QuakeIndex

Earthquake · reviewed by a seismologist

M 3.6md

Earthquake near Pájaros, PR

No earthquake was likely felt in Pájaros in the 24 hours to 10:09 am AST (14:09 UTC). The last one was M 4.8, 91 km (56 mi) WSW, at 9:19 am AST on 18 September 2026, estimated intensity III (weak) in town; 86 felt reports to USGS. Every earthquake near Pájaros

This page: a magnitude 3.6 earthquake was recorded in Pájaros, PR, at 5:00 am AST on 23 July 2023 (09:00 UTC), 112 km deep. 1 person has reported feeling it to USGS.

USGS: 0 km ENE of Pájaros, Puerto Rico

in Bayamón, PR

5:00 am AST, Jul 23, 2023 · · 112 km deep · released about 4.1 tons of TNT

Every earthquake near Pájaros Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Toa Alta Municipio 4 kmBayamón Municipio 5 kmToa Baja Municipio 10 kmNaranjito Municipio 10 kmCataño Municipio 10 kmGuaynabo Municipio 10 kmDorado Municipio 13 kmCorozal Municipio 14 kmVega Alta Municipio 15 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
5:00 am AST on 23 July 2023 ()
Where
in Pájaros, PR · earthquakes near Pájaros
Magnitude
M 3.6 (md)
Depth
112 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Toa Alta Municipio, 4 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1207 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. 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: Mucarabones, Candelaria, Toa Alta, Candelaria Arenas, Galateo, San José.

How big was it?

This earthquake released about 4.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 42,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,300× the energy of this one
  4. This earthquake M 3.6 about 4.1 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 8.5× more

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 2019-03-12 — about 30 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 · 43 km WNW of this epicentre
  2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 15 km SSE of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 20 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 18.3716, -66.2093. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Toa Alta Municipio, PR 4 km (2 mi) WSW earthquakes near Toa Alta Municipio
Bayamón Municipio, PR 5 km (3 mi) ESE earthquakes near Bayamón Municipio
Toa Baja Municipio, PR 10 km (6 mi) N earthquakes near Toa Baja Municipio
Naranjito Municipio, PR 10 km (6 mi) SSW earthquakes near Naranjito Municipio
Cataño Municipio, PR 10 km (6 mi) NE earthquakes near Cataño Municipio
Guaynabo Municipio, PR 10 km (7 mi) ESE earthquakes near Guaynabo Municipio

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

Aftershocks so far

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

  1. 2.8 1 km SSW of Cidra, Puerto Rico
  2. 2.3 4 km SSE of Salinas, Puerto Rico
  3. 2.7 5 km SSE of Salinas, Puerto Rico
  4. 2.5 Puerto Rico region
  5. 2.3 Puerto Rico region
  6. 3.2 2 km NNW of San Juan, Puerto Rico
  7. 2.6 3 km SSE of Salinas, Puerto Rico
  8. 3.6 Puerto Rico region
  9. 2.3 5 km SSE of Salinas, Puerto Rico
  10. 2.4 3 km SSE of Salinas, Puerto Rico
  11. 2.3 Puerto Rico region
  12. 3.3 4 km ENE of Guaynabo, Puerto Rico
  13. 2.6 8 km S of Orocovis, Puerto Rico
  14. 2.3 3 km S of Las Ochenta, Puerto Rico
  15. 2.4 4 km WSW of Central Aguirre, 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.