Presence of Stratigraphic Traps in the Back Arc Basins of the Southern Shelf of Cuba: ABSTRACT

Abstract

ABSTRACT For the last ten years the southern shelf of Cuba has been theobject of seismic investigations, mainly in the Ana Maria and Guacanayabo areas. More than 4000 km of seismic lines with 3000% have been shot. These seismic surveys have confirmed the following geological events: Presence of back arc extensional basins as a result of the ocean/ocean subduction. These basins have formed since Middle Cretaceous. Presence of sedimentary sequences with thickness changes of between 3.0-7.0 km. Predominance of an extensional regime since Middle Cretaceous with subsidence, accommodation and extension of the rocks. Development of stratigraphic traps, mainly associated with reef facies and slope fans of Late Cretaceous-Early Tertiary. These traps can reach hundreds of square kilometers. They have very clear dynamic expression in the seismic section and usually form anomaly zones. Over these seismic anomalies some reverberation can be observed which could be related to hydrocarbon flows. The depth of the traps changes between 1.5-3.5 km. More than thirty have been localized. Probably a wrench tectonic system has been present in these basins since Middle Eocene. Oil and gas seepage as well as seal sequences are present in some wells. According to their origin and evolution they can be similar to the great oil basins of Venezuela and Colombia. End_of_Record - Last_Page 478-------