QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9ml

74 km NNW of San Antonio, Puerto Rico

· 27 km deep · released about 11 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Aguadilla Municipio 74 kmIsabela Municipio 79 kmQuebradillas Municipio 84 kmAguada Municipio 85 kmMoca Municipio 87 kmRincón Municipio 88 kmCamuy Municipio 90 kmHatillo Municipio 94 kmAñasco Municipio 96 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 3.9 (ml)
Depth
27 km below the surface
Felt
6 reports · strongest reported intensity III
Nearest
Aguadilla Municipio, 74 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2451 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 6 people have reported feeling it to USGS.

How big was it?

This earthquake released about 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 16,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 710× the energy of this one
  3. Magna, Utah 2020 M 5.7 500× the energy of this one
  4. This earthquake M 3.9 about 11 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 22× 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 19.1298, -67.3155. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Aguadilla Municipio, PR 74 km (46 mi) NNW of here earthquakes near Aguadilla Municipio
Isabela Municipio, PR 79 km (49 mi) NNW of here earthquakes near Isabela Municipio
Quebradillas Municipio, PR 84 km (52 mi) NNW of here earthquakes near Quebradillas Municipio
Aguada Municipio, PR 85 km (53 mi) N of here earthquakes near Aguada Municipio
Moca Municipio, PR 87 km (54 mi) NNW of here earthquakes near Moca Municipio
Rincón Municipio, PR 88 km (55 mi) N of here earthquakes near Rincón Municipio

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

Aftershocks so far

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

  1. 2.5 61 km NW of San Antonio, Puerto Rico
  2. 3.1 82 km NNW of San Antonio, Puerto Rico
  3. 2.3 36 km NNW of San Antonio, Puerto Rico
  4. 2.7 64 km N of Isabela, Puerto Rico
  5. 3.0 95 km NNW of San Antonio, Puerto Rico
  6. 3.6 75 km NNW of San Antonio, Puerto Rico
  7. 2.5 86 km NNW of San Antonio, Puerto Rico
  8. 2.0 107 km NW of San Antonio, Puerto Rico
  9. 3.1 57 km N of San Antonio, Puerto Rico
  10. 2.6 66 km N of San Antonio, Puerto Rico
  11. 2.9 Mona Passage
  12. 2.7 71 km N of Isabela, Puerto Rico
  13. 3.0 67 km N of San Antonio, Puerto Rico
  14. 2.9 60 km N of San Antonio, Puerto Rico
  15. 2.6 89 km NNW of San Antonio, 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 6.0 on 2019-09-24 — it released about 1,400 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.