3D GEODYNAMIC MODELS OF SLAB DRIVEN MANTLE FLOW BENEATH THE CARIBBEAN PLATE

Continued research into the processes governing subduction has expanded the classical view of two-dimensional corner flow to a slab driven flow that can be quite complex. To further examine this process and explore the nature of slab-driven mantle flow pathways, we present results from three-dimensional geodynamic models of the entire Caribbean system. The model configuration is based on a 3D integration of geologic and geophysical observations from the region, and is the most detailed and highest resolution 3D model of the modern Caribbean plate system. The model set-up includes the entire Cocos plate, the northern Nazca plate, the overriding plate lithosphere, and underlying mantle. We examine the effect of a continuous Cocos-Nazca slab versus the introduction of the Cocos-Nazca slab window on the mantle flow field beneath the Caribbean plate. The results provide a 3D solid-state mantle flow framework into which slab edge driven decompression melting and geochemical transport can be interpreted. In addition, the 3D models give insights into how a regional tectonic configuration can affect large-scale mantle flow.