QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Vieques, PR

No earthquake was likely felt in Vieques in the 24 hours to 5:46 pm AST (21:46 UTC). The last one was M 4.1, 74 km (46 mi) SE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Vieques

This page: a magnitude 2.9 earthquake was recorded 48 km (30 mi) north of Vieques, PR, at 2:32 pm AST on 15 December 2021 (18:32 UTC), 43 km deep.

USGS: 47 km N of Suárez, Puerto Rico

58 km (36 mi) NNE of San Juan, PR · 53 km (33 mi) NNE of Carolina, PR

2:32 pm AST, Dec 15, 2021 · · 43 km deep · released about 700 lb of TNT

Every earthquake near Vieques Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Loíza Municipio 49 kmRío Grande Municipio 53 kmLuquillo Municipio 54 kmCarolina Municipio 55 kmFajardo Municipio 56 kmSan Juan Municipio 57 kmCanóvanas Municipio 59 kmCataño Municipio 60 kmToa Baja Municipio 62 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
2:32 pm AST on 15 December 2021 ()
Where
48 km (30 mi) north of Vieques, PR · earthquakes near Vieques
Magnitude
M 2.9 (md)
Depth
43 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 49 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1792 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. In Vieques, 48 km away, the estimate is intensity II (weak). 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 700 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 15,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.4× the energy of this one
  4. This earthquake M 2.9 about 700 lb of TNT

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 4.0 on 2016-09-05 — about 43 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 92 km N of Suárez, Puerto Rico · 45 km N of this epicentre
  2. 5.0 73 km NNE of Vieques, Puerto Rico · 34 km ENE 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 18.8533, -65.7783. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Loíza Municipio, PR 49 km (30 mi) SSW earthquakes near Loíza Municipio
Río Grande Municipio, PR 53 km (33 mi) S earthquakes near Río Grande Municipio
Luquillo Municipio, PR 54 km (34 mi) S earthquakes near Luquillo Municipio
Carolina Municipio, PR 55 km (34 mi) SSW earthquakes near Carolina Municipio
Fajardo Municipio, PR 56 km (35 mi) SSE earthquakes near Fajardo Municipio
San Juan Municipio, PR 57 km (35 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

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

  1. 3.3 59 km N of Loíza, Puerto Rico
  2. 3.1 52 km N of Loíza, Puerto Rico
  3. 3.1 77 km N of Suárez, Puerto Rico
  4. 3.3 Puerto Rico region
  5. 3.0 60 km N of Suárez, Puerto Rico
  6. 3.1 60 km N of Suárez, Puerto Rico
  7. 3.2 72 km N of Suárez, Puerto Rico
  8. 3.1 65 km N of Suárez, Puerto Rico
  9. 3.1 64 km N of Suárez, Puerto Rico
  10. 3.2 18 km N of Suárez, Puerto Rico
  11. 3.2 71 km N of San Juan, Puerto Rico
  12. 3.1 32 km N of San Juan, Puerto Rico
  13. 2.9 41 km NNE of Suárez, Puerto Rico
  14. 3.3 67 km NNE of Luquillo, Puerto Rico
  15. 3.3 60 km N of Culebra, 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.