1.9 about 22 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 2 earthquakes of M5 or more within 50 km:

  1. 5.8 12 km N of Garrochales, Puerto Rico · 46 km NNE of this epicentre
  2. 5.8 4 km E of Moca, Puerto Rico · 39 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 18.1953, -66.7698. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Adjuntas Municipio, PR 2 km (1 mi) SE earthquakes near Adjuntas Municipio
Utuado Municipio, PR 11 km (7 mi) NE earthquakes near Utuado Municipio
Lares Municipio, PR 14 km (9 mi) NW earthquakes near Lares Municipio
Yauco Municipio, PR 15 km (10 mi) SW earthquakes near Yauco Municipio
Maricao Municipio, PR 18 km (11 mi) W earthquakes near Maricao Municipio
Peñuelas Municipio, PR 19 km (12 mi) SSE earthquakes near Peñuelas Municipio

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

Aftershocks so far

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

  1. 1.8 10 km SSE of Ponce, Puerto Rico
  2. 2.7 12 km N of Hatillo, Puerto Rico
  3. 2.2 1 km NNW of Pole Ojea, Puerto Rico
  4. 1.6 8 km W of Mayagüez, Puerto Rico
  5. 2.0 2 km S of Mayagüez, Puerto Rico
  6. 1.9 1 km ENE of La Playa, Puerto Rico
  7. 1.8 2 km WNW of Guayanilla, Puerto Rico
  8. 1.7 12 km SSE of Ponce, Puerto Rico
  9. 1.8 7 km SW of Jayuya, Puerto Rico
  10. 2.4 12 km SSE of Ponce, Puerto Rico
  11. 1.6 3 km SW of Puerto Real, Puerto Rico
  12. 2.5 4 km E of Mayagüez, Puerto Rico
  13. 2.1 12 km S of Ponce, Puerto Rico
  14. 2.4 12 km SSE of Ponce, Puerto Rico
  15. 1.9 Puerto Rico region

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.