QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

50 km N of Hatillo, Puerto Rico

Yes. A magnitude 2.1 earthquake was recorded 50 km N of Hatillo, Puerto Rico, 56 km (35 mi) NNW of Arecibo, PR, at 2:09 am AST on 27 March 2018 (06:09 UTC), 28 km deep.

56 km (35 mi) NNW of Arecibo, PR · 103 km (64 mi) NW of San Juan, PR

· 28 km deep · released about 51 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Quebradillas Municipio 54 kmIsabela Municipio 54 kmCamuy Municipio 56 kmHatillo Municipio 56 kmAguadilla Municipio 60 kmArecibo Municipio 60 kmBarceloneta Municipio 62 kmMoca Municipio 67 kmManatí Municipio 68 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
Magnitude
M 2.1 (md)
Depth
28 km below the surface
Felt
no reports yet
Nearest
Quebradillas Municipio, 54 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3153 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.

How big was it?

This earthquake released about 51 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 210,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 51 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 4.7 on 2017-07-17 — about 5,800 times the energy of this one.

Before 2016, the USGS record lists 17 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.7 45 km N of San Antonio, Puerto Rico · 27 km W of this epicentre
  2. 7.1 24 km NNW of San Antonio, Puerto Rico · 44 km SW of this epicentre
  3. 6.4 61 km N of Hatillo, Puerto Rico · 12 km NNE of this epicentre
  4. 6.1 18 km NNW of San Antonio, Puerto Rico · 48 km SW of this epicentre
  5. 6.0 81 km N of Isabela, Puerto Rico · 32 km NNW 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 18.9451, -66.8598. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Quebradillas Municipio, PR 54 km (33 mi) S earthquakes near Quebradillas Municipio
Isabela Municipio, PR 54 km (33 mi) SSW earthquakes near Isabela Municipio
Camuy Municipio, PR 56 km (35 mi) S earthquakes near Camuy Municipio
Hatillo Municipio, PR 56 km (35 mi) S earthquakes near Hatillo Municipio
Aguadilla Municipio, PR 60 km (37 mi) SSW earthquakes near Aguadilla Municipio
Arecibo Municipio, PR 60 km (37 mi) SSE earthquakes near Arecibo Municipio

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

Aftershocks so far

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

  1. 3.2 Puerto Rico region
  2. 3.1 Mona Passage
  3. 2.5 25 km N of Tierras Nuevas Poniente, Puerto Rico
  4. 2.9 48 km N of Hatillo, Puerto Rico
  5. 2.7 56 km N of Hatillo, Puerto Rico
  6. 3.2 80 km N of San Antonio, Puerto Rico
  7. 3.2 38 km NNW of San Antonio, Puerto Rico
  8. 2.8 12 km N of Quebradillas, Puerto Rico
  9. 2.9 12 km NNE of Isabela, Puerto Rico
  10. 2.8 16 km NNE of Carrizales, Puerto Rico
  11. 2.6 28 km NNW of Tierras Nuevas Poniente, Puerto Rico
  12. 1.9 23 km NNE of Arecibo, Puerto Rico
  13. 2.4 20 km N of Hatillo, Puerto Rico
  14. 2.8 34 km NNW of San Antonio, Puerto Rico
  15. 2.8 27 km N of Arecibo, 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.