QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Palmarejo, PR

No earthquake was likely felt in Palmarejo in the 24 hours to 11:38 pm AST (03:38 UTC). The last one was M 2.1, 6 km (4 mi) SW, at 11:57 pm AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Palmarejo

This page: a magnitude 1.6 earthquake was recorded 5 km (3 mi) south-southwest of Palmarejo, PR, at 6:40 am AST on 7 August 2018 (10:40 UTC), 13 km deep.

USGS: 4 km SSW of Palmarejo, Puerto Rico

23 km (14 mi) SSE of Mayagüez, PR · 117 km (73 mi) WSW of San Juan, PR

6:40 am AST, Aug 7, 2018 · · 13 km deep · released about 7.1 lb of TNT

Every earthquake near Palmarejo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lajas Municipio 6 kmCabo Rojo Municipio 10 kmSan Germán Municipio 13 kmHormigueros Municipio 15 kmSabana Grande Municipio 18 kmGuánica Municipio 18 kmMaricao Municipio 25 kmYauco Municipio 26 kmLas Marías 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
6:40 am AST on 7 August 2018 ()
Where
5 km (3 mi) south-southwest of Palmarejo, PR · earthquakes near Palmarejo
Magnitude
M 1.6 (md)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Lajas Municipio, 6 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3019 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 Palmarejo, 5 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: La Parguera, Lajas, Boquerón, Sabana Eneas, Monte Grande, San Germán.

How big was it?

This earthquake released about 7.1 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 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× 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 7.1 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 3 earthquakes of M5 or more within 50 km:

  1. 5.8 4 km E of Moca, Puerto Rico · 45 km N of this epicentre
  2. 5.2 19 km SW of Stella, Puerto Rico · 36 km NW of this epicentre
  3. 5.1 21 km SW of Stella, Puerto Rico · 36 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 17.9980, -67.0886. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lajas Municipio, PR 6 km (3 mi) ESE earthquakes near Lajas Municipio
Cabo Rojo Municipio, PR 10 km (6 mi) W earthquakes near Cabo Rojo Municipio
San Germán Municipio, PR 13 km (8 mi) NNE earthquakes near San Germán Municipio
Hormigueros Municipio, PR 15 km (10 mi) N earthquakes near Hormigueros Municipio
Sabana Grande Municipio, PR 18 km (11 mi) ENE earthquakes near Sabana Grande Municipio
Guánica Municipio, PR 18 km (11 mi) ESE earthquakes near Guánica 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. 2.1 Mona Passage
  2. 1.8 3 km NW of Sabana Grande, Puerto Rico
  3. 2.1 3 km WSW of Maricao, Puerto Rico
  4. 2.1 5 km WNW of Maricao, Puerto Rico
  5. 2.6 8 km W of Rincón, Puerto Rico
  6. 1.9 5 km ESE of La Parguera, Puerto Rico
  7. 2.4 20 km WNW of Puerto Real, Puerto Rico
  8. 1.6 2 km SE of Guánica, Puerto Rico
  9. 1.6 5 km SW of Guánica, Puerto Rico
  10. 1.8 6 km SW of Liborio Negron Torres, Puerto Rico
  11. 1.8 8 km SSE of Guánica, Puerto Rico
  12. 1.6 8 km S of La Parguera, Puerto Rico
  13. 1.7 3 km W of Sabana Grande, Puerto Rico
  14. 2.5 14 km SSW of Guánica, Puerto Rico
  15. 2.4 14 km SSW of Guánica, 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.