QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

6 km NE of San Sebastián, Puerto Rico

· 17 km deep · released about 15 lb of TNT

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10 km30 km60 km120 km N San Sebastián Municipio 6 kmQuebradillas Municipio 10 kmCamuy Municipio 12 kmIsabela Municipio 13 kmMoca Municipio 13 kmLares Municipio 15 kmLas Marías Municipio 17 kmHatillo Municipio 18 kmAñasco Municipio 21 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 1.8 (md)
Depth
17 km below the surface
Felt
no reports yet
Nearest
San Sebastián Municipio, 6 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2577 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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.

Where

Epicentre 18.3815, -66.9563. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Sebastián Municipio, PR 6 km (4 mi) NNE of here earthquakes near San Sebastián Municipio
Quebradillas Municipio, PR 10 km (6 mi) SSW of here earthquakes near Quebradillas Municipio
Camuy Municipio, PR 12 km (8 mi) SW of here earthquakes near Camuy Municipio
Isabela Municipio, PR 13 km (8 mi) SSE of here earthquakes near Isabela Municipio
Moca Municipio, PR 13 km (8 mi) E of here earthquakes near Moca Municipio
Lares Municipio, PR 15 km (9 mi) NW of here earthquakes near Lares Municipio

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

Aftershocks so far

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

  1. 2.5 4 km SSE of Cacao, Puerto Rico
  2. 2.3 28 km NW of San Antonio, Puerto Rico
  3. 1.9 3 km SW of San Sebastián, Puerto Rico
  4. 2.7 36 km NNE of Isabela, Puerto Rico
  5. 2.6 24 km N of San Antonio, Puerto Rico
  6. 2.3 25 km N of Isabela, Puerto Rico
  7. 1.5 2 km E of Mayagüez, Puerto Rico
  8. 2.4 31 km NNW of San Antonio, Puerto Rico
  9. 2.9 28 km N of Isabela, Puerto Rico
  10. 2.1 11 km NNE of Garrochales, Puerto Rico
  11. 2.1 2 km NE of Jayuya, Puerto Rico
  12. 2.5 9 km N of Isabela, Puerto Rico
  13. 1.8 8 km ENE of Maricao, Puerto Rico
  14. 1.9 3 km SSW of Maricao, Puerto Rico
  15. 2.2 18 km N of Hatillo, 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 5,600 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.