贵州威宁草海地区地下水化学特征与控制因素研究

运用数理统计、Piper图、Surfer软件对研究区地下水化学特征分析。结果表明:地下水化学组分以Ca~(2+)、HCO_3~-为主,其次为Mg~(2+)和SO_4~(2-),TDS均值为519.34 mg·L~(-1),各离子含量由孟家山断层与威水背斜中间地带向两侧逐渐递减。运用Gibbs图、离子比例系数、相关性分析对研究区地下水化学的控制因素研究。结果表明:地下水化学离子组成受蒸发-浓缩作用和大气降水作用影响小,岩石的风化溶滤作用是水化学离子的控制性因素。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)等硫酸盐矿物以及盐岩的风化溶滤是区域地下水离子的主要来源,其中以方解石(CaCO_3)、白云石[CaMg(CO_3)_2]等碳酸盐矿物的风化溶滤作用最强。

Hydrochemistry characteristic and The control factor of Groundwater of Caohai Area in Weining County, Guizhou Province

In this paper, the statistics, Piper diagram and Surfer software were used to analyze the groundwater chemical characteristics in the study area. The results showed that: Major ions in groundwater is dominated by Ca₂₊ and HCO_3-, followed by Mg₂₊ and SO_42-. The mean value for the TDS is 519.34 mg?L_-1. Ions content from middle to both sides gradually decreasing in Mengjiashan fault and Weishui anticline. Using Gibbs diagram, ion proportionality coefficient and Correlation analysis on the control factors of groundwater chemical research. The results showed that: Rock weathering, leaching are the controlling factors hydrochemistry ions. Evaporation, concentrated and atmospheric precipitation small influence on it. Main ion source of groundwater is rich in CaCO₃, CaMg(CO₃)₂ carbonate minerals, gypsum(CaSO₄?2H₂O),sulfate minerals and Halite. Water sources of main ions is carbonate minerals rich in CaCO₃, CaMg(CO₃)₂, gypsum, sulfate minerals and Halite weathered and leached. Among them, the carbonate mineral weathered and leached strongest.