Baskunchak

a salt lake in Astrakhan Oblast, RSFSR, 50 km east of the Volga River. The area of Baskunchak is 106 sq km. It is 19.5 m below sea level. The lake’s basin is a com-pensational syncline located south of the salt dome of Mount Bol’shoe Bogdo. According to other information, the lake may have originated on the site of a salt dome that was destroyed by the last transgression of the Caspian. The lake is fed by salt springs along the shore and on the bottom, as well as by atmospheric precipitation. As a result of evaporation in the summer, salts from the saturated solution—the saltwater—form a layer of salt (up to 5 or 6 cm thick) called novosadka and starosadka—schistose, small-crystaled salts (from 2–10 to 40 cm). Below these layers there are thick layers of salt called chugunki (from 0.5 to 2 m) and granatki (from 0.5 to 12 m). Granatki is a large-crystaled transparent salt—the best in terms of quality and commercial importance.

Until 1917 the deposits were extracted in a primitive manual way. (Up to 250,000 tons of salt were mined per year.) Since 1931 the industry has been mechanized. Deep mining of granatki salt (up to 7.2 m from the lake’s surface) is carried on by salt combines. Chugunki salt (up to 0.4 m from the lake’s surface) is mined by stonecutting machines. The yearly yield of salt from Baskunchak is about 4 million tons.