GLACIERS AND ROCK GLACIERS DISTRIBUTION AT 28º SL, DRY ANDES OF ARGENTINA, AND

PERUCCA, L. ESPER ANGILLIERI M Y

Environmental Earth Sciences

Springer

Lugar: Berlin; Año: 2011 vol. 64 p. 2079 - 2089

1866-6280

 The studied area includes a little-known portion on the dry Andes of the San Juan Frontal Cordillera, Argentina, which has not been previously studied in terms of glaciers and rock glaciers hydrological significance. The surveyed sector includes Cerro El Potro (5,870m ASL) and nearby mountain chains (28ºS). The predominant landforms in these areas have been shaped in a periglacial environment superimposed on an earlier glacial landscape. Featured by abundant rock glaciers, these regions comprise a noteworthy rock glacier zone of the World which, nevertheless, is little known in South America. This work employs geomorphological mapping to analyze the distribution of active rock glaciers in relation to altitude, aspect and slope using optical remote sensing techniques with GIS. Statistical estimation techniques were used based on a DEM (Digital Elevation Model) and air photo and Spot images interpretation. The specific density of rock glaciers estimation in the surveyed area (Argentine border) is 1.56% with corresponds to 38 rock glaciers with an area of 5.86km2 and 0.12km3 of water equivalent.  Furthermore, the analytical results show that elevations >4270 m ASL, a southeastern-facing aspect, and slope between 2º and 40º favor the existence of rock glaciers, Finally, a comparison with glacier water equivalent, which covers an area of ~16 km2 and 0.9 km3 of water equivalent, shows that glaciers are the main stores of water at 28º S (Cerro El Potro Glacier). However, the importance of rock glaciers as water reserves in this portion of Argentina, should not be underestimated