QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

Earthquake near San Juan, PR

No earthquake was likely felt in San Juan in the 24 hours to 10:17 am AST (14:17 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 2.8 earthquake was recorded in San Juan, PR, at 8:52 pm AST on 6 April 2023 (00:52 UTC), 82 km deep. 1 person has reported feeling it to USGS.

USGS: 0 km SSW of San Juan, Puerto Rico

8 km (5 mi) NW of San Juan, PR

8:52 pm AST, Apr 6, 2023 · · 82 km deep · released about 550 lb of TNT

10 km30 km60 km120 km N Cataño Municipio 5 kmSan Juan Municipio 6 kmToa Baja Municipio 9 kmGuaynabo Municipio 13 kmBayamón Municipio 14 kmCarolina Municipio 16 kmDorado Municipio 16 kmLoíza Municipio 17 kmTrujillo Alto Municipio 17 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
8:52 pm AST on 6 April 2023 ()
Where
in San Juan, PR · earthquakes near San Juan
Magnitude
M 2.8 (md)
Depth
82 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Cataño Municipio, 5 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1315 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: Cataño, Eleanor Roosevelt, Levittown, Bayamón, Sabana Seca, Guaynabo.

How big was it?

This earthquake released about 550 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 28,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 19,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.7× the energy of this one
  4. This earthquake M 2.8 about 550 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 220 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 · 50 km WNW of this epicentre
  2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 22 km S of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 25 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 18.4580, -66.1077. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cataño Municipio, PR 5 km (3 mi) WSW earthquakes near Cataño Municipio
San Juan Municipio, PR 6 km (4 mi) SE earthquakes near San Juan Municipio
Toa Baja Municipio, PR 9 km (6 mi) W earthquakes near Toa Baja Municipio
Guaynabo Municipio, PR 13 km (8 mi) S earthquakes near Guaynabo Municipio
Bayamón Municipio, PR 14 km (9 mi) SSW earthquakes near Bayamón Municipio
Carolina Municipio, PR 16 km (10 mi) ESE earthquakes near Carolina Municipio

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

Aftershocks so far

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

  1. 3.3 Puerto Rico region
  2. 2.9 8 km NNW of Coamo, Puerto Rico
  3. 3.0 1 km E of Jagual, Puerto Rico
  4. 2.4 8 km S of Orocovis, Puerto Rico
  5. 2.9 Puerto Rico region
  6. 3.3 8 km S of Orocovis, Puerto Rico
  7. 3.0 22 km N of San Juan, Puerto Rico
  8. 2.7 2 km E of Santa Clara, Puerto Rico
  9. 3.1 37 km N of Suárez, Puerto Rico
  10. 3.0 1 km ENE of Bayamon, Puerto Rico
  11. 3.3 7 km NNW of Brenas, Puerto Rico
  12. 3.2 1 km NE of Bajandas, Puerto Rico
  13. 3.1 4 km WNW of Santa Clara, Puerto Rico
  14. 2.0 1 km NE of La Plena, Puerto Rico
  15. 3.0 3 km NE of La Plena, 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.