HUANG Wangwang1,2, JIANG Chunlu1,2, CHEN Xing1,2, FU Xianjie3, CHEN Shigui3, ZHENG Liugen1,2
(1. School of Resource and Environmental Engineering, Anhui University, Hefei 230601, China
2.Anhui Province Engineering Laboratory for Mine Ecological Remediation, Anhui University, Hefei 230601, China；
3. China Coal New Energy Co., Ltd., Huainan Anhui 232000,China)
Abstract: In order to find out the ion composition and the evolution characteristics of deep groundwater in the Xinji mining area, 20 water samples from the study area, such as sandstone water and limestone water in the Taiyuan formation, were collected, conventional ion and hydrogen and oxygen isotope analyses were conducted, Piper three-line diagram and correlation analyses were implied and ion ratio and saturation index methods were used to study chemical composition characteristics of these water and to investigate hydrogeochemical effects of ions on these waters. The results showed that: (1) the sandstone water is a high salinity water, mostly are the Cl-Na type water, the limestone water in the Taiyuan formation is a medium mineralization water, whose water chemical type is either the HCO3·Cl-Na type or the Cl-Na-type; (2) the groundwater recharges in the study area included not only atmospheric precipitation and surface water, but also paleo-filtration-infiltration water formed under paleoclimate conditions, which caused the oxygen isotope drift due to the interaction of minerals and deep groundwater; (3) The main water-rock interactions in these groundwaters are the dissolutions of silicates and evaporating salt rocks and the alternating adsorptions of cations. The groundwater of the mining area is over-saturated in terms of dolomite and calcite.
Key words: Sandstone water; limestone water in taiyuan formation; water chemistry; ion scale coefficient; saturation index
EARTH AND ENVIRONMENT Vol.48, No.4, Tot No.336, 2020, Page 432-442
