Permafrostkartierung im Gebiet der Hochebenkar-Blockgletscher, Obergurgl, Ötztaler Alpen
The occurrence of permafrost in the region of the Hochebenkar rock glaciers has been mapped in detail. For this purpose basal temperatures of the winter snow cover were measured at over 250 sites (BTS-method), 11 refraction-seismic profiles were taken in frozen and unfrozen unconsolidated sediments and 12 springs were investigated in terms of their summer temperature variations. The combination of seismic refraction and the BTS-method allows rapid and reliable mapping of alpine permafrost, and at the same time enables differences in active-layer thickness to be established. The results of the observations confirm the ideas developed in the Swiss Alps in recent years about the relationships between permafrost and rock glaciers: rock glaciers are creep phenomena of discontinuous alpine permafrost.