QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0md

53 km N of Brenas, Puerto Rico

Yes. A magnitude 3.0 earthquake was recorded 53 km N of Brenas, Puerto Rico, 64 km (40 mi) NNW of San Juan, PR, at 7:04 pm AST on 16 February 2021 (23:04 UTC), 39 km deep.

64 km (40 mi) NNW of San Juan, PR

· 39 km deep · released about 990 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Dorado Municipio 52 kmToa Baja Municipio 55 kmVega Baja Municipio 56 kmVega Alta Municipio 57 kmCataño Municipio 58 kmManatí Municipio 60 kmBarceloneta Municipio 60 kmSan Juan Municipio 62 kmToa Alta Municipio 65 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 3.0 (md)
Depth
39 km below the surface
Felt
no reports yet
Nearest
Dorado Municipio, 52 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2094 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 990 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 340,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 15,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 990 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 4.8 on 2017-08-18 — about 480 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 5.9 78 km N of Arecibo, Puerto Rico · 46 km NW of this epicentre
  2. 5.7 78 km N of Tierras Nuevas Poniente, Puerto Rico · 38 km NW of this epicentre
  3. 5.5 64 km N of Tierras Nuevas Poniente, Puerto Rico · 23 km WNW of this epicentre
  4. 5.1 66 km N of Brenas, Puerto Rico · 16 km NNW of this epicentre
  5. 5.0 3 km N of Brenas, Puerto Rico · 50 km S 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 18.9455, -66.2846. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Dorado Municipio, PR 52 km (33 mi) S earthquakes near Dorado Municipio
Toa Baja Municipio, PR 55 km (34 mi) S earthquakes near Toa Baja Municipio
Vega Baja Municipio, PR 56 km (35 mi) SSW earthquakes near Vega Baja Municipio
Vega Alta Municipio, PR 57 km (35 mi) S earthquakes near Vega Alta Municipio
Cataño Municipio, PR 58 km (36 mi) SSE earthquakes near Cataño Municipio
Manatí Municipio, PR 60 km (37 mi) SSW earthquakes near Manatí Municipio

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

Aftershocks so far

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

  1. 3.3 75 km N of San Juan, Puerto Rico
  2. 3.0 35 km N of Tierras Nuevas Poniente, Puerto Rico
  3. 3.3 81 km NNE of San Juan, Puerto Rico
  4. 3.2 74 km N of San Juan, Puerto Rico
  5. 3.5 83 km N of San Juan, Puerto Rico
  6. 3.2 72 km N of San Juan, Puerto Rico
  7. 3.2 67 km N of Tierras Nuevas Poniente, Puerto Rico
  8. 3.4 61 km N of Arecibo, Puerto Rico
  9. 3.1 68 km N of Arecibo, Puerto Rico
  10. 3.2 38 km N of San Juan, Puerto Rico
  11. 3.3 69 km N of Brenas, Puerto Rico
  12. 3.5 14 km NNW of Brenas, Puerto Rico
  13. 3.5 22 km NNE of Tierras Nuevas Poniente, Puerto Rico
  14. 3.4 85 km N of San Juan, Puerto Rico
  15. 3.2 80 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.