赣南寻乌—石城断裂带温泉流体地球化学特征  

Geochemical characteristics of hot spring fluids in the Xunwu-Shicheng fault zone of southern Jiangxi

作　　者：肖富强 邹勇军 章双龙 祁星 肖卫东 XIAO Fuqiang;ZOU Yongjun;ZHANG Shuanglong;QI Xing;XIAO Weidong(Jiangxi Province Key Laboratory of Exploration and Development of Critical Mineral Resources,Nanchang,Jiangxi 330001,China;Jiangxi Geological Survey and Exploration Institute,Nanchang,Jiangxi 330001,China;Jiangxi Provincial Coal Geological Exploration and Research Institute,Nanchang,Jiangxi 330001,China)

机构地区：[1]关键矿产资源勘查与开发江西省重点实验室,江西南昌330001 [2]江西省地质调查勘查院,江西南昌330001 [3]江西省煤田地质勘察研究院,江西南昌330001

出　　处：《水文地质工程地质》2025年第2期203-216,共14页Hydrogeology & Engineering Geology

基　　金：江西省地质局青年科学技术带头人培养计划项目(2022JXDZKJRC05);江西省地质局科技基金项目(20200107)。

摘　　要：寻乌—石城断裂带是赣南东部发育的一条NNE向深大断裂带,温泉发育密集且地震活动频繁,以往关于其温泉流体特征及演化机制研究甚少,制约了温泉资源的可持续开发利用。为了揭示该断裂带温泉流体地球化学特征及其成因和来源,更好地开展地热资源勘查研究,采集了断裂带上9组温泉气、水样品,采用分光光度法、色谱法、质谱法等进行了水化学组成、气体组分、同位素分析。结果表明:(1)寻乌—石城断裂带温泉水化学类型主要为HCO_(3)·SO_(4)—Na·Ca型和HCO_(3)—Na型;温泉是大气降水沿断裂带渗入深部热储结构加热形成;温泉水为水岩作用未达到平衡的未成熟水,通过SiO_(2)温标估算的热储温度在99~143℃之间。(2)温泉气体组分以CO_(2)和N_(2)为主,普遍含有He;CO_(2)主要是无机幔源成因,He以壳源成因为主、幔源成因为辅,幔源CO_(2)、He具有显著成因联系,为断裂带沟通深部流体上涌形成。(3)在寻乌—石城断裂带地幔深源流体异常释放作用下,热储温度、幔源气体参数等温泉流体特征与构造和地震活动性有较好的对应关系,断裂带南段是探寻中高温地热资源的有利区。研究结果对指导寻乌—石城断裂带下一步地热资源勘探具有重要意义。The Xunwu-Shicheng fault zone,located in the eastern part of southern Jiangxi,is a NNE-trending deep fault zone characterized by dense geothermal hot spring activity and frequent seismic events.However,limited research on the characteristics and evolutionary mechanisms of its hot spring fluids has hindered the sustainable development and utilization of geothermal resources.To reveal the geochemical characteristics and origin of hot spring fluids in the fault zone to support the geothermal resource exploration,hot spring water samples and gas samples from nine hot springs were collected.Water chemical composition,gas composition,and isotope analysis of the hot springs were tested by spectrophotometry,chromatography,mass spectrometry,etc.The results show that the hydrochemical types of hot springs in the Xunwu-Shicheng fault zone are mainly HCO_(3)·SO_(4)-Na·Ca and HCO_(3)-Na.The hot springs are formed by the heating of precipitation infiltrating deep thermal storage structures along fault zones.The hot spring water is immature water whose water-rock interaction has not reached equilibrium,and the reservoir temperature is estimated to be 99-143℃ by SiO_(2) geothermometer.The gas components in hot springs are mainly CO_(2) and N2,with traces of He.CO_(2) is mainly derived from inorganic mantle sources,while He originates predominantly from crust,with a secondary contribution mantle.Mantle-derived CO_(2) and He have significant genetic connections,formed by the upwelling of deep fluids connected by the fault zones.Under the abnormal release of deep mantle fluids in the Xunwu-Shicheng fault zone,the characteristics of hot spring fluids such as thermal storage temperature and mantle gas parameters have a good correspondence between tectonic and seismic activity.The southern section of the fault zone is a favorable area for exploring medium-high temperature geothermal resources.This study provides valuable insights for guiding futher of hot spring resource exploration in the Xunwu-Shicheng fault zone.

关 键 词：寻乌—石城断裂带 温泉流体 水化学组成 气体化学组成 同位素 

分 类 号：P314[天文地球—固体地球物理学]