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.

The contribution of geoelectrical investigations in the analysis of periglacial and glacial landforms in ice free areas of the northern foothills (northern victoria land, antarctica)

“…3). The resistivity curve obtained is very similar to the curves typically obtained for Alpine rock glaciers (Haeberli 1985;Guglielmin et al 1994). The active layer was not detectable because it is very thin (5 cm).…”

“…On the basis of previous experience in alpine areas (Guglielmin et al 1994) we chose to use the vertical electric soundings (VES) method to identify the different types of ground ice.…”

The climatic significance of rock glaciers

“…Some maritime rock glaciers may even initiate and remain active in regions with a MAAT slightly above 0 8C, as was suggested by Birnie and Thom (1982), based on ®eld evidence from South Georgia, southern Atlantic. Also, the descriptions given by Eyles (1978), Guglielmin et al (1994), Whalley et al (1995b), and Kirkbride and Brazier (1995) suggest that active rock glaciers may occur within regions with a comparatively high regional precipitation (1000±1700 mm).…”

The origins of Antarctic rock glaciers: periglacial or glacial features?

“…In Antarctica, to the best of our knowledge when submitting this paper, only the Tumbledown Crags rock glacier on James Ross Island has been drilled (at two boreholes) (Fukui et al, 2008). The internal structures of some rock glaciers were investigated through geophysical electrical soundings (especially vertical DC soundings in the past and, more recently, by means of electrical resistivity tomography (ERT) (Haeberli, 1985;King et al, 1987;Evin and Fabre, 1990;Guglielmin et al, 1994Guglielmin et al, , 1997Hauck, 2001;Hauck et al, 2001;Maurer and Hauck, 2007;Ribolini et al, 2007Ribolini et al, , 2010 and ground penetrating radar (GPR) (Berthling et al, 2000;Lehmann and Green, 2000;Degenhardt et al, 2003;Fukui et al, 2007;Hausmann et al, 2007;Monnier et al, 2008;Degenhardt Jr., 2009;Leopold et al, 2011;Merz et al, 2015;Hartl et al, 2016). The internal structures of some rock glaciers were investigated through geophysical electrical soundings (especially vertical DC soundings in the past and, more recently, by means of electrical resistivity tomography (ERT) (Haeberli, 1985;King et al, 1987;Evin and Fabre, 1990;Guglielmin et al, 1994Guglielmin et al, , 1997Hauck, 2001;Hauck et al, 2001;Maurer and Hauck, 2007;Ribolini et al, 2007Ribolini et al, , 2010 and ground penetrating radar (GPR) (Berthling et al, 2000;Lehmann and Green, 2000;…”

“…Even less known are the natural exposures of rock glacier internal structures, as reported, for example, by Strelin and Sone (1998) and Ribolini et al (2007). The internal structures of some rock glaciers were investigated through geophysical electrical soundings (especially vertical DC soundings in the past and, more recently, by means of electrical resistivity tomography (ERT) (Haeberli, 1985;King et al, 1987;Evin and Fabre, 1990;Guglielmin et al, 1994Guglielmin et al, , 1997Hauck, 2001;Hauck et al, 2001;Maurer and Hauck, 2007;Ribolini et al, 2007Ribolini et al, , 2010 and ground penetrating radar (GPR) (Berthling et al, 2000;Lehmann and Green, 2000;Degenhardt et al, 2003;Fukui et al, 2007;Hausmann et al, 2007;Monnier et al, 2008;Degenhardt Jr., 2009;Leopold et al, 2011;Merz et al, 2015;Hartl et al, 2016). A comprehensive review of several geophysical techniques applied to detect massive sub-surficial ice was reported by Yoshikawa et al (2006).…”