Characteristics of formation of chemical composition of groundwater of active water exchange zone of the Bodrak catchment area (South-Western Crimea)

Abstract

The article focuses on study of the chemical composition of the groundwater zone of active water exchange. The site of research was the Bodrak catchment area (South-Western Crimea). Formation of groundwater is caused by the infiltration of precipitation. Its chemical composition is influenced by natural and anthropogenic factors, but primarily it is determined by the enclosing sediments. At the same time, a leading role belongs to the sand-and-clay and volcanic-sedimentary rocks of Triassic and Jurassic. The predominant ions in the chemical composition of groundwater are mostly HCO3–, Ca2+. Factors affecting variations of chemical composition of groundwater of active water exchange in the Bodrak catchment area are revealed. First of all, this is the chemical composition of the enclosing sediments, under the influence of which the differences in the composition of the groundwater of sandy-argillaceous, volcanogenic-sedimentary horizons (T2—J1) and carbonate deposits (Cretaceous Paleogene) are formed. The nitrate ion and the association of Zn—Fe—Cu—Pb—Ni—Al in the groundwater zone of active water exchange are associated with anthropogenic impact. The series of elements Sb—As—Se—Co—Mo—Sn—Ag can be connected with the numerous sulfide nodules characteristic of rocks of flysch deposits (T2—J1) and carbonate deposits (Cretaceous—Paleogene).