Principal features of Cuban geology

The Cuban orthogeosyncline consists, from north to south, of a platform region (Bahamas parageosyncline), a foredeep or miogeosyncline (Old Bahamas Channel, Cayo Coco, and Remedios facies-structural zones), a marginal elevation or welt (Las Villas facies-structural zone), and a eugeosyncline. The latter includes several intrageosynclinal depressions, of which the Zaza facies-structural belt is the most extensive, and some intrageosynclinal positive areas. The history of the orthogeosyncline lasted from Early Jurassic to relatively recent time. The tectonic history may be divided into three gross cycles: Lower-Middle Jurassic; Upper Jurassic-Paleogene; and Paleogene-Neogene. Each gross cycle is divisible into structural levels or subcycles. In general, deformation is most intense in the oldest structural level and least intense in the youngest. Continental drift of Cuba from South America, as postulated by Corral, does not seem likely Instead, an origin more like that which is explained by the tectogene hypothesis seems probable. However, the belt of negative gravity anomalies that underlies north Cuba coincides with the position of the marginal elevation, and not with the positions of the eugeosyncline or miogeosyncline. Basically, the island of Cuba is part of a more extensive, but inactive, orthogeosyncline or island arc that extends the length of the Greater Antilles. The shape of this island arc probably was determined by the presence of a large island that occupied the present position of the Caribbean Sea. This island subsequently may have been subjected to the processes of basification, or conversion to oceanic crust. If this is true, Cuba now appears to be an intrageanticlinal structure within a new, modern Antillean geosyncline that includes the Greater Antillean arc and the newly formed oceanic areas nearby.