Title screen

Conditions of manifestation, feature of chemical and isotope composition of soda groundwater of the southern part of Kuzbass - the world's largest coal basin have been studied. It is shown that soda groundwater is widely developed here within of coal-bearing sand-clay of Paleozoic sediments, are confined in zone of slow water exchange at depths from 100-200 up to 2000 m. At the same time soda groundwater are presented quite variously on chemical and isotope compositions, that has allowed to allocate them in three groups: 1) soda groundwater with a low mineralization (0.2-5 g/l) of the upper part of zone of slow water exchange (at depths of about 100-1000 m) with values δD from -125.6 ‰ to -101.8 ‰, δ18O: from -17.7 ‰ to -15.0 ‰ and δ13C from -12.4 ‰ to -6.7; 2) soda groundwater with a high mineralization (up to 25 g/l) of the lower part of zone of slow water exchange (at depths of about 400-2000 m), which enriched 18O (δ18O from -14.9 ‰ to -11.9 ‰) and 13C (δ13С from +4.7 to +30.9‰); 3) soda groundwater with СО2 of mixed genesis (δ13С from -12.3 to -3.9 ‰) (in certain points). It was determined, that three groups have infiltration origin and first both groups have biogenic source of carbonic acid.