Morphological indications of hypogene speleogenesis in caves of the Urals (Russia)

Approximately all types of surface and underground karst elements are represented in the Urals. Rock formations are elongated in the longitudinal direction, which allows for a comparative analysis of the processes in karst landscapes in different latitudinal geographic areas. During the long geological history of the Urals, karst development occurred in conditions of extensive occurrence of soluble rocks in the territory and in the geological section in cratons, folded zones and depressions. The most intense karstification occurs in Paleozoic sediments. Sulfate rocks (gypsum and anhydrite) located on the eastern margins of the East European Craton and adjacent parts of the Ural Foredeep are the most karstified. These deposits are also intercalated with thin layers of limestone and dolomite of the Irenskaya Suite, and to a lesser extent—limestones and dolomites of the Filippovsky Unit of the Kungurian Stage and limestones of the Artinskian Stage of Lower Permian. Salt-bearing and sulfate deposits are mainly found in the Ural Foredeep. Karst development in the Devonian, Carboniferous, and Permian carbonate strata with a total thickness of more than 2000 m is typical for the folded zone of the West Ural and Central Ural uplifts. The western slope of the South Urals is the most intensely karstified. Hypogenic karst cavities occur from the Polar to the Southern Urals on the western and eastern slopes. The article presents the most interesting examples of hypogenic speleogenesis in the Ural.