Abstract: Tectonic Domains of Northern South America and the Southern Caribbean

E. D. Goodman, A. R. Green, T. J. Chisholm, C. J. Ando, I. O. Norton

The complex geology of this region reflects a tectonic history that includes Atlantic, Proto-Caribbean, Caribbean, Cocos, and Nazca plate interactions with 'stable' South American crust. Allochthonous rocks of different ages and affinities were diachronously emplaced along this broad, semi-circular margin. Plate motions were translated into complex vertical tectonics, including basin subsidence and inversion, overthrusting and fault reactivation. Therefore, we have reconstructed this history on a microplate scale to (1) understand the underpinnings of sedimentary basins here, (2) unravel their structural complexity, and (3) better predict the trap style within prospective subbasins. We have identified over sixty tectonic domains or provinces that comprise the region, based upon crusta type and age, tectonostratigraphy, neotectonics, interpretation of seismic reflection, gravity and magnetics data, and structural analysis and timing. Maps, regional transects, and seismic sections illustrate the boundaries between provinces and variability along strike. A west-to-east-younging family of provinces from Colombia to the Atlantic Ocean are defined by basement-involved normal faults active in flexed, foreland basin settings. Detached, mixed-style and thick-skinned fold-thrust belts are compared and contrasted. The complexity and uniqueness of the petroliferous basins here limit the utility of global analogs for evaluating their potential.

AAPG Search and Discovery Article #90951©1996 AAPG International Conference and Exhibition, Caracas, Venezuela