Gorges du Tarn

The Gorges du Tarn is a canyon formed by the Tarn River between the Causse Méjean and the Causse de Sauveterre, in southern France. The canyon, mainly located in the Lozère département, and partially in the Aveyron département, is about 53km-long and 400 m to 600 m deep.Geography and geologyThe architecture of the gorges involves Mesozoic limestone plateaux downstream presenting sub-vertical cliffs. Faults like the Hauterive Fault explain the important water sources in the region of Sainte-Enimie (the Burle source and the Coussac source, the latter joining the Tarn in an impressive waterfall), and the more complex geology in the upstream part of the canyon.In the Quaternary, the gorges were also affected by a volcanic activity whose traces can be found in the Causse de Sauveterre, in the form of a double or anticlinal volcanic dip, and in the basaltic rocks next to Eglazines.