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 5:53 pm AST (21:53 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 3 km (2 mi) southwest of Palmarejo, PR, at 4:24 am AST on 28 May 2017 (08:24 UTC), 14 km deep.

USGS: 2 km SW of Palmarejo, Puerto Rico

21 km (13 mi) SSE of Mayagüez, PR · 117 km (72 mi) WSW of San Juan, PR

4:24 am AST, May 28, 2017 · · 14 km deep · released about 7.8 lb of TNT

10 km30 km60 km120 km N Lajas Municipio 7 kmCabo Rojo Municipio 10 kmSan Germán Municipio 11 kmHormigueros Municipio 13 kmSabana Grande Municipio 17 kmGuánica Municipio 20 kmMaricao Municipio 24 kmYauco Municipio 26 kmLas Marías Municipio 26 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
4:24 am AST on 28 May 2017 ()
Where
3 km (2 mi) southwest of Palmarejo, PR · earthquakes near Palmarejo
Magnitude
M 1.6 (md)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Lajas Municipio, 7 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3454 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, 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: Lajas, La Parguera, Sabana Eneas, Monte Grande, Boquerón, San Germán.

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

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

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 · 48 km NNW of this epicentre
  2. 5.8 4 km E of Moca, Puerto Rico · 42 km N of this epicentre
  3. 5.2 19 km SW of Stella, Puerto Rico · 35 km WNW of this epicentre
  4. 5.1 21 km SW of Stella, Puerto Rico · 34 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 18.0210, -67.0913. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lajas Municipio, PR 7 km (4 mi) SE earthquakes near Lajas Municipio
Cabo Rojo Municipio, PR 10 km (6 mi) WSW earthquakes near Cabo Rojo Municipio
San Germán Municipio, PR 11 km (7 mi) NNE earthquakes near San Germán Municipio
Hormigueros Municipio, PR 13 km (8 mi) NNW earthquakes near Hormigueros Municipio
Sabana Grande Municipio, PR 17 km (10 mi) ENE earthquakes near Sabana Grande Municipio
Guánica Municipio, PR 20 km (12 mi) ESE earthquakes near Guánica Municipio

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

Aftershocks so far

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

  1. 2.1 9 km ESE of Adjuntas, Puerto Rico
  2. 2.2 4 km S of Magas Arriba, Puerto Rico
  3. 2.1 9 km SSW of Guánica, Puerto Rico
  4. 1.9 12 km SSW of Guánica, Puerto Rico
  5. 2.3 1 km E of Pole Ojea, Puerto Rico
  6. 1.7 3 km SW of Las Marías, Puerto Rico
  7. 2.0 7 km ESE of La Parguera, Puerto Rico
  8. 1.9 21 km S of La Parguera, Puerto Rico
  9. 1.6 2 km S of Cabo Rojo, Puerto Rico
  10. 2.0 0 km NW of Liborio Negron Torres, Puerto Rico
  11. 2.1 14 km S of Pole Ojea, Puerto Rico
  12. 2.1 3 km SSE of Pole Ojea, Puerto Rico
  13. 2.7 Puerto Rico region
  14. 2.6 8 km WNW of Puerto Real, Puerto Rico
  15. 2.5 6 km W of Hormigueros, 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.