QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Hatillo, PR

No earthquake was likely felt in Hatillo in the 24 hours to 7:25 pm AST (23:25 UTC). The last one was M 3.4, 40 km (25 mi) NW, at 9:00 pm AST on 27 October 2026, estimated intensity II (weak) in town. Every earthquake near Hatillo

This page: a magnitude 1.8 earthquake was recorded 3 km (2 mi) northeast of Hatillo, PR, at 1:35 am AST on 4 August 2018 (05:35 UTC), 15 km deep.

USGS: 3 km NE of Hatillo, Puerto Rico

9 km (6 mi) NW of Arecibo, PR · 79 km (49 mi) W of San Juan, PR

1:35 am AST, Aug 4, 2018 · · 15 km deep · released about 14 lb of TNT

Every earthquake near Hatillo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Hatillo Municipio 7 kmCamuy Municipio 9 kmQuebradillas Municipio 14 kmArecibo Municipio 16 kmIsabela Municipio 22 kmSan Sebastián Municipio 26 kmBarceloneta Municipio 26 kmLares Municipio 27 kmUtuado Municipio 28 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
1:35 am AST on 4 August 2018 ()
Where
3 km (2 mi) northeast of Hatillo, PR · earthquakes near Hatillo
Magnitude
M 1.8 (md)
Depth
15 km below the surface
Felt
no reports yet
Nearest
Hatillo Municipio, 7 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3023 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 Hatillo, 3 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: Carrizales, Camuy, Corcovado, Rafael Gonzalez, Arecibo, Rafael Capo.

How big was it?

This earthquake released about 14 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 24 km NNW of San Antonio, Puerto Rico · 46 km WNW of this epicentre
  2. 6.3 6 km WNW of Aguadilla, Puerto Rico · 44 km W of this epicentre
  3. 6.1 15 km WNW of San Antonio, Puerto Rico · 45 km W of this epicentre
  4. 6.1 18 km NNW of San Antonio, Puerto Rico · 42 km WNW of this epicentre
  5. 5.8 12 km N of Garrochales, Puerto Rico · 26 km ENE 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 18.5076, -66.8053. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Hatillo Municipio, PR 7 km (5 mi) S earthquakes near Hatillo Municipio
Camuy Municipio, PR 9 km (6 mi) SW earthquakes near Camuy Municipio
Quebradillas Municipio, PR 14 km (9 mi) WSW earthquakes near Quebradillas Municipio
Arecibo Municipio, PR 16 km (10 mi) ESE earthquakes near Arecibo Municipio
Isabela Municipio, PR 22 km (14 mi) W earthquakes near Isabela Municipio
San Sebastián Municipio, PR 26 km (16 mi) SW earthquakes near San Sebastián Municipio

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

Aftershocks so far

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

  1. 2.0 6 km SW of Maricao, Puerto Rico
  2. 2.1 Mona Passage
  3. 2.1 0 km NE of Ciales, Puerto Rico
  4. 2.5 4 km E of Isabela, Puerto Rico
  5. 2.7 10 km NNE of Isabela, Puerto Rico
  6. 1.8 3 km NW of Sabana Grande, Puerto Rico
  7. 2.1 3 km WSW of Maricao, Puerto Rico
  8. 2.1 5 km WNW of Maricao, Puerto Rico
  9. 2.8 4 km NNW of Sabana, Puerto Rico
  10. 2.7 26 km NNW of Isabela, Puerto Rico
  11. 1.7 8 km S of Villalba, Puerto Rico
  12. 1.7 2 km NNE of Santo Domingo, Puerto Rico
  13. 2.7 4 km ESE of Florida, Puerto Rico
  14. 2.2 11 km N of Arecibo, Puerto Rico
  15. 2.5 3 km NW of Las Marias, 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.