Conférence GM & ED Gaïa :

Deformation and hydration state of the mantle wedge corner in subduction zones

archive articles

presented by Ikuko WADA (University of Minnesota, USA)

at 11:00 amphi 23.01 campus Triolet – Université de Montpellier

Participer à la conférence Zoom (ID de réunion : 912 0018 5245)

The physical state of the mantle wedge corner in subduction zones affects a range of important processes, such as megathrust earthquakes, tremor and slow slip, and deformation of the overriding forearc lithosphere. The deformation condition of the mantle wedge corner has been inferred from shear wave splitting (SWS) observations, but their interpretation depends on the crystal-preferred orientation (CPO) of minerals in the wedge corner. Further, its physical properties are impacted by the hydration of the mantle rock peridotite into serpentinite. Serpentinization causes density and strength reduction and volume increase of the mantle rock, and its spatial extent depends on fracture networks, which in turn depend on tectonic and reaction-induced stresses. Our project aims to provide a better understanding of the deformation and serpentinization of the mantle wedge corner by addressing (1) the CPO patterns in the mantle wedge corner and their impact on SWS and (2) the effects of tectonic and reaction-induced stresses on fracture formation and the spatial extent of serpentinization in the mantle wedge corner.


B.Sc. and Ph.D. from the University of Victoria, Canada; Postdoc at the Woods Hole Oceanographic Institution, MA, and Virginia Tech, VA, USA; Assistant professor at Tohoku University, Japan; Currently Associate professor at the University of Minnesota, USA. The main research field is subduction zone geodynamics. Research topics include heat transfer, mantle flow, lithospheric deformation, and fluid migration.