QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9md

98 km NNE of San Juan, Puerto Rico

· 24 km deep · released about 11 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Loíza Municipio 98 kmCataño Municipio 102 kmSan Juan Municipio 103 kmToa Baja Municipio 103 kmCarolina Municipio 103 kmDorado Municipio 104 kmRío Grande Municipio 105 kmLuquillo Municipio 107 kmFajardo Municipio 107 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
Magnitude
M 3.9 (md)
Depth
24 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Loíza Municipio, 98 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1317 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 15,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 660× the energy of this one
  3. Magna, Utah 2020 M 5.7 470× the energy of this one
  4. This earthquake M 3.9 about 11 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 24× 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.

Where

Epicentre 19.3206, -65.8500. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Loíza Municipio, PR 98 km (61 mi) N of here earthquakes near Loíza Municipio
Cataño Municipio, PR 102 km (64 mi) NNE of here earthquakes near Cataño Municipio
San Juan Municipio, PR 103 km (64 mi) NNE of here earthquakes near San Juan Municipio
Toa Baja Municipio, PR 103 km (64 mi) NNE of here earthquakes near Toa Baja Municipio
Carolina Municipio, PR 103 km (64 mi) N of here earthquakes near Carolina Municipio
Dorado Municipio, PR 104 km (64 mi) NNE of here earthquakes near Dorado Municipio

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

Aftershocks so far

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

  1. 3.3 82 km N of San Juan, Puerto Rico
  2. 3.2 78 km N of Brenas, Puerto Rico
  3. 3.3 131 km NNE of Vieques, Puerto Rico
  4. 3.5 132 km NNE of Vieques, Puerto Rico
  5. 3.6 Puerto Rico region
  6. 3.1 57 km N of Suárez, Puerto Rico
  7. 3.4 61 km N of Loíza, Puerto Rico
  8. 3.4 Puerto Rico region
  9. 3.3 52 km N of Suárez, Puerto Rico
  10. 3.7 114 km N of Suárez, Puerto Rico
  11. 3.6 78 km NNE of San Juan, Puerto Rico
  12. 3.6 135 km N of Suárez, Puerto Rico
  13. 3.2 94 km NNE of San Juan, Puerto Rico
  14. 3.9 107 km NNE of San Juan, Puerto Rico
  15. 3.9 88 km N of Suárez, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.1 on 2022-12-09 — it released about 2.1 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.