广东清远盆地地下水水文地球化学及流场特征  

Hydrogeochemical Characterization and Flow Field of Groundwater in the Qingyuan Basin of Guangdong Province,China

作　　者：姜守俊 许兰芳 倪泽华 杨宏宇 涂世亮 JIANG Shou-Jun;XU Lan-Fang;NI Ze-Hua;YANG Hong-Yu;TU Shi-Liang(Guangdong Geological Survey Institute,Guangzhou 510080,Guangdong,China)

机构地区：[1]广东省地质调查院,广东广州510080

出　　处：《华南地质》2023年第4期672-685,共14页South China Geology

基　　金：广东省地质勘查与城市地质专项(2022-20,2023-31)。

摘　　要：清远盆地水文地质条件复杂,面积占比过半的岩溶含水层流场尚未厘清。结合地下水钠(Na^(+))、钾(K^(+))、钙(Ca^(2+))、镁(Mg^(2+))、氯离子(Cl^(-))、硫酸根(SO_(4)^(2−))、碳酸根(CO_(3)^(2-))、重碳酸根(HCO_(3)-)、硝酸根(NO_(3)(-))、总溶解固体(TDS)、氢同位素(δD)、氧同位素(δ^(18)O)和氚浓度(^(3)H)共13项测试指标和钻孔数据,本文分析了清远盆地水文地球化学特征,确定了清远盆地岩溶地下水流场特征。结果表明:北江盆地地下水补给来源为大气降水和地表水;岩溶水水化学类型以HCO_(3)-Ca型水为主,盆地周边低山丘陵地区水化学类型以HCO_(3)·Cl^(-)Na(Ca·Na)、HCO_(3)·Cl^(-)Ca·Na(Mg)为主。根据地下水补给和径流范围、流场平面形态、埋藏条件等,将清远盆地地下水系统划分为四个区:北江北岸、东南岸、西南岸和西北岸等。这些区块岩溶水在补给区—径流区—排泄区水文地球化学分带特征明显,阳离子交换反应强度和矿化度逐渐增强,TDS总体以北江和滨江为中心,呈现出向四周递减的趋势,表明从山前补给区到主干流排泄区径流速度逐渐减缓。北江西南岸中部地带岩溶水TDS值异常高,表明该地带可能为滞留区。通过以上对清远盆地地下水流场特征的分析,建立了清远盆地岩溶水流场概念模型,为地下水资源管理、地下水污染防治等提供了基础地质依据。The hydrogeological conditions of the Qingyuan Basin are complex.The flow field of the karst drilling data and aquifers in the basin,which accounts for more than half of the area,has not yet been clarified.Combined with drilling data and 13 test indexes,including sodium(Na^(+)),potassium(K^(+)),calcium(Ca^(2+)),magnesium(Mg^(2+)),chloride(Cl−),sulfate(SO_(4)^(2−)),carbonate(CO_(3)^(2-)),bicarbonate(HCO_(3)^(−)),nitrate(NO_(3)(-)),total dissolved solids(TDS),hydrogen isotope(δD),oxygen isotope(δ^(18)O),and tritium concentration(^(3)H),the hydrogeochemical characteristics of the Qingyuan Basin have been analyzed,and the characteristics of the karst groundwater flow field in the Qingyuan Basin have been identified.The results show that the sources of groundwater recharge in the Beijiang Basin are atmospheric precipitation and surface water.The hydrochemistry of karst water is dominated by HCO_(3)-Ca type,while the main water types of low-hill areas around the basin are HCO_(3)·Cl^(-)Na(Ca·Na)and HCO_(3)·Cl^(-)Ca·Na(Mg).According to the range of groundwater recharge and runoff,the planar morphology of the flow field,and burial conditions,the groundwater system in the Qingyuan Basin is divided into four zones:the north bank,the southeast bank,the southwest bank and the northwest bank of the Beijiang River.The hydrogeochemical zoning characteristics of karst water in these areas are obvious in the recharge zone-runoff zone-discharge zone.The intensity of cation-exchange reaction and mineralization gradually increases,and the overall TDS values decrease from the Beijiang River and Binjiang River to the surrounding areas,indicating a gradual slowdown trend of runoff from the piedmont recharge zone to the mainstream discharge zone.The abnormally high TDS value of karst water in the middle of the southwest bank of the Beijiang River indicates that this zone would be a stagnant zone.Based on the analysis above of the characteristics of the groundwater flow field in the Qingyuan Basin,a conceptual model of the ka

关 键 词：岩溶水 水文地球化学特征 流场 氢氧同位素 清远盆地 

分 类 号：P592[天文地球—地球化学]