Hydrochemical and isotopic characteristics of groundwater in Panhe area of Wumeng Mountain, Yunnan

This paper aimed at studying hydrochemical chemical characteristics in Wumeng Mountain1 50000 Wuzhai sheet.On the basis of hydrogeological survey in the study area, groundwater samples were collected, and the cluster analysis and factor analysis were used to discuss the relationship between the result and groundwater quality assessment.The results show that the main chemical type of groundwater in the study area is HCO₃-Ca type, and the hydrochemical components have obvious spatial variability. The main factors controlling thehydrochemical composition of groundwater in the study area are water rock interaction time, aquifer medium type and human activities.The isotopic test results confirm that the circulation of shallow groundwater is fast and the evaporation is less, and the salt source of groundwater is mainly dissolution and leaching of minerals.The groundwater quality in Panhe area is good, especially the type A water in the water rich structure of shallow weathering fissures of basalt is the best, which is suitable for the development and utilization.Type B water is mostly typical solution filtered water in sedimentary rock area.Type C water is class V water, and the over standard index is mainly SO₄^2-, which comes from the dissolution of primary minerals and the water inflow of abandoned coal mines.Most of the D-type water passes through the middle and deep circulation.The cluster analysis method can identify the formation and evolution process of groundwater, which has guiding significance for water supply well site selection, discovery of mineral water resources and water quality evaluation in the study area.