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Journal of Geophysical Research, 1997, vol. 102(B5), pp. 10,055-10,082.
By M.B. Gordon, P. Mann, D. C´a;ceres, and R. Flores
Abstract.
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 arc and the Jurassic-Cretaceous Notth 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 lO the early Eocene, the Cuban island arc collided with the North
American passive margin (Bahamas Plalform). 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¡ 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 b, to NNE-SSW (phase II) and to ENE-WSW by the middle Eocene (phase III). The
rotation in the compression direction occurred because the arc fumed 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.