The stratigraphic and structural evolution of the Florida-Cuba-Bahamas collision zone has historically been highly generalized when incorporated into plate tectonic models. Recent integration of publicly accessible well, seismic, and geochemical data has led to a better understanding of the paleogeographic history and petroleum potential of the area. Structural deformation and lithologic units within the collision zone have been described previously but bear repeating here. The area can be partitioned into three distinct zones: · a southerly zone from southern to central Cuba, which can be characterized by arc and back-arc collapse features and is dominated by basic igneous rocks; · a central zone extending from central Cuba to the Florida-Cuba-Bahamas coastal zone, characterized by highly duplexed arc, fore-arc, and Bahamian passive margin rocks; and, · a northerly foreland zone located between Cuba and Florida and the Bahamas, characterized by longer wavelength, lower amplitude fault-bend folds, hanging-wall anticlines, and normal faults, involving only Bahamian passive margin rocks. Deformation within the collision zone continued until the Late Eocene and strongly influenced the hydrocarbon prospectivity of the region. Hydrocarbon exploration within the Cuba-Florida-Bahamas collision zone has largely been unsuccessful since the 1980s and recent deepwater drilling off the northern coast of Cuba has yielded only non-commercial shows or dry holes. Most of the plays in this region have been tested and have failed due to a lack of charge focus, poor trap integrity, or poor/non-commercial reservoir deliverability. A new play concept with significant volumetric and commercial potential is required in order to justify further exploration in the region. One prospective area that has yet to be evaluated adequately with modern seismic and drilling technology lies between the northeastern Cuban coast and the southern Great Bahamas Bank (Fig. 1). Hydrocarbon prospectivity in this area can best be evaluated via the critical assessment of standard play risk elements. Main petroleum systems elements include: · Reservoirs: Primary reservoirs consist of widespread, immature Upper Triassic to Lower Jurassic quartz-rich sandstones, which are oil and gas bearing in the Great Issac-1 and Bass Pumpkin Bay-1 wells; secondary reservoirs may be present in Upper Neocomian carbonates. · Sources: Three main sources include Lower Cretaceous (Neocomian) basinal limestones and oil generative marls; Upper Jurassic (Oxfordian-Tithonian) basinal limestones and oil generative shales; and Middle (?) Jurassic or older, likely light oil and wet gas generative, estuarine/lacustrine shales. · Charge Volume and Timing: Hydrocarbon charge to potential traps has likely been effective only in areas of good charge focus and documented top seals; expulsion has occurred primarily from below the collision zone and into both the pre-collision and post-collision portions of the foreland basin towards the north (Fig. 1). · Seals: Upper Jurassic Punta Alegre evaporites and Lower Cretaceous evaporites and shales provide effective regional seals. · Traps: Primary traps in the foreland include hanging wall anticlines and fault bend folds, sub-thrust fault traps, and domes over uplifted basement horsts.
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