Cenozoic Evolution of Sedimentary Basins in the Isthmus of Panama
The Cenozoic evolution of sedimentary processes in the Isthmus of Panama has been influenced by three primary tectonic events, first arc perpendicular subduction with ‘normal’ (mantle wedge derived) arc magmatism (65 -9.5 Ma), second, the formation of the Panama Fracture Zone (9.5 -3 Ma), and third, Cocos ridge subduction and adakitic magmatism in western Panama (< 3 Ma). It is generally thought that during the Late Miocene Panama was comprised of a volcanic arc archipelago and that by the end of the Miocene it had merged into a single land mass. Yet the exact manner in which the Isthmus of Panama emerged and eventually closed, the exact tectonic motions that drove that closure and the evolution of sedimentary basins in response to tectonic change is not well understood. We use correlations of Miocene to Pliocene aged stratigraphic, paleocurrent, petrographic, and geochemical data from samples collected from across Panama to reconstruct the evolution of fluvial drainage networks and carbonate and siliciclastic basins evolving in response to the emerging Cenozoic Panama Cordillera. We in turn use this data together with paleobotanical data to constrain the timing and 3D geometry of uplift and subsidence in the Panama Block.