QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Sabana Grande, PR

Yes: an earthquake was likely felt in Sabana Grande in the last 24 hours. M 2.4, 16 km (10 mi) SSE of Sabana Grande, at 3:43 pm AST on 11 November 2026 (19:43 UTC); the estimated shaking in Sabana Grande was intensity II (weak). Every earthquake near Sabana Grande

This page: a magnitude 1.6 earthquake was recorded 12 km (8 mi) northeast of Sabana Grande, PR, at 3:50 am AST on 9 October 2018 (07:50 UTC), 8.0 km deep.

USGS: 12 km NE of Sabana Grande, Puerto Rico

30 km (19 mi) WNW of Ponce, PR · 29 km (18 mi) ESE of Mayagüez, PR

3:50 am AST, Oct 9, 2018 · · 8.0 km deep · released about 7.6 lb of TNT

Every earthquake near Sabana Grande Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Yauco Municipio 7 kmMaricao Municipio 8 kmSabana Grande Municipio 11 kmAdjuntas Municipio 12 kmLas Marías Municipio 15 kmLares Municipio 15 kmGuayanilla Municipio 17 kmSan Germán Municipio 18 kmPeñuelas 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 9 October 2018 ()
Where
12 km (8 mi) northeast of Sabana Grande, PR · earthquakes near Sabana Grande
Magnitude
M 1.6 (md)
Depth
8.0 km below the surface
Felt
no reports yet
Nearest
Yauco Municipio, 7 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2956 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 8 km (5 mi) from the epicentre. In Sabana Grande, 12 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: Yauco, Lluveras, Maricao, Liborio Negron Torres, Palomas, Santo Domingo.

How big was it?

This earthquake released about 7.6 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 2,000,000× 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 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.6 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 6.3 6 km WNW of Aguadilla, Puerto Rico · 49 km NW of this epicentre
  2. 5.8 4 km E of Moca, Puerto Rico · 36 km NW 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 18.1435, -66.8693. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Yauco Municipio, PR 7 km (4 mi) S earthquakes near Yauco Municipio
Maricao Municipio, PR 8 km (5 mi) WNW earthquakes near Maricao Municipio
Sabana Grande Municipio, PR 11 km (7 mi) SW earthquakes near Sabana Grande Municipio
Adjuntas Municipio, PR 12 km (8 mi) ENE earthquakes near Adjuntas Municipio
Las Marías Municipio, PR 15 km (9 mi) NW earthquakes near Las Marías Municipio
Lares Municipio, PR 15 km (9 mi) N earthquakes near Lares 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. 2.0 8 km NW of Puerto Real, Puerto Rico
  2. 2.2 8 km NW of Puerto Real, Puerto Rico
  3. 1.9 6 km NW of Puerto Real, Puerto Rico
  4. 2.1 6 km NNW of Puerto Real, Puerto Rico
  5. 1.7 5 km NW of Puerto Real, Puerto Rico
  6. 1.9 11 km W of Mayagüez, Puerto Rico
  7. 1.7 1 km NNE of Sabana Grande, Puerto Rico
  8. 2.0 8 km WNW of Puerto Real, Puerto Rico
  9. 1.9 4 km N of Puerto Real, Puerto Rico
  10. 2.3 7 km WNW of Puerto Real, Puerto Rico
  11. 1.8 4 km W of Palmarejo, Puerto Rico
  12. 2.4 8 km NW of Puerto Real, Puerto Rico
  13. 1.9 7 km NW of Puerto Real, Puerto Rico
  14. 1.7 9 km NW of Puerto Real, Puerto Rico
  15. 1.7 7 km NW of Puerto Real, 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.