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Mantle wedge deformation by subducting and rotating slab and its possible implication


We have constructed a simple model of the deformation of the mantle wedge caused by the subducting and rotating slab based on corner flow model. By applying this model to the geological settings of the Somuncura plateau volcanic region, northern Patagonia, which is located far from the volcanic front, we constrain the mechanical aspect of the hypothesis that the volcanisms of the Somuncura region are triggered by the dehydration-induced melting of the up-warped transition zone which may contain more water than other regions do. Assuming that the water concentrates in the transition zone under the Somuncura plateau, we find that the above scenario may be possible, if the speed of the subducting slab is less than 2 cm/yr or the dip angle changes significantly (50 degrees within 8 Myr).


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Correspondence to S. Honda.

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Honda, S., Orihashi, Y., Mibe, K. et al. Mantle wedge deformation by subducting and rotating slab and its possible implication. Earth Planet Sp 58, 1087–1092 (2006).

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Key words

  • Mantle wedge
  • rotating slab
  • volcanism
  • Somuncura
  • transition zone
  • water