QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Mariano Colón, PR

No earthquake was likely felt in Mariano Colón in the 24 hours to 10:59 pm AST (02:59 UTC). The last one was M 2.2, in Mariano Colón, at 5:05 pm AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Mariano Colón

This page: a magnitude 1.6 earthquake was recorded in Mariano Colón, PR, at 5:05 am AST on 8 May 2018 (09:05 UTC), 8.0 km deep.

USGS: 1 km SSW of Mariano Colón, Puerto Rico

52 km (32 mi) SSW of San Juan, PR · 31 km (19 mi) E of Ponce, PR

5:05 am AST, May 8, 2018 · · 8.0 km deep · released about 9 lb of TNT

Every earthquake near Mariano Colón Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Isabel Municipio 9 kmSalinas Municipio 9 kmCoamo Municipio 10 kmAibonito Municipio 15 kmJuana Díaz Municipio 16 kmVillalba Municipio 19 kmBarranquitas Municipio 21 kmGuayama Municipio 21 kmCayey 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
5:05 am AST on 8 May 2018 ()
Where
in Mariano Colón, PR · earthquakes near Mariano Colón
Magnitude
M 1.6 (md)
Depth
8.0 km below the surface
Felt
no reports yet
Nearest
Santa Isabel Municipio, 9 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3110 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. 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: Coamo 8 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 9 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 9 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 27,000 times the energy of this one.

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

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 35 km NE 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 18.0136, -66.3356. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Isabel Municipio, PR 9 km (5 mi) SW earthquakes near Santa Isabel Municipio
Salinas Municipio, PR 9 km (6 mi) ESE earthquakes near Salinas Municipio
Coamo Municipio, PR 10 km (6 mi) NNW earthquakes near Coamo Municipio
Aibonito Municipio, PR 15 km (9 mi) NNE earthquakes near Aibonito Municipio
Juana Díaz Municipio, PR 16 km (10 mi) W earthquakes near Juana Díaz Municipio
Villalba Municipio, PR 19 km (12 mi) NW earthquakes near Villalba Municipio

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

Aftershocks so far

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

  1. 2.3 3 km SE of Magas Arriba, Puerto Rico
  2. 1.7 3 km ESE of G. L. Garcia, Puerto Rico
  3. 1.8 3 km WSW of Tallaboa, Puerto Rico
  4. 1.6 3 km E of Tallaboa, Puerto Rico
  5. 1.6 4 km SW of Capitanejo, Puerto Rico
  6. 2.2 4 km WSW of Capitanejo, Puerto Rico
  7. 2.5 3 km SW of Capitanejo, Puerto Rico
  8. 2.6 6 km NE of Comerío, Puerto Rico
  9. 2.0 1 km E of Parcelas Nuevas, Puerto Rico
  10. 2.2 3 km NNW of Orocovis, Puerto Rico
  11. 1.7 1 km ESE of Guayabal, Puerto Rico
  12. 1.8 5 km NNW of Yaurel, Puerto Rico
  13. 1.8 5 km SSW of Salinas, Puerto Rico
  14. 2.6 3 km S of Palo Seco, Puerto Rico
  15. 2.7 8 km SSW of Emajagua, 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.