Cenozoic tectonic history of the North America Caribbean plate boundary zone in western Cuba

Structural studies of well-dated Jurassic to lower Miocene rocks in western Cuba constrain the sequence of structural events affecting this oblique collisional zone between the late Cretaceous island are and the Jurassic-Cretaceous North America passive margin in the southeastern Gulf of Mexico and Straits of Florida. Results of detailed mapping and collection of fault slip data at 34 sites define a regionally consistent, five phase tectonic model for the period from the late Paleocene to the post-early Miocene. During the late Paleocene to the early Eocene, the Cuban island are collided with the North American passive margin (Bahamas Platform). Northwest-ward overthrusting during the collision defines tectonic phase I. A NNE-SSW compression concurrent with early Eocene left-lateral strike-slip faulting along the Pinar fault zone defines phase II. This result is consistent with structural mapping showing sinistral shear within the 065 degrees striking Pinar fault zone. An ENE-WSW to E-W compression defining phase III overprinted phase II faults in the lower Eocene and older rocks. Post-early Miocene normal faulting characterizes phase IV. Inversion of fault slip data indicates two contemporaneous directions of tension of 120 and 170. Strike-slip faults that overprint phase IV normal faults yield a 120 compression (phase V). The direction of compression associated with the arc/continent collision rotates clockwise from NW-SE in the late Paleocene/early Eocene (phase I), to NNE-SSW (phase II) and to ENE-WSW by the middle Eocene (phase III). The rotation in the compression direction occurred because the are turned toward an oceanic area in the present-day area of central and eastern Cuba. Progressive collision led to complete subduction of the remnant oceanic crust by middle to late Eocene time.