Geochemistry and petrogenesis of basaltic flows in the Nain-Dehshir ophiolites

Abstract

Diabases, pillow lavas and basaltic flows in the Nain-Dehshir ophiolites are marked with flat to slightly depleted pattern in REE chondrite-normalized diagram and are characterized by depletion in HFSE and enrichment in LILE. This geochemical behavior can be considered for lavas erupted in arc-related environments. Clinopyroxene in these rocks shows low content of TiO2 and resemble those found in island-arc tholeiites. These characteristics are consistent with back-arc formation during middle to upper Cretaceous, due to the oblique subduction of Neotethyan Ocean along the active continental margin of the central Iranian block.

Keywords


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