QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3md

121 km NNE of Suárez, Puerto Rico

Yes. A magnitude 3.3 earthquake was recorded 121 km NNE of Suárez, Puerto Rico, at 1:47 am AST on 23 April 2019 (05:47 UTC), 18 km deep.

· 18 km deep · released about 1.3 tons of TNT

10 km30 km60 km120 km N
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 3.3 (md)
Depth
18 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 123 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2678 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 48 km (30 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 1.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 130,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 5,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 4,100× the energy of this one
  4. This earthquake M 3.3 about 1.3 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.7× 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 4.5 on 2018-03-06 — about 65 times the energy of this one.

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

  1. 5.1 122 km NNE of Vieques, Puerto Rico · 33 km ESE of this epicentre
  2. 5.1 92 km N of Suárez, Puerto Rico · 30 km SSW 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 19.5070, -65.6095. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Loíza Municipio, PR 123 km (77 mi) SSW earthquakes near Loíza Municipio
Cataño Municipio, PR 131 km (81 mi) SSW earthquakes near Cataño Municipio
Toa Baja Municipio, PR 132 km (82 mi) SSW earthquakes near Toa Baja Municipio
Dorado Municipio, PR 134 km (83 mi) SSW earthquakes near Dorado Municipio
Vega Alta Municipio, PR 141 km (88 mi) SSW earthquakes near Vega Alta Municipio
Vega Baja Municipio, PR 143 km (89 mi) SW earthquakes near Vega Baja Municipio

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

Aftershocks so far

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

  1. 2.1 82 km NNE of Suárez, Puerto Rico
  2. 3.2 135 km NNE of Vieques, Puerto Rico
  3. 2.7 123 km NNE of Suárez, Puerto Rico
  4. 3.1 144 km NNE of Vieques, Puerto Rico
  5. 3.4 138 km NNE of Vieques, Puerto Rico
  6. 3.7 133 km NNE of Vieques, Puerto Rico
  7. 3.6 152 km NNE of Vieques, Puerto Rico
  8. 3.5 118 km NNE of Vieques, Puerto Rico
  9. 3.5 Puerto Rico region
  10. 3.0 78 km NNE of Vieques, Puerto Rico
  11. 2.7 106 km N of Culebra, Puerto Rico
  12. 2.9 127 km NNE of Vieques, Puerto Rico
  13. 3.3 163 km NNE of Vieques, Puerto Rico
  14. 2.7 137 km NNE of Vieques, Puerto Rico
  15. 2.4 117 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.