Evaluating the origin and mode of formation of serpentine-talc-clinochlore mineral assemblages in Gol-Gohar Fe ore deposit, Sirjan



The Gol-Gohar Fe ore deposit is located at 55 Km SW Sirjan of Sanandaj-Sirjan structural zone. The host rock for ore deposit is Paleozoic Gol-Gohar metamorphic complex which consists of amphibolite, mica-schist, marble and graphite-schist. Serpentine, talc and clinochlore are only visible in the peripherals of deposit and occur as phases filling magnetite grains or as band and irregular mixtures with ore. It is reasonable to assume that any attempt to evaluate the formation of these mineral phases will help understand the genesis and evolution of Fe ore. Field studies, petrography and chemistry of serpentine, talc and clinochlore minerals indicate that these minerals were formed during three stages. In the high temperature stage (> 550°C), olivine formed. This was followed by the metasomatic stage, in which temperature and XCO2 dropped to < 250°C and >0.5, respectively.