冀东平原馆陶组地热流体水化学成分和H-O同位素组成特征及其地质意义  

Hydrochemistry and H-O Isotopic Constraints of Geothermal Fluids in the Guantao Formation in the Eastern Hebei Plain:Implications for Geothermal Reservoir Dynamics

作　　者：徐一鸣 李傲宇 程立群 杜立新 张艳帅 郝文辉 刘亮 XU Yiming;LI Aoyu;CHENG Liqun;DU Lixin;ZHANG Yanshuai;HAO Wenhui;LIU Liang(The Eighth Geological Brigade of Hebei Bureau of Geology and Mineral Resources Exploration,Qinhuangdao,Hebei 066000,China;Hebei Baodi Construction Engineering Corporation,Ltd,Qinhuangdao,Hebei 066000,China;China National Geological&Mining Corporation,Beijing 100029,China;The Seventh Geological Brigade of Hebei Bureau of Geology and Mineral Resources Exploration,Xiong’an,Hebei 071700,China;School of Water Resources and Environment,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]河北省地质矿产勘查开发局第八地质大队,河北秦皇岛066000 [2]河北宝地建设工程有限公司,河北秦皇岛066000 [3]中国地质矿业有限公司,北京100029 [4]河北省地质矿产勘查开发局第七地质大队,河北雄安071700 [5]中国地质大学(北京)水资源与环境学院,北京100083

出　　处：《现代地质》2025年第2期429-439,共11页Geoscience

基　　金：河北省自然资源厅项目“冀东平原区地热资源勘查”(2017020)。

摘　　要：冀东平原新近系馆陶组热储为碎屑岩类孔隙型层状热储,地热地质条件优越。为了科学保护、合理利用该地热资源,本文对冀东平原不同地质构造单元所采集的16个馆陶组地热水样开展了化学成分和H-O同位素组成分析。结果显示,冀东平原馆陶组地热水pH值范围7.78~8.62、矿化度722.3~2619 mg/L、水化学类型主要有HCO_(3)·SO_(4)-Na、HCO_(3)·Cl-Na、SO_(4)·Cl-Na型;热水中F^(-)、SiO_(2)、溶解性总固体、锶、锌、溴、碘、铁、锰、偏硼酸等含量较高,但与西藏羊八井和搭格架相比,地热水中一些与岩浆热液活动相关的元素(如F、B、As、Li等)含量要低得多。H-O同位素特征显示,地热水中δD值为-71‰~-73‰,δ^(18)O值为-7.6‰~-9.8‰,地热水补给高程800~1300 m,总体径流方向由西北向东南,地热水与上覆浅部地层水联系不密切,主要受侧向同层径流补给及古生界奥陶系热流体的顶托补给,为深层承压水,属深循环加热成因的地下热水。燕山地区山地大气降水在重力的作用下沿断裂构造向下运移,并向东南径流,地下水被来自地壳深部的热不断加温,水-岩反应逐渐剧烈,溶滤作用,导致热水中矿物质含量显著增加。随着循环深度和距离的增加,地热水赋存环境越来越封闭,水体更新速率逐渐降低,地热水发生脱硫酸作用,同时与下伏深部热储地热流体发生混合作用,主要离子也随之发生了变化。本研究为理解馆陶组地热水的形成与演化过程提供了科学依据。The Neogene Guantao Formation geothermal reservoir in the Eastern Hebei Plain represents a clastic porous layered heat reservoir characterized by superior geothermal geological conditions.To facilitate the scientific conservation and rational utilization of these geothermal resources,this study presents comprehensive analysis of the chemical and H-O isotopic compositions of 16 geothermal water samples collected from various geological units within the Eastern Hebei Plain.Experimental results reveal that the primary hydrochemical types of the Guantao Formation geothermal water are HCO_3· SO_4-Na,HCO_3·Cl-Na,SO_4·Cl-Na,with pH values ranging from 7.78 to 8.62 and salinity levels between 722.3 and 2619 mg/L.The geothermal water exhibits elevated concentrations of F~-,SiO_2,TDS,Sr,Zn,Br,I,Fe,Mn,and HBO_2.However,concentrations of certain elements associated with magmatic hydrothermal activities(such as F,B,As,Li,etc.) are significantly lower compared to those found in Yangbajing and Dagejia in Tibet.H-O isotopic analysis indicates δD values ranging from-71‰ to-73‰ and δ~(18)O values from-7.6‰ to-9.8‰,suggesting a recharge elevation of 800 to 1300 meters.The geothermal water primarily flows from northwest to southeast,with minimal interaction with overlying shallow strata water.It is predominantly recharged by lateral flow within the same layer and the upward migration of Ordovician hot fluids from the Paleozoic erathem,classifying it as deep-circulation heated groundwater.Atmospheric precipitation from the Yanshan area percolates downward along fault structures under gravitational force,flowing southeastward.As the groundwater is progressively heated by deep crustal thermal sources,water-rock interactions intensify,leading to a significant increase in mineral content.With increasing circulation depth and distance,the geothermal water environment becomes more confined,resulting in a gradual reduction in water renewal rates.Desulfation processes occur within the geothermal water,which also mixes with under

关 键 词：水化学特征 同位素特征 地热水 馆陶组 冀东平原 

分 类 号：P641.3[天文地球—地质矿产勘探]