鄂尔多斯盆地北洛河上游河水基流来源的识别  

Identification of base flow source of the upper reaches of Beiluo river in Ordos Basin

作　　者：吴玺[1] 韩双宝[1] 李海学[1] 杨瀚文 魏世博 马涛 袁磊 WU Xi;HAN Shuangbao;LI Haixue;YANG Hanwen;WEI Shibo;MA Tao;YUAN Lei(Center for Hydrogeology and Environmental Geology Survey,China Geological Survey,Baoding 071051;Xi’an Center of Mineral Resources Survey,China Geological Survey,Xi’an 710100,China)

机构地区：[1]中国地质调查局水文地质环境地质调查中心,保定071051 [2]中国地质调查局西安矿产资源调查中心,西安710100

出　　处：《干旱区资源与环境》2021年第10期161-168,共8页Journal of Arid Land Resources and Environment

基　　金：渭河流域水文地质调查(DD20190333);重点地区地下水流场调查(西安矿产中心)(DD20211563);黄河流域水文地质调查工程共同资助。

摘　　要：基流是地下水补给河川的水量,补给过程平缓且持续时间长,可保障枯水期河川不断流。北洛河上游白垩系环河组与洛河组的潜水、承压水对河水基流量均有贡献,文中综合运用水位对比、径流实测、水化学同位素分析、基流分割等方法识别基流的主要贡献组分并计算基流量。结果表明:1)白垩系潜水位一般高于河水位,潜水补给河水;环河组、洛河组承压水位分别在芦子坪至金鼎镇河段、芦子坪至旦八镇河段高出河水位,至隔水顶板被揭穿后,承压水才补给河水。2)实测北洛河源头、白垩系环河组与洛河组地层分界处、白垩系与侏罗系地层分界处的枯水期流量分别为0.003m^(3)/s、1.764m^(3)/s、3.671m^(3)/s,沿流程逐渐增加,表明河水不断接受地下水补给;河水的TDS、Cl^(-)含量的变化趋势与白垩系地下水一致,印证白垩系地下水向北洛河排泄,不断稀释河水。3)分析地下水^(14)C、氘氧同位素数据,认为北洛河侵蚀基准面以下的白垩系地下水循环交替不积极,侵蚀基准面以上的潜水为北洛河基流的主要组分。4)采用基流分割法分析刘家河水文站丰水年(1977年)、平水年(1979年)、枯水年(1962年、2015年)的径流数据,得出侵蚀基准面以上白垩系潜水向北洛河的排泄量分别为1.34×10^(8)m^(3)、1.23×10^(8)m^(3)、0.93×10^(8)m^(3)、0.69×10^(8)m^(3)。Base flow is the amount of water that groundwater recharges rivers.The recharge process is gentle and lasts for a long time,which can ensure the continuous flow of rivers in dry season.The phreatic water and confined water of the Cretaceous Huanhe formation and Luohe formation in the upper reaches of Beiluo River contribute to the base flow.In this paper,the main contributing components of the base flow are identified and the base flow is calculated by using the methods of water level comparison,runoff measurement,hydrochemical isotope analysis and base flow separation.The results show that:1)The Cretaceous phreatic water level is generally higher than the river water level,and the phreatic water recharges the river water;the confined water level of Huanhe formation and Luohe formation is higher than the river water level in Luziping-Jinding town and Luziping-Danba town,respectively,and the confined water recharges the river only after the upper confining bed is exposed.2)The measured discharge at the source of Beiluo River,the boundary between Cretaceous Huanhe formation and Luohe formation,and the boundary between Cretaceous and Jurassic are 0.003 m^(3)/s,1.764 m^(3)/s and 3.671 m^(3)/s,respectively,during dry season,which increase gradually along the flow process,indicating that the river water is continuously recharged by groundwater,and the variation trend of TDS and Cl^(-)content of the river water is consistent with that of the Cretaceous groundwater,which confirms that the Cretaceous groundwater discharges to the Beiluo river and continuously dilutes the river water.3)Based on the analysis of^(14)C,D and O isotope data of groundwater,it is considered that the groundwater circulation of Cretaceous system below the erosion base level is not active,and the phreatic water above the erosion base level is the main component of the base flow of Beiluo River.4)The runoff data of wet year(1977),normal year(1979)and dry year(1962,2015)of Liujiahe hydrological station are analyzed by base flow separation.The dischar

关 键 词：鄂尔多斯盆地 北洛河 白垩系含水系统 氘氧同位素 基流分割 

分 类 号：P641[天文地球—地质矿产勘探]