IANIGLA   20881
INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Permafrost and related forms in the Diamante Caldera (Central Andes, Argentina)
Autor/es:
D. TROMBOTTO LIAUDAT; VICTORIA ALONSO
Lugar:
Salekhard
Reunión:
Congreso; Tenth International Conference on Permafrost; 2012
Institución organizadora:
International Permafrost Association
Resumen:
The Diamante caldera is a volcanic depression located in the Central Andes, at 34º S on the Chilean-Argentine border, with two prominent reliefs: the Maipo Volcano (5323 m) to the west and the Laguna Diamante (around 7 x 3 km) to the east. The origin of this caldera is attributed to a large evacuation of ignimbrites, ~ 0.45 Ma ago. The construction of the Maipo volcano in this caldera took place much later, after a long period of no volcanic activity. The Diamante Caldera, widely glaciated during the Last Glaciation, still preserves some glaciers in favourable orientations, the most prominent covering the summit of the Maipo Volcano and mainly flowing to the south. Three small glaciers, with a south aspect, are located in the northwestern part of the caldera, while a glacier ice remnant lies in the northeast zone, with the front at 4550 m a.s.l. A geomorphological map was made for the analysis of the periglacial features in the area (rockglaciers, different forms of solifluction and patterned ground). In the same valley however, and considering the noses of cryoforms with creeping permafrost, cryogenic activity is observed at a height of 3750 m a.s.l. approximately. At other sites of the area cryoforms reach down to even 3600 m with signs of inactivity. It was produced on an ASTER image (15 m / pixel) using aerial photographs from 1963-64, at an approximate scale of 1:100 000, and the software of Adobe Illustrator.