贺兰山西麓典型干旱区绿洲地下水水化学特征与演变规律  

Hydrochemical Characteristics and Evolution Laws of Groundwater in Typical Oasis of Arid Areas on the West of Helan Mountain

作　　者：姜凌[1] 李佩成[1] 郭建青[1] 

机构地区：[1]长安大学环境科学与工程学院,陕西西安710054

出　　处：《地球科学与环境学报》2009年第3期285-290,共6页Journal of Earth Sciences and Environment

基　　金：国家科技攻关计划项目(2002BA901A43)

摘　　要：针对地下水资源过量开采而出现的绿洲水文生态问题,以贺兰山西麓具有典型特征的内蒙古腰坝绿洲为研究对象,分开采期、非开采期对地下水进行系统取样分析,综合运用描述性统计、相关性分析、离子比例系数和Piper三线图示法,全面系统地研究了地下水水化学的时空变异特征与演变规律。研究结果表明:①季节变化对潜水和承压水水化学类型空间变异性影响较小,潜水水文化学性质受外界因素干扰较大,承压水受外界因素干扰较少;②蒸发浓缩、阳离子交换和人为混合是控制研究区潜水水质演变的主要水文化学过程;③潜水子系统总溶解固体较高,水化学类型变化也较复杂,主要从HCO3.SO4.Cl-Na.Mg.Ca型向Cl.SO4.HCO3-Mg.Na、Cl.SO4-Na.Mg型演化。承压水水化学类型比较单一,主要以低矿化度的HCO3-Na.Mg.Ca型为主。The paper takes the Yaoba oasis of Alxa area on the west of Helan mountain as the typical study case,and the groundwater samples are analyzed systemically,then the descriptive statistics,the correlation matrices,the ratio coefficient of the main ions and the piper diagram are used to gain the better understanding of the spatial and the temporal variation of the hydrochemistry characteristics and the evolution laws of groundwater.The results show that： ①Hydrochemical spatial variability of unconfined and confined aquifer is almost not affected byseasonal variation, and the interference of external factors to hydrochemical character of unconfined aquifer is more obviously than confined aquifer; ②The following main hydroehemical processes are inferred to control the water quality of the groundwater system： the evaporative condensation, ion-exchange reactions, and mixing of the surface water with high salinity; ③There are high TDS contents and complicated hydrochemical types in unconfined aquifer, whose hydrochemical types evolve from HCO3 ·SO4 · CI-Na · Mg · Ca to Cl · SO4 · HCO3-Mg · Na, CI · SO· Na · Mg. The hydrochemical types of confined aquifer are simple, which mainly are HCO3 Na · Mg · Ca with low-mineralization.

关 键 词：干旱区绿洲 地下水 水化学类型 时空变异 演变规律 

分 类 号：P641.3[天文地球—地质矿产勘探]