On the hydrogeology of karstosphere: the case of the Urals and the Urals region

This article considers the hydrogeological parameters of the karstosphere and emphasises its unstable regime in the transit areas. Deep karst water zones and their catchment areas are more stable, in discharge areas they are characterised as weakly thermal. The sulphate karst is the site of formation of sulphate-calcium water with mineralisation of ≥ 3.5 g/l. Sulphate-sodium and soda subtype water with mineralisation of 0.3÷0.5 g/l forms in the areas of development of younger sediments. The hydrochemical method proved to be very efficient when studying karst.