鄂尔多斯盆地北部直罗组地下水地球化学特征及其指示意义  

Geochemical characteristics of groundwater about Zhiluo Formation in the northern Ordos Basin and its indicative significance

作　　者：孙魁 范立民 马万超 陈建平 彭捷 张鹏华 高帅 李成 苗彦平 王宏科 SUN Kui;FAN Limin;MA Wanchao;CHEN Jianping;PENG Jie;ZHANG Penghua;GAO Shuai;LI Cheng;MIAO Yanping;WANG Hongke(Key Laboratory of Mine Geological Hazards Mechanism and Control,MNR/Shaanxi Institute of Geo-Environment Monitoring,Xi’an710054,China;School of Mines,China University of Mining and Technology,Xuzhou 221116,China;Hongliulin Mine of Shaanxi Coal and Chemical Industry Group Co.,Ltd.,Yulin 719000,China;Northern Shaanxi Mining Co.,Ltd.,of Shaanxi Coal Group,Yulin 719000,China)

机构地区：[1]陕西省地质环境监测总站自然资源部矿山地质灾害成灾机理与防控重点实验室,陕西西安710054 [2]中国矿业大学矿业工程学院,江苏徐州221116 [3]陕煤集团神木红柳林矿业公司,陕西榆林719000 [4]陕西陕煤陕北矿业有限公司,陕西榆林719000

出　　处：《煤炭学报》2024年第4期2004-2020,共17页Journal of China Coal Society

基　　金：国家重点研发计划资助项目(2019YFC1805404);陕西煤业化工集团有限公司2020年度重点科研资助项目(2020SMHKJ-B-J-27);陕西省自然科学基础研究计划-陕煤联合基金重点资助项目(2019JLZ-03)。

摘　　要：煤矿水害是陕北侏罗纪煤田的主要灾害,直罗组地下水是主要突水水源之一。为研究鄂尔多斯盆地北部直罗组地下水地球化学特征及其指示意义,借助Durov图、Piper三线图、Gibbs图、Stiff图以及主成分分析等手段,深入研究直罗组地下水地球化学特征,阐释其对直罗组与上覆含水层之间水力联系及地下水径流条件的指示意义。结果表明:自西部正常基岩区至东部风化基岩区,直罗组地下水pH以及TDS、K^(+)+Na^(+)、SO_(4)^(2-)、Cl^(-)质量浓度均呈现出逐渐减小的趋势。直罗组地下水水化学类型存在一定差异,西部直罗组埋藏较深区域,地下水水化学类型以SO_(4)-Na型、SO_(4)·Cl^(-)Na型和HCO_(3)·SO_(4)-Na型为主,向东至直罗组基岩风化区,地下水类型过渡为HCO_(3)-Ca型和HCO_(3)-Ca·Mg型等。直罗组地下水水化学形成受岩石风化作用、交替吸附作用、脱硫酸作用以及溶滤作用的控制。氢氧同位素和水化学特征对含水层之间水力联系具有明显的指示作用,氢氧同位素、典型钻孔地下水水化学离子浓度和区域地下水水化学特征分析表明,研究区西部直罗组正常基岩地下水与洛河组、萨拉乌苏组地下水基本不存在水力联系;东部直罗组风化基岩与萨拉乌苏组地下水水力联系紧密。卤族元素Cl^(-)对直罗组地下水径流条件指示作用明显,研究区西部直罗组正常基岩地下水径流滞缓,地下水以静储量为主;而在基岩风化区,由于直罗组风化基岩孔隙、裂隙发育,储水性和渗透性明显增强,并与第四系地下水发生了强烈的混合作用,地下水径流强度大,地下水以动储量为主。Coal mine water disaster is the main disaster of the Jurassic coalfield in the northern Shaanxi and the groundwa-ter of the Zhiluo Formation is one of the main water inrush sources.Using the Durov diagram,Piper three-line diagram,Gibbs diagram,Stiff diagram and principal component analysis method,the geochemical characteristics of the Zhiluo Formation groundwater in the northern Ordos Basin and its indicative significance were investigated in this study.Also,it studied the geochemical characteristics of groundwater and explains its significance for the hydraulic connection between the Zhiluo Formation and overlying aquifer and the groundwater runoff conditions.The results show that the concentra-tions of the pH,TDS,K^(+)+Na^(+),SO_(4)^(2-)and Cl^(-)show a decreasing trend about the Zhiluo Formation groundwater from the western normal bedrock area to the eastern weathered bedrock area.And there are some differences about the Zhiluo Formation groundwater chemical types.For the deep buried area of the Zhiluo Formation in the west,the hydrochemical types of groundwater are mainly SO_(4)-Na type,SO_(4)·Cl^(-)Na type and HCO_(3)·SO_(4)-Na type.For the bedrock weathering area of the Zhiluo Formation in the east,the groundwater type transitions to HCO_(3)-Ca type and HCO_(3)-Ca·Mg type.The hydrochemical formation of the Zhiluo Formation groundwater is controlled by rock weathering,alternating adsorption,desulfuration and leaching.Hydrogen isotope and oxygen isotope and hydro-chemical characteristics have obvious indicat-ive effects on the hydraulic connection between aquifers.The analysis of hydrogen isotope and oxygen isotope,chemical ion concentration of typical borehole groundwater and regional groundwater hydro-chemical characteristics shows that there is no hydraulic connection between the normal bedrock groundwater of the Zhiluo Formation and the groundwater of the Luohe Formation and the Salawusu Formation in the western part of the study area.The weathered bedrock groundwa-ter of the Zhiluo Formation in the ea

关 键 词：直罗组含水层 水化学特征 水力联系 地下水径流条件 鄂尔多斯盆地 

分 类 号：TD745[矿业工程—矿井通风与安全]