QuakeIndex

Earthquake · reviewed by a seismologist

M 4.3Ml

Earthquake near El Negro, PR

No earthquake was likely felt in El Negro in the 24 hours to 4:13 pm AST (20:13 UTC). The last one was M 2.2, 7 km (5 mi) SSE, at 2:59 pm AST on 4 November 2026, estimated intensity II (weak) in town. Every earthquake near El Negro

This page: a magnitude 4.3 earthquake was recorded 27 km (17 mi) southeast of El Negro, PR, at 6:50 pm AST on 2 September 2016 (22:50 UTC), 11 km deep. 29 people have reported feeling it to USGS.

USGS: 27 km ESE of El Negro, Puerto Rico

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

6:50 pm AST, Sep 2, 2016 · · 11 km deep · released about 43 tons of TNT

10 km30 km60 km120 km N Yabucoa Municipio 29 kmMaunabo Municipio 29 kmHumacao Municipio 30 kmVieques Municipio 33 kmNaguabo Municipio 36 kmPatillas Municipio 38 kmCeiba Municipio 39 kmLas Piedras Municipio 40 kmArroyo Municipio 43 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
6:50 pm AST on 2 September 2016 ()
Where
27 km (17 mi) southeast of El Negro, PR · earthquakes near El Negro
Magnitude
M 4.3 (Ml)
Depth
11 km below the surface
Felt
29 reports · strongest reported intensity IV
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Yabucoa Municipio, 29 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3631 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 121 km (75 mi) from the epicentre. In El Negro, 27 km away, the estimate is intensity III (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: Esperanza 28 km, intensity III · Emajagua 28 km, intensity III · Humacao 34 km, intensity III · Isabel Segunda 34 km, intensity III · Aguas Claras 39 km, intensity III · Fajardo 47 km, intensity III · Jagual 48 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 43 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 4,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 180× the energy of this one
  3. Magna, Utah 2020 M 5.7 130× the energy of this one
  4. This earthquake M 4.3 about 43 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 89× 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 (31 mi) since our catalogue begins in 2016. No other earthquake of M4 or more has been recorded this close in that time.

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 17.9020, -65.6384. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Yabucoa Municipio, PR 29 km (18 mi) NW earthquakes near Yabucoa Municipio
Maunabo Municipio, PR 29 km (18 mi) WNW earthquakes near Maunabo Municipio
Humacao Municipio, PR 30 km (19 mi) NNW earthquakes near Humacao Municipio
Vieques Municipio, PR 33 km (21 mi) NE earthquakes near Vieques Municipio
Naguabo Municipio, PR 36 km (22 mi) NNW earthquakes near Naguabo Municipio
Patillas Municipio, PR 38 km (24 mi) WNW earthquakes near Patillas Municipio

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

Aftershocks so far

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

  1. 2.7 30 km SE of El Negro, Puerto Rico
  2. 2.7 27 km SE of El Negro, Puerto Rico
  3. 2.7 27 km SE of El Negro, Puerto Rico
  4. 2.3 29 km SE of El Negro, Puerto Rico
  5. 2.4 28 km SE of El Negro, Puerto Rico
  6. 2.1 13 km SSE of Esperanza, Puerto Rico
  7. 2.2 28 km SE of El Negro, Puerto Rico
  8. 2.7 28 km SE of El Negro, Puerto Rico
  9. 2.8 28 km SE of El Negro, Puerto Rico
  10. 2.1 15 km SE of El Negro, Puerto Rico
  11. 2.6 29 km SE of El Negro, Puerto Rico
  12. 2.3 28 km SE of El Negro, Puerto Rico
  13. 2.1 29 km SE of El Negro, Puerto Rico
  14. 2.1 28 km SE of El Negro, Puerto Rico
  15. 2.3 27 km SE 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.