The PI will construct detailed three dimensional models of flow in subduction zone for comparison with seismic determi- nations of the flow, deformation and stress in subducted litho- spheric slabs. Adequate resolution will be obtained by solving for 3D flow in a limited region around the subduction zone (a few thousand kilometers) and superposing this small scale solution on the large scale flow resulting from global plate motions and large scale convection. Flow driven by tomograph- ically inferred density anomalies will be included. The analysis of the models will trace the flow of subducted material, deter- mine stress and deformation associated with deeep seismicity, and constrain mantle viscosity and structure. The models will allow a quantitative understanding of the dynamics and mechanics of subduction processes.
