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A B S T R A C TAr/Ar ages determined on rocks and minerals from the Camagü ey area in central Cuba provide age constraints on events that accompanied the northward migration of Cuba into the Caribbean region and its subsequent collision with the Bahamas Bank. Whole-rock samples from the Camujiro and Piragua Formations, part of the Camagü ey volcanic sequence, yielded Ar/Ar ages of 74-72 Ma, distinctly younger than the 100-80-Ma ages indicated by fossils in interlayered sedimentary rocks. Syenite and granodiorite in the Camagü ey batholith, which cut these volcanic rocks, yield generally similar Ar/Ar ages of 75-72 Ma for hornblende, biotite, and feldspar. These ages are interpreted to reflect relatively rapid uplift and cooling of most of the volcanic-intrusive arc. Additional constraints on the timing of this uplift are provided by Ar/Ar ages of 71-75 Ma for rhyolite-rhyodacite domes of the La Sierra Formation and 52 Ma for andesitic basalt of La Mulata Formation, which appear to have been emplaced onto erosion surfaces that resulted from this uplift. An average cooling rate of about 13ЊC/Ma, which prevailed during formation of the arc between about 96 and 80 m.yr., increased to about 40ЊC/Ma after 80 Ma and ended with formation of a paleosurface at about 75 Ma or slightly afterward. The rapid uplift and denudation arc necessary to form a Late Cretaceous paleosurface on the volcanic-intrusive probably required an extensional tectonic environment, which could have been created during oblique convergence of the Greater Antilles arc with Yucatan as the arc migrated northward in Late Cretaceous time. Metamorphic rocks in the Escambray and Isle of Pines areas in western Cuba have ages similar to those indicated for uplift in the Camagü ey area, suggesting that extension and related Late Cretaceous paleosurfaces were widespread in the western Greater Antilles during its northward migration into the Caribbean region.

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