МЕТАН И СЕРОВОДОРОД В ДОННЫХ ОТЛОЖЕНИЯХ ВОДОХРАНИЛИЩ И ПРУДОВ БАССЕЙНА АЗОВСКОГО МОРЯ

Abstract

Gas-geochemical studies of bottom sediments and water of Sokolovsky, Grushevsky, Artemovsky, Veselovsky, Proletarsky, Tsimlyansky reservoirs and other dammed reservoirs were carried out. Concentrations of CH4 and ΣH2S in sediments vary from 0.02 to 61.3 μg/g and from <0.01 to 8.36 mg/g of wet sediment, respectively. The highest concentrations of CH4 are observed in the deposits of the Artemovsky, Tsimlyansky and Veselovsky reservoirs, and ΣH2S – in the deposits of the Proletarian, Tsimlyansky and Grushevsky reservoirs. The distribution of CH4 and ΣH2S along the vertical profile of sediments is characterized, as a rule, by an increase in concentrations from the surface layer to the subsurface horizons, in which their maximum peak is recorded, after which the concentrations decrease. The difference between the distribution of ΣH2S and the distribution of CH4 is the more frequent fixation of maximum concentrations of ΣH2S in less deep layers of sediments. The percentage of CH4 from the sum of the studied reduced gases (the coefficient of methanization of КCH4) in sediments varies from 0.004 to 11.1 %, which indicates a significant dominance of the process of sulfate reduction over the process of methanogenesis. The closeness of the relationships of the concentrations of CH4 and ΣH2S between themselves and the values of КCH4, pH and Eh deposits is analyzed.