Major hydrogeochemical processes controlling arsenic enrichment in groundwater of the Datong basin, Northern China
As concentration and speciation were studied of 146 groundwater samples of the Datong basin,northern China. It was shown that Astot,As(Ⅲ) andAs(Ⅴ) are in the range of0.4-1932, 0.2-1060 and 0.2-872 μg/lrespectively and the ratio of As(Ⅲ)/As(Ⅴ) is 0.36-4.1, with an average of 1.4. High arsenic groundwaters from the Datong basin are mostly soda waters, with TDS between 0.4 and 10.5g/l and pH between 7.6 and 9.1.Geochemical modeling indicates that the waters are oversaturated with respect to calcite and clay minerals such as kaolinite, and are always undersaturated with respect to primary rock forming minerals such as anorthite and albite. The water chemistry is also affected by continental salinization. Results of our hydrogeochemical studies indicate that the occurrence of soda water is one natural stage of water-aluminosilicates interaction, which happens when the water is saturated with respect to calcite, and under the condition that salt accumulation of evaporative enrichment is not strong or even absent. The soda-forming process creates a favorable geochemical environment for As enrichment in groundwater at Datong.
Y.Wang S.L.Shvartsev
Key Laboratory of Biogeology and Environmental Geology of Ministry of Education,China University of Tomsk Department of Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the R
国际会议
第十二届水-岩相互作用国际研讨会(P0roceedings of the 12th International Symposium on Water-Rock Interaction)
昆明
英文
1123-1126
2007-07-31（万方平台首次上网日期，不代表论文的发表时间）