QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

135 km N of San Juan, Puerto Rico

· 61 km deep · released about 1.7 tons 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 3.4 (md)
Depth
61 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2459 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 1.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 99,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,100× the energy of this one
  4. This earthquake M 3.4 about 1.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 3.6× 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 19.6880, -65.9685. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 3.8 Puerto Rico region
  2. 3.6 121 km N of San Juan, Puerto Rico
  3. 3.8 117 km N of Brenas, Puerto Rico
  4. 3.7 134 km N of San Juan, Puerto Rico
  5. 3.5 113 km N of San Juan, Puerto Rico
  6. 3.3 108 km N of Suárez, Puerto Rico
  7. 3.9 151 km N of San Juan, Puerto Rico
  8. 3.4 103 km N of San Juan, Puerto Rico
  9. 3.6 124 km N of Brenas, Puerto Rico
  10. 3.0 Puerto Rico region
  11. 3.5 110 km N of Suárez, Puerto Rico
  12. 3.6 127 km N of Suárez, Puerto Rico
  13. 3.3 113 km NNE of San Juan, Puerto Rico
  14. 3.7 107 km N of Suárez, Puerto Rico
  15. 3.5 127 km N 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.4 on 2016-10-23 — it released about 35 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.