QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

Earthquake near Palo Seco, PR

Yes: an earthquake was likely felt in Palo Seco in the last 24 hours. M 2.9, 28 km (17 mi) SE of Palo Seco, at 5:20 pm AST on 11 November 2026 (21:20 UTC); the estimated shaking in Palo Seco was intensity II (weak). 1 person has reported feeling it to USGS. Every earthquake near Palo Seco

This page: a magnitude 1.5 earthquake was recorded 3 km (2 mi) west of Palo Seco, PR, at 3:39 am AST on 11 September 2018 (07:39 UTC), 21 km deep.

USGS: 3 km W of Palo Seco, Puerto Rico

45 km (28 mi) SSE of San Juan, PR · 26 km (16 mi) SSE of Caguas, PR

3:39 am AST, Sep 11, 2018 · · 21 km deep · released about 5.6 lb of TNT

Every earthquake near Palo Seco Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Patillas Municipio 2 kmMaunabo Municipio 8 kmArroyo Municipio 9 kmYabucoa Municipio 13 kmSan Lorenzo Municipio 15 kmGuayama Municipio 18 kmCayey Municipio 22 kmLas Piedras Municipio 22 kmHumacao Municipio 24 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
3:39 am AST on 11 September 2018 ()
Where
3 km (2 mi) west of Palo Seco, PR · earthquakes near Palo Seco
Magnitude
M 1.5 (md)
Depth
21 km below the surface
Felt
no reports yet
Nearest
Patillas Municipio, 2 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2984 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 Palo Seco, 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: Lamboglia, Patillas, Palmas, Maunabo, Playita, Rosa Sanchez.

How big was it?

This earthquake released about 5.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.6 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

The largest earthquake within 50 km since 2016 was M 4.6 on 2016-12-05 — about 43,000 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 · 33 km NNW 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 18.0085, -65.9688. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Patillas Municipio, PR 2 km (1 mi) WSW earthquakes near Patillas Municipio
Maunabo Municipio, PR 8 km (5 mi) E earthquakes near Maunabo Municipio
Arroyo Municipio, PR 9 km (5 mi) WSW earthquakes near Arroyo Municipio
Yabucoa Municipio, PR 13 km (8 mi) ENE earthquakes near Yabucoa Municipio
San Lorenzo Municipio, PR 15 km (10 mi) N earthquakes near San Lorenzo Municipio
Guayama Municipio, PR 18 km (11 mi) WSW earthquakes near Guayama Municipio

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

Aftershocks so far

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

  1. 2.0 5 km S of Salinas, Puerto Rico
  2. 2.5 4 km SW of Patillas, Puerto Rico
  3. 1.8 18 km ESE of El Negro, Puerto Rico
  4. 1.9 2 km N of Carolina, Puerto Rico
  5. 1.9 11 km S of Emajagua, Puerto Rico
  6. 2.0 7 km SE of Arroyo, Puerto Rico
  7. 2.1 4 km ESE of Palmarejo, Puerto Rico
  8. 2.0 Puerto Rico region
  9. 2.0 3 km SSW of Jauca, Puerto Rico
  10. 2.3 2 km SSW of Jauca, Puerto Rico
  11. 2.0 2 km SSW of Jauca, Puerto Rico
  12. 2.0 2 km SE of Santa Isabel, Puerto Rico
  13. 2.1 1 km SSE of G. L. Garcia, Puerto Rico
  14. 2.5 11 km S of Emajagua, Puerto Rico
  15. 1.9 2 km S of Las Ochenta, 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.