A high-altitude cave as an example of active karstification in the eastern Tibetan Plateau

Karstification and cave development on the eastern Tibetan Plateau are generally significantly decelerated or interrupted because of low temperatures and relatively dry conditions. Speleothems deposited in the late Pleistocene and the last thousand years imply active karstification in Tibet during warm and wet interglacials. However, few caves have been surveyed on the eastern Tibetan Plateau, hindering the assessment of the processes influencing, and the degree of, cave and karst development in the region. Here, we present a truncated cave from the eastern Tibetan Plateau that initially developed under phreatic, and was further enlarged under vadose conditions. Xiaosumang Cave is a sub-horizontally multi-level maze cave with active speleothem deposition. Cave air temperature is 7±0.3°C, relative humidity is 96±1.9% and cave air CO, has been recorded at 622±46 ppm. Due to infiltration and microclimatic conditions and availability of modern speleothems the cave has been selected as a key site for palaeoclimatic studies. Karst springs and caves in the vicinity indicate extensive speleological potential. Spatially extensive speleological exploration and surveying would provide an important database for regional variations in the temporal development of Tibetan karst. U-series dated speleothems from multiple caves will provide detailed information on the Quaternary glaciological, hydrological and thermal history of the World's highest plateau.