William R. Jamison¹, James A. Podruski¹
(1) Alturas Resources Ltd, Calgary, AB

Abstract: Tectonic history of Western Cuba

Cuba currently lies along the North American-Caribbean transform plate boundary, but the geology of this island also bears the history of several earlier, independent tectonic episodes. The earliest evident tectonic event is Middle Jurassic rifting associated with the opening of the Gulf of Mexico. Clastics and evaporites accumulated in the rift basin, and deep-seated faults formed at this time established a structural fabric that repeatedly influences the structural patterns of later tectonic events. The rift sequence strata are overlain by a drift sequence of Upper Jurassic to Upper Cretaceous platform to basinal carbonates.

During the Late Cretaceous, Caribbean Plate ophiolites and arc volcanics (Late Jurassic through Cretaceous age) were obducted over and sutured against the rift-drift rock units. Though clearly the result of a collisional event, the details of this tectonic episode remains enigmatic and controversial.

In latest Cretaceous time, numerous successor basins were created through reactivated movement on deep-seated faults in a strike-slip to transtensional setting. Pronounced variations in clast/grain size and composition reflect a large variation in structural relief and restricted sediment movement between individual basins. These basins continued to develop and receive sediments until the early Eocene.

From early Eocene through the Miocene, or later, the region uniformly and slowly subsided, with continuous carbonate deposition or build-up. Folding and thrusting, and probable salt diapirism, associated with post-Miocene transpression is responsible for most of the current physical relief on the island, and for the creation of many or most of the existing structural traps.

AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana