QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

Earthquake near Arecibo, PR

No earthquake was likely felt in Arecibo in the 24 hours to 5:49 pm AST (21:49 UTC). The last one was M 3.4, 49 km (31 mi) NW, at 9:00 pm AST on 27 October 2026, estimated intensity II (weak) in town. Every earthquake near Arecibo

This page: a magnitude 2.8 earthquake was recorded 45 km (28 mi) north-northwest of Arecibo, PR, at 9:33 am AST on 24 September 2019 (13:33 UTC), 18 km deep.

USGS: 41 km N of Hatillo, Puerto Rico

95 km (59 mi) WNW of San Juan, PR · 46 km (29 mi) NNW of Arecibo, PR

9:33 am AST, Sep 24, 2019 · · 18 km deep · released about 490 lb of TNT

Every earthquake near Arecibo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Quebradillas Municipio 46 kmCamuy Municipio 47 kmIsabela Municipio 47 kmHatillo Municipio 47 kmArecibo Municipio 50 kmBarceloneta Municipio 52 kmAguadilla Municipio 54 kmManatí Municipio 58 kmMoca Municipio 60 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
9:33 am AST on 24 September 2019 ()
Where
45 km (28 mi) north-northwest of Arecibo, PR · earthquakes near Arecibo
Magnitude
M 2.8 (md)
Depth
18 km below the surface
Felt
no reports yet
Nearest
Quebradillas Municipio, 46 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2602 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 21 km (13 mi) from the epicentre. In Arecibo, 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.

How big was it?

This earthquake released about 490 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 31,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.9× the energy of this one
  4. This earthquake M 2.8 about 490 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 5.1 on 2019-09-24 — about 2,400 times the energy of this one.

Before 2016, the USGS record lists 16 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.7 45 km N of San Antonio, Puerto Rico · 31 km W of this epicentre
  2. 7.1 24 km NNW of San Antonio, Puerto Rico · 43 km WSW of this epicentre
  3. 6.4 61 km N of Hatillo, Puerto Rico · 20 km N of this epicentre
  4. 6.1 18 km NNW of San Antonio, Puerto Rico · 45 km SW of this epicentre
  5. 6.0 81 km N of Isabela, Puerto Rico · 42 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 18.8643, -66.8233. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Quebradillas Municipio, PR 46 km (28 mi) SSW earthquakes near Quebradillas Municipio
Camuy Municipio, PR 47 km (29 mi) S earthquakes near Camuy Municipio
Isabela Municipio, PR 47 km (29 mi) SSW earthquakes near Isabela Municipio
Hatillo Municipio, PR 47 km (29 mi) S earthquakes near Hatillo Municipio
Arecibo Municipio, PR 50 km (31 mi) SSE earthquakes near Arecibo Municipio
Barceloneta Municipio, PR 52 km (32 mi) SSE earthquakes near Barceloneta Municipio

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

Aftershocks so far

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

  1. 2.4 31 km NNW of San Antonio, Puerto Rico
  2. 2.9 65 km N of San Antonio, Puerto Rico
  3. 2.9 28 km N of Isabela, Puerto Rico
  4. 2.8 59 km N of San Antonio, Puerto Rico
  5. 2.8 66 km NNW of San Antonio, Puerto Rico
  6. 2.8 58 km N of San Antonio, Puerto Rico
  7. 2.9 57 km N of San Antonio, Puerto Rico
  8. 2.9 58 km N of Isabela, Puerto Rico
  9. 4.4 61 km N of San Antonio, Puerto Rico
  10. 2.7 56 km N of San Antonio, Puerto Rico
  11. 2.6 61 km N of San Antonio, Puerto Rico
  12. 2.4 59 km N of San Antonio, Puerto Rico
  13. 4.8 66 km N of San Antonio, Puerto Rico
  14. 2.4 66 km N of Tierras Nuevas Poniente, Puerto Rico
  15. 3.4 74 km N of Tierras Nuevas Poniente, 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.