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Late Jurassic Tectonics and Paleogeography (145 Ma).

Latest Jurassic (145 Ma)
  • Major plate reorganization -- change to sinistral motion of Farallon plate relative to North America causes Wrangellia to move southward
  • Complex series of events at SW margin of North America: Chortis and related terranes shift SE as Atlantic and Proto-Caribbean expand; transform fault and oblique rift systems developed along waning continental arc (McCoy-Bisbee; Mojave-Sonoran megashear); early Franciscan mélange formed farther outboard
  • Nutzotin Ocean between northern Wrangellia and North America remained open
  • Oblique convergence shut down much of Cordilleran arc
  • Late JurassicTectonic Map and Paleogeographic Map