Hydrochemistry Characteristics and Its Control Factors in Sedimentary Metamorphic Iron Deposit under Conditions of Mining: A Case Study of Southern Sijiaying Iron Mine Area

In order to understand the hydrochemistry characterization variation tendency of the aquifer after the sedimentary metamorphic iron deposit mined, on the basis of the division of aquifer system and development law of the flow system in the mining area, through the analysis of relevance of conventional ions, hydrochemistry types and common factors on 148 groundwater samples collected from the Upper Quaternary aquifer, the Lower Quaternary aquifer and the bedrock aquifer, the hydrochemical type distribution and the isolines of common factors scores were obtained, then they were overlaid to analyze potential formation and controlling factors of the aquifers. The results show that Upper Quaternary aquifer is characterized by the carbonate dissolution, pollution and oxidation; the Lower Quaternary aquifer is characterized by the pollution, the carbonate dissolution and the local sulfate reduction; the bedrock aquifer is characterized by ion exchange adsorption, the mixing effect of the Quaternary aquifer and incongruent dissolution of silicate. In addition to background factors, three-dimensional flow field has controlled the formation and original hydrochemical types of the bedrock aquifers, and has affected the local formation of the Quaternary aquifer to make hydrochemical type boundary move significantly.