QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

9 km NNE of San Juan, Puerto Rico

· 105 km deep · released about 2.1 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Cataño Municipio 14 kmSan Juan Municipio 15 kmToa Baja Municipio 16 kmLoíza Municipio 19 kmDorado Municipio 21 kmCarolina Municipio 21 kmGuaynabo Municipio 23 kmBayamón Municipio 24 kmTrujillo Alto 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
Magnitude
M 3.4 (md)
Depth
105 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Cataño Municipio, 14 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 747 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 2.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 80,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 3,600× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,500× the energy of this one
  4. This earthquake M 3.4 about 2.1 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4.4× 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 18.5527, -66.0853. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Cataño Municipio, PR 14 km (9 mi) NNE of here earthquakes near Cataño Municipio
San Juan Municipio, PR 15 km (9 mi) N of here earthquakes near San Juan Municipio
Toa Baja Municipio, PR 16 km (10 mi) NE of here earthquakes near Toa Baja Municipio
Loíza Municipio, PR 19 km (12 mi) NW of here earthquakes near Loíza Municipio
Dorado Municipio, PR 21 km (13 mi) ENE of here earthquakes near Dorado Municipio
Carolina Municipio, PR 21 km (13 mi) NW of here earthquakes near Carolina Municipio

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

Aftershocks so far

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

  1. 3.1 1 km S of Toa Alta, Puerto Rico
  2. 3.0 2 km ENE of Cidra, Puerto Rico
  3. 3.0 34 km N of Tierras Nuevas Poniente, Puerto Rico
  4. 3.3 7 km ESE of San Juan, Puerto Rico
  5. 2.3 5 km NW of Orocovis, Puerto Rico
  6. 2.0 5 km NNW of Orocovis, Puerto Rico
  7. 2.4 3 km NW of Orocovis, Puerto Rico
  8. 2.1 1 km ESE of Parcelas La Milagrosa, Puerto Rico
  9. 2.8 31 km N of Brenas, Puerto Rico
  10. 2.4 3 km NW of Orocovis, Puerto Rico
  11. 3.5 4 km ESE of G. L. Garcia, Puerto Rico
  12. 2.2 1 km SSW of G. L. Garcia, Puerto Rico
  13. 2.0 3 km NW of Orocovis, Puerto Rico
  14. 3.0 27 km NNE of Brenas, Puerto Rico
  15. 2.2 4 km NW 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.8 on 2017-08-18 — it released about 110 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.