Role of dynamic grain boundary wetting in fluid circulation beneath volcanic arcs
نویسندگان
چکیده
[1] We report the influence of shear deformation on the microstructure of water-saturated olivine and clinopyroxene aggregates. Prior to deformation, the aqueous fluid was isolated in pockets along grain corners in the olivine-water aggregates, while it was interconnected by a network of grain-edge tubules in the clinopyroxene-water aggregate. During deformation of both types of aggregates, the aqueous fluid phase segregates into grain boundaries at an angle of 16 to the shear direction, inclined in a sense antithetic to the applied shear. Fluid-rich planes formed by such dynamic wetting of grain boundaries lead to the formation of high permeability paths in the matrix. In a deforming mantle, such high permeability paths will enhance the efficiency of aqueous fluid extraction from subducting slabs. Citation: Hier-Majumder, S., and D. L. Kohlstedt (2006), Role of dynamic grain boundary wetting in fluid circulation beneath volcanic arcs, Geophys. Res. Lett., 33, L08305, doi:10.1029/2006GL025716.
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