The panoramic landscape of the Col d’Hysope mountain-pass unfolds to the south and allows you to see the entire Duyes valley, of which the eastern edge shows, in the foreground, the overlapping of the Digne geological-nappe (or geological thrust-sheet).

The Digne geological-nappe (or geological thrust-sheet) is made up of terrain ranging in age from 265 to 180 million years old, resting on much younger layers, in particular the Valensole conglomerates (mixed composites of various rocks) which are only 8 to 2 million years old.

This abnormal situation of recent layers being covered by older ones is called a geological thrust-sheet. The geological thrusting, or advancement, was facilitated here by the presence of gypsum at the base of the Digne geological-nappe (or geological thrust-sheet).