Cryogenic landforms in the Sierras de Alvear, Fuegian Andes, subantarctic Argentina

Abstract

A preliminary survey of periglacial landforms found in the Monte Alvear region of the Fuegian Andes, subantarctic Argentina has revealed the presence of nivation hollows, subnival 'boulder' (clast) pavements, protalus ramparts, debris lobes, patterned ground and cryo-ejected clasts. With the exception of debris lobes and cryo-ejected clasts, all the landforms show some degree of activity and are, therefore, considered as indicators of present-day cryonival morphodynamics at higher elevations in these mountains. A number of small tors, while not necessarily periglacial in origin, are also apparently experiencing cryogenic weathering.