(6)            The landslide of le bois de la Glaivaz (Ollon)

Fig. 1  : Views of the main scarp of the landslide and the recent debris slide.

West to the village of Ollon part of the wood of la Glaivaz is affected by a landslide similar to a gravitational sagging. It is located in Triassic gypsum and anhydrite of the sub-médiane zone of the Swiss Prealps. This landslide begun probably after the last glacier retreat, like many landslides in the Swiss Alps (Fig. 1). 

Within the ancient main scarp a recent debris slide can be observed (Fig. 2). This debris slide is a good example of multi-risk interaction (forest fire – landslide), it initiated after a forest fire that occurs on the 20 March, 1997 (Fire info: La Presse).

Fig. 2 : Views of detail of the recent debris slide.

References:

Wichser F. (1997) : Incendie du Bois de la Glaivaz à Ollon. La presse.