| Summary: | This research analyses,from a point of view both quantitative and qualitative, the situation of thePyramid Glacier, located in the Andean basin of the Maipo River, at 33° 35' S and 69° 53' W, withan average altitude of 3565 m. With a length of 6.5 km, an average thickness of 54,64 m and anicy section of 0,026 km2, is estimated a volume of dirty ice equivalent in 135,2 million liters ofwater. Morphologically corresponds to the type of covered glacier, whose debris mantle presentsvarying thickness between 30 cm and 1 m, which related to an average of 4.2° gradient determinesnone advance movement. This is corroborated by the absence of ridges and furrows that are properlyof the active rock glaciers. On the other hand, its surface presents a chaotic topography product ofdifferential ablation according to thickness of the morainic mantle. It presents thermokarst phenomena,like moulins, kettles and depressions of collapse with walls of ice 20 to 30 meters high, where there aremultiple debris-icy layers. These walls presents continuous landslides of detritic material, as well asstreams of melt water that circulate in the contact zone (active layer). At the bottom of depressions occurlagoons of different dimensions as well as tunnels occupied by seasonal water flows. The dimensionsof these forms of ablation and collapse have registered variations in its dimensions, as well as haveappear new depressions and accentuate the topographic irregularities, which reveals a strong negative mass balance with increase of the processes of melting, thinning and instability of the ice mass, whichis associated with the decrease in the in-puts because dominance of the La Niña phenomenon since2009 and the rising temperatures trends as shows the 0° C isotherm altitudinal changes. Se analiza la situación del Glaciar Pirámide, ubicado en la cuenca andina del Río Maipo, a los 33°35' S y 69° 53' W, y a una altitud media de 3565 msnm, desde un punto de vista tanto cuantitativocomo cualitativo. Con una longitud de 6,5 km, un espesor medio de ...
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