QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

129 km N of Isabela, Puerto Rico

· 38 km deep · released about 1,500 lb of TNT

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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 3.1 (md)
Depth
38 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3116 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 1,500 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 230,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 10,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,200× the energy of this one
  4. This earthquake M 3.1 about 1,500 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.6× 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 19.6743, -66.9796. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 3.0 144 km N of Tierras Nuevas Poniente, Puerto Rico
  2. 2.8 94 km N of Isabela, Puerto Rico
  3. 3.3 135 km N of Carrizales, Puerto Rico
  4. 3.0 81 km N of Isabela, Puerto Rico
  5. 2.9 107 km NNW of San Antonio, Puerto Rico
  6. 3.0 92 km N of Isabela, Puerto Rico
  7. 3.3 108 km NNW of San Antonio, Puerto Rico
  8. 3.2 118 km N of Isabela, Puerto Rico
  9. 3.4 123 km N of Hatillo, Puerto Rico
  10. 3.1 102 km N of San Antonio, Puerto Rico
  11. 2.8 89 km N of Isabela, Puerto Rico
  12. 3.0 91 km N of Isabela, Puerto Rico
  13. 3.1 127 km N of Isabela, Puerto Rico
  14. 3.1 88 km N of Isabela, Puerto Rico
  15. 3.1 100 km N of Isabela, 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.