Paleogene Foredeep Basin Deposits of North-Central Cuba: A Record of Arc-Continent Collision between the Caribbean and North American Plates

Abstract

Paleogene deposits of north-central Cuba have been identified as a deformed foredeep basin, whose stratigraphy recorded very well the collision of the Bahamas—Proto-Caribbean realm (North American plate) with the Caribbean plate, a process that occurred since latest Cretaceous to early Late Eocene time. The debris incorporated in the foredeep basin has two provenance regions and four tectonostratigraphic sources, including: (1) the Caribbean Plate (1a = allochthonous Cretaceous arcs, 1b = serpentinite mélanges and ophiolites); (2) the North American plate (2a = Pre-Paleogene sedimentary rocks derived from the substrate of the foredeep basin, 2b = Cretaceous Bahamian carbonate platform rocks). Evaluation of the age, size, and volume of the debris demonstrate the formation of a forebulge within the Bahamas platform in response to the collision between the Caribbean and North American plates, and the northeastward migration of the axis of maximum subsidence of the foredeep basin since the Paleocene. By the early Late Eocene, structural NE-SW shortening ended in central Cuba, with uplift and deep erosion, followed by a quick transgression before the end of the Eocene. The resulting Upper Eocene sediments unconformably cover the deformed foredeep deposits and underlying rocks, finishing the formation of the North Cuba—Bahamas fold-and-thrust belt. Palinspastic reconstructions suggest that this belt accommodated nearly 1000 kilometers of shortening, during underthrusting of the Proto-Caribbean crust below the Caribbean Plate.