神府矿区不同含水层水力联系的水化学证据  

Hydrochemical Evidence for Hydraulic Connection of Different Aquifers in Shenfu Mining Area

作　　者：吴亚坤 谢臣臣 孙魁 范靓慧 孙亚乔[1,2] 马雄德[1,2] WU Yakun;XIE Chenchen;SUN Kui;FAN Jinghui;SUN Yaqiao;MA Xiongde(School of Water and Environment,Chang’an University,Xi’an 710054,Shaanxi,China;Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region,Ministry of Education,Xi’an 710054,Shaanxi,China;Key Laboratory of Mine Geological Hazard Mechanism and Control,Xi’an 710054,Shaanxi,China)

机构地区：[1]长安大学水利与环境学院,陕西西安710054 [2]旱区地下水文与生态效应教育部重点实验室,陕西西安710054 [3]矿山地质灾害成灾机理与防控重点实验室,陕西西安710054

出　　处：《西北地质》2023年第6期198-208,共11页Northwestern Geology

基　　金：陕西省重点研发项目“渭河陕西段综合治理的水环境效应及应对关键技术(2020ZDLSF06-04)”;“黄河流域(陕西段)土壤-地下水污染管控与修复关键技术研究(2021ZDLSF05-05)”联合资助。

摘　　要：神府矿区是陕北能源化工基地重要组成部分,煤矿开采过程中矿水害防治是亟待破解的科学问题与生产实践问题。其间,厘定不同含水层水力联系,可直接为水害防治提供科学依据,基于此,笔者综合利用水化学、多元统计学和^(2)H、^(18)O、^(3)H同位素方法分析神府矿区萨拉乌苏组、直罗组风化基岩和直罗组基岩含水层间的水力联系。结果表明,研究区各含水层pH值均为7~11,为碱性水。萨拉乌苏组与直罗组风化基岩地下水TDS均值分别为294.55 mg/L和267.72 mg/L,属于低矿化度淡水;直罗组基岩地下水TDS均值为867.35 mg/L,矿化度较高。萨拉乌苏组与直罗组风化基岩含水层主要水化学类型为HCO_(3)-C a型水,直罗组基岩含水层主要水化学类型为HCO_(3)-Na型水和HCO_(3)·SO_(4)-Na型水。水化学成分聚类分析结果表明萨拉乌苏组与直罗组风化基岩含水层有一定关联度。氢氧同位素特征显示萨拉乌苏组和直罗组风化基岩地下水补给来源相同,直罗组基岩地下水补给来源与两者不同;萨拉乌苏组地下水年龄较小,直罗组基岩地下水年龄相对较老。综合水化学和环境同位素信息,萨拉乌苏组与直罗组风化基岩含水层间水力联系较密切,两者与直罗组基岩含水层间水力联系较差。研究成果将为研究区煤炭开采、地下水合理利用及水害防治提供科学依据。In order to further provide a theoretical basis for groundwater utilization and safe mining in the Shenfu mining area.In this paper,based on the analysis of hydrogeological structure,the hydraulic connection between the Salausu Formation aquifer,the weathered bedrock aquifer of the Zhiluo Formation and the bedrock aquifer of the Zhiluo Formation in the Shenfu mining area is analyzed using a combination of hydrochemistry,multivariate statistics and^(2)H,^(18)O and^(3)H isotope methods.The results show that the pH of all aquifers in the study area is between 7 and 11,which is alkaline water.The average TDS values of groundwater from the Salawusu Formation and the weathered bedrock of the Zhiluo Formation are 294.55 mg/L and 267.72 mg/L,re-spectively,which are freshwater with low mineralization.The average value of TDS in bedrock groundwater of the Zhiluo Formation is 867.35 mg/L,with a high degree of mineralization.The main hydrochemical types of the Salawusu Formation aquifer and the weathered bedrock aquifer of the Zhiluo Formation are both HCO_(3)−Ca type water,and the main hydrochemical types of the bedrock aquifer of the Zhiluo Formation are HCO_(3)−Na type water and HCO_(3)·SO_(4)−Na type water.The results of the clustering analysis of water chemistry indicate that the Salawusu Formation aquifer has a certain degree of correlation with the weathered bedrock aquifer of the Zhiluo Formation.The hydrogen and oxygen isotope signatures show that the groundwater recharge sources of the weathered bedrock of the Salawusu Formation and the Zhiluo Formation are the same,and the groundwater recharge sources of the bedrock of the Zhiluo Formation are different from both.The age of groundwater was calculated based on the tritium content in groundwater of each aquifer,and it was concluded that the age of groundwater of the Salawusu Formation is small and the age of groundwater of the bedrock of the Zhiluo For�mation is relatively old.Comprehensive water chemistry and environmental isotope information show that the

关 键 词：水力联系 水化学特征 环境同位素 地下水 神府矿区 

分 类 号：P641[天文地球—地质矿产勘探]