Karst

South of France’s Massif Central lie the limestone plateaus that form the Grands Causses region. Bordered by the deep valleys of the Tarn and Jonte rivers, the Causse Méjean is the highest of these plateaus. Its distinctive landscape, known as karst, is marked by the mechanical and chemical erosion of limestone rock. Water seeping through cracks in the surface of the plateau has created a unique topography, characterised by surface phenomena and an extensive network of underground cavities. These cavities, known locally as avens (or sinkholes), are chasms that open up in the ground. Varying in depth and appearance, they are mostly difficult to access, as they take the form of a vertical shaft over all or part of their length. Explored since Neolithic times for the resources they contain (water, calcite, clay), and once considered the entrance to Hell in a land where Catholicism predominated, these abysses and their exploration were brought to light in the 19th century by a young lawyer with a passion for geography. At the end of the century, when photography was invented, Edouard-Alfred Martel and his collaborators carried out numerous explorations in the Causses Majeurs region, thus contributing to its development as a tourist destination and to the foundation of modern speleology.

In photography, development refers to the process of transforming a latent image into a visible image. In caving, development corresponds to the cumulative length of the interconnected galleries in an underground network. What can we see underground? What shapes can we recognise, and what stories do those that are still unknown to us tell? Through the exploration of a dozen natural cavities in the Occitanie region using a large-format film camera, and thanks to the insights and tools of geomorphologists, geologists, hydrogeologists and geoarchaeologists, Développements invites us to think of underground environments as infinite laboratories of visions, which continue to reveal the archives of the history of the Earth and its inhabitants. Work conducted in collaboration with scientists from the GET (Geosciences Environment Toulouse) and TRACES (Archaeological Research on Cultures, Spaces and Societies) laboratories, the SETE (Theoretical and Experimental Ecology Station) - CNRS in Moulis and the BRGM (Bureau of Geological and Mining Research) Occitanie.