地质构造控制下地热流体水化学、同位素及循环特征--以蔚县盆地为例  

Hydrochemistry,isotope and circulation characteristics of geothermal fluids controlled by geological structure:A case study of Yuxian Basin

作　　者：李振雄 胡博文 王振华 郭鑫鑫 庾乐彬 张晓幸 LI Zhenxiong;HU Bowen;WANG Zhenhua;GUO Xinxin;YU Lebin;ZHANG Xiaoxing(Land Resources Exploration Center,Hebei Bureau of Geology and Mineral Resources Exploration and Development(Hebei Mining and Geological Disaster Emergency Rescue Center),Heibei Shijiazhuang 050085,China)

机构地区：[1]河北省地质矿产勘查开发局国土资源勘查中心(河北省矿山和地质灾害应急救援中心),河北石家庄050085

出　　处：《中国地质调查》2024年第6期64-75,共12页Geological Survey of China

基　　金：张家口市蔚县地热温泉资源详细调查项目资助。

摘　　要：蔚县盆地地热资源丰富,地质构造繁杂,研究地质构造控制下的地热流体水化学、同位素及循环特征可进一步促进地热开发与利用,以及环首都县市地热温泉康养产业发展。通过结合地下水和大气降水,运用多元统计、相关性及特征系数分析,借助Piper三线图、Na-K-Mg三角图,对蔚县盆地地热流体进行研究。研究结果显示:①地热流体中阳离子以Na^(+)、Ca^(2+)、Mg^(2+)为主,阴离子以HCO_(3)^(-)、SO^(2-)_(4)为主;Ca^(2+)、Mg^(2+)、HCO_(3)^(-)主要源于碳酸盐岩类矿物的溶解;②地热流体中存在阳离子交替吸附作用,作用方向为K+、Na+进入液相,Ca^(2+)、Mg^(2+)进入固相,Na+与Ca^(2+)、Mg^(2+)处于此消彼长、相互抑制的状态;③热储地层封闭性较差,地热流体浓缩程度和变质程度较低,受渗入水及浅表层氧化作用影响显著;地热流体补给来源主要为大气降水,径流路径较短,水循环较快;④热储温度为37.32~57.36℃,蓟县系雾迷山组热储最大循环深度为1715~2640 m,蓟县系高于庄组热储最大循环深度为3291~3337 m,均值为3314 m。研究结果揭示了地质构造作用下水岩相互作用,对研究该地区地热流体水化学演化及动态特征具有一定意义。Yuxian Basin has rich geothermal resources and complex geological structures.The study on the hydro-chemistry,isotope and circulation characteristics of geothermal fluids controlled by geological structures can further promote the development and utilization of geothermal resources and geothermal hot spring health care industry a-round the capital city.By combining groundwater and atmospheric precipitation,and using multivariate statistics,correlation and characteristic coefficient analysis,the authors studied the geothermal fluid in Yuxian Basin using Piper triplex diagram and Na-K-Mg triangle diagram.The results are as follows.①The cations in geothermal fluid are mainly Na^(+),Ca^(2+)and Mg^(2+),and the anions are mainly HCO_(3)^(-) and SO^(2-)_(4).Ca^(2+),Mg^(2+)and HCO_(3)^(-) are mainly derived from the dissolution of carbonate minerals.②A cation alternat adsorption occurred in geothermal fluid,with the action direction of K+,Na+into the liquid phase,and Ca^(2+),Mg^(2+)into the solid phase.Na+and Ca^(2+),Mg^(2+)are in a state of mutual inhibition.③The thermal reservoir formation is poorly sealed,the concentration degree and metamorphism degree of geothermal fluid are low,indicating a significant affection by infiltration water and shallow surface oxidation.The main source of geothermal fluid recharge is atmospheric precipitation,and the runoff path is short with fast water cycle.④The heat storage temperature was 37.32~57.36℃,the maximum circulating depth of heat storage in Wumishan Formation of Jixian System was 1715~2640 m,and the maximum circulating depth of the heat storage in Gaoyuzhuang Formation of Jixian System was 3291~3337 m,with the average value of 3314 m.The interaction between groundwater and rock under geological structure was revealed,which could provide certain guidance in studying the hydrochemical evolution and dynamic characteristics of geothermal fluid in this area.

关 键 词：蔚县盆地 地热流体 水文地球化学 同位素地球化学 循环特征 

分 类 号：P641[天文地球—地质矿产勘探]