QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

55 km NNE of San Juan, Puerto Rico

Yes. A magnitude 3.1 earthquake was recorded 55 km NNE of San Juan, Puerto Rico, 61 km (38 mi) NNE of San Juan, PR, at 2:40 pm AST on 11 May 2026 (18:40 UTC), 22 km deep.

61 km (38 mi) NNE of San Juan, PR · 58 km (36 mi) N of Carolina, PR

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

10 km30 km60 km120 km N Loíza Municipio 54 kmSan Juan Municipio 59 kmCataño Municipio 59 kmCarolina Municipio 60 kmToa Baja Municipio 60 kmDorado Municipio 62 kmRío Grande Municipio 63 kmLuquillo Municipio 66 kmTrujillo Alto Municipio 67 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
22 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 54 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 184 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 36 km (22 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 1,400 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.8 on 2017-08-18 — about 340 times the energy of this one.

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

  1. 5.1 66 km N of Brenas, Puerto Rico · 50 km WNW of this epicentre
  2. 5.1 92 km N of Suárez, Puerto Rico · 42 km NNE of this epicentre
  3. 5.0 73 km NNE of Vieques, Puerto Rico · 45 km E 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 18.9318, -65.9190. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Loíza Municipio, PR 54 km (34 mi) S earthquakes near Loíza Municipio
San Juan Municipio, PR 59 km (37 mi) SSW earthquakes near San Juan Municipio
Cataño Municipio, PR 59 km (37 mi) SSW earthquakes near Cataño Municipio
Carolina Municipio, PR 60 km (37 mi) S earthquakes near Carolina Municipio
Toa Baja Municipio, PR 60 km (37 mi) SSW earthquakes near Toa Baja Municipio
Dorado Municipio, PR 62 km (39 mi) SW earthquakes near Dorado Municipio

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

Aftershocks so far

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

  1. 2.9 75 km NNE of Vieques, Puerto Rico
  2. 3.0 52 km N of San Juan, Puerto Rico
  3. 3.1 62 km NNE of Luquillo, Puerto Rico
  4. 3.0 49 km N of Suárez, Puerto Rico
  5. 3.0 66 km N of San Juan, Puerto Rico
  6. 3.3 53 km N of Brenas, Puerto Rico
  7. 3.1 22 km NNE of Brenas, Puerto Rico
  8. 3.0 34 km NNE of San Juan, Puerto Rico
  9. 2.9 41 km NNE of Luquillo, Puerto Rico
  10. 3.1 75 km N of Brenas, Puerto Rico
  11. 3.2 93 km N of San Juan, Puerto Rico
  12. 3.3 76 km NNE of Vieques, Puerto Rico
  13. 3.3 80 km N of San Juan, Puerto Rico
  14. 3.4 75 km N of San Juan, Puerto Rico
  15. 3.1 63 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.

On USGS

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