Studies of petrography, mineral chemistry and petrogenesis Sheyvardagh batholith (north of Ahar, East Azarbaijan)

Sheyvardagh granitoeid body is located in north of Ahar, East- Azarbaijan province, intruded into upper Cretaceous up to Eocene units, and caused the contact metamorphism and skarnificaion. This intrusive body in turn cut by veins and Quartz - applite dykes. The major minerals consist of quartz, plagioclase, k-feldspar, hornblende, biotite and clinopyroxene and pertite-antipertite, porphyry, granular and antirapakiwi textures are common in this unit. According to the mineral chemistry studies, the composition of biotite is located between stonite and sydrophilite poles and amphiboles are located in the range of magnesiohestingzite and magnesiohestingzit-hornblend. Clinopyroxenes are diopside and k-feldespar tends to sanidine pole and plagioclase lies in the range of oligoclase to andesine. Thermometry studies indicate the crystallization temperature of this body from 623°C to 750°C and emplacement pressure from 1.5 to 2.4 kb. The rocks are granodioritic and syenodioritic in composition and show has meta-aluminous nature. The producer magma of this body is shoshonitic and calc-alkaline in nature high-k properties. Al2O3, CaO, MgO, and TiO2 indicate descending pattern by increasing of SiO2. In the spider diagrams a distinct and positive anomaly of Ba, Rb, Th, La, Ta, Zr, Hf, Cs, U, Pb and Pr and negative anomalies of P, Nd, Lu and Mo were observed. The producer magma of this body has shoshonitic and high-k calc-alkaline nature and emplaced in a continental crust with high to medium thickness and influenced due to fractional crystallization or partial melting and crustal contamination. This body is emplaced in a post collisional, active continental margin setting.