QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

Earthquake near Sumidero, PR

No earthquake was likely felt in Sumidero in the 24 hours to 11:59 pm AST (03:59 UTC). The last one was M 4.1, 89 km (55 mi) ESE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Sumidero

This page: a magnitude 2.4 earthquake was recorded 3 km (2 mi) southwest of Sumidero, PR, at 1:25 am AST on 20 June 2018 (05:25 UTC), 79 km deep.

USGS: 2 km SW of Sumidero, Puerto Rico

24 km (15 mi) SSW of San Juan, PR · 12 km (7 mi) WSW of Caguas, PR

1:25 am AST, Jun 20, 2018 · · 79 km deep · released about 110 lb of TNT

Every earthquake near Sumidero Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Cidra Municipio 3 kmAguas Buenas Municipio 6 kmComerío Municipio 8 kmCaguas Municipio 10 kmCayey Municipio 11 kmAibonito Municipio 15 kmNaranjito Municipio 15 kmGuaynabo Municipio 16 kmBayamón Municipio 17 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
1:25 am AST on 20 June 2018 ()
Where
3 km (2 mi) southwest of Sumidero, PR · earthquakes near Sumidero
Magnitude
M 2.4 (md)
Depth
79 km below the surface
Felt
no reports yet
Nearest
Cidra Municipio, 3 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3068 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 Sumidero, 3 km away, the estimate is intensity I (not felt). 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: Santa Clara, Cidra, Parcelas La Milagrosa, Parcelas Nuevas, Aguas Buenas, Comerío.

How big was it?

This earthquake released about 110 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 140,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 99,000× the energy of this one
  3. Around the size people start to feel M 3.0 8.8× the energy of this one
  4. This earthquake M 2.4 about 110 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 4.6 on 2016-12-05 — about 2,200 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 7 km N of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 39 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 18.2016, -66.1466. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cidra Municipio, PR 3 km (2 mi) SSW earthquakes near Cidra Municipio
Aguas Buenas Municipio, PR 6 km (4 mi) NNE earthquakes near Aguas Buenas Municipio
Comerío Municipio, PR 8 km (5 mi) WNW earthquakes near Comerío Municipio
Caguas Municipio, PR 10 km (6 mi) E earthquakes near Caguas Municipio
Cayey Municipio, PR 11 km (7 mi) S earthquakes near Cayey Municipio
Aibonito Municipio, PR 15 km (9 mi) WSW earthquakes near Aibonito Municipio

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

Aftershocks so far

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

  1. 2.7 4 km ESE of Florida, Puerto Rico
  2. 3.0 4 km ESE of Bayamon, Puerto Rico
  3. 2.6 3 km SSE of Guaynabo, Puerto Rico
  4. 2.3 9 km SSW of Emajagua, Puerto Rico
  5. 2.0 11 km S of Emajagua, Puerto Rico
  6. 2.5 10 km SSW of Emajagua, Puerto Rico
  7. 2.8 3 km NNE of Naranjito, Puerto Rico
  8. 2.0 1 km NE of Sabana Seca, Puerto Rico
  9. 2.9 5 km SE of Cataño, Puerto Rico
  10. 2.1 7 km E of Naranjito, Puerto Rico
  11. 1.5 2 km N of Coquí, Puerto Rico
  12. 2.2 2 km NNE of Coquí, Puerto Rico
  13. 2.0 1 km W of Guayabal, Puerto Rico
  14. 2.1 2 km E of Juana Díaz, Puerto Rico
  15. 2.3 2 km SW of Bajandas, 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.