The Velodrome Recumbent Fold - France

The Velodrome Recumbent Fold - France

The Velodrome is a large recumbent fold spilled southward, formed at the end of the Tertiary (23 to 5 million years) at the Alpine front.

The Vélodrome fold is made up of a series of sedimentary layers, initially deposited at the bottom of this marine gulf. A first set of deposits was deposited, very sandy at the base then clay-sandy, these are the marine molasses. With the intensification of the deformations, erosion is very active and the sediments, transported by rivers and streams, are more and more abundant until gradually filling the sea. This is how the marly and conglomeratic deposits ( with pebbles) of the yellow continental molasse succeed (around -12 million years ago) to the marine molasse. When it settles around -12 to -3 million years ago, the layers of sea molasse are already partly straightened.

Molasses accumulated at the foot of the reliefs in the Alpine sedimentary basin Valensole, along which the fold of the Velodrome was formed. The term evokes the Velodrome, used by geologists from the 50s, means the marine basin filled and distorted.