QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

75 km N of San Juan, Puerto Rico

· 15 km deep · released about 2 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Loíza Municipio 77 kmToa Baja Municipio 78 kmCataño Municipio 79 kmDorado Municipio 79 kmSan Juan Municipio 80 kmCarolina Municipio 82 kmVega Alta Municipio 86 kmVega Baja Municipio 87 kmRío Grande Municipio 87 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
15 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 77 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 32 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 2 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 83,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 3,700× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,600× the energy of this one
  4. This earthquake M 3.4 about 2 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4.3× 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 19.1373, -65.9947. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Loíza Municipio, PR 77 km (48 mi) N of here earthquakes near Loíza Municipio
Toa Baja Municipio, PR 78 km (49 mi) NNE of here earthquakes near Toa Baja Municipio
Cataño Municipio, PR 79 km (49 mi) NNE of here earthquakes near Cataño Municipio
Dorado Municipio, PR 79 km (49 mi) NNE of here earthquakes near Dorado Municipio
San Juan Municipio, PR 80 km (50 mi) N of here earthquakes near San Juan Municipio
Carolina Municipio, PR 82 km (51 mi) N of here earthquakes near Carolina Municipio

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

Aftershocks so far

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

  1. 3.1 75 km N of Brenas, Puerto Rico
  2. 3.3 110 km N of Suárez, Puerto Rico
  3. 3.2 93 km N of San Juan, Puerto Rico
  4. 3.3 76 km NNE of Vieques, Puerto Rico
  5. 3.7 117 km N of San Juan, Puerto Rico
  6. 2.9 65 km N of Tierras Nuevas Poniente, Puerto Rico
  7. 3.3 80 km N of San Juan, 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 120 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.