The Bay of Ecalgrain

The cliffs of Écalgrain Bay show traces of ancient landslides, revealing the alternation of glacial and temperate periods over nearly 200,000 years.

As for the foreshore, the alternation of different rocks (sandstone and shale) is evidence of sea level variations between 540 and 430 million years ago. The sandstone formed in a shallow and turbulent marine environment, unlike the shale, which indicates the deposition of sand in a deeper and calmer environment.

The symmetry of these layers between the northern and southern parts of the bay indicates the presence of a fold of tectonic origin (the Jobourg syncline). The most recent layers are located in the center. This fold is linked to the formation of the Hercynian mountain range.