The Beaujeu geological-fold accentuates the terrain belonging to Digne's geological-nappe (geological thrust-sheet).

The oldest geological-layers concerned, which appear on the other side of the Arigéol mountain-river, belong to the Lower Jurassic period (Lias Group) and were deposited about 185 million years ago.

This geological-fold is a westward-facing anticline (an upward convex fold) with an N-NW - S-SE axis, which places it in a family of geographical-deformations that may have occurred around 34 million years ago.

From here, the view is along the axis of the geological-fold.

At the time of the formation of this geological-fold, the terrain involved was located a few kilometres further north. It was only much later, around 10 million years ago, that Digne 's geological-nappe (geological thrust-sheet) moved to its present location.
 
Other similar geological-folds of the same period, and just as spectacular, can be seen in the neighbouring Bléone valley, towards Blégiers where they are superimposed on older geological-deformations.