A New Window into the Deep Mantle

Podiform Chromitite in the Luobusa Ophiolite, Southern Tibet

Abstract

 Podiform chromitites in Luobusa ophiolite yield a wide variety of unusual minerals, including UHP minerals (micro-diamond, coesite, moissanite), highly reduced minerals (native elements, alloys, carbides, and nitrides), and unusual silicate lamellae of diopside and coesite in chromites. These lines of evidence strongly suggest that podiform chromitites in the Luobusa ophiolite have a deep-mantle origin (probably more than 380 km deep). Podiform chromitite in Luobusa ophiolite might provide crucial clues for studies of the Earth's deep-mantle.