Inventorying glaciers and periglacial landforms in the Volcán Domuyo area (36º S), Northern Patagonian Andes of Argentina, using ALOS satellite data

DANIEL FALASCHI

San Miguel de Tucuman

Taller; XXVI Reunión Científica de la Asociación Argentina de Geofísicos y Geodestas & Taller Internacional: La Geomática en las Ciencias de la Tierra; 2012

The Volcán Domuyo is an eroded startovolcano that exhibits an alpine-type glaciation, and is located in the northernmost tip of the Patagonian Andes. Major goal of this study was to compile a glacier and periglacial landforms inventory and to evaluate the potential of different ALOS datasets for this task. A supervised classification of a false color composite, 10m resolution ALOS AVNIR2 image and additional manual corrections yielded a total of ca. 25 km2 of glacier area. Active and inactive rockglaciers and protalus, which were manually digitized based on  2.5m resolution ALOS PRISM images, cover ca. 12.5 km2. A 10m resolution digital surface model was generated in order to extract morphometric parameters of glaciers and periglacial landforms (minimum, mean and maximum altitude, mean aspect, mean slope, hypsometry). The results indicate that the proposed supervised classification of ALOS AVNIR2 images provides reliable results, as strong as other glacier mapping semi-automatic techniques such as LANDSAT or ASTER band ratios thresholds. Furthermore, ALOS PRISM images have a high resolution that allows for consistently identifying small periglacial landforms, not perfectly visible in coarser resolution images. From the characteristics of the criospheric components in this site, it stems that the Volcán Domuyo area features resemble more to the Central Andes rather than the Patagonian Andes.