GRAN SOMETTA (Cervinia - I)

Active rock glacier

Elevation: 2640-2800m  -   Massif: Penninic Alps (Grand Tournalin)  -   Commune: Valtournenche (I)  

The Gran Sometta rock glacier is a complex landform with several lobes. The rooting zone of the rock glacier was covered by a local glacier during the Litte Ice Age and is today almost free of permafrost. The lower part of the rock glacier is active, in particular its orographic left side. Within the framework of a partnership between ARPA and University of Fribourg, the first systematic measurements have started in 2012.


  • Measurements and observations

    Thermal (ground surface temperature, temperature in boreholes)
    Geodetic (GNSS, deformation in boreholes)
    Remote Sensing (aerial images using drone)
    Geophysics (electrical resistivity)

  • Figures

    Annual horizontal surface velocity of the rock glacier. Mean of selected sets of points in several sections.



    Ground surface temperature at three measurement sites on the rock glacier.



    Mean annual ground surface temperature at three measurement sites on the rock glacier.



    Contribution of the annual Ground Freezing (sum of all daily mean values < 0°C) and Ground Thawing (>0°C) Indexes to the mean annual ground surface temperature (MAGST) on a set of selected locations (n) on the site. Or : how cold was the winter and how warm was the summer at the surface of the ground ?



    Annual dates of the start and end of the snowmelt period (zero curtain phase). Mean of n sensors placed on permafrost terrain. The dotted lines show the mean dates since the beginning of the time series.



  • Collaboration

    ARPA Val d’Aoste (U. Morra di Cella, P. Pogliotti)

    Further measurements (temperature, geophyisics, soil moisture) are undertaken at the North Pass of Cime Bianche by the ARPA and the University of Fribourg (project SOMOMOUNT, Prof. C. Hauck, C. Pellet)

  • Publications

    Dall’Asta, E., Delaloye, R., Diotri, F., Forlani, G., Fornari, M., Morra di Cella, U., Pogliotti, P., Roncella, R., and Santise, M. (2015). Use of UAs in a high mountain landscape: the case of Gran Sommetta rock glacier (AO), Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XL-3/W3, 391-397. DOI: 10.5194/isprsarchives-XL-3-W3-391-2015