砂岩孔隙热储地温场水化学场特征及地热水富集机理——鲁北馆陶组热储典型案例  

Hydrochemical features of geothermal reservoir geotemperature field in sandstone porosity and enrichment mechanism of geothermal water:a case study of geothermal reservoir of Guantao Formation in the Lubei

作　　者：杨询昌 康凤新 王学鹏 付庆杰[4] 刘志涛 YANG Xunchang;KANG Fengxin;WANG Xuepeng;FU Qingjie;LIU Zhitao(Shandong Provijnicial Lubei Geo-engineering Exploration Institute ,Dezhou,Shandong,253015;Shandong Provincial Bureau of Geology and Mineral Resources , Jinan,250013;Shandong Provincial Technology Research Center of Geological Exploratiion Engineering ,Jiinan, 250013;Shandong Provincial South Shandong Oeo-engineerijig Exploration Institute , Yanzhou ,Shandong, 272100)

机构地区：[1]山东省鲁北地质工程勘察院,山东德州253015 [2]山东省地质矿产勘查开发局,济南250013 [3]山东省地质勘查工程技术研究中心,济南250013 [4]山东省鲁南地质工程勘察院,山东兖州272100

出　　处：《地质学报》2019年第3期738-750,共13页Acta Geologica Sinica

基　　金：山东省地质科研项目(编号鲁地字[2016]28号;鲁地字[2017]23号)资助成果

摘　　要：鲁北平原不同构造单元,具有不同温度、矿化度、特殊化学成分、富水性的地热资源。其中馆陶组热储是区内资源最丰富、开采利用程度最高、规模最大,为最具经济开采价值的热储。正确认识其地温场、水化学场特征及地热水富集机理,成为目前人们最为关心的问题。本文根据对馆陶组热储盖层地温梯度、热储温度变化特征的分析,结合地质构造条件,揭示了地温场温度受断裂构造影响,高温区主要分布在武城-高唐-陵县、宁津-庆云、沾化-孤岛、高青-博兴等凸起区与断裂交汇部位。区内馆陶组地热水化学类型以Cl-Na为主,其次为Cl·SO_4-Na及SO_4·Cl-Na型,矿化度4.07～18.52g/L,pH值7.14～8.1,地热水中含有大量人体健康所需的微量元素。分析认为,区内馆陶组地热水成因为大气降水,蒙脱石向绿泥石转变是地热水中贫钾、贫镁原因,馆陶组热储地热水总体流向为西南流向东北,在各县市城区地热水由四周向城区漏斗中心运移。本文根据地热钻探揭露馆陶组底砾岩深度、厚度及地热井水位、单井涌水量等大量数据的分析,揭示了鲁北平原馆陶组地热水古沉积相环境,并划分出两个大的古河道带:即临清—武城—德州—陵县一线古河道带和沾化—河口—仙河一线古河道带。前者后期受南部高唐凸起和东部埕子口-宁津潜断隆控制,在德州—陵县一带形成了范围较大、岩性颗粒较粗、厚度较大的冲洪积扇区;后者主要受西北部刁口潜凸起、义和庄潜凸起与南部无棣潜凸起控制,在河口—孤岛—仙河一带形成了较大范围岩性颗粒较粗、厚度较大的冲洪积扇区。在下游受陈庄凸起、青坨凸起影响,将古河道带分叉为两部分,南部古河道带分布在利津—东营一带。地热水富水规律与古河道带一致,富水区主要分布在两个古河道带区域,单井涌水量一般大于85m^3/h,且距古河道带越近Under the effect of tectonic environment, Lubei plain formed different tectonic units, which contain water-rich geothermal resources with different temperature, salinity, and special chemical composition. Among them, the Guantao Formation is of the most abundant geothermal resources. It has been extensively utilized and has the biggest value of economic exploitation. Correctly understanding the geo-temperature field and hydrochemical field as well as mechanism of geothermal water accumulation has become a major issue. The analysis of the cap rock geothermal gradient of geothermal reservoir and reservoir temperature variation characteristics in the Guantao Formation, combined with the geological conditions, shows that geo-temperature field is controlled by tectonic structure and faults, and relatively high temperature zones are distributed mianly at the convergent areas of uplifts and faults, such as along Wucheng-Gaotang-Lingxian County, Ningjin-Qingyun, Zhanhua-Gudao, Gaoqing-Boxing, etc. The geothermal water types of the Guantao Formation in the study area change from SO4·Cl-Na to Cl-Na, with the mineralization content changing form 4.07 g/L to 18.52 g/L and pH ranging from 7.14 to 8.1.In addition, geothermal water contains plenty of trace elements, which are essential to human health.The change of montmorillonite to chlorite is due to poor potassium and poor magnesium of geothermal water. Geothermal water of the Guantao Formation flows generally from southwest to northeast, but flows from outer part to the center of water table depression cone in urban areas. Our analyses suggest that the origin of Guantao Group geothermal water is the atmospheric precipitation. Based on integrated analyses of depth and thickness of basal conglomerate of the Guantao Formation, as well as geothermal well water level and single well yield, this study reveals the paleo-sedimentary facies and depositional environments of the Guantao Formation in the Lubei plain, and two ancient river channels are divided, i.e. Linqing-Wucheng-Dez

关 键 词：馆陶组 地温梯度 地热水 古河道带 鲁北平原 

分 类 号：P314[天文地球—固体地球物理学]