PERMAFROST DISTRIBUTION AND ROCK GLACIERS IN THE LIVIGNO AREA (NORTHERN ITALY)

Geophysical investigations were undertaken in the Livigno area (Sondri o, northern Italy) during 1991-92 at a number of sites where permafros t had been suggested through the application of other techniques, such as geomorphological studies, measurements of bottom temperature of wi nter snow cover (BTS), measurement of ground temperature in summertime (STG), and temperature of spring waters. Geoelectrical surveys confir m and characterize these permafrost occurrences. Furthermore, they ind icate that, outside the rock glaciers, permafrost is also present in s ome gelifluction lobes. The permafrost bodies differ with regard to pa rameters such as resistivity, depth and thickness. Resistivity ranges from 18,000 to 560,000 Ohm m (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.