QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

108 km NNE of Suárez, Puerto Rico

Yes. A magnitude 3.1 earthquake was recorded 108 km NNE of Suárez, Puerto Rico, at 8:41 pm AST on 4 November 2017 (00:41 UTC), 64 km deep.

· 64 km deep · released about 1,600 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Fajardo Municipio 110 kmLoíza Municipio 111 kmLuquillo Municipio 113 kmRío Grande Municipio 114 kmCarolina Municipio 117 kmSan Juan Municipio 118 kmCataño Municipio 120 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
64 km below the surface
Felt
no reports yet
Nearest
Fajardo Municipio, 110 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3207 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 it was probably too small to be felt, even directly above it. 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 1,600 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 210,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 9,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 6,700× the energy of this one
  4. This earthquake M 3.1 about 1,600 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.7× 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.3 on 2016-09-04 — about 53 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 5.1 122 km NNE of Vieques, Puerto Rico · 28 km E of this epicentre
  2. 5.1 92 km N of Suárez, Puerto Rico · 20 km SW of this epicentre
  3. 5.0 73 km NNE of Vieques, Puerto Rico · 43 km SSE of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 19.3790, -65.5805. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fajardo Municipio, PR 110 km (69 mi) S earthquakes near Fajardo Municipio
Loíza Municipio, PR 111 km (69 mi) SSW earthquakes near Loíza Municipio
Luquillo Municipio, PR 113 km (70 mi) S earthquakes near Luquillo Municipio
Río Grande Municipio, PR 114 km (71 mi) SSW earthquakes near Río Grande Municipio
Carolina Municipio, PR 117 km (72 mi) SSW earthquakes near Carolina Municipio
San Juan Municipio, PR 118 km (73 mi) SSW earthquakes near San Juan Municipio

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

Aftershocks so far

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

  1. 3.2 93 km N of Loíza, Puerto Rico
  2. 3.3 98 km N of Suárez, Puerto Rico
  3. 3.3 111 km NNW of Charlotte Amalie, U.S. Virgin Islands
  4. 3.3 100 km NNW of Charlotte Amalie, U.S. Virgin Islands
  5. 2.9 96 km N of San Juan, Puerto Rico
  6. 3.4 107 km NNW of Charlotte Amalie, U.S. Virgin Islands
  7. 3.4 116 km N of Charlotte Amalie, U.S. Virgin Islands
  8. 4.5 109 km N of Culebra, Puerto Rico
  9. 3.2 98 km N of Culebra, Puerto Rico
  10. 3.4 125 km NNE of Vieques, Puerto Rico
  11. 3.7 115 km N of Culebra, Puerto Rico
  12. 3.0 101 km NNE of Vieques, Puerto Rico
  13. 3.4 128 km N of San Juan, Puerto Rico
  14. 3.3 136 km NNE of Vieques, Puerto Rico
  15. 3.4 97 km NNE 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.