QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Earthquake near San Juan, PR

No earthquake was likely felt in San Juan in the 24 hours to 4:38 pm AST (20:38 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 3.1 earthquake was recorded 11 km (7 mi) northwest of San Juan, PR, at 5:10 pm AST on 15 December 2022 (21:10 UTC), 99 km deep. 1 person has reported feeling it to USGS.

USGS: 10 km NW of San Juan, Puerto Rico

19 km (12 mi) NW of San Juan, PR · 18 km (11 mi) N of Bayamón, PR

5:10 pm AST, Dec 15, 2022 · · 99 km deep · released about 1,500 lb of TNT

10 km30 km60 km120 km N Toa Baja Municipio 10 kmCataño Municipio 11 kmDorado Municipio 13 kmSan Juan Municipio 17 kmBayamón Municipio 22 kmToa Alta Municipio 22 kmVega Alta Municipio 22 kmGuaynabo Municipio 23 kmLoíza 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
5:10 pm AST on 15 December 2022 ()
Where
11 km (7 mi) northwest of San Juan, PR · earthquakes near San Juan
Magnitude
M 3.1 (md)
Depth
99 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Toa Baja Municipio, 10 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1426 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. In San Juan, 11 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: Levittown, Cataño, Ingenio, Sabana Seca, Dorado, Toa Baja.

How big was it?

This earthquake released about 1,500 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 230,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 10,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,200× the energy of this one
  4. This earthquake M 3.1 about 1,500 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.6× 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 4.8 on 2017-08-18 — about 320 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 · 42 km W of this epicentre
  2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 32 km S of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 19 km WSW 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 18.5440, -66.1635. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Toa Baja Municipio, PR 10 km (6 mi) SSW earthquakes near Toa Baja Municipio
Cataño Municipio, PR 11 km (7 mi) S earthquakes near Cataño Municipio
Dorado Municipio, PR 13 km (8 mi) SW earthquakes near Dorado Municipio
San Juan Municipio, PR 17 km (10 mi) SE earthquakes near San Juan Municipio
Bayamón Municipio, PR 22 km (13 mi) S earthquakes near Bayamón Municipio
Toa Alta Municipio, PR 22 km (13 mi) SSW earthquakes near Toa Alta 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. 2.2 3 km E of Bayamon, Puerto Rico
  2. 2.7 Puerto Rico region
  3. 2.8 Puerto Rico region
  4. 3.2 10 km NNW of Levittown, Puerto Rico
  5. 3.1 6 km ENE of San Juan, Puerto Rico
  6. 2.8 15 km NE of Arecibo, Puerto Rico
  7. 3.4 Puerto Rico region
  8. 3.3 49 km N of San Juan, Puerto Rico
  9. 3.3 Puerto Rico region
  10. 3.4 2 km SE of Aguas Buenas, Puerto Rico
  11. 2.8 23 km N of Tierras Nuevas Poniente, Puerto Rico
  12. 3.4 3 km NNE of Benitez, Puerto Rico
  13. 2.8 0 km SSW of San Juan, Puerto Rico
  14. 2.5 20 km NNW of Brenas, Puerto Rico
  15. 2.1 6 km NE of Orocovis, 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.