Temporal evolution of magma sources in Miocene magmatism, Southern Mendoza, Argentina

OSTERA, H., HALLER, M., MACAMBIRA, M., RAMOS, A., CAGNONI, M., LÓPEZ DE LUCHI, M.G., LINARES, E

Punta del Este, Uruguay

Simposio; Fifth South American Symposium on Isotope Geology (SSAGI); 2006

Universidad de la República

New results on geochemical and isotope data, modeling and evolution of Tertiary magmatic units from Lower to Upper Miocene in Southern Mendoza are presented. They suggest an increasing of Upper Crustal components in the Tertiary Magmatism from Lower to Upper Miocene times. The isotope modeling indicates that the Lower Crustal component varies from Early to Middle Miocene, due to the continuous influx from the mantle. The explanation for the major Upper Crust involvement towards the Upper Miocene could be the slab flattening, which provokes a compressional regime and the emplacement of most evolved magmas. The role of crustal erosion is still not well defined in the area, although some geochemical evidences are compatible with it.