Caracterización isotópica del sistema periglacial hídrico de la cuenca del río Vallecitos, Mendoza, Argentina. Nuevos aportes

TROMBOTTO LIAUDAT DARÍO; SILEO NOELIA; DAPEÑA, CRISTINA

San Miguel de Tucumán

Congreso; XX Congreso Geológico Argentino; 2017

Asociación Geológica Argentina

The Vallecitos river basin is in the northwest of Mendoza province, between 69º19´ and 69º26´ W and 32º 55´ and32º 59´ S, in Cordón del Plata, Cordillera Frontal. This basin comprises three sub-basins, formed by old glacier valleys, which now are filled by diverse cryogenic forms. The objective of this work is the isotopic characterization of groundwater and surficial waters related to glaciers, rock glaciers and covered glaciers. Different mechanisms of precipitation in the recharge area and on cryoforms as well as surficial courses were observed. Rainfall was registered up to slightly above 3600 m above sea level. Stable isotopes of H and O have been used as natural tracers and to understand the ground water circulation. The depleted isotopic composition is not only the result of altitude effect but also caused by the degradation of perennial snow patches of the periglacial environment that suffered evaporation and sublimation during several years. A contribution of melting water from a rock glacier of the lower basin cannot be ruled.