Relationship between thermokarst and surges of the Horcones Inferior Glacier, Aconcagua, Mendoza, Argentina

LENZANO, MARÍA GABRIELA; TROMBOTTO, DARÍO

GEOGRAFISKA ANNALER SERIES A-PHYSICAL GEOGRAPHY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2010

0435-3676

ABSTRACT This work analyses the temporal evolution of thermokarst and their relationship to the surges in a reconstituted debris covered glacier. The glacier Horcones Inferior is located at 32º 41’ S and 69º 57’ W in the Provincial Park Aconcagua, Mendoza, Argentina, on the foot of the Aconcagua massif. The study and monitoring of the thermokarst was carried out applying indirect methods using Landsat images of the years between 1985 and 2006. Inferences to understand the processes and the internal dynamics of the glacier and the evolution of the surges were made. Detected percentages of thermokarst, in relation to the total glacial area, showed that they varied between 4.5% to 0% at the end of the surge. The registered speeds of the glacier -on the glacial surface- reached averages of between 2 and 11 m/d. The temporal follow up of the thermokarst can help to prevent a surge phenomenon or to alert about its immediate possible occurrence. This methodology, with historical images from archives, represents a fundamental tool to reconstruct historical glacial and cryogenic catastrophic and non-catastrophic events.