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Jurassic and Cretaceous Geological History of Cuba

The Mesozoic rocks of Cuba are a key element in reconstructing the geological history of the Mesoamerican (Gulf of Mexico and the Caribbean) area. Four different Jurassic-Cretaceous sections are recorded in Cuba, including three from tectonostratigraphic terranes. From north to south they include the following: (1) a portion of the Mesozoic passive margin of North America, with outstanding zonality, especially in the Middle Cretaceous of central Cuba; (2) the Northern Ophiolitic Belt, also with Upper Jurassic-Lower Cretaceous rocks, which is a huge melange; all members of the ophiolitic suite are tectonically mingled along the northern part of Cuba; (3) the Volcanic Arc Terrane, mainly composed of Cretaceous volcanics, with older, primarily tholeiitic lavas (Aptian-Albian) and younger (Cenomanian-Campanian) calc-alkaline pyroclastics and lavas, with many sedimentary interbeds; Albian-Cenomanian deposits with a few volcanics separate both sequences, and an Upper Jurassic-Neocomian amphibolitic basement of the volcanic arc is present in some places; and (4) the Southern Metamorphic Terranes that contain rocks of a Mesozoic passive margin that experienced several metamorphic episodes during the Cretaceous. The welding of these terranes occurred during the Cretaceous, and ended in the late Campanian and Maastrichtian. In the south, the volcanic terrane was emplaced upon the Southern Metamorphic Terranes, while in the north the volcanics and ophiolites were thrust over the Mesozoic margin of North America. In western Cuba, the beds are strongly deformed and thrust to the north or northwest. Nappes also are present in north-central Cuba, but an essentially Bahamian platform stratigraphy is present. Although the passive paleomargin of North America was deformed in the latest Cretaceous, this event is masked by the early Tertiary Cuban orogeny. It is suggested that the Jurassic stratigraphy of the Southern Metamorphic Terranes shares features with the southern North American passive margin in western Cuba. The position of the Southern Metamorphic Terranes south of the ophiolite and arc terrane therefore does not support the idea of a Pacific origin for the Cretaceous island arcs of the Greater Antilles, but instead suggests that a proto-Caribbean genesis is more plausible.