Major hydrocarbon plays in the Mexican sector of the Gulf of Mexico, the Caribbean, and northern South America

Abstract

The Gulf of Mexico (GOM), Caribbean, and northern South America form a geologic province (Figure 1) that is strategically located to provide major sources of conventional and non-conventional hydrocarbons for western hemisphere markets (Figure 2). Present production defines two separate and geologically distinct regions of giant oil and gas fields in the US and Mexican sectors of the Gulf of Mexico and in Colombia, Venezuela, and Trinidad and Tobago in northern South America (Figure 2). These two regions of major production are separated by a vast area of marginal or absent production in the Caribbean region extending from northern South America to Cuba and from Central America to the Lesser Antilles (Figure 2). The Caribbean region formed in an oceanic setting in the eastern Pacific and was transported into its present position over the last 80 million years along complex plate boundary systems some of which have remained active to the present-day (Figure 1). The oceanic-derived geology of the Caribbean differs completely from the passive margin geology of the Gulf of Mexico and northern South America. Key points made using plate tectonic reconstructions and previously published work by Mann and Escalona (2006; 2011) include: 1) importance of early rifting and restricted circulation between North and South America to explain the distribution of highquality late Jurassic source rocks in the GOM and northern South America; 2) tectonic stages in the formation of the GOM and plays related to its rift phase, passive margin I phase, Laramide orogeny phase, passive margin II phase, and active margin phase; 3) control of the colliding Cuban arc on formation of a foreland basin in the southeastern GOM and deformation along the edge of the Bahama carbonate platform; 4) oblique collisional history of the Great Arc of the Caribbean along the northern margin of South America including the formation of a hydrocarbon-rich foreland basin on continental crust; 5) influence of the Miocene to recent Panama arc collision on the hydrocarbon potential of preexisting basins in northwestern South America; and 6) effects of strike-slip faults of the circum-Caribbean on hydrocarbon potential. Passive margins are likely the place where more hydrocarbons will be found because giant hydrocarbon deposits require a combination of time, burial and a minimal amount of ongoing tectonic activity that can disrupt the reservoir and allow hydrocarbons to leak to the surface. The dense cluster of hydrocarbons in the GOM reflects its passive margin pedigree and its tectonic setting well within the stable North American plate. The Caribbean plate has potential for hydrocarbons but its sources are of mainly of Cenozoic age and it lacks the older, world class late Jurassic source rocks that are commonly found in the passive margin settings. It is apparent from Figure 2 that the GOM has tremendous remaining potential. If the GOM is considered as a clock face, systematic exploration from shelf to deep basin has only been carried out in the offshore areas of the US states of Texas and Louisiana between 9 and 1 o’clock. The remaining areas of the clock face from 1 to 9 o’clock in Alabama, Florida, Cuba and Mexico await exploration on the slope and deep water. All these unproductive areas of the GOM are likely to benefit from the widespread distribution of high-quality late Jurassic source rocks that