巴中市恩阳镇地区浅层地下水水文地球化学特征分析

Hydrochemistry Characteristic of Shallow Groundwater in Enyang County,Bazhong City

通过采取研究区45组浅层地下水样,基于水文地球化学基础理论,运用数理统计、Piper三线图、Gibbs图、相关性分析、离子比例系数分析和水化学平衡分析,对研究区地下水水文地球化学特征进行研究。结果表明:地下水化学组分中,阳离子以Ca^(2+)为主,均值为91.11 mg·L^(-1);阴离子以HCO3-为主,均值为330.15 mg·L^(-1);TDS均值为481.2 mg·L^(-1);地下水化学类型主要为HCO_3-Ca型。研究区地下水系统属于开系统,主导研究区地下水水化学特征的是岩石风化溶滤作用,碳酸盐矿物的风化溶滤是研究区地下水离子的主要来源,以方解石(CaCO_3)、白云石[CaMg(CO_3)_2]溶滤为主,其中,方解石大部分处于非饱和状态(SI_C小于1),白云石处于饱和状态(SI_D大于1)。

Sample analysis,hydrochemistry theories,the statistics,Piper diagram,Gibbs diagram,correlation analysis,ion proportionality coefficient and hydrochemistry equilibrium were used to analyze the shallow groundwater hydrochemistry characteristic in the study area.The study showed： major ions in groundwater is dominated by Ca^2＋ and HCO3^-.The mean value for the TDS is 519.34 mg·L^-1.The hydrochemistry types is mainly HCO3-Ca type.Rock weathering,leaching are the controlling factors hydrochemistry ions.Main ions sources of groundwater is mainly carbonate minerals rich in CaCO3 and CaMg（CO3）2weathered and leached.Among them,Ca CO3 is not saturated（SIC 〈1）,Ca Mg（CO3）2is oversaturated（SIC〉 1）.