盐池内流区地下水水化学特征及其形成作用

Hydrochemical characteristics and formation mechanism of groundwater in the inner flow area in Yanchi

对盐池内流区浅层地下水进行取样分析测试,采用描述性统计、Pearson相关性分析、piper三线图、Gibbs图、离子比例系数图等方法对该区浅层地下水的水化学特征及其成因进行了分析研究。结果表明:1)研究区浅层地下水总体呈偏碱性,硬度极大,属于微咸水,并且F-含量普遍偏高。2)研究区浅层地下水常量组分为Na^+、SO_4^(2-)、Cl^-,其次是HCO_3^-、Mg^(2+)和Ca^(2+),水化学类型以Cl-Na型和SO)4-Na型为主。3)地下水化学组分来源于硅铝酸盐矿物,碳酸盐矿物,以及岩盐、石膏等蒸发岩的风化溶解。4)地下水水化学特征的形成与溶滤作用、阳离子交换作用、蒸发浓缩作用、混合作用等有关,并以蒸发浓缩作用为主。

Analysis of shallow groundwater samples taken from the inner flow area in Yanchi was carried out firstly,and then the descriptive statistics,Pearson correlation matrices,the piper diagram,Gibbs diagram and the ratio coefficient of the main ions were used to analyze the chemical characteristics and causes of shallow groundwater in the area. Following results were obtained：（ 1） shallow groundwater of the research area in general is alkaline,brackish and of hardness greatly,and F-level is high widely in groundwater.（ 2） Major components of shallow groundwater are Na~＋,SO_4^（2-）,and Cl-,followed by HCO_3^-、Mg^（2＋） and Ca^（2＋）,and the major hydrochemical types are Cl^- Na and SO_4- Na.（ 3） Chemical composition of groundwater originates in aluminosilicate minerals,carbonate minerals,and evaporate minerals like rock salt and gypsum.（ 4） The formation of hydrochemical characteristics of groundwater is related mainly to mineral dissolution,cation exchange,evaporation concentrating,mixing,and evaporation concentrating is the key driver.