QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near San Sebastián, PR

No earthquake was likely felt in San Sebastián in the 24 hours to 11:32 am AST (15:32 UTC). The last one was M 3.4, 50 km (31 mi) N, at 9:00 pm AST on 27 October 2026, estimated intensity II (weak) in town. Every earthquake near San Sebastián

This page: a magnitude 1.9 earthquake was recorded 5 km (3 mi) west-northwest of San Sebastián, PR, at 10:51 pm AST on 23 June 2019 (02:51 UTC), 22 km deep.

USGS: 4 km WNW of San Sebastián, Puerto Rico

21 km (13 mi) NE of Mayagüez, PR · 102 km (63 mi) W of San Juan, PR

10:51 pm AST, Jun 23, 2019 · · 22 km deep · released about 24 lb of TNT

Every earthquake near San Sebastián Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Moca Municipio 6 kmSan Sebastián Municipio 7 kmAñasco Municipio 13 kmIsabela Municipio 14 kmLas Marías Municipio 15 kmQuebradillas Municipio 16 kmAguada Municipio 17 kmAguadilla Municipio 18 kmLares Municipio 19 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
10:51 pm AST on 23 June 2019 ()
Where
5 km (3 mi) west-northwest of San Sebastián, PR · earthquakes near San Sebastián
Magnitude
M 1.9 (md)
Depth
22 km below the surface
Felt
no reports yet
Nearest
Moca Municipio, 6 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2697 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 San Sebastián, 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: Moca, Aceitunas, Mora, Juncal, Espino, Cacao.

How big was it?

This earthquake released about 24 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 5.8 640,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 450,000× the energy of this one
  3. Around the size people start to feel M 3.0 40× the energy of this one
  4. This earthquake M 1.9 about 24 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 4.3 on 2017-10-14 — about 3,600 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 24 km NNW of San Antonio, Puerto Rico · 42 km NNW of this epicentre
  2. 6.4 32 km NW of Aguadilla, Puerto Rico · 47 km NW of this epicentre
  3. 6.3 6 km WNW of Aguadilla, Puerto Rico · 22 km WNW of this epicentre
  4. 6.1 15 km WNW of San Antonio, Puerto Rico · 31 km NW of this epicentre
  5. 6.1 18 km NNW of San Antonio, Puerto Rico · 35 km NNW 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 18.3545, -67.0300. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Moca Municipio, PR 6 km (4 mi) WNW earthquakes near Moca Municipio
San Sebastián Municipio, PR 7 km (4 mi) ESE earthquakes near San Sebastián Municipio
Añasco Municipio, PR 13 km (8 mi) SW earthquakes near Añasco Municipio
Isabela Municipio, PR 14 km (9 mi) N earthquakes near Isabela Municipio
Las Marías Municipio, PR 15 km (9 mi) SSE earthquakes near Las Marías Municipio
Quebradillas Municipio, PR 16 km (10 mi) NE earthquakes near Quebradillas Municipio

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

Aftershocks so far

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

  1. 2.0 6 km NNE of Sabana Eneas, Puerto Rico
  2. 2.3 3 km ENE of Espino, Puerto Rico
  3. 1.9 8 km N of Yauco, Puerto Rico
  4. 2.5 25 km NW of Rincón, Puerto Rico
  5. 2.5 5 km NNE of Isabela, Puerto Rico
  6. 2.1 2 km E of Mayagüez, Puerto Rico
  7. 1.7 5 km NNE of Sabana Grande, Puerto Rico
  8. 1.8 4 km SSW of Añasco, Puerto Rico
  9. 1.9 6 km NW of Adjuntas, Puerto Rico
  10. 1.6 5 km NNE of Sabana Grande, Puerto Rico
  11. 2.4 5 km NNE of Sabana Grande, Puerto Rico
  12. 1.6 7 km ESE of Las Marías, Puerto Rico
  13. 2.0 8 km W of Maricao, Puerto Rico
  14. 2.0 8 km WSW of Guánica, Puerto Rico
  15. 1.9 25 km NNE of Isabela, 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.