Late stage condensation-corrosion in high mountain marble cave (Val di Scerscen, Bernina Massif, Valtellina, Italy)

International audienceVal di Scerscen is located in the Central Italian Alps (Northern Lombardy), in the scenic setting of Valmalenco. This area is not very rich in caves, especially due to the abundant presence of oceanic metamorphic rocks, which where uplifted during the Alpine orogenesis, dominate the terrains. A thin lens of whitish dolomitic marbles belonging to the Austroalpine Margna Nappe (on the geological sketch represented by pink, light blue, and yellow colors) hosts a few short caves, right at the end of the tongue of the Scerscen glacier, on the southern slopes of Bernina Piz. This glacier and its meltwater probably strongly contributed to the cave evolution. The most important caves, opening at about 2600 m asl, are: Veronica cave (length: 638 m), Morgana cave (348 m), and Tana dei Marsooi (77 m). These are typical epiphreatic caves with juvenile pattern and with adjustment to the water table (Audra and Palmer, 2013), according to the glacier evolution and to the valley incision. With the important retreat of the glacier during the Holocene, the processes of cave evolution have changed. The runoff provided by the glacier became less and less important and the drainage changed with the migration of the tongue of the ice cover. Today, the groundwater flow is mainly active during spring due to snow melting on a restricted catchment. The underground climate is characteristic of alpine caves, with a low mean temperature. Actually the condensation corrosion processes are dominant int the cave evolution. With 3 D model (Laserscanning and photogrammetry), and genomic analysis this study try to understand the dynamic of the recent evolution of these caves