QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

65 km SSE of Arroyo, Puerto Rico

· 27 km deep · released about 1,300 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Arroyo Municipio 66 kmMaunabo Municipio 69 kmPatillas Municipio 69 kmGuayama Municipio 69 kmSalinas Municipio 74 kmYabucoa Municipio 76 kmSanta Isabel Municipio 79 kmCayey Municipio 83 kmSan Lorenzo Municipio 85 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
27 km below the surface
Felt
no reports yet
Nearest
Arroyo Municipio, 66 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 261 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 1,300 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 6.7 250,000× 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 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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 17.3848, -65.9377. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Arroyo Municipio, PR 66 km (41 mi) S of here earthquakes near Arroyo Municipio
Maunabo Municipio, PR 69 km (43 mi) S of here earthquakes near Maunabo Municipio
Patillas Municipio, PR 69 km (43 mi) S of here earthquakes near Patillas Municipio
Guayama Municipio, PR 69 km (43 mi) SSE of here earthquakes near Guayama Municipio
Salinas Municipio, PR 74 km (46 mi) SSE of here earthquakes near Salinas Municipio
Yabucoa Municipio, PR 76 km (47 mi) S of here earthquakes near Yabucoa Municipio

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

Aftershocks so far

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

  1. 3.3 98 km SSE of Emajagua, Puerto Rico
  2. 3.1 83 km SSE of Emajagua, Puerto Rico
  3. 2.8 49 km S of Central Aguirre, 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.