QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Puerto Rico region

Yes. A magnitude 3.1 earthquake was recorded in the Puerto Rico region, at 9:15 pm AST on 16 June 2017 (01:15 UTC), 35 km deep.

· 35 km deep · released about 1,200 lb of TNT

10 km30 km60 km120 km N Loíza Municipio 101 kmToa Baja Municipio 104 kmCataño Municipio 104 kmDorado Municipio 104 kmSan Juan Municipio 105 kmCarolina Municipio 106 kmRío Grande Municipio 109 kmVega Alta Municipio 111 kmLuquillo Municipio 111 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
35 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 101 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3372 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 20 km (12 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 1,200 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 6.7 280,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 12,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 8,800× the energy of this one
  4. This earthquake M 3.1 about 1,200 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.3× 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 19.3518, -65.9130. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Loíza Municipio, PR 101 km (63 mi) S earthquakes near Loíza Municipio
Toa Baja Municipio, PR 104 km (64 mi) SSW earthquakes near Toa Baja Municipio
Cataño Municipio, PR 104 km (65 mi) SSW earthquakes near Cataño Municipio
Dorado Municipio, PR 104 km (65 mi) SSW earthquakes near Dorado Municipio
San Juan Municipio, PR 105 km (65 mi) S earthquakes near San Juan Municipio
Carolina Municipio, PR 106 km (66 mi) S earthquakes near Carolina Municipio

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

Aftershocks so far

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

  1. 2.8 71 km N of Suárez, Puerto Rico
  2. 3.1 62 km N of Loíza, Puerto Rico
  3. 3.3 115 km N of San Juan, Puerto Rico
  4. 3.2 57 km N of San Juan, Puerto Rico
  5. 3.2 110 km N of Brenas, Puerto Rico
  6. 3.0 88 km N of San Juan, Puerto Rico
  7. 3.2 112 km N of Suárez, Puerto Rico
  8. 3.3 74 km N of San Juan, Puerto Rico
  9. 3.1 83 km N of Brenas, Puerto Rico
  10. 3.3 108 km N of San Juan, Puerto Rico
  11. 3.1 111 km N of San Juan, Puerto Rico
  12. 3.5 106 km N of San Juan, Puerto Rico
  13. 3.0 67 km NNE of Suárez, Puerto Rico
  14. 3.5 116 km N of San Juan, Puerto Rico
  15. 2.9 76 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.

On USGS

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