[Hydrochemical Characteristics, Controlling Factors and Water Quality Evaluation of Shallow Groundwater in Tan-Lu Fault Zone （Anhui Section）].

To study the hydrochemical characteristics, controlling factors, and groundwater quality of the Tan-Lu fault zone (Anhui section), 86 groundwater samples were taken from the areas surrounding the Tan-Lu fault zone (Anhui section), which included the Jianghuai Wavy Plain, the Yanjiang Hill Plain, and the Dabie Mountains in western Anhui. Descriptive statistics, Piper diagram, Gibbs diagram, ion ratio analysis, saturation index, chloride-alkalinity index, and entropy weight water quality index (EWQI) were used to comprehensively study the hydrochemical characteristics and controlling factors of groundwater and to evaluate its quality. The results showed that the shallow groundwater in the Tan-Lu fault zone (Anhui section) was weakly alkaline, with dominant anions and cations of HCO