Guillot, S., Schwartz, S., Hattori, K., Auzende, A. and Lardeaux, J. 2004. The Monviso ophiolitic Massif (Western Alps), a section through a serpentinite subduction channel. In: (eds.) Beltrando, M., Lister, G., Ganne, J., and Boullier, A., Evolution of the western Alps: insights from metamorphism, structural geology, tectonics and geochronology, Journal of the Virtual Explorer, Electronic Edition, ISSN 1441-8142, Volume 16, Paper 3.
The exhumation of subducted lithosphere requires a mechanically weak zone at the interface between the subduction plane and the rigid overlying mantle peridotites with a viscosity greater than 1020 Pa.s. At shallow depths (<40-50km) blueschists are exhumed in the accretionary wedge along the interface between the subducting plate and the overriding plate (Platt, 1993). At greater depth, serpentinites plays the role of a mechanically weak layer in cool continental subduction and acts as a lubricant, producing a return flow for the exhumation of eclogitic rocks. The close association of serpentinites and eclogites in the Monviso massif (Western Alps) allow the discussion of the concept of a subduction serpentinite channel. We propose that the Monviso ophiolitic massif corresponds to a section of a 50 km long serpentinite channel along which eclogitic blocks were exhumed between 60 and 45 Ma and ended when the European continental margin was involved in the southeast dipping subduction zone.
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