QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6md

Earthquake near Fajardo, PR

No earthquake was likely felt in Fajardo in the 24 hours to 11:39 pm AST (03:39 UTC). The last one was M 4.1, 53 km (33 mi) SE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Fajardo

This page: a magnitude 2.6 earthquake was recorded 43 km (27 mi) north-northeast of Fajardo, PR, at 10:20 pm AST on 8 August 2018 (02:20 UTC), 63 km deep.

USGS: 41 km NNE of Luquillo, Puerto Rico

66 km (41 mi) ENE of San Juan, PR · 58 km (36 mi) ENE of Carolina, PR

10:20 pm AST, Aug 8, 2018 · · 63 km deep · released about 220 lb of TNT

10 km30 km60 km120 km N Fajardo Municipio 35 kmLuquillo Municipio 42 kmRío Grande Municipio 46 kmCulebra Municipio 46 kmCeiba Municipio 50 kmLoíza Municipio 53 kmCanóvanas Municipio 56 kmCarolina Municipio 58 kmNaguabo Municipio 59 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
10:20 pm AST on 8 August 2018 ()
Where
43 km (27 mi) north-northeast of Fajardo, PR · earthquakes near Fajardo
Magnitude
M 2.6 (md)
Depth
63 km below the surface
Felt
no reports yet
Nearest
Fajardo Municipio, 35 km SSW
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 Fajardo, 43 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 220 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 70,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 50,000× the energy of this one
  3. Around the size people start to feel M 3.0 4.4× the energy of this one
  4. This earthquake M 2.6 about 220 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 4.3 on 2016-09-04 — about 390 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.0 73 km NNE of Vieques, Puerto Rico · 34 km N 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 18.6945, -65.5168. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fajardo Municipio, PR 35 km (22 mi) SSW earthquakes near Fajardo Municipio
Luquillo Municipio, PR 42 km (26 mi) SSW earthquakes near Luquillo Municipio
Río Grande Municipio, PR 46 km (29 mi) SW earthquakes near Río Grande Municipio
Culebra Municipio, PR 46 km (29 mi) SSE earthquakes near Culebra Municipio
Ceiba Municipio, PR 50 km (31 mi) SSW earthquakes near Ceiba Municipio
Loíza Municipio, PR 53 km (33 mi) WSW earthquakes near Loíza Municipio

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

Aftershocks so far

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

  1. 2.3 61 km NNW of Charlotte Amalie, U.S. Virgin Islands
  2. 3.2 52 km NNW of Charlotte Amalie, U.S. Virgin Islands
  3. 2.9 61 km N of Culebra, Puerto Rico
  4. 2.4 63 km NNW of Charlotte Amalie, U.S. Virgin Islands
  5. 3.2 65 km NNW of Charlotte Amalie, U.S. Virgin Islands
  6. 2.7 52 km NNW of Charlotte Amalie, U.S. Virgin Islands
  7. 2.7 59 km NNW of Charlotte Amalie, U.S. Virgin Islands
  8. 2.9 55 km NNW of Charlotte Amalie, U.S. Virgin Islands
  9. 3.6 62 km NNE of Culebra, Puerto Rico
  10. 3.1 63 km N of Culebra, Puerto Rico
  11. 3.0 55 km N of Culebra, Puerto Rico
  12. 2.8 60 km NNW of Charlotte Amalie, U.S. Virgin Islands
  13. 2.2 67 km N of Culebra, Puerto Rico
  14. 2.6 Puerto Rico region
  15. 3.1 63 km NNW of Charlotte Amalie, U.S. Virgin Islands

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.