Melt/mantle mixing produces podiform chromite deposits in ophiolites: Implications of Re–Os systematics in the Dongqiao Neo-tethyan ophiolite, northern Tibet

Podiform chromite deposits occur in the mantle sequences of many ophiolites that were formed in supra-subduction zone (SSZ) settings. We have measured the Re–Os isotopic compositions of the major chromite deposits and associated mantle peridotites of the Dongqiao Ophiolite in the Bangong–Nujiang suture, Tibet, to investigate the petrogenesis of these rocks and their genetic relationships.