QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Sumidero, PR

No earthquake was likely felt in Sumidero in the 24 hours to 9:07 pm AST (01:07 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 1.8 earthquake was recorded in Sumidero, PR, at 1:07 pm AST on 16 December 2018 (17:07 UTC), 15 km deep.

USGS: 1 km NNW of Sumidero, Puerto Rico

21 km (13 mi) SSW of San Juan, PR · 10 km (6 mi) W of Caguas, PR

1:07 pm AST, Dec 16, 2018 · · 15 km deep · released about 17 lb of TNT

Every earthquake near Sumidero Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Aguas Buenas Municipio 3 kmCidra Municipio 7 kmComerío Municipio 9 kmCaguas Municipio 9 kmGuaynabo Municipio 13 kmBayamón Municipio 13 kmNaranjito Municipio 14 kmCayey Municipio 14 kmGurabo 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
1:07 pm AST on 16 December 2018 ()
Where
in Sumidero, PR · earthquakes near Sumidero
Magnitude
M 1.8 (md)
Depth
15 km below the surface
Felt
no reports yet
Nearest
Aguas Buenas Municipio, 3 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2887 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. 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, Aguas Buenas, Cidra, Parcelas La Milagrosa, Caguas, Comerío.

How big was it?

This earthquake released about 17 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 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 14,000 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 · 3 km N of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 37 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 18.2325, -66.1345. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Aguas Buenas Municipio, PR 3 km (2 mi) NNE earthquakes near Aguas Buenas Municipio
Cidra Municipio, PR 7 km (4 mi) SSW earthquakes near Cidra Municipio
Comerío Municipio, PR 9 km (6 mi) W earthquakes near Comerío Municipio
Caguas Municipio, PR 9 km (6 mi) ESE earthquakes near Caguas Municipio
Guaynabo Municipio, PR 13 km (8 mi) N earthquakes near Guaynabo Municipio
Bayamón Municipio, PR 13 km (8 mi) NNW earthquakes near Bayamón Municipio

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

Aftershocks so far

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

  1. 2.7 2 km SW of H. Rivera Colon, Puerto Rico
  2. 2.0 20 km NE of San Juan, Puerto Rico
  3. 2.6 3 km N of Cidra, Puerto Rico
  4. 2.7 5 km S of Jayuya, Puerto Rico
  5. 2.5 6 km ESE of San Juan, Puerto Rico
  6. 1.7 3 km SSE of Santa Isabel, Puerto Rico
  7. 2.1 0 km SW of Toa Alta, Puerto Rico
  8. 2.9 13 km NNW of Brenas, Puerto Rico
  9. 1.9 5 km SSE of Central Aguirre, Puerto Rico
  10. 1.9 6 km WNW of Palomas, Puerto Rico
  11. 1.5 5 km SSW of Guaynabo, Puerto Rico
  12. 2.5 12 km N of Brenas, Puerto Rico
  13. 1.6 1 km SSE of Capitanejo, Puerto Rico
  14. 3.0 2 km ENE of Guaynabo, Puerto Rico
  15. 1.9 4 km E of Barranquitas, 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.