Space-Time Relations between Mineralization and Magmatism: Argentinian Andes (27"-28")

Abstract

New regional geological compilation and field work, including petrological and geochronological data, facilitated the reconstruction of the volcanic history of the southern end of Central Volcanic Zone in Argentina (between 27O-28OS). Cenozoic arc migration and broadening extended volcanism over several geological provinces such as Cordillera Frontal, Precordillera, Famatina and Pampean Ranges. Four major volcanic events built different volcanic arcs in this Andean segment: 1) a Paleogene magmatic arc, 2) an Oligocene-Early Miocene volcanic arc (the Maricunga Belt), 3) a Late Miocene volcanic arc which migrated and broadened to the east, and 4) a Pliocene-Quaternary volcanic arc that is today represented by fumarolic activity on Nevado's Ojos del Salado volcano. The volcanism developed above a thickened crust and was accompanied by the emplacement of important copper-bearing porphyries and development of epithermal precious metal deposits.