QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3md

1 km SW of San Sebastián, Puerto Rico

· 19 km deep · released about 1.4 tons of TNT

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10 km30 km60 km120 km N San Sebastián Municipio 3 kmMoca Municipio 10 kmLas Marías Municipio 12 kmAñasco Municipio 15 kmLares Municipio 15 kmQuebradillas Municipio 17 kmIsabela Municipio 17 kmMaricao Municipio 19 kmCamuy Municipio 19 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 3.3 (md)
Depth
19 km below the surface
Felt
no reports yet
Nearest
San Sebastián Municipio, 3 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3181 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

How big was it?

This earthquake released about 1.4 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 6.7 120,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 5,200× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,700× the energy of this one
  4. This earthquake M 3.3 about 1.4 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 3× 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.

Where

Epicentre 18.3313, -66.9985. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Sebastián Municipio, PR 3 km (2 mi) W of here earthquakes near San Sebastián Municipio
Moca Municipio, PR 10 km (6 mi) ESE of here earthquakes near Moca Municipio
Las Marías Municipio, PR 12 km (7 mi) N of here earthquakes near Las Marías Municipio
Añasco Municipio, PR 15 km (9 mi) ENE of here earthquakes near Añasco Municipio
Lares Municipio, PR 15 km (9 mi) WNW of here earthquakes near Lares Municipio
Quebradillas Municipio, PR 17 km (10 mi) SSW of here earthquakes near Quebradillas 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. 2.6 Mona Passage
  2. 2.2 2 km S of Guánica, Puerto Rico
  3. 2.7 21 km SW of Stella, Puerto Rico
  4. 1.6 0 km SE of Fuig, Puerto Rico
  5. 2.0 15 km SSW of Stella, Puerto Rico
  6. 2.7 11 km E of Maricao, Puerto Rico
  7. 1.7 2 km SE of Maria Antonia, Puerto Rico
  8. 2.3 3 km WNW of Santo Domingo, Puerto Rico
  9. 2.7 19 km NW of San Antonio, Puerto Rico
  10. 2.5 11 km WNW of Puerto Real, Puerto Rico
  11. 2.2 5 km NNW of Puerto Real, Puerto Rico
  12. 2.0 4 km W of Las Marías, Puerto Rico
  13. 2.1 4 km ESE of Las Marías, Puerto Rico
  14. 1.8 2 km SSW of Palmarejo, Puerto Rico
  15. 2.3 22 km W of Puerto Real, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.3 on 2017-10-14 — it released about 30 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

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