Lithospheric Structure and Supracrustal Hydrocarbon Systems, Offshore Eastern Trinidad
Stefan S. Boettcher, J. L. Jackson, M. J. Quinn, J. E. Neal, 2003. "Lithospheric Structure and Supracrustal Hydrocarbon Systems, Offshore Eastern Trinidad", The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon Habitats, Basin Formation and Plate Tectonics, Claudio Bartolini, Richard T. Buffler, Jon F. Blickwede
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To facilitate an evaluation of hydrocarbon systems elements in offshore eastern Trinidad, we generated regional cross sections and a 1000-km-long conceptual, lithospheric-scale cross section from the Aves ridge to the Demerara plateau. The sectionsare based on interpretation of 2-D and 3-D seismic data, gravity and magnetics surveys, and published literature. Our results indicate that convergent-margin tectonism and rapid sedimentation first impacted the deep-water area of offshore eastern Trinidad in the latest Miocene. As much as 12 km of post-middle Miocene sediments are present south and east of the Caribbean–South American Plate boundary zone in the Columbus basin foredeep. The basin formed in response to subduction, tectonic loading, and progradation of the Orinoco delta. Well-imaged, northeast-trending buckle folds occur above the detachment fault(s) and are an important trap-forming element in the deep-water area. Deep-penetrating, active growth faults are the principal hydrocarbon migration pathways on the continental shelf but are absent in the deep-water exploration area. Seismic quality diminishes rapidly to the north of 11°N latitude, in an area where highly irregular sea-floor topography marks active deformation and dewatering in the internal part of the Barbados accretionary complex.
We propose that the change in crustal type across the Mesozoic passive margin of northern South America controls the style and magnitude of strain above the main décollement associated with the Cenozoic convergent margin. Contractional structures developed in Trinidad when continental lithosphere of the South American plate impingedon the subduction zone atthe leading edge of the Caribbean plate. The positive buoyancy of continental lithosphere resists subduction, resulting in more earthquakes, a fold and thrust belt from eastern Venezuela to offshore eastern Trinidad with as much as 100-km shortening, and the southern limit of the Lesser Antilles volcanic arc. The transition to oceanic crust in offshore eastern Trinidad marks a change in tectonic environment from continental fold and thrust belt to accretionary prism above subducting oceanic crust.
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The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon Habitats, Basin Formation and Plate Tectonics
The Circum-Gulf of Mexico and the Caribbean has long been one of the world's most important petroleum provinces, as well as one of the world's most geologically complex regions. These two characteristics have resulted in an extensive amount of ongoing research by both industry and academia. AAPG Memoir 79, The Circum-Gulf of Mexico and the Caribbean, is the first volume in more than a decade to document such a wide range of research on the geology of this vast area. Of the total 44 papers, roughly two-thirds pertain to the Gulf of Mexico, with an emphasis on the Mexican portion of the basin, and to the petroliferous areas of the southern Caribbean, including Colombia, Venezuela, Cuba, and Trinidad and Tobago. The remaining papers relate to the Antilles and Central America, as well as a series of papers that address region-wide topics such as plate tectonic evolution. A significant number of papers were contributed by authors from national oil companies and universities from within the region.