背斜构造区岩溶槽谷水文系统的离子特征与水-岩反应研究

Ion Characteristics and Water-rock Interaction of Karst Valley Hydrologic Systems in Typical Anticline Area

采取了19组典型的背斜构造区岩溶槽谷水文系统的水样基于水文地球化学基础理论,采用主成分分析、相关性分析和离子比例系数分析方法,对区域内的离子特征和水-岩反应进行研究。结果表明,水体中的阳离子相对丰度Ca^(2+)>Mg^(2+)>Na^+>K^+,其中Ca^(2+)为优势离子均值为101.64 mg·L^(-1);阴离子相对丰度HCO_3^->SO_4^(2-)>Cl^->NO_3^-,其中HCO_3^-为优势离子均值为237.62 mg·L^(-1)。提取特征根大于1的两个主成分(FACl和FAC2),与FACl密切相关的是Ca^(2+)、HCO_3^-、SO_4^(2-)、Cl^-、Mg^(2+)、Na^+,FACl贡献率达49.681%,反映的是水-岩作用,说明水-岩作用是区域水体离子的控制性因素,以方解石(CaCO_3)、白云石[CaMg(CO_3)_2]为主的碳酸盐矿物,石膏(CaSO_4·2H_2O)、硬石膏(CaSO_4)等硫酸盐矿物以及蒸发岩的水-岩作用是区域水体离子的主要来源。与FAC2密切相关的是NO_3^-、K^+、FAC2贡献率为21.320%,反映的是人类作用,说明人类活动对区域内水体离子具有一定影响。另外,K^+对FACl、FAC2载荷分别为0.430、0.776,说明K^+来源相对较为复杂,水-岩作用与人类作用对钾离子均有一定的贡献。

Take the 19 sets of typical anticline zone of Karst Valley hydrological system of water, based on the basis of hydrogeochemical theory, by the method of principal component analysis, correlation analysis and ion ratio coefficient, study on ion characteristics and water-rock reaction in the region. The results show that, The relative abundance of cationic water is Ca2＋〉Mg2＋〉Na＋〉K＋, Where Ca2＋ is the dominant ion, the mean for 101.64 mg？L-1, the relative abundance of anions is HCO3-〉 SO42-〉Cl-〉NO3-, Where HCO3- is the dominant ion, the mean for 237.62 mg？L-1. The extraction of two principal component eigenvalues greater than 1 （FAC1and FAC2）,FAC1 is closely related with the Ca2＋、HCO3-、SO42-、Cl-、Mg2＋、Na＋, the FAC1 contribution rate of 49.681%, the reflection of water rock interaction, water rock interaction is the controlling factor of regional water ions, calcite （CaCO3） and dolomite （CaMg （CO3）2） the main carbonate minerals, gypsum（CaSO4？2H2O）, anhydrite （CaSO4） and other evaporite sulfate minerals and water rock interaction is the main source of ion water. FAC2 is closely related with the NO3-、K＋, the FAC2 contribution rate of 21.320%, the reflection of human action, that human activity has a certain influence on regional water ions. Besides, K＋ on FAC1、FAC2 load is 0.430、0.776, explain K＋ source is relatively complex, the contribution of water rock interaction and human effect on potassium ion has certain.