Tectonic settings, genetic types and main metallogenic features of copper-gold deposits in Papua New Guinea

The complex geological framework of Papua New Guinea comprises such structural elements as platform, collisional orogen, allochthonous terrane, subduction zones, island arcs, and seafloor spreading centers. Papua New Guinea’s copper-gold deposit types include porphyry copper-gold deposits, epithermal gold and silver deposits and skarn copper-gold deposits，which have a close time-space genetic relationship, as well as submarine massive sulfide deposits. Copper and gold deposits in Papua New Guinea are mostly concentrated in collisional orogenic belts and island arcs as well as modern seafloor spreading centers. Most of the copper and gold deposits in Papua New Guinea are giant or large in size, and are characterized by shallow burial depth, easy exploration and suitableness for open-pit mining. Copper and gold deposits in Papua New Guinea are associated mostly with calc-alkaline volcanic rocks and intrusive rocks, and subordinately with potassium-rich alkaline volcanic rocks (shoshonite) or intrusive rocks. Alteration and mineralization zones are generally well developed in the copper and gold deposits of Papua New Guinea. Copper and gold deposits in Papua New Guinea are mostly related to the porphyry system and/or volcanic edifice. Although mineral compositions of many copper and gold deposits in Papua New Guinea are complex, the ores of these deposits can be quite easily processed and utilized.