Seyedeh Azam Mousavi; Ashraf Torkian
Abstract
The studied intrusive bodies are located in the N-Sanandaj-Sirjan Zone and Kurdistan Province. In these masses, the host rocks include granite, granodiorite and monzonite, and the enclaves ...
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The studied intrusive bodies are located in the N-Sanandaj-Sirjan Zone and Kurdistan Province. In these masses, the host rocks include granite, granodiorite and monzonite, and the enclaves also are dioritic and gabbroic in composition. The (MMEs) are scattered in rounded and elliptical shapes in the host rocks and generally they have a sharp contact with their host and are composed of igneous minerals.The presence of mafic fine-grained enclaves with evidence of disequilibrium textures such as feldspar with poikylitic texture, presence of mafic masses and needle apatites, small blades-shaped plagioclase within large plagioclase or presence of two generations of plagioclase, and zoning all confirm magmatic mingling/ mixing processes. Field relationships, petrological and geochemical studies show that the magma of this complex is I-type, metaluminous and belonging to calc-alkaline series. The enrichment of the studied enclaves in Co, Ni, Cr and Heavy Rare Earth Elements (HREEs), display that these rocks are globules of mafic magmas mingling to felsic type. Also, the relatively high content of Mg# (34-48) suggests that the host rocks were formed by mixing mantle derived mafic magma with felsic magma of the crust. In addition to the mentioned geochemical characteristics, the enclaves are depleted in LREE and LILE and enriched in titanium, so it seems to have originated from two different magmas and only due to the magma mixing/ mingling process are nextby to each other.