采煤驱动下晋东大型煤炭基地地下水循环演变特征——以辛安泉域为例  

Characteristics of groundwater circulation and evolution in Jindong large coal base driven by coal mining:An example of Xin’an spring area

作　　者：李向全[1,3] 张春潮 侯新伟[1,3] LI Xiangquan;ZHANG Chunchao;HOU Xinwei(Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geosciences,Shijiazhuang 050061,China;Chinese Academy of Geosciences,China University of Geosciences,Beijing 100083,China;Key Laboratory of Groundwater Science and Engineering,Ministry of Natural Resources,Shijiazhuang 050061,China)

机构地区：[1]中国地质科学院水文地质环境地质研究所,河北石家庄050061 [2]中国地质大学(北京)中国地质科学院,北京100083 [3]自然资源部地下水科学与工程重点实验室,河北石家庄050061

出　　处：《煤炭学报》2021年第9期3015-3026,共12页Journal of China Coal Society

基　　金：中国地质调查局地质调查资助项目(DD20160296,DD20190252);中国地质科学院基本科研业务费资助项目(JYYWF20180401)。

摘　　要：晋东煤炭基地水资源相对短缺,生态环境脆弱,随着煤炭资源的大规模开采和人类活动加剧,区域地下水循环特征演变剧烈。以晋东煤炭基地辛安泉域为典型研究区,系统研究了采煤驱动下地下水循环演变特征。通过建立泉流量与矿井涌水量、岩溶地下水开采量和大气降水间的多元相关性分析,揭示了岩溶大泉衰减机制及主控因子;通过地表径流切割和氢氧稳定同位素组成混合比例计算,识别了不同水体间的相互转化关系和矿井水的水源组成;结合区域水文地质条件、水化学和稳定同位素特征,构建了采煤影响下的地下水循环模式。研究结果表明:①辛安泉域岩溶大泉流量和岩溶地下水位总体呈下降趋势,1956—2017年泉流量衰减幅度达75%,1972—2017年岩溶地下水位下降最大达29.8 m;且均呈阶段性变化特征,表现为1956—1976年、1977—2002年和2003—2017年3个阶段分别为波动稳定期、快速下降期和缓慢下降期。②矿区东部煤炭开采对岩溶水影响强烈,主要影响途径是采煤活动造成岩溶水补给径流区的上覆含水层结构严重破坏和地表径流量衰减,导致岩溶水补给量减小。随着煤炭开采向西扩展,煤层埋深加大,岩溶水为深埋滞缓区,煤炭开采对其影响减弱。③岩溶大泉流量衰减和地下水位下降的主控因子为矿井涌水量,在快速下降阶段,岩溶水开采也是泉流量衰减和水位下降的重要影响因素。④同位素计算表明,矿井水水源构成主要为裂隙水,其次为孔隙水。地表水渗漏和孔隙水越流是岩溶水的重要补给来源,采煤直接影响地表径流量和孔隙水含水层,进而间接影响岩溶地下水位和岩溶大泉流量。⑤泉域采煤条件下的地下水循环模式可划分为浅部、深部和局部地下水流系统。局部地下水流系统主要受采煤影响,表现为地下水向采空区集中排泄。Jindong large coal base is very short of water resources and its ecological environment is fragile.With the large-scale coal mining and the intensification of human activities,the characteristics of regional groundwater circulation have changed drastically.Taking Xin’an spring area of Jindong coal base as an example,in view of the characteristics of groundwater circulation driven by coal mining in this area,the correlation and statistical analysis were used to study the effects of coal mining on the regional water environment.By establishing a multivariate correlation analysis between spring flow and mine water drainage,karst groundwater exploitation and precipitation,the attenuation mechanism of karst spring and main control factors were revealed.Based on the surface runoff cutting and calculation of the mixing ratio of hydrogen and oxygen stable isotope,the interaction between different water bodies and the source of mine water were identified.Combined with the characteristics of regional hydrogeological conditions,hydrochemistry and stable isotope,the pattern of groundwater circulation under the influence of coal mining was constructed.The results showed that:①The karst spring flow and karst water level of Xin’an spring area from 1956 to 2017 showed a general downward trend,both of which showed periodic change.The attenuation rate of karst springs flow reached 75%from 1956 to 2017 and karst water level dropped by 29.8 m from 1972 to 2017.The three stages of 1956—1976,1977—2002 and 2003—2017 were characterized by steady fluctuation,substantial decrease and slight decrease.②Coal mining in the east of the mining area had a strong influence on karst groundwater.The coal mining activity,as main influence way,has severely damaged the structure of the overlying aquifer in the karst water runoff area and caused the attenuation of surface runoff,resulting in a decrease in the amount of groundwater recharge.As coal mining expanded westward,the burial depth of coal seam was increased and karst water was loc

关 键 词：采煤驱动 煤炭基地 保水采煤(保水开采) 地下水循环 演变特征 辛安泉域 

分 类 号：TD74[矿业工程—矿井通风与安全]