Deformation of fine-grained synthetic peridotite under wet conditions

Abstract

Fine-grained hydrated peridotite mylonites have been proposed to play an important role in controlling the strength of the continental lithosphere during rifting. For this reason, the deformation behaviour of wet fine-grained forsterite and forsterite-enstatite materials and the underlying deformation mechanisms, form a subject of considerable interest in structural geology and tectonophysics. In addition, the deformation of polycrystalline forsterite-rich material is of fundamental interest for understanding the behaviour of upper-mantle materials in general. This thesis reports an experimental, materials science oriented investigation aimed at providing a better understanding of the deformation behaviour ofwet fine-grained olivine and olivine-enstatite material, under conditions favouring grain size sensitive defomlation processes.