Hydrogeological peculiarities of the karst processes development in the Urals

The hydrogeological peculiarities of fissure-karst waters of the Urals and Pre-Urals are characterized. The springs of transitional zone have the instable regime. The springs feeding from the more deep fissure-karst zones are more stable, have slightly thermal character and considerable discharges. The active karst of sulphate type is connected genetically with the formation of waters with the sulphate-calcium composition and mineralization up to 3,5 g/l. On the places where sulphate rocks are overlapped by the recent sediments, the decreasing of karst processes are accompanied by the formation of waters with the reducted mineralization (0,3-0,5 g/l). The sulphate-natrium subtype of water here sometimes changes to the soda type. The hydrochemical method of karst study is elaborated.