QuakeIndex

Earthquake · reviewed by a seismologist

M 3.8Md

Earthquake near Luis M. Cintron, PR

No earthquake was likely felt in Luis M. Cintron in the 24 hours to 4:32 am AST (08:32 UTC). The last one was M 4.1, 50 km (31 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 Luis M. Cintron

This page: a magnitude 3.8 earthquake was recorded 15 km (9 mi) east of Luis M. Cintron, PR, at 9:42 am AST on 17 October 2016 (13:42 UTC), 122 km deep. 15 people have reported feeling it to USGS.

USGS: 14 km E of Luis M. Cintron, Puerto Rico

61 km (38 mi) E of San Juan, PR · 52 km (32 mi) ESE of Carolina, PR

9:42 am AST, Oct 17, 2016 · · 122 km deep · released about 7.6 tons of TNT

Every earthquake near Luis M. Cintron Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Fajardo Municipio 13 kmCeiba Municipio 14 kmCulebra Municipio 20 kmVieques Municipio 22 kmLuquillo Municipio 23 kmNaguabo Municipio 27 kmRío Grande Municipio 33 kmHumacao Municipio 36 kmCanóvanas Municipio 41 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
9:42 am AST on 17 October 2016 ()
Where
15 km (9 mi) east of Luis M. Cintron, PR · earthquakes near Luis M. Cintron
Magnitude
M 3.8 (Md)
Depth
122 km below the surface
Felt
15 reports · strongest reported intensity II
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Fajardo Municipio, 13 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3587 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 Luis M. Cintron, 15 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.

Earthquakes near other towns within 30 km: Fajardo, Aguas Claras, Isabel Segunda, Culebra, Daguao, Ramos.

How big was it?

This earthquake released about 7.6 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.8 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 22,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 710× the energy of this one
  4. This earthquake M 3.8 about 7.6 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 16× more

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 2016-09-02 — about 5.6 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 18.3096, -65.4978. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fajardo Municipio, PR 13 km (8 mi) NW earthquakes near Fajardo Municipio
Ceiba Municipio, PR 14 km (9 mi) WSW earthquakes near Ceiba Municipio
Culebra Municipio, PR 20 km (13 mi) E earthquakes near Culebra Municipio
Vieques Municipio, PR 22 km (13 mi) SSE earthquakes near Vieques Municipio
Luquillo Municipio, PR 23 km (14 mi) WNW earthquakes near Luquillo Municipio
Naguabo Municipio, PR 27 km (17 mi) WSW earthquakes near Naguabo Municipio

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

Aftershocks so far

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

  1. 2.0 27 km SE of El Negro, Puerto Rico
  2. 2.0 27 km SW of Esperanza, Puerto Rico
  3. 2.1 26 km SW of Esperanza, Puerto Rico
  4. 2.7 27 km SSW of Esperanza, Puerto Rico
  5. 2.8 24 km SW of Esperanza, Puerto Rico
  6. 1.9 21 km SW of Esperanza, Puerto Rico
  7. 2.9 24 km SW of Esperanza, Puerto Rico
  8. 2.9 23 km SW of Esperanza, Puerto Rico
  9. 1.9 27 km SW of Esperanza, Puerto Rico
  10. 2.5 26 km SW of Esperanza, Puerto Rico
  11. 2.2 28 km SE of El Negro, Puerto Rico
  12. 3.0 25 km SW of Esperanza, Puerto Rico
  13. 1.8 2 km N of Vieques, Puerto Rico
  14. 2.9 23 km SW of Esperanza, Puerto Rico
  15. 1.6 11 km E of El Negro, 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.