QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near San Juan, PR

No earthquake was likely felt in San Juan in the 24 hours to 11:29 am AST (15:29 UTC). The last one was M 4.1, 99 km (62 mi) SE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near San Juan

This page: a magnitude 1.8 earthquake was recorded 46 km (28 mi) southwest of San Juan, PR, at 4:04 pm AST on 1 November 2023 (20:04 UTC), 8.4 km deep.

USGS: 6 km SSW of Orocovis, Puerto Rico

45 km (28 mi) SW of San Juan, PR · 30 km (19 mi) NE of Ponce, PR

4:04 pm AST, Nov 1, 2023 · · 8.4 km deep · released about 17 lb of TNT

Every earthquake near San Juan Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orocovis Municipio 7 kmVillalba Municipio 8 kmCoamo Municipio 9 kmBarranquitas Municipio 11 kmAibonito Municipio 15 kmMorovis Municipio 17 kmCorozal Municipio 17 kmCiales Municipio 18 kmJayuya 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
4:04 pm AST on 1 November 2023 ()
Where
46 km (28 mi) southwest of San Juan, PR · earthquakes near San Juan
Magnitude
M 1.8 (md)
Depth
8.4 km below the surface
Felt
no reports yet
Nearest
Orocovis Municipio, 7 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1106 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 11 km (7 mi) from the epicentre. In San Juan, 46 km away, the estimate is intensity I (not felt). 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.

Likely felt in: Coamo 11 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 17 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 6.4 on 2020-01-07 — about 7,200,000 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 5.8 12 km N of Garrochales, Puerto Rico · 47 km NNW of this epicentre
  2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 30 km ENE of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 38 km N 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 18.1683, -66.4048. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orocovis Municipio, PR 7 km (4 mi) NNW earthquakes near Orocovis Municipio
Villalba Municipio, PR 8 km (5 mi) WSW earthquakes near Villalba Municipio
Coamo Municipio, PR 9 km (5 mi) SE earthquakes near Coamo Municipio
Barranquitas Municipio, PR 11 km (7 mi) ENE earthquakes near Barranquitas Municipio
Aibonito Municipio, PR 15 km (10 mi) ESE earthquakes near Aibonito Municipio
Morovis Municipio, PR 17 km (10 mi) N earthquakes near Morovis Municipio

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

Aftershocks so far

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

  1. 1.9 1 km E of Indios, Puerto Rico
  2. 3.5 3 km WSW of Manatí, Puerto Rico
  3. 2.9 2 km SSW of Santo Domingo, Puerto Rico
  4. 2.2 2 km WSW of Potala Pastillo, Puerto Rico
  5. 2.5 4 km WNW of Adjuntas, Puerto Rico
  6. 2.3 4 km WNW of Ponce, Puerto Rico
  7. 3.0 3 km WNW of San Lorenzo, Puerto Rico
  8. 3.3 1 km NNE of Indios, Puerto Rico
  9. 2.0 5 km S of Salinas, Puerto Rico
  10. 2.9 4 km SSE of Salinas, Puerto Rico
  11. 2.2 1 km WNW of Guayanilla, Puerto Rico
  12. 2.5 7 km S of Orocovis, Puerto Rico
  13. 2.4 1 km WSW of Guayanilla, Puerto Rico
  14. 2.2 7 km SE of Indios, Puerto Rico
  15. 2.1 7 km NW of Coto Laurel, 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.