The Arvel quarry is located at the end of the Rhône valley (southwestern Switzerland) and is one of the most important producers of ballast and other construction material in Switzerland. On the 12 December 2008, a rockslide of about 20'000m3 occurred in the upper part of the quarry. In the same area, a potential unstable rock mass with a similar mechanism has been identified. By means of terrestrial laser scanner (TLS) and field analysis, we assessed the present-day stability of the quarry and we analyzed the mechanisms and the triggering factors of the 2008 rockslide. This analysis showed that the stability of the entire quarry is strongly controlled by pre-existing discontinuity sets and the triggering factors for rock instabilities in the area are related to freeze and thaw cycles and changing in water pressure on fractures.
The Arvel quarry is located in southwestern Switzerland close toVilleneuve (Fig. 1a).The rock forming the slope aboveVilleneuve has been extensively exploited as construction material since the middle ages. The site of the actual quarry is industrially exploited since 1905. The quarry has experienced several rockslides and rockfall events during the last century. The most important event occurred on March 13th 1922, when a rockslide of about 600'000m3 destroyed partially the extraction machinery. Recently, on December 12th 2008, a rockslide of about 20'000m3 occurred on the upper part of the quarry. Because of this event and unstable rock spur detected in the same area, an important portion the quarry extraction is presently stopped. This article illustrates the application of remote sensing techniques and field analysis in order to analyze and model the potential trigger mechanism of the 2008 rockslide and to assess the present-day stability of the upper part of the quarry.
