QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Earthquake near Aguadilla, PR

No earthquake was likely felt in Aguadilla in the 24 hours to 10:17 am AST (14:17 UTC). The last one was M 3.5, 4 km (3 mi) SE, at 12:03 am AST on 6 November 2026, estimated intensity II (weak) in town. Every earthquake near Aguadilla

This page: a magnitude 3.1 earthquake was recorded 47 km (29 mi) north-northwest of Aguadilla, PR, at 11:42 pm AST on 18 February 2018 (03:42 UTC), 11 km deep.

USGS: 43 km NW of San Antonio, Puerto Rico

11:42 pm AST, Feb 18, 2018 · · 11 km deep · released about 1,200 lb of TNT

Every earthquake near Aguadilla Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Aguadilla Municipio 42 kmIsabela Municipio 49 kmAguada Municipio 51 kmRincón Municipio 53 kmMoca Municipio 55 kmQuebradillas Municipio 57 kmAñasco Municipio 62 kmCamuy Municipio 64 kmSan Sebastián Municipio 66 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
11:42 pm AST on 18 February 2018 ()
Where
47 km (29 mi) north-northwest of Aguadilla, PR · earthquakes near Aguadilla
Magnitude
M 3.1 (md)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Aguadilla Municipio, 42 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3096 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, people at rest would likely notice it out to about 38 km (24 mi) from the epicentre. In Aguadilla, 47 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.

How big was it?

This earthquake released about 1,200 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 290,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 13,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,100× the energy of this one
  4. This earthquake M 3.1 about 1,200 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.2× more

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 72 times the energy of this one.

Before 2016, the USGS record lists 15 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.7 45 km N of San Antonio, Puerto Rico · 25 km ENE of this epicentre
  2. 7.1 24 km NNW of San Antonio, Puerto Rico · 19 km SE of this epicentre
  3. 6.4 32 km NW of Aguadilla, Puerto Rico · 23 km SSW of this epicentre
  4. 6.3 6 km WNW of Aguadilla, Puerto Rico · 43 km SSE of this epicentre
  5. 6.1 15 km WNW of San Antonio, Puerto Rico · 31 km SSE 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 18.8120, -67.3306. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Aguadilla Municipio, PR 42 km (26 mi) SSE earthquakes near Aguadilla Municipio
Isabela Municipio, PR 49 km (31 mi) SE earthquakes near Isabela Municipio
Aguada Municipio, PR 51 km (32 mi) SSE earthquakes near Aguada Municipio
Rincón Municipio, PR 53 km (33 mi) S earthquakes near Rincón Municipio
Moca Municipio, PR 55 km (34 mi) SSE earthquakes near Moca Municipio
Quebradillas Municipio, PR 57 km (36 mi) SE earthquakes near Quebradillas Municipio

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

Aftershocks so far

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

  1. 3.0 48 km NW of San Antonio, Puerto Rico
  2. 2.5 58 km NNW of San Antonio, Puerto Rico
  3. 3.1 82 km N of San Antonio, Puerto Rico
  4. 2.8 34 km NNW of San Antonio, Puerto Rico
  5. 2.7 15 km NW of San Antonio, Puerto Rico
  6. 2.4 36 km WNW of Rincón, Puerto Rico
  7. 2.6 11 km NE of Isabela, Puerto Rico
  8. 2.5 17 km NW of San Antonio, Puerto Rico
  9. 3.0 45 km N of Isabela, Puerto Rico
  10. 2.9 37 km NNW of San Antonio, Puerto Rico
  11. 2.5 36 km NW of Aguadilla, Puerto Rico
  12. 2.7 42 km NNW of San Antonio, Puerto Rico
  13. 2.5 22 km WNW of Rincón, Puerto Rico
  14. 3.0 53 km NNE of Isabela, Puerto Rico
  15. 2.8 25 km NW of Rincón, 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.