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The evolution of magmatic arcs in porphyry copper systems formation: Southern Peru Fernando Nuñez and Adolfo Manrique, Southern Peru Copper Corporation, Lima, Peru The Andes range, the most important tectonic feature of South America, is the product of tectonic-orogenic deformation processes, which are associated with the generation of magmas in different geological epochs. These, in turn, are directly or indirectly related to the formation of metal-bearing ore deposits, remarkable porphyry systems, among other. The geodynamics of tectonic-orogenic episodes are characterized by distension and compression phases, which are associated with the formation of magmatic arcs such as the so-called volcanic island arcs of the Jurassic-Lower Cretaceous, those of the Cretaceous-Paleocene and those of the Lower Oligocene; all of them related to the generation of mineralization systems of economic value in Peru and South America. The evolution of magmatic arcs are related to the formation of economically exploitable porphyry systems of Cu-Au, Cu-Mo, or Cu-Mo-Au. Research results show that the magmatic arcs that evolved from the Jurassic-Lower Cretaceous to the CretaceousTertiary are also genetically related to economically minable copper-gold mineralization in porphyry systems that were emplaced in the so-called coastal range, as was the case of La Tapada and Tia Maria. These porphyry systems indicate that in the western edge of the South American plate a volcanic island arc existed, with the presence of tholeitic magmatism that evolved into calc-alkaline magmatism which, contrary to what was previously assumed, are related to the occurrence of economically minable copper mineralization with absence of molybdenum and presence of gold. The Cretaceous-Paleocene magmatic arcs are related to typical porphyry systems known as Andean porphyries such as Cerro Verde, Toquepala, Quellaveco, Cuajone, among others, which are associated to intermediate calc-alkaline magmatism with copper and molybdenum mineralization, which develop marked hypogene alteration halos that have been widely known and researched; however, according to recent work these systems show the presence of economic mineralization at depths exceeding 1,200 meters of mineralized column with alteration assemblages of higher temperature, as is the case of Toquepala. Regarding the Oligocene magmatic arc emplaced on the eastern part of the Western Range, a number of porphyry systems have been recognized, mainly Las Bambas and Los Chancas, which systems are related to calk-alkaline magmas rich in potassium feldspar associated with economically minable mineralization of copper, molybdenum and gold. The petrographic characteristics of the plutons associated with this type of mineralization show deep emplacements, embedded in thick sedimentary strata with developments in areas of alteration-mineralization, different from known systems with individual assemblages; these peculiar features of the system may correspond to a new sub-type among Andean porphyry systems.