QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9Md

Earthquake near El Negro, PR

No earthquake was likely felt in El Negro in the 24 hours to 10:14 am AST (14:14 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 1.9 earthquake was recorded 30 km (19 mi) southeast of El Negro, PR, at 3:16 am AST on 29 December 2016 (07:16 UTC), 8.0 km deep.

USGS: 29 km SE of El Negro, Puerto Rico

75 km (47 mi) SE of San Juan, PR · 59 km (37 mi) SE of Caguas, PR

3:16 am AST, Dec 29, 2016 · · 8.0 km deep · released about 21 lb of TNT

Every earthquake near El Negro Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Maunabo Municipio 31 kmYabucoa Municipio 32 kmHumacao Municipio 34 kmVieques Municipio 36 kmPatillas Municipio 40 kmNaguabo Municipio 40 kmCeiba Municipio 44 kmLas Piedras Municipio 44 kmArroyo Municipio 45 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
3:16 am AST on 29 December 2016 ()
Where
30 km (19 mi) southeast of El Negro, PR · earthquakes near El Negro
Magnitude
M 1.9 (Md)
Depth
8.0 km below the surface
Felt
no reports yet
Nearest
Maunabo Municipio, 31 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3604 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In El Negro, 30 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 21 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 710,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 500,000× the energy of this one
  3. Around the size people start to feel M 3.0 45× the energy of this one
  4. This earthquake M 1.9 about 21 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 4.6 on 2016-12-05 — about 11,000 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 17.8621, -65.6371. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Maunabo Municipio, PR 31 km (20 mi) WNW earthquakes near Maunabo Municipio
Yabucoa Municipio, PR 32 km (20 mi) NW earthquakes near Yabucoa Municipio
Humacao Municipio, PR 34 km (21 mi) NNW earthquakes near Humacao Municipio
Vieques Municipio, PR 36 km (23 mi) NE earthquakes near Vieques Municipio
Patillas Municipio, PR 40 km (25 mi) WNW earthquakes near Patillas Municipio
Naguabo Municipio, PR 40 km (25 mi) NNW earthquakes near Naguabo Municipio

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

Aftershocks so far

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

  1. 2.3 10 km SSE of Emajagua, Puerto Rico
  2. 3.0 18 km SSE of Lamboglia, Puerto Rico
  3. 1.8 9 km SSE of Esperanza, Puerto Rico
  4. 2.4 29 km SE of El Negro, Puerto Rico
  5. 2.2 29 km SE of El Negro, Puerto Rico
  6. 2.5 13 km ESE of Esperanza, Puerto Rico
  7. 1.9 4 km SSE of Esperanza, Puerto Rico
  8. 2.5 0 km SW of Aguas Claras, Puerto Rico
  9. 2.5 Puerto Rico region
  10. 2.6 33 km SE of Emajagua, Puerto Rico
  11. 2.7 29 km SE of El Negro, Puerto Rico
  12. 1.6 3 km SE of Punta Santiago, Puerto Rico
  13. 2.5 31 km SSW of Esperanza, Puerto Rico
  14. 1.8 8 km SSW of Emajagua, Puerto Rico
  15. 2.2 10 km S of Emajagua, 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.