Lesser Antilles—Earthquakes and Tectonics

8min 52s Novice

The islands of the Lesser Antilles are formed by the subduction of the North and South American Plates (referred here as the "Atlantic plate") beneath the Caribbean Plate. Convergent plate margins, where two oceanic plates are colliding, often produce megathrust boundary earthquakes. Those are curiously absent along the Lesser Antilles trench.

Much has been learned in the past decades about the affect of the subducting plate. 

Keypoints:

  • The islands of the Lesser Antilles, from Anguilla to Trinidad, are home to 3.2 million people.
  • Atlantic Ocean lithosphere subducts beneath the Caribbean Plate at the Lesser Antilles Trench producing earthquakes that increase in depth from east to west across the subduction zone.
  • Since 1970, there have been only 19  earthquake >M6 along the 900-km length of the subduction zone.
  • The largest recorded earthquake, the 1972 M7.2 Antigua earthquake, was in the shallow forearc crust of the subducting plate.

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