QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

51 km N of San Juan, Puerto Rico

· 20 km deep · released about 1,400 lb of TNT

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10 km30 km60 km120 km N Dorado Municipio 51 kmToa Baja Municipio 53 kmCataño Municipio 54 kmVega Alta Municipio 57 kmVega Baja Municipio 58 kmSan Juan Municipio 58 kmLoíza Municipio 59 kmManatí Municipio 63 kmToa Alta Municipio 63 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 3.1 (md)
Depth
20 km below the surface
Felt
no reports yet
Nearest
Dorado Municipio, 51 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1198 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

How big was it?

This earthquake released about 1,400 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 6.7 240,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,700× the energy of this one
  4. This earthquake M 3.1 about 1,400 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.5× 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 18.9307, -66.1797. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Dorado Municipio, PR 51 km (32 mi) N of here earthquakes near Dorado Municipio
Toa Baja Municipio, PR 53 km (33 mi) N of here earthquakes near Toa Baja Municipio
Cataño Municipio, PR 54 km (34 mi) N of here earthquakes near Cataño Municipio
Vega Alta Municipio, PR 57 km (36 mi) NNE of here earthquakes near Vega Alta Municipio
Vega Baja Municipio, PR 58 km (36 mi) NNE of here earthquakes near Vega Baja Municipio
San Juan Municipio, PR 58 km (36 mi) NNW of here earthquakes near San Juan 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 37 km N of San Juan, Puerto Rico
  2. 3.2 63 km N of San Juan, Puerto Rico
  3. 3.0 49 km N of Brenas, Puerto Rico
  4. 3.6 71 km N of Tierras Nuevas Poniente, Puerto Rico
  5. 3.9 98 km N of Brenas, Puerto Rico
  6. 3.0 Puerto Rico region
  7. 3.3 49 km N of Tierras Nuevas Poniente, Puerto Rico
  8. 3.0 67 km N of Brenas, Puerto Rico
  9. 2.5 17 km NNW of Brenas, Puerto Rico
  10. 3.1 Puerto Rico region
  11. 3.0 53 km N of Loíza, Puerto Rico
  12. 2.5 39 km N of Tierras Nuevas Poniente, Puerto Rico
  13. 3.3 Puerto Rico region
  14. 3.1 52 km N of Brenas, Puerto Rico
  15. 3.4 52 km N of Brenas, 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 340 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.