QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5md

Earthquake near El Negro, PR

Yes: an earthquake was likely felt in El Negro in the last 24 hours. M 2.9, 24 km (15 mi) SSE of El Negro, at 5:20 pm AST on 11 November 2026 (21:20 UTC); the estimated shaking in El Negro was intensity II (weak). 1 person has reported feeling it to USGS. Every earthquake near El Negro

This page: a magnitude 3.5 earthquake was recorded 27 km (17 mi) southeast of El Negro, PR, at 2:35 pm AST on 5 September 2016 (18:35 UTC), 6.7 km deep. 11 people have reported feeling it to USGS.

USGS: 26 km SE of El Negro, Puerto Rico

72 km (45 mi) SE of San Juan, PR · 56 km (35 mi) SE of Caguas, PR

2:35 pm AST, Sep 5, 2016 · · 6.7 km deep · released about 2.7 tons of TNT

Every earthquake near El Negro Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Maunabo Municipio 29 kmYabucoa Municipio 29 kmHumacao Municipio 31 kmVieques Municipio 35 kmNaguabo Municipio 37 kmPatillas Municipio 38 kmLas Piedras Municipio 41 kmCeiba Municipio 41 kmArroyo Municipio 42 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
2:35 pm AST on 5 September 2016 ()
Where
27 km (17 mi) southeast of El Negro, PR · earthquakes near El Negro
Magnitude
M 3.5 (md)
Depth
6.7 km below the surface
Felt
11 reports · strongest reported intensity III
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Maunabo Municipio, 29 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3631 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 63 km (39 mi) from the epicentre. In El Negro, 27 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.

Likely felt in: Emajagua 27 km, intensity II · Esperanza 30 km, intensity II · Humacao 35 km, intensity II · Isabel Segunda 37 km, intensity II · Aguas Claras 41 km, intensity II · Jagual 47 km, intensity II · Fajardo 49 km, intensity II · Guayama 50 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 2.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 63,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,000× the energy of this one
  4. This earthquake M 3.5 about 2.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 5.6× 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 16 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 17.8850, -65.6532. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Maunabo Municipio, PR 29 km (18 mi) WNW earthquakes near Maunabo Municipio
Yabucoa Municipio, PR 29 km (18 mi) NW earthquakes near Yabucoa Municipio
Humacao Municipio, PR 31 km (19 mi) NNW earthquakes near Humacao Municipio
Vieques Municipio, PR 35 km (22 mi) NE earthquakes near Vieques Municipio
Naguabo Municipio, PR 37 km (23 mi) NNW earthquakes near Naguabo Municipio
Patillas Municipio, PR 38 km (23 mi) WNW earthquakes near Patillas Municipio

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

Aftershocks so far

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

  1. 1.7 14 km SSE of Esperanza, Puerto Rico
  2. 2.6 27 km SW of Esperanza, Puerto Rico
  3. 2.4 11 km SSE of Lamboglia, Puerto Rico
  4. 2.1 27 km SSW of Esperanza, Puerto Rico
  5. 2.0 2 km NE of Jagual, Puerto Rico
  6. 2.5 14 km SE of Esperanza, Puerto Rico
  7. 1.7 29 km SE of El Negro, Puerto Rico
  8. 2.1 8 km ESE of El Negro, Puerto Rico
  9. 2.4 21 km S of Esperanza, Puerto Rico
  10. 2.3 30 km SE of Emajagua, Puerto Rico
  11. 2.6 29 km SE of El Negro, Puerto Rico
  12. 2.4 22 km SSE of Esperanza, Puerto Rico
  13. 2.2 11 km SE of Esperanza, Puerto Rico
  14. 2.6 26 km SE of El Negro, Puerto Rico
  15. 2.3 15 km SE of Esperanza, 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.