QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8Md

Earthquake near Comunas, PR

No earthquake was likely felt in Comunas in the 24 hours to 5:17 am AST (09:17 UTC). The last one was M 2.9, 29 km (18 mi) SSE, at 5:20 pm AST on 11 November 2026, estimated intensity II (weak) in town; 1 felt report to USGS. Every earthquake near Comunas

This page: a magnitude 1.8 earthquake was recorded 6 km (4 mi) east-southeast of Comunas, PR, at 3:19 am AST on 18 November 2016 (07:19 UTC), 14 km deep.

USGS: 6 km ESE of Comunas, Puerto Rico

48 km (30 mi) SE of San Juan, PR · 32 km (20 mi) SE of Caguas, PR

3:19 am AST, Nov 18, 2016 · · 14 km deep · released about 15 lb of TNT

Every earthquake near Comunas Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Yabucoa Municipio 7 kmHumacao Municipio 8 kmMaunabo Municipio 13 kmLas Piedras Municipio 16 kmNaguabo Municipio 18 kmSan Lorenzo Municipio 22 kmPatillas Municipio 22 kmJuncos Municipio 22 kmCeiba Municipio 28 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
3:19 am AST on 18 November 2016 ()
Where
6 km (4 mi) east-southeast of Comunas, PR · earthquakes near Comunas
Magnitude
M 1.8 (Md)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Yabucoa Municipio, 7 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3647 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Comunas, 6 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: Candelero Arriba, El Negro, Yabucoa, Humacao, Bajandas, Martorell.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 2016-09-02 — about 5,600 times the energy of this one.

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

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 42 km WNW 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 18.0632, -65.7926. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Yabucoa Municipio, PR 7 km (4 mi) W earthquakes near Yabucoa Municipio
Humacao Municipio, PR 8 km (5 mi) N earthquakes near Humacao Municipio
Maunabo Municipio, PR 13 km (8 mi) WSW earthquakes near Maunabo Municipio
Las Piedras Municipio, PR 16 km (10 mi) NNW earthquakes near Las Piedras Municipio
Naguabo Municipio, PR 18 km (11 mi) NNE earthquakes near Naguabo Municipio
San Lorenzo Municipio, PR 22 km (13 mi) WNW earthquakes near San Lorenzo Municipio

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

Aftershocks so far

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

  1. 2.9 27 km SSW of Esperanza, Puerto Rico
  2. 2.2 8 km S of Emajagua, Puerto Rico
  3. 3.0 7 km N of Vieques, Puerto Rico
  4. 2.7 10 km S of Emajagua, Puerto Rico
  5. 2.8 8 km S of Emajagua, Puerto Rico
  6. 2.7 10 km S of Emajagua, Puerto Rico
  7. 2.1 2 km SE of Esperanza, Puerto Rico
  8. 2.8 25 km SW of Esperanza, Puerto Rico
  9. 2.0 11 km S of Emajagua, Puerto Rico
  10. 2.0 24 km SSW of Esperanza, Puerto Rico
  11. 3.0 10 km S of Emajagua, Puerto Rico
  12. 2.0 8 km S of Emajagua, Puerto Rico
  13. 2.2 10 km S of Emajagua, Puerto Rico
  14. 2.4 11 km S 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.