Hispaniola—Earthquakes and Tectonics

6min 40s Novice Spanish

What does the historic record tell us about earthquakes in the area?

Hispaniola straddles four plates: the Caribbean Plate and the Gonâve, Hispaniola, and North Hispaniola microplates. It is caught in the crunch between the North American and Caribbean Plates. Hispaniola has had a long history of deadly earthquakes, including the most recent one near Port au Prince in 2010. North of Hispaniola the North American plate has a more difficult time subducting because the Bahamas Carbonate Platform with limestone reef deposits up to 6-km-thick have doubled the crustal thickness with more-buoyant material that resists subduction.

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Keypoints:

  • Hispaniola sits on 3 microplates and one major plate
  • The North American plate can't subduct easily because of the Bahamas carbonate platform that rides atop it.
  • The oblique collision causes strain partitioning on strike slip faults
  • Hispaniola is caught between two thrust faults
  • A M7.9 megathrust earthquake in 1946 created a tsunami caused 1,790 local fatalities, and traveled over 2000 miles 
  • Significan faults pass through or near major population centers

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