Chromitite potential in mantle peridotites of the Jandaq ophiolite (central Iran)

Abstract

Mantle peridotite (lherzolite) is one of the most important rock units of the Jandaq ophiolite (central Iran). This ophiolite suffered numerous phases of metamorphism, and is covered by Paleozoic schist and marble metamorphic rocks. Metamorphic minerals found are olivine, tremolite, orthopyroxene, talc, anthophyllite, chlorite, serpentine and magnetite. Clinopyroxene and chromian spinel, the most resistant minerals against metamorphism and alteration, are relicts of the primary igneous mineralogy. One of the most important characteristics of the mantle peridotites in Jandaq ophiolites is the absence of chromitite, due to the low Cr- and high Al-nature of these mantle rocks, as well as non-extensive mantle partial melting during continual production of ascending melt. The Jandaq peridotite belongs to the LOT-type, and has no chromitite potential.