QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near San Juan, PR

No earthquake was likely felt in San Juan in the 24 hours to 4:28 pm AST (20:28 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 2.9 earthquake was recorded 3 km (2 mi) east of San Juan, PR, at 12:23 am AST on 21 December 2022 (04:23 UTC), 91 km deep.

USGS: 3 km E of San Juan, Puerto Rico

7 km (5 mi) N of San Juan, PR

12:23 am AST, Dec 21, 2022 · · 91 km deep · released about 780 lb of TNT

Every earthquake near San Juan Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Juan Municipio 5 kmCataño Municipio 8 kmToa Baja Municipio 13 kmCarolina Municipio 14 kmLoíza Municipio 14 kmGuaynabo Municipio 15 kmTrujillo Alto Municipio 17 kmBayamón Municipio 17 kmDorado 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
12:23 am AST on 21 December 2022 ()
Where
3 km (2 mi) east of San Juan, PR · earthquakes near San Juan
Magnitude
M 2.9 (md)
Depth
91 km below the surface
Felt
no reports yet
Nearest
San Juan Municipio, 5 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1421 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, 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: Cataño, Eleanor Roosevelt, Levittown, Bayamón, Sabana Seca, Guaynabo.

How big was it?

This earthquake released about 780 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 19,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 14,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.2× the energy of this one
  4. This earthquake M 2.9 about 780 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 4.4 on 2018-12-09 — about 150 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 24 km SSW of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 28 km W 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 18.4707, -66.0737. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan Municipio, PR 5 km (3 mi) S earthquakes near San Juan Municipio
Cataño Municipio, PR 8 km (5 mi) WSW earthquakes near Cataño Municipio
Toa Baja Municipio, PR 13 km (8 mi) W earthquakes near Toa Baja Municipio
Carolina Municipio, PR 14 km (9 mi) SE earthquakes near Carolina Municipio
Loíza Municipio, PR 14 km (9 mi) ESE earthquakes near Loíza Municipio
Guaynabo Municipio, PR 15 km (9 mi) SSW earthquakes near Guaynabo Municipio

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

Aftershocks so far

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

  1. 2.2 3 km E of Bayamon, Puerto Rico
  2. 3.1 8 km SSW of Orocovis, Puerto Rico
  3. 2.7 Puerto Rico region
  4. 2.9 1 km W of Punta Santiago, Puerto Rico
  5. 2.8 Puerto Rico region
  6. 3.2 10 km NNW of Levittown, Puerto Rico
  7. 3.1 6 km ENE of San Juan, Puerto Rico
  8. 3.4 Puerto Rico region
  9. 3.3 49 km N of San Juan, Puerto Rico
  10. 2.9 5 km S of Jagual, Puerto Rico
  11. 2.0 1 km NNW of Punta Santiago, Puerto Rico
  12. 3.4 2 km SE of Aguas Buenas, Puerto Rico
  13. 2.4 2 km NW of Punta Santiago, Puerto Rico
  14. 2.0 4 km NW of Yaurel, Puerto Rico
  15. 3.4 3 km NNE of Benitez, 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.