The Study on Mineralization of Jian Copper Deposit by Using Geochemical and Fluid inclusion Data, Fars Province

The Jian copper deposit is hosted by the Permo-Triassic SurianVolcano-Sedimentary Complex on the eastern edge of the Sanandaj-SirjanMetamorphic Zone at a distance of 195 Km NE of Shiraz, southwestern Iran. The complex consists mainly of metabasalt, chlorite-quartz schist, chlorite-muscovite schist, mica schist and graphite schist. Pyrite is the most important sulfide and chalcopyrite is the major Cu-bearing mineral occurred as massive ores in lens to nearly tabular shapes and also as disseminations in veins and veinlets hosted by chlorite-quartz schist. On the basis of geochemical data the mobile elements (Na, k, Ba, Sr) and rare earth elements (REE) show an intense influence of mineralizing fluid on the host rocks. Co/Ni=8.02, Y/Ho (29.09-32.5) and Se/S*106<500 ratio in Cu ores, indicate the important role of sea water in mineralizing system at temperatures below 300 ºC.The fluid inclusion microthermometric measurements on cogenetic quartz show homogenization temperatures from 124ºC to 307 ºC and salinities of 2/7–14 NaCl equiv. wt%. The petrographic and microthermometric investigations reveal that cooling and boiling of the mineralizing fluid are the most controlling factors oncopper mineralization in the Jian deposit. The deposit is classified as volcano- sedimentary hosted massive sulfide.