The chosen definition for geodiversity has been taken from Sharples (SHARPLES, 1995): it represents the whole of subsoil, soil and landscape elements that, when assembled altogether, make up some organized systems that are provided from geological processes. This concerns the past phenomenon of planet Earth (signs of life, of ecosystems and of the environment), that are observable in subsoils, soils and landscapes that current phenomenon (biological, climatic, atmospheric) that act on the same subsoils, soils and landscapes (EBERHARD, 1997).
Photo: a view on the Grandes Jorasses and the Dent du Géant from the top of the Aiguille du Midi. © A.Cornée.
Man's understanding of nature has, until now, limited itself to living elements (fauna and flora), to natural habitats and environments. The geological elements, minerals - non-living elements - were not or less considered. However the link between geosystems and ecosystems is a fact: the present ecosystems are just the last image of a film that the geologist will try to restore. The Earth's geological environment and history provide some clues that allow to understand the evolution of life and of the present biodiversity.
Unlike the biological species, the geological objects do not reproduce themselves and the deterioration of an object, of a site leads it to its permanent lost: the conservation and preservation are not to be considered as insignificant. The preservation, like the highlighting of certain sites appears to be particularly relevant, when it allows an added value to the understanding or to the conservation of the natural surrounding diversity.
The notion of geodiversity has slowly imposed itself in certain international programs for the safeguard of the heritage as a stand-alone entity. Today, a number of initiatives are taking turns on the international, European or even the French scene in order to concretely recognize the concept.