Tectonic Setting of Metabasites of the Neo-Tethyan Oceanic Remains in Sanandaj-Sirjan Structural Zone West of Isfahan, Central Iran

Subject Areas : Mineralogy

Ali-Khan  Nasr-Esfahani ¹ (Geology department, Islamic Azad University, Khorasgan (Isfahan) Branch, Iran.)

Received: 2016-05-31 Accepted : 2016-05-31 Published : 2012-09-22

Keywords: Metabasite, Neo-Tethyan, Petrology, Sanandaj-Sirjan,

Abstract :

The study area is located in the western portion of Isfahan, in Shahrekord-Dehsard Terrene. This area is part of the Sanandaj- Sirjan structural Zone. In this area, metamorphosed igneous outcrops contain greenschist and metabasite rocks. These rocks have metamorphed into greenschist facies and belong to the Triassic-Jurassic age. The etabasite is mainly composed of plagioclase, amphibole, epidote and chlorite. Geochemical data shows that the parent rocks are of basalt to andesitic basalt composition with sub alkaline and tholeiitic trends. In the REE and trace elements spider diagrams, these are similar to MORB and adapted with E-MORB. These results indicate a metabasite enerated back arc basin volcanic subduction environment. The Metabasite in Sahrekord - Dehsard terrene shows remnants of a Neo-Tethyan oceanic lithosphere with a back arc basin environment that was subducted and uplifted to the surface.