Geologicheskii Vestnik

The work is devoted to new caves, explored in 2022–2024 in the Ashkul ravine of Aurgazy region of the Bashkortostan Republic. Investigated territory belongs to the Aurgazy karst-speleological area of the Ryazan’ — Okhlebinino rampart of the eastern edge of the East — European Platform. The area is characterized by the sulfate rocks outcropping which are attributed to the Kungurian Stage of the Lower Permian and are intensively eroded by karst process. Dry valley, fields of sinkholes, caves of considerable length were developed in the Ashkul ravine. The caves form a uniform hydrogeological system. It has been established that the cave passages of the lower level are predominantly developed in nodular anhydrites, while the volumetric cavities of the upper levels are formed in medium-grained gypsum. Many caves in the Ashkul ravine have seasonal and perennial ice deposits confined to nearslope fractured zones. The karst and speleological potential of the Ashkul ravine is favourable for organizing excursion routes and further investigations.

karst country of the East European Plain, Metropolitan Cave, Ashkul ravine, speleology, sulfate karst, Bashkortostan Republic

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