Rockfall in Alpine climatic area: remarks from multi-instrumental monitoring on a landslide in Salzburg Land

This work provides some remarks on results from multi-instrumental monitoring for the Ingelsberg landslide (Bad Hofgastein – Austria), that is one of the most dangerous landslide of Salzburg Land. The unstable area is located very close to the village of Bad Hofgastein within the Gastein Valley. It is a rockfall that cover an area of about 4 hectares, which is characterized by the outcropping of anti-dip stratified green and calc-mica schists. The monitoring campaign was implemented from March 2013 to December 2013 using several monitoring instrument such as terrestrial interferometry, meteorological data, extensometers and cameras. The present work shows some results about the reliability of entire monitoring system, through a statistical comparison of surface displacement recorded by GBInSAR and displacement in depth given by extensometers, during one of the most large rockfall events registered during the campaign. Moreover the main landslide events are discussed by analyzing both historical temperature time series (HISTALP) and those from local weather stations, recorded during the last century.