QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Monte Grande, PR

Yes: an earthquake was likely felt in Monte Grande in the last 24 hours. M 2.2, 14 km (9 mi) SSE of Monte Grande, at 2:59 pm AST on 13 November 2026 (18:59 UTC); the estimated shaking in Monte Grande was intensity II (weak). Every earthquake near Monte Grande

This page: a magnitude 1.6 earthquake was recorded 3 km (2 mi) north-northwest of Monte Grande, PR, at 2:59 am AST on 11 November 2018 (06:59 UTC), 20 km deep.

USGS: 2 km NNW of Monte Grande, Puerto Rico

10 km (6 mi) SSE of Mayagüez, PR · 116 km (72 mi) WSW of San Juan, PR

2:59 am AST, Nov 11, 2018 · · 20 km deep · released about 7.8 lb of TNT

Every earthquake near Monte Grande Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Hormigueros Municipio 3 kmSan Germán Municipio 8 kmCabo Rojo Municipio 14 kmLajas Municipio 17 kmSabana Grande Municipio 18 kmAñasco Municipio 20 kmLas Marías Municipio 20 kmMaricao Municipio 20 kmGuánica Municipio 27 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
2:59 am AST on 11 November 2018 ()
Where
3 km (2 mi) north-northwest of Monte Grande, PR · earthquakes near Monte Grande
Magnitude
M 1.6 (md)
Depth
20 km below the surface
Felt
no reports yet
Nearest
Hormigueros Municipio, 3 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2925 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 Monte Grande, 3 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: Hormigueros, Cabo Rojo, Sabana Eneas, San Germán, Puerto Real, Palmarejo.

How big was it?

This earthquake released about 7.8 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 120× the energy of this one
  4. This earthquake M 1.6 about 7.8 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 2017-10-14 — about 11,000 times the energy of this one.

Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:

  1. 6.3 6 km WNW of Aguadilla, Puerto Rico · 38 km NNW of this epicentre
  2. 5.8 4 km E of Moca, Puerto Rico · 33 km N of this epicentre
  3. 5.2 19 km SW of Stella, Puerto Rico · 28 km WNW of this epicentre
  4. 5.1 21 km SW of Stella, Puerto Rico · 28 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 18.1108, -67.1175. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Hormigueros Municipio, PR 3 km (2 mi) N earthquakes near Hormigueros Municipio
San Germán Municipio, PR 8 km (5 mi) E earthquakes near San Germán Municipio
Cabo Rojo Municipio, PR 14 km (9 mi) SSW earthquakes near Cabo Rojo Municipio
Lajas Municipio, PR 17 km (10 mi) SSE earthquakes near Lajas Municipio
Sabana Grande Municipio, PR 18 km (11 mi) E earthquakes near Sabana Grande Municipio
Añasco Municipio, PR 20 km (12 mi) N earthquakes near Añasco 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. 1.8 23 km S of La Parguera, Puerto Rico
  2. 1.8 9 km S of Guánica, Puerto Rico
  3. 2.7 27 km WNW of Puerto Real, Puerto Rico
  4. 1.7 3 km NNW of Sabana Grande, Puerto Rico
  5. 2.1 0 km SSW of Mayagüez, Puerto Rico
  6. 2.1 2 km SSE of Hormigueros, Puerto Rico
  7. 1.7 5 km E of Lajas, Puerto Rico
  8. 1.9 9 km NNE of Lluveras, Puerto Rico
  9. 1.8 3 km WNW of Mayagüez, Puerto Rico
  10. 1.9 19 km S of Guánica, Puerto Rico
  11. 1.7 3 km N of Mayagüez, Puerto Rico
  12. 2.0 8 km NNW of Puerto Real, Puerto Rico
  13. 2.0 11 km NW of Puerto Real, Puerto Rico
  14. 1.8 7 km WNW of Maricao, Puerto Rico
  15. 2.8 7 km SSW of La Playa, 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.