Miocene Magmatism Magma Sources in the Southern Andes

HALLER MJ; OSTERA HA; CAGNONI M

Kiel

Simposio; 20th Colloquium on Latin American Earth Sciences; 2007

Kiel University

New data on crustal components suggest an increasing of Upper Crustal components in the Tertiary Magmatism of the Southern Andes from Early to Late Miocene times. The isotope modeling suggests that the lower crustal component varies from Early to Middle Miocene, due the continuous influx from the mantle to the MASH zone. The explanation for the major upper crust involvement towards the Late Miocene could be the slab flattening, which provokes a compressional regime and evolution of magmas in depth. The role of crustal erosion is still not well defined in the area, although some geochemical evidences are compatible with it.