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This study aimed to determine the hydrochemical characteristics and hydrogeochemical processes of shallow groundwater in the Jinta Basin, northwest China, and to evaluate the suitability of groundwater quality for drinking water and agricultural irrigation. A systematic hydrogeological survey was conducted in the study area from May 2017 to October 2018, during which 123 representative samples of groundwater were selected for analysis of chemical parameters and determination of the water quality index. The results showed that the pH of groundwater in the study area was weakly alkaline and ranged between 7.21–8.93. Dominant cations were Mg2+ and Na+ and the dominant anion was SO42−. Along the groundwater flow from the southwest to northeast, the dominant groundwater chemistry type in the recharge area was Mg-HCO3·SO4. After the transition of the groundwater types in the runoff area to Mg-SO4·HCO3 and Mg·Na-SO4, the groundwater type in the discharge area evolved into Na·Mg-SO4·Cl. The major factors driving the evolution of groundwater chemical types in the Jinta Basin were found to be rock weathering, evaporation and precipitation. The chemical components of groundwater mainly originated from the dissolution of silicate rock and evaporative concentration of salt under water-rock interaction, whereas the dissolution of carbonate had little influence. The quality of drinking water was divided into five groups, and 39.84% of samples fell within the high and good quality groups. The quality of agricultural irrigation water was divided into different grades according to different methods.

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Karst water resources is about 24% of the total amount of groundwater resources that can be exploited in China. Among the 15 groundwater sources in Tailai Basin, there are 12 karst water sources, accounting for 80%. With the survey and evaluation data of groundwater sources in Shandong Province, hydrochemical types analysis of karst water is carried out by Schukalev classification and The trilinear chart by Piper, and it is of great significance to development and utilization of karst water. The hydrochemical types of karst water is dominated by HCO3·SO4-Ca water. However, if the naming of hydrochemical types involve nitrate, excess 39% of the karst water hydrochemical types changes. In addition, historical data shows that the concentration of nitrate in karst water has gradually increased, so it is recommended to increase nitrate indicators in the classification of hydrochemical types.