QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9Md

Earthquake near Río Blanco, PR

No earthquake was likely felt in Río Blanco in the 24 hours to 5:29 pm AST (21:29 UTC). The last one was M 4.1, 56 km (35 mi) ESE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Río Blanco

This page: a magnitude 1.9 earthquake was recorded in Río Blanco, PR, at 3:50 am AST on 12 November 2016 (07:50 UTC), 38 km deep.

USGS: 1 km NE of Río Blanco, Puerto Rico

36 km (22 mi) ESE of San Juan, PR · 27 km (17 mi) E of Caguas, PR

3:50 am AST, Nov 12, 2016 · · 38 km deep · released about 21 lb of TNT

Every earthquake near Río Blanco Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Naguabo Municipio 5 kmHumacao Municipio 10 kmLas Piedras Municipio 11 kmJuncos Municipio 14 kmCanóvanas Municipio 16 kmRío Grande Municipio 17 kmCeiba Municipio 17 kmLuquillo Municipio 17 kmYabucoa Municipio 20 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
3:50 am AST on 12 November 2016 ()
Where
in Río Blanco, PR · earthquakes near Río Blanco
Magnitude
M 1.9 (Md)
Depth
38 km below the surface
Felt
no reports yet
Nearest
Naguabo Municipio, 5 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3651 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. 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: Duque, Peña Pobre, Naguabo, Antón Ruiz, Punta Santiago, Bajandas.

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 4.3 on 2016-09-02 — about 4,000 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 · 38 km W 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 18.2264, -65.7807. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Naguabo Municipio, PR 5 km (3 mi) ESE earthquakes near Naguabo Municipio
Humacao Municipio, PR 10 km (6 mi) S earthquakes near Humacao Municipio
Las Piedras Municipio, PR 11 km (7 mi) WSW earthquakes near Las Piedras Municipio
Juncos Municipio, PR 14 km (8 mi) W earthquakes near Juncos Municipio
Canóvanas Municipio, PR 16 km (10 mi) NW earthquakes near Canóvanas Municipio
Río Grande Municipio, PR 17 km (10 mi) N earthquakes near Río Grande Municipio

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

Aftershocks so far

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

  1. 2.4 11 km S of Emajagua, Puerto Rico
  2. 2.1 10 km S of Emajagua, Puerto Rico
  3. 2.2 9 km N of Loíza, Puerto Rico
  4. 1.5 9 km S of Emajagua, Puerto Rico
  5. 1.8 6 km SE of Lamboglia, Puerto Rico
  6. 2.2 7 km SSW of Emajagua, Puerto Rico
  7. 2.1 11 km S of Emajagua, Puerto Rico
  8. 1.9 9 km S of Emajagua, Puerto Rico
  9. 2.5 9 km S of Emajagua, Puerto Rico
  10. 2.3 11 km S of Emajagua, Puerto Rico
  11. 2.3 11 km S of Emajagua, Puerto Rico
  12. 1.8 12 km S of Emajagua, Puerto Rico
  13. 2.4 11 km S of Emajagua, Puerto Rico
  14. 2.0 10 km S of Emajagua, Puerto Rico
  15. 4.6 9 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.