Fluid migration from subducting slab to mantle wedge and flux melting of peridotites recorded in the basal part of the Oman ophiolite

Abstract

Lherzolite, harzburgite and dunite forms layers in the basal part of the mantle section above metamorphic sole in Sumaini window of northern Fizh block of Oman ophiolite. Peridotite with Cr# of spinel between 0.48-0.56 is absent. As a result, peridotites are divided into two group: Cr# higher or lower than this range. Chondrite-normalized REE patterns of clinopyroxene show light REE depleted patterns. The peridotites with high Cr# spinel formed by flux melting of the peridotites with low Cr# spinel after fluid infiltration. The peridotites with high Cr# spinel may have acted as a route for fluid migration within mantle section.