QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

Earthquake near Naranjito, PR

No earthquake was likely felt in Naranjito in the 24 hours to 12:51 am AST (04:51 UTC). The last one was M 4.8, 84 km (52 mi) WSW, at 9:19 am AST on 18 September 2026, estimated intensity III (weak) in town; 86 felt reports to USGS. Every earthquake near Naranjito

This page: a magnitude 2.8 earthquake was recorded 3 km (2 mi) north-northeast of Naranjito, PR, at 11:33 am AST on 8 August 2018 (15:33 UTC), 114 km deep.

USGS: 3 km NNE of Naranjito, Puerto Rico

9 km (6 mi) SW of Bayamón, PR

11:33 am AST, Aug 8, 2018 · · 114 km deep · released about 550 lb of TNT

Every earthquake near Naranjito Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Toa Alta Municipio 4 kmNaranjito Municipio 5 kmBayamón Municipio 7 kmCorozal Municipio 10 kmComerío Municipio 12 kmGuaynabo Municipio 13 kmAguas Buenas Municipio 14 kmToa Baja Municipio 15 kmCataño Municipio 16 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
11:33 am AST on 8 August 2018 ()
Where
3 km (2 mi) north-northeast of Naranjito, PR · earthquakes near Naranjito
Magnitude
M 2.8 (md)
Depth
114 km below the surface
Felt
no reports yet
Nearest
Toa Alta Municipio, 4 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2947 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. In Naranjito, 3 km away, the estimate is intensity I (not felt). 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: Galateo, H. Rivera Colon, Pájaros, Toa Alta, Mucarabones, San José.

How big was it?

This earthquake released about 550 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 28,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 19,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.7× the energy of this one
  4. This earthquake M 2.8 about 550 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 3 earthquakes of M5 or more within 50 km:

  1. 5.8 12 km N of Garrochales, Puerto Rico · 43 km NW of this epicentre
  2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 13 km SE of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 22 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 18.3303, -66.2361. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Toa Alta Municipio, PR 4 km (2 mi) NNW earthquakes near Toa Alta Municipio
Naranjito Municipio, PR 5 km (3 mi) SSW earthquakes near Naranjito Municipio
Bayamón Municipio, PR 7 km (5 mi) ENE earthquakes near Bayamón Municipio
Corozal Municipio, PR 10 km (6 mi) WSW earthquakes near Corozal Municipio
Comerío Municipio, PR 12 km (7 mi) S earthquakes near Comerío Municipio
Guaynabo Municipio, PR 13 km (8 mi) E earthquakes near Guaynabo Municipio

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

Aftershocks so far

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

  1. 2.2 17 km NNW of Garrochales, Puerto Rico
  2. 2.7 5 km ESE of San Juan, Puerto Rico
  3. 2.0 0 km NW of Playita Cortada, Puerto Rico
  4. 2.2 1 km ESE of Potala Pastillo, Puerto Rico
  5. 2.1 3 km ESE of Cayey, Puerto Rico
  6. 2.3 17 km NNE of Brenas, Puerto Rico
  7. 2.7 6 km NW of Sabana, Puerto Rico
  8. 2.4 2 km SSE of Cidra, Puerto Rico
  9. 2.5 3 km WSW of Sumidero, Puerto Rico
  10. 1.5 3 km W of Palo Seco, Puerto Rico
  11. 2.5 8 km NNE of Brenas, Puerto Rico
  12. 2.4 18 km NNW of Brenas, Puerto Rico
  13. 2.1 0 km NE of Ciales, Puerto Rico
  14. 2.2 2 km ESE of Parcelas Nuevas, Puerto Rico
  15. 2.3 1 km WSW of Campo Rico, 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.