Three-dimensional instantaneous mantle flow induced by subduction
نویسندگان
چکیده
[1] We conduct three-dimensional subduction experiments by a finite element approach to study flow around slabs, which are prescribed based on a transient stage of upper mantle subduction from a laboratory model. Instantaneous velocity field solutions are examined, focusing on the toroidal vs. poloidal components as a function of boundary conditions, plate width, and viscosity contrast between slab and mantle. We show how the slab-to-mantle viscosity ratio determines the strength of toroidal flow, and find that the toroidal flow component peaks for slab/mantle viscosity ratios 100, independent of slab width or geometry. Citation: Piromallo, C., T. W. Becker, F. Funiciello, and C. Faccenna (2006), Three-dimensional instantaneous mantle flow induced by subduction, Geophys. Res. Lett., 33, L08304, doi:10.1029/2005GL025390.
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