鲁西南黄河下游地下水氟富集规律及其影响因素OA北大核心CSTPCD

The southwestern plain of Shandong Province is located in the lower reaches of the Yellow River,and there are few studies on the chemical genesis of groundwater in this region and the mechanism of its influence on fluorine enrichment in groundwater at this stage.In this study,36 shallow groundwater samples,16 deep groundwater samples and 2 Yellow River water samples were collected for comprehensive analysis and testing.By means of statistical,correlation analysis and water chemistry simulation,the chlor-alkali index(CAI),Durov diagram,Gibbs diagram,Ca2+/Na+-Mg2+/Na+diagram,log10(Ca2+)activity-log10(F-)activity diagram were constructed,and then the causes of groundwater chemistry and its fluoride enrichment mechanism in the study area were analyzed.The results showed that the chemical types of both shallow and deep groundwater in the study area were mainly HCO3-Na,indicating the overall alkaline,the fluorine content of groundwater was 1.59 mg/L and 2.35 mg/L,respectively,and the level of fluorine content in deep water varied less than that in shallow water.The fluorine content in shallow groundwater in the area was significantly negatively correlated with Ca2+content and positively correlated with pH value.The fluorine content in deep groundwater was significantly and positively correlated with Na+and TDS values.The chemical composition of groundwater in the study area is mainly controlled by water-rock action and cation exchange,and the fluorine content of groundwater mainly comes from the dissolution of fluorite(CaF2),and is controlled by Ca2+content.This study revealed the fluorine enrichment laws and influencing factors in the main groundwater aquifers in the lower reaches of the Yellow River.