Characteristics of hydrochemistry and stable hydrogen,oxygen isotopes in surface water and groundwater in Jiyuan Basin

In the present study,hydrochemical components( K+,Na+,Ca2+,Mg2+,Cl-,SO2-4,HCO-3) and environmental isotopes( D,18O) were used as tracers to investigate the transformation relationship between surface water and groundwater in the Jiyuan Basin. We collected a total of 47water samples from rivers,shallow groundwater and deep groundwater for analysis. The results of hydrochemical study show that the main water type in the Jiyuan Basin is HCO3-SO4-Ca-Mg. Shallow groundwater and river water are closely connected. The hydrochemistry of different water bodies are mainly influenced by rock weathering. The results of deuterium and oxygen-18 analysis reveal that the precipitation is the main recharge source of various water bodies,and evaporation process took place after groundwater recharge from rainfall in the basin. Mild evaporation process occurred in the deep ground water,and intense evaporation process accured in the shallow groundwater and river water. The main recharge way for shallow groundwater and river water is through vertical meteoric precipitation infiltration,while the deep groundwater mainly accepts the recharge of water from Taihang mountains area at the altitude of 620—1185 m.