Volumetric ice content in active rock glaciers derived from geophysical modeling (Central Andes of Argentina)

CARLA TAPIA BALDIS; JAN HENRICK BLÖTHE; CHRISTIAN HAUCK; CHRISTIAN HALLA

Chamonix-Mont-Blanc

Conferencia; 5th European Conference on Permafrost; 2018

Laboratoire EDYTEM, CNRS, Université Savoie Mont-Blanc

Active rock glaciers potentially constitutesignificant water reservoirs and sources in the dry Central Andes. However,volumetric ice and water contents of Andean rock glaciers are largely unknown. Inthis study, the so-called four-phase model (4PM) is applied in order toquantify the material composition of the talus-derived rock glacier Dos Lenguasand the large rock glacier complex Morenas Coloradas. The 4PM is based on different porosity models forice-rich permafrost bodies and ongeoelectric andrefraction seismic tomography that were conducted in the root zone, middle partand on the tongues of both rock glaciers. The spatialdistributions of ice and water contents show a heterogeneous pattern. Ice-oversaturatedpermafrost and massive ground ice with ice contents of 50 up to 90 vol%are two to three times higher in root zones of both rock glaciers compared tolower lying rock glacier tongues containing 20 to 30 vol%.