About Chablais - Geological Overview

The Chablais lies in the Prealps thrust belt situated at the edge of the western Alps.

Erratic block Erratic block It has experienced a huge variety of geological settings: continent, rift, ocean, subduction zone and orogeny. Each of these phases can be explored through the territory’s geosites. The Chablais provides a condensed window into the history of the Alps through its rare, almost complete, succession of Alpine nappes. This unique geology underpins the distinct geography, cultural heritage and economic development of the territory.

  • Dent d’Oche Dent d’Oche The Chablais was once situated at the heart of the Pangea supercontinent; it was flooded by shallow seas on its breakup in the late Triassic. Strong evaporation gave rise to thick gypsum depositions.
  • Jurassic dolomites, limestones, marls and shales were deposited in Alpine Tethys which was over 1000km wide.
  • Compression progressively stacked these deposits and transported them by thrusting into the Chablais.
  • Collision between Europe and Africa-Apulia thickened the continental crust leading to further uplift and deformation.
  • Sculpting of the landscape by the great glaciations – eroded and deposited sediments to form our landscape.
  • Today the area displays examples of every type of mountain aquifer – including those of international renown such as that giving rise to Evian Natural Mineral Water.