Geothermometry and physiochemical condition ofQaleh- Zari Cu-Au ore bearing solution based on chloritecomposition and fluid inclusion study

Qaleh-Zari mine is the largest Cu-Au vein type deposit in Iran and is located about 182 km south of Birjand (Khorasan province). The ore grade ranges from Cu= 0.5-8%, Au= 0.5-15 ppm, and Ag= 20-150 ppm. Mineralization concentrated in three major veins. Host rock. .. are mainly andesite to basaltic andesite (paleocene-Eocene). The main paragenesis is: quartz. hematite (specularite), chlorite, chalcopyrite, ± pyrite, ± Ag-sulfosaJts, and ± gold. Samples were collected from three veins at depth of -70, -100, -135, and -1 70 meters. At each level, sample. .. are taken every 10m. Chlorite. .. arc mainly Fe-rich ripidolite, however a few sam pels are brunsvigite and pycnochlorite. Temperature or chloritcs formation were calculated based on the Cathelineau and Nieva (1985) equation. The chlorites were formed between 260-300"C. The temperature of chlorite fonnation is to-3erC less than temperature measured from fluid inclusion. Using chlorite composition and fluid inclusion data from Qaleh- Zari, new equation ichr('39')l presented for calculation of temperature for chlorite formation . The ore tluid contained log mH,S= -3 to -3.5 , log mH, < -5.5 , log f02= -30 to -29.