Fig. 2

Geological overview of the Voirons Nappe. a Tectonic map of the Voirons Nappe and its relation with the surrounding units, with the location of boreholes and of the geological sections depicted in Fig. 3. Inset: close-up on the Saint-Gingolph area. b Geological map of the Voirons Flysch based on the Annemasse sheet (Kerrien et al. 1998) and the Douvaine sheet (Olive et al. 1987) of the French Geological map. Inset: close-up on the Dranse outcrop. MA: La Maladière; CCA: Colline des Châteaux des Allinges