Karst remnants of the Southern Urals and Cis-Urals

Based on the literature data and results of field research, the locations of karst remnants, the type and age of karsting rocks they formed in, as well as the morphology and morphometry of the remnants were determined. In the Southern Cis-Urals, the remnants were formed in gypsum of the Kungurian stage on the Pribelskaya plain and in the western foothills of the Southern Urals, as well as in limestones of the Sakmarian and Artinskian stages on the Ufa plateau. In the Southern Urals, they were formed in limestones and dolomites of the Upper Devonian and Early Riphean within the low-mountain ridges of the western slope. In the Southern Cis-Urals, karst remnants are represented by hills, ridges and outcrops of bedrock rising above the flattened surrounding terrain, and in the Southern Urals, they are isolated low mountains and pillars. The sizes of the remnants are small – a few tens of meters. In the Southern Urals, their sizes are larger than in the flat Cis-Urals, which is due to the higher hypsometric position of their locations and the formation of remnants in carbonate rocks that are more resistant to the effects of denudation agents than in sulfate rocks. Based on the analysis of the geological and geomorphological conditions of the locations of karst remnants and the leading exogenous geological process that determines their formation, all the characterized remnants are divided into three main types: erosion-karst, the formation of which is mainly due to the activity of river erosion, karst-denudation, associated with the phenomenon of unloading rock pressure in river valleys and kastogenic, formed in the bottoms of karst basins of collapse genesis. The most numerous remnants are erosion-karst, and the least common are kastogenic. The formation of karst remnants in the region presumably began in the Early Pleistocene, the formation of which continues at the present time.