Document Type : Original Research Paper


Earth Sciences Faculty, Shahrood University of Technology, Shahrood, Iran


      Kuh- Shah granitoidic pluton is located in the NE part of 1:100000 geological map of Baft. Lithological composition of this pluton includes Alkali- feldspar granite, granite, granodiorite, quartzdiorite, diorite and gabbro. This pluton has been intruded in volcaniclastics  of Eocene age. On the variation diagrams the trends of major and trace elements of studied samples indicate the continuity of lithological compositional range of this pluton and they have been from differentiation of a basic (basaltic) magma. From the genetic classification point of view the studied granitoidic pluton is from I type granite and it belongs to magnetite series. Based on the geochemical features Kuh-Shah granitoidic pluton is metaluminous with high and medium potassic calc-alkaline nature. High amounts of LILE and low amount of HFSE on the spider diagrams show that the parental magma of these rocks have been enriched from trace elements and incompatible elements. Based on the tectonic setting discrimination diagrams, this pluton is belong to VAG type and therefore it has been resulted from subduction of neotethys oceanic crust beneath the central Iran continental crust.


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