Iron Oxide-Copper-Gold-Type Mineralization in Machanur Area, Eastern Dharwar Craton, India

Parallel to the Krishna river course, a set of ENE to WSW trending brittle-ductile shear zones affecting the Neoarchaean pink porphyritic granite remains athwart to the NW-SE tectonic fabric of the Eastern Dharwar Craton (EDC) in Raichur and Gulbarga districts, Karnataka, India. These zones are not only manifested by intense mylonitization, brecciation and fracturing, but also witness several episodes of mafic and felsic intrusions. At Machanur, Raichur district a 5 km long and 400 m wide shear zone hosts copper, gold and REE mineralization both in specularite-rich hydrothermal veins and as disseminations within the dolerite dykes. The mineralization is associated with well-developed zones of hydrothermal alteration in the form of propylitization, carbonatization, epidotization and silicification with patches of strong iron-staining and fracture-filled iron solution dominantly in the foot wall side. Due to similarity with many iron oxide- copper-gold-type deposits, this prospect in Machanur is interpreted as iron oxide-copper-gold-type mineralization.