QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6md

Earthquake near San Juan, PR

No earthquake was likely felt in San Juan in the 24 hours to 5:33 pm AST (21:33 UTC). The last one was M 4.1, 99 km (62 mi) SE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near San Juan

This page: a magnitude 2.6 earthquake was recorded 45 km (28 mi) west-southwest of San Juan, PR, at 6:37 pm AST on 31 January 2018 (22:37 UTC), 31 km deep.

USGS: Puerto Rico region

45 km (28 mi) WSW of San Juan, PR · 33 km (20 mi) NNE of Ponce, PR

6:37 pm AST, Jan 31, 2018 · · 31 km deep · released about 280 lb of TNT

Every earthquake near San Juan Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orocovis Municipio 4 kmCiales Municipio 8 kmMorovis Municipio 9 kmVillalba Municipio 13 kmJayuya Municipio 14 kmCorozal Municipio 15 kmBarranquitas Municipio 17 kmFlorida Municipio 17 kmCoamo 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
6:37 pm AST on 31 January 2018 ()
Where
45 km (28 mi) west-southwest of San Juan, PR · earthquakes near San Juan
Magnitude
M 2.6 (md)
Depth
31 km below the surface
Felt
no reports yet
Nearest
Orocovis Municipio, 4 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3206 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In San Juan, 45 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: Ciales, Morovis, Franquez, Barahona, Villalba, Jayuya.

How big was it?

This earthquake released about 280 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 53,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 38,000× the energy of this one
  3. Around the size people start to feel M 3.0 3.3× the energy of this one
  4. This earthquake M 2.6 about 280 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.

Where

Epicentre 18.2475, -66.4591. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orocovis Municipio, PR 4 km (2 mi) SE earthquakes near Orocovis Municipio
Ciales Municipio, PR 8 km (5 mi) NW earthquakes near Ciales Municipio
Morovis Municipio, PR 9 km (5 mi) NNE earthquakes near Morovis Municipio
Villalba Municipio, PR 13 km (8 mi) S earthquakes near Villalba Municipio
Jayuya Municipio, PR 14 km (9 mi) WSW earthquakes near Jayuya Municipio
Corozal Municipio, PR 15 km (10 mi) ENE earthquakes near Corozal Municipio

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

Aftershocks so far

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

  1. 1.9 11 km SSW of Potala Pastillo, Puerto Rico
  2. 1.8 9 km ESE of Maricao, Puerto Rico
  3. 2.7 4 km WNW of San Juan, Puerto Rico
  4. 2.0 9 km SSW of Central Aguirre, Puerto Rico
  5. 1.6 Puerto Rico region
  6. 1.8 4 km SSE of Adjuntas, Puerto Rico
  7. 2.4 7 km NNE of Garrochales, Puerto Rico
  8. 1.9 9 km NNE of Yauco, Puerto Rico
  9. 2.5 23 km NNW of Tierras Nuevas Poniente, Puerto Rico
  10. 2.7 1 km NE of Jauca, Puerto Rico
  11. 1.9 7 km WSW of Orocovis, Puerto Rico
  12. 2.2 5 km SSW of Adjuntas, Puerto Rico
  13. 1.6 7 km SSW of Ponce, Puerto Rico
  14. 1.7 2 km S of Santo Domingo, Puerto Rico
  15. 3.2 6 km ENE of Jayuya, 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.