Пещера Вашанская близ Казначеево (Тульская область) (original) (raw)

The abandoned underground limestone quarries, situated in the vicinity of Kaznacheyevo village, in the River Vashana basin (the Oka right tributary), have been found and surveyed by our research group since 2017. These quar- ries operated in the late 19th – early 20th centuries. While surveying their underground cavities, two accessible natural caves formed with landslide fault were discovered. The largest one was named the Vashana cave. Its total length is more than 140 meters and its height reaches 13 meters. The cave genesis is associated with deep-seated landslides of the Late Pleistocene. Such large caves, located in plains, are poorly described in scientific literature. The detailed characterization of geological conditions and the local relief along with the cave description, its interior photos and its preliminary map are presented in this paper. According to incision/aggradation rhythms a primary joint system and a karst horizon split by the cave were formed at least since the end of MIS 6 and throughout the Late Pleistocene. We have previously established the main stages of the cave’s evolution based on these data and field materials. Previously we established that the main volume of the Vashana cave resulted from the removal of geostatic pressure and the occurrence of a landslide during the last episode of rapid bedrock channel incision 18–12 thousands of years ago.