CaAl-silicates : An Important Sr Container in Subducted Slab

Abstract

SrO contents of epidote group minerals and lawsonite are 1-4 order magnitude higher than those of coexisting major constituent minerals in eclogitic rocks. Epidote group minerals contain >70 % of the whole-rock SrO. CaAl-hydrous silicates are regarded as the most important Sr reservoirs in subducted slab and are capable of transporting Sr deep into the mantle. Their breakdown would contribute significantly to the Sr budget of the mantle and to its Sr isotopic evolution.