Volcanological and geochemical evolution of the Diamante Caldera-Maipo Volcanic Complex in the Southern Andes of Argentina (34° 10´S).

PATRICIA SRUOGA; MAUREEN FEINEMAN

Nisyros, Grecia

Workshop; International Summer School of Volcanology; 2009

Asociación de Volcanología de Italia

The Diamante Caldera - Maipo Volcano Complex (DCMVC) is a historically active stratovolcano nestled within a collapse caldera, located at 34° 10´ south latitude in the Andean Cordillera, on the border between Argentina and Chile. It belongs to the northern section of the Southern Volcanic Zone (SVZ), which extends continuously from 33° to 46°S. The SVZ is commonly divided in three segments, a northern section (NSVZ: 33°-34.5° S), characterized by thicker continental crust and more silicic magmas, which contain significantly more radiogenic Sr and more strongly fractionated REE, in comparison to the transitional (TSVZ: 34.5º-37º) and the southern (SSVZ: 37°-46°) sections (Hildreth and Moorbath, 1988). Maipo volcano, 5323 m high, was emplaced at the western portion of the Diamante caldera. At present, the two summit craters remain ice-covered. The lack of fumarolic or hydrothermal activity and an uncertain historic record (1826?, 1829?, 1905? and 1912) turns this volcano suspiciously quiet, compared to neighboring volcanic centers.