Limites convergentes: zonas de subduccion. Prismas de acrecion, arcos magmaticos

Plate tectonics Convergent boundaries

Plate tectonics Convergent boundaries Collision Subduction

Subduction modeling From 2D to 3D…

Subduction modeling About the plate tectonics 2D subduction model 3D subduction model Future works

Subduction modeling About the plate tectonics 2D subduction model 3D subduction model Future works

Subduction modeling About the plate tectonics 2D subduction model 3D subduction model Future works

First subduction model : 2D Rectangle domain Plate Upper mantle

First subduction model : 2D Lengths of the domain 3120 km 660 km Plate Upper mantle Lower mantle 100 km

First subduction model : 2D Boundary conditions No slip Plate Upper mantle Lower mantle

First subduction model : 2D Boundary conditions No slip Plate Upper mantle Lower mantle Free slip

First subduction model : 2D Boundary conditions No slip Plate Upper mantle Lower mantle Free slip

First subduction model : 2D Boundary conditions No slip Plate Upper mantle Lower mantle Free slip No slip

Governing equations Rayleigh-Taylor Instability: dense slab sinks into a less dense mantle … conservation of mass, incompressible medium … conservation of momentum … deviatoric stress tensorwith no energy equation

Rheology Viscous mantle Viscoplastic plate ViscousPlastic

The hardware: Horus supercomputer

2D subduction results

Lifecycle : flow reorganization

Necessity of the third dimension Importance of the mantle flow Real subductions have a limited lateral extent Interactions on the lateral edges of subduction zones

Subduction modeling About the plate tectonics 2D subduction model 3D subduction model Future works

3D subduction model Same governing equations Same tools used … only a different setup

3D subduction model upper mantle plate with subduction zone no upper plate Box size: big enough, for side walls to have little effect on subducting slab

The level set field subducting slab only subducting part of the plate is included in the FE domain use level set to define and track the subducting plate

Symmetry hypothesis assume symmetry: model only half of the domain free slip side boundary

Bottom boundary condition higher viscosity in LM and phase boundary hinder convection fixed bottom boundary

Slab boundary conditions plate fixed, to isolate effects of tearing and rollback fixed end free slip top boundary

Edge of the slab extreme case: free slip tear zone

Top boundary condition plate bottom fixed

Sides boundary conditions Freeslip on the sides

3D subduction results

Lifecycle of the subduction

Reorganization of the flow