Mineralogy, alteration, geochemistry, and fluid inclusion studies of the Balazard Cu-Au prospect, southwest of Nehbandan
The Balazard prospecting area is located about 120 km southwest of Nehbandan city, Khorasan Jonoobi Province, in the central parts of Lut block volcano-plutonic belt. The intrusion of a granitoid pluton into rhyolitic and andesitic rocks has led to alteration and mineralization. Hydrothermal alteration zones consist of argillic, sericite-argillic, silicic-argillic, propylitic, and advanced argillic. Sulfide and oxide mineralization occur as disseminated grains, veinlet, hydrothermal breccia and carbonate-silicic veins. The geochemical and radioisotope data are consistent with subduction related magmas that formed in an active continental margin, and these data suggesting a major interaction with upper crust during magma ascent. Microthermometric measurements of fluid inclusions yielded homogenization temperatures (Th) of 385–550 °C and moderate salinities of 7.1–21 wt% NaCl equivalent in Au bearing quartz vein, indicating the mixing of ore-forming fluids. Geology, mineralogy, alteration, fluid inclusions and geochemical studies all indicate that mineralization at Balazard area occur as both porphyry and high sulfidation epithermal systems.