This project involves a study of the Hellenic subduction system, one of several young subduction systems within the Mediterranean region that are characterized by extension of upper plate lithosphere and roll-back of the trench away from the over-riding plate. Such subduction systems are thought to be driven primarily by the presence of a negatively buoyant slab. The Hellenic subduction system exhibits large variations in subduction rate and in the density of subducted lithosphere, in space and in time, as slow subduction of continental lithosphere along the entire belt was replaced by rapid subduction of oceanic lithosphere along the southern portion of the subduction boundary at ~8 Ma. Thus it provides an excellent opportunity to quantify the relationships among slab density and geometry, subduction rate, deformation of upper plate lithosphere, and the dynamic interactions between the slab and the surrounding mantle.
Specifically, the PIs will carry out a multidisciplinary study consisting of geologic mapping, isotopic dating, paleomagnetic studies, passive seismic studies, and theoretical and analog modeling of subduction processes. Through better documentation of magnitudes, rates, timing and geometry of this subduction system, the PIs aim at a fundamental understanding of the dynamic processes that control subduction in the Hellenic system and the way in which these processes are expressed at the surface.
