Permafrost distribution and rock glaciers in the livigno area (Northern Italy)

Abstract Geophysical investigations were undertaken in the Livigno area (Sondrio, northern Italy) during 1991–92 at a number of sites where permafrost had been suggested through the application of other techniques, such as geomorphological studies, measurements of bottom temperature of winter snow cover (BTS), measurement of ground temperature in summertime (STG), and temperature of spring waters. Geoelectrical surveys confirm and characterize these permafrost occurrences. Furthermore, they indicate that, outside the rock glaciers, permafrost is also present in some gelifluction lobes. The permafrost bodies differ with regard to parameters such as resistivity, depth and thickness. Resistivity ranges from 18,000 to 560,000 ωm (ohm metres), depth varies between 8 and 21.1 m, and the active layer is 2 to 4.7 m thick in those bodies that can be considered active on the basis of morphological features.