This site is a reference for geologists as it bears witness to the transition of the Valanginian age (139 million to 134 million years ago) to the Hauterivian age (134 million to 131 million years ago). It is in the candidate section of the official list of Global Boundary Stratotype Sections and Points (GSSP). Why do you say that Serre de l’Ane is a point of reference?
This site is a reference for geologists as it bears witness to the transition of the Valanginian age (139 million to 134 million years ago) to the Hauterivian age (134 million to 131 million years ago).
The site of Serre de l’Ane is in the candidate section of the official list of Global Boundary Stratotype Sections and Points (GSSP), which defines the lower boundaries of stratigraphic stages (here, the Hauterivian). These international references form a sort of “rung” in the ladder of the geologic timescale.
These stratotypes are selected by the international scientific community and are given the status of a “golden spike”: only one is given per geological stage.
It is, therefore, of inestimable value as a site of geological heritage, which we must protect and nurture.