QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

50 km N of Arecibo, Puerto Rico

Yes. A magnitude 2.8 earthquake was recorded 50 km N of Arecibo, Puerto Rico, 83 km (51 mi) NW of San Juan, PR, at 9:15 pm AST on 23 October 2019 (01:15 UTC), 58 km deep.

83 km (51 mi) NW of San Juan, PR · 53 km (33 mi) NNE of Arecibo, PR

· 58 km deep · released about 460 lb of TNT

10 km30 km60 km120 km N Barceloneta Municipio 51 kmArecibo Municipio 54 kmManatí Municipio 55 kmHatillo Municipio 56 kmVega Baja Municipio 57 kmCamuy Municipio 58 kmQuebradillas Municipio 60 kmFlorida Municipio 62 kmVega Alta Municipio 62 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 2.8 (md)
Depth
58 km below the surface
Felt
no reports yet
Nearest
Barceloneta Municipio, 51 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2576 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. 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 460 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 33,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 23,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.1× the energy of this one
  4. This earthquake M 2.8 about 460 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 4.8 on 2017-08-18 — about 1,000 times the energy of this one.

Before 2016, the USGS record lists 11 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 61 km N of Hatillo, Puerto Rico · 23 km NW of this epicentre
  2. 6.0 81 km N of Isabela, Puerto Rico · 46 km NW of this epicentre
  3. 5.9 78 km N of Arecibo, Puerto Rico · 28 km N of this epicentre
  4. 5.8 12 km N of Garrochales, Puerto Rico · 40 km S of this epicentre
  5. 5.7 78 km N of Tierras Nuevas Poniente, Puerto Rico · 28 km NNE 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 18.9216, -66.6273. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Barceloneta Municipio, PR 51 km (32 mi) S earthquakes near Barceloneta Municipio
Arecibo Municipio, PR 54 km (34 mi) S earthquakes near Arecibo Municipio
Manatí Municipio, PR 55 km (34 mi) SSE earthquakes near Manatí Municipio
Hatillo Municipio, PR 56 km (35 mi) SSW earthquakes near Hatillo Municipio
Vega Baja Municipio, PR 57 km (36 mi) SSE earthquakes near Vega Baja Municipio
Camuy Municipio, PR 58 km (36 mi) SSW earthquakes near Camuy Municipio

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

Aftershocks so far

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

  1. 2.4 21 km NNW of Camuy, Puerto Rico
  2. 2.2 62 km N of Hatillo, Puerto Rico
  3. 2.4 37 km N of Isabela, Puerto Rico
  4. 2.2 67 km N of Brenas, Puerto Rico
  5. 2.3 35 km N of Hatillo, Puerto Rico
  6. 2.1 71 km N of Tierras Nuevas Poniente, Puerto Rico
  7. 2.1 17 km N of Camuy, Puerto Rico
  8. 1.8 63 km N of Tierras Nuevas Poniente, Puerto Rico
  9. 1.8 47 km N of Brenas, Puerto Rico
  10. 2.0 70 km N of Tierras Nuevas Poniente, Puerto Rico
  11. 2.1 72 km N of Tierras Nuevas Poniente, Puerto Rico
  12. 3.3 66 km N of Tierras Nuevas Poniente, Puerto Rico
  13. 3.1 64 km N of Tierras Nuevas Poniente, Puerto Rico
  14. 2.6 87 km N of Isabela, Puerto Rico
  15. 2.7 64 km N of Isabela, 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.