张掖-民乐盆地ZYDR3井地热流体氦同位素的指示  

INDICATION OF HELIUM ISOTOPES IN UNDERGROUND HOT WATER OF ZYDR3GEOTHERMAL WELL INZHANGYE-MINLEBASIN

作　　者：尹政 何剑波 张旭儒 张玲 汪嘉逸 刘希尧 YIN Zheng;HE Jian-bo;ZHANG Xu-ru;ZHANG Ling;WANG Jia-yi;LIU Xi-yao(Institute of Hydrogeology and Engineering Geology,Gansu Provincial Bureau of Geology and Mineral Exploration and Development,Zhangye 734000,China;Key Laboratory of Grounder Water Engineering and Geothermal Resources in Gansu Province,Lanzhou 730050,China)

机构地区：[1]甘肃省地矿局水文地质工程地质勘察院,甘肃张掖734000 [2]甘肃省地下水工程及地热资源重点实验室,甘肃兰州730050

出　　处：《甘肃地质》2024年第1期53-58,共6页Gansu Geology

基　　金：甘肃省2022年省级基础地质调查项目“张掖—民乐盆地地热及氦气资源赋存规律研究”;甘肃省自然资源厅科技项目“张掖-民乐盆地地温场特征研究(202232)”;甘肃省地矿局2021年度创新资金项目“张掖-民乐盆地地热资源勘查开发条件研究”(2021CX08)。

摘　　要：张掖—民乐盆地ZYDR3地热井地热流体中富含水溶性气体,其中氦气含量占水溶性气体含量的1.198%。通过对ZYDR3地热井地热流体氦同位素的分析测试,其3He/4He的值R(4.40×10^(-8))远小于大气3He/4He的值Ra(1.40×10^(-6)),认为该地热井地热流体中氦气以壳源氦为主,混合有微量的幔源氦。本文分析计算了热储层的热导率和井温梯度,并以此估算的大地热流值为69.23 mW/m^(2),略高于中国大陆地区平均热流值61.50 mW/m^(2),显示该地热井附近具有较好的热流状态;根据氦同位素4He、3He通量与壳、幔热流的相关关系,分析大地热流中主要为壳源热流,约占85.50%,幔源热流仅占14.50%。研究方法丰富了该区地热系统理论,同时为该区地热资源开发利用提供了一定的理论支撑。The geothermal fluid of the ZYDR3 geothermal well in Zhangye-Minle Basin is rich in water-soluble gases,among this the content of helium gas accounts for 1.198% of water-soluble gas.Through the analysis and test of the helium isotopic of the geothermal fluid in the ZYDR3 geothermal well,the value R(4.40×10^(-8))of 3He/4He is much smaller than the value Ra(1.40×10^(-6))of atmospheric 3He/4He,it is suggesting that the helium in the geothermal fluid in ZYDR3 geothermal well is mainly shell helium,mixed with a trace amount of mantle-derived helium.The thermal conductivity and well temperature gradient of the thermal reservoir are analyzed and calculated in this paper,and the estimated terrestrial heat flow value is 69.23 mW/m^(2),which is slightly higher than the average heat flow value of 61.50 mW/m^(2)in China's Mainland,which indicates that this region has a good heat flow state.The analysis shows that the main terrestrial heat flow is shell source heat flow accounting for about 85.50%,and a small amount of mantle derived heat flow accounted for about 14.50%.The research method enriches the theory of geothermal system and at the same time provides some theoretical support for the development and utilization of geothermal resources in this area.

关 键 词：HE同位素 壳幔热流比值 热储温度 地温梯度 张掖—民乐盆地 

分 类 号：P314[天文地球—固体地球物理学] P641[天文地球—地球物理学]