LAUSR

AbstractThe north–south-trending Tobago-Barbados ridge (TBR) extends 250 km from its southern end at the island of Tobago to its northern end at the island of Barbados. On Tobago, exposed metasedimentary and metaigneous rocks have been identified as fragments of a Mesozoic primitive island arc, whereas on Barbados, exposed sedimentary rocks record Paleogene development of the Barbados accretionary prism (BAP). We integrate gravity data with seismic refraction data, well constraints, and seismic reflection data to improve our understanding of the TBR’s crustal structure, uplift mechanism, along-strike compositional variations in the crust, and tectonic origin. Three 2D gravity models suggest that the TBR is underlain by a “pop-up” crustal block uplifted in the trench between the overriding Caribbean plate and the westwardly subducting South American plate. At approximately 11.75° N, the character of the TBR changes over a distance of 60 km from a symmetrical and more elevated, crystalline, thrust fault-bou...