Mineralogy and Geochemistry of Titaniferous Gabbros of Ophiolitic Fanouj Zone (Sistan & Baluchestan, Iran)

Ophiolite complex in the west of Fanuj is 200 Km south west of Iranshahr in Sistan and Baluchestan province. This ophiolite complex lies in the uplift zone of the oceanic crust of Oman between Makran and Fanuj faults. Ophiolite of the west part of Fanuj is consisted of three parts including gabbro, diabase dikes and small quantity microdiorite masses. Ilmenite is the main mineral of titanium which along with magnetite has been formed independently or inter-crystalline way after crystallization of plagioclase, pyroxene and often along with amphibole in gabbro rocks. The formation of the broad gabbro masses which is associated with plagioclase and pyroxene crystallization in High Oxygen fugacity condition formed a fluid rich in iron and titanium during the formation of ferro gabbro rocks as the main host of the ilminite reserves. Gradual crystallization process and decrease in compatible elements such as Cr, Ni, Mg and increase in incompatible elements such as Mn، Na، Ti from the bottom to the upper parts of ophilite complex shows that the formation of the complex has been occurred through the process of crystal fractionation from a tholeiitic magma which is rich in titanium.