石城地热带水文地球化学特征与成因分析  

Analysis of hydrogeochemical characteristics and origin in the Shicheng geothermal belt

作　　者：叶海龙 樊柄宏 白细民 陈强 陈锡岳[1] 冯子晋 曹进 YE Hailong;FAN Binghong;BAI Ximin;CHEN Qiang;CHEN Xiyue;FENG Zijin;CAO Jin(Jiangxi Institute of Survey and Design,Nanchang,Jiangxi 330095,China;East China University of Technology,Nanchang,Jiangxi 330105,China)

机构地区：[1]江西省勘察设计研究院,江西南昌330095 [2]东华理工大学,江西南昌330105

出　　处：《地质学报》2023年第1期238-249,共12页Acta Geologica Sinica

基　　金：中国地质调查局地质调查项目(编号12120113077300);江西省重点研发计划“揭榜挂帅”项目(编号20223BBG74005);江西省地质勘查基金项目(编号20120114、20150029、20160006、20160009);江西省地质局科技研究项目(编号2021AA11)联合资助的成果。

摘　　要：石城地热带蕴藏着丰富的地热资源,从水文地球化学角度系统研究其地热水演化机理,对支撑地热带盲区靶区优选和隐伏型地热水的发掘,对推动地热资源的可持续规模化开发利用具有重要意义。本文在充分分析石城地热带地热地质条件的基础上,根据地热水与冷水水化学分析结果,采用Piper三线图、溶质间相关分析、地球化学温标法等手段,对地热水化学特征、矿物元素来源、热储温度与埋藏条件、浅层冷水的混合机制等进行了讨论分析。结果表明,石城地热带所有地热田同属一个地热系统,大气降水在北东部牙梳山中低山区自然入渗补给,深部循环获取幔源大地热流的供热,并与营上岩体富钾花岗岩充分水-岩作用富集K+、SiO2等矿物元素,遇石城断裂阻水后转向南西侧向径流和浅部排泄。地热水水质由HCO_(3)-Ca型向SO_(4)-Na型、SO_(4)·HCO_(3)-Na·Ca型、HCO_(3)-Na·Ca型转化,这种分带性是受深部地热水径流距离、浅部冷水混合比例、上涌途经地层与矿体特征等联合控制的结果。Shicheng is rich in geothermal resources.From the perspective of hydrogeochemistry,we systematically study the evolution mechanism of geothermal water,optimize the target area supporting the blind zone of the geotropics and excavate hidden geothermal water,and promote the sustainable scale of geothermal resources.Development and utilization are of great significance.Based on a full analysis of the geothermal geological conditions of the Shicheng geo-tropical zone,the results of the geothermal and cold water chemical analysis,the Piper three-line diagram,the correlation analysis between solutes,and the geochemical temperature scale method are used to analyze the chemical characteristics and the sources of mineral elements of geothermal water.The source,thermal storage temperature and burial conditions,and the mixing mechanism of shallow cold water were discussed and analyzed.The results show that all the geothermal fields in the Shicheng subtropical zone belong to the same geothermal system.Atmospheric precipitation naturally infiltrates and replenishes in the middle and low mountainous areas of the Yasu Mountain in the northeast.The water-rock interaction enriches mineral elements such as K+,SiO2,and turns to the southwest side to runoff and shallow discharge after encountering the Shicheng fault that blocks water.The quality of geothermal water changes from HCO3-Ca type to SO_(4)-Na type,SO_(4)·HCO3-Na·Ca type,HCO3-Na·Ca type.This zoning is affected by the deep geothermal runoff distance and shallow cold water mixing.The result of joint control of ratio,upwelling path,strata and ore body characteristics.

关 键 词：地热水 地球化学特征 成因模式 热储温度 石城地热带 

分 类 号：P314[天文地球—固体地球物理学]