| Summary: | Doctor en Ciencias, Mención Geología The Sierra Baguales Mountain Range (SBMR) forms the eastern foothills of the Patagonian Andes located between 50º and 51º S, topographically isolated from the Southern Patagonian Icefield (SPIF) and under the influence of the Westerly Winds. Its landscape shows glacial deposits and morphologies, potentially useful for the reconstruction of the Pleistocene Holocene glaciations, which occurred in the vicinity of the Patagonian Ice Cap, and possibly showed individual responses to environmental change after the Last Glacial Maximum (LGM). Using simple and multivariate statistical methods, the morphometry of 143 glacial cirques, distributed between the current eastern limit of the SPIF and the easternmost SBMR, approximately 200 km from the Pacific coast, was analyzed. For the latter sector, using photo-interpretation, Geographic Information Systems (GIS) and field work, the first glacial and periglacial geomorphological map of the area was constructed. The relationship between the Geological Strength Index (GSI), rainfall gradient, and cirque areas, which were occupied and eroded by former alpine glaciers, was also established. To this end, theoretical profiles of the ice topography, based on a perfect plasticity model, were developed. Ages of local environmental changes were estimated using 14C dating. Equilibrium Line Altitude (ELA) variations were interpreted based on geomorphological evidence and the accumulation area ratio (AAR).The lowering of the ELA was converted to the change in temperature by multiplying it with an average atmospheric lapse rate. For the SBMR, it is possible to recognize two glaciation levels which rise towards the interior of continent. Their spatial distribution and elevation were controlled by tectonic factors (Andean uplift), the rainfall gradient and the climate contrast from east (temperate maritime) to west (dry cold), present in southern Patagonia since the LGM. The lower group of glacial cirques is distributed in the lower areas of the main ...
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