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Pillow lavas are one of the important rock units of Nain ophiolite. Rock forming minerals of Nain ophiolite pillow lavas are chloritized olivine, plagioclase, clinopyroxene (augite), Cr-spinel, magnetite, amphibole, chlorite, pumpellyite, epidote, prehnite and calcite. Whole rock geochemical analyses and composition of clinopyroxenes and chromian spinels of these rocks indicate that they are similar to mid-ocean ridge basalts. These lavas are basalt to andesite in composition and produced by high degree of partial melting of a depleted mantle lherzolite. According to their field studies, petrography, mineral and whole rock geochemistry, they have undergone sub-sea floor metamorphism and changed to spilite. Application of clinopyroxene thermometry shows that they have formed at 1058 to 1170 ^OC.

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The ophiolitic complex of Sahneh-Harsin is composed of rock units such as gabbro, basalt, diabasic dikes, diorite and plagiogranite. The geochemical studies show that primitive magma has been sub-alkaline tholeiitic Mg-rich and K-poor. These data show enrichment of light rare earth elements (LREE) and depletion of heavy rare earth (HREE). The ratio of NbTa in the basalts is between 16.19 and 18.88; therefore these high amounts indicate the magma derived from the contaminated mantle. Lithological and geochemical studies show that there are genetic connections between the rocks and their origin from the same magma. Magmatic contamination and differentiation had important role in evolving of rocks and they formed during melting of more than 16% of a garnet peridotite. Petrogenesis of pillow lavas shows they are of MORB type; based on spider diagarms this complex is formed from a oceanic tholeiitic magma of EMORB Enriched (MORB).

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Sabzevar ophiolitic pillow lavas contain variolitic, porphyritic with microlitic matrix, intersertal and amygdaloidal textures and include plagioclase, clinopyroxene (augite-diopside), olivine, amphibole (magnesiohastingsite) and opaque minerals. The chemical composition of clinopyroxenes show a calc-alkaline magmatic series and a tectonic environment within plate alkaline basalts. Geochemically, these rocks are divided into two groups. Group 1 is basically calc-alkaline andesite with low TiO₂ and group 2 is alkali basalt with high TiO₂. N-MORB normalized trace elements diagram shows that group 1 is enriched in Th, U, La and depletion in Ta, Nb, Ti and group 2 is enriched in Th, Ta and Nb. Calc-alkaline rocks have produced in a subducted tectonic environment by a continental crust and erupted southwards on the Turan plate. In contrast, alkaline rocks formed within plate oceanic and then tectonically accreted in the forearc setting.