东南沿海厦门湾-漳州盆地地热地质特征及干热岩勘查方向  

Geothermal, geological characteristics and exploration direction of hot dry rocks in the Xiamen bay-Zhangzhou basin, southeastern China

作　　者：蔺文静[1,2] 陈向阳 甘浩男[1,2] 岳高凡 LIN Wenjing;CHEN Xiangyang;GAN Haonan;YUE Gaofan(Institute of Hydrogeology and Environmental Geology,CAGS,Shijiazhuang,050061;Technology Inovation Center of Geothermal&Hot Dry Rock Exploitation and Development,MNR;Southern Fujian Geological Brigade,Zhangzhou,Fujian363000)

机构地区：[1]中国地质科学院水文地质环境地质研究所,石家庄050061 [2]自然资源部地热与干热岩勘查开发技术创新中心,石家庄050061 [3]福建省闽南地质大队,福建漳州363000

出　　处：《地质学报》2020年第7期2066-2077,共12页Acta Geologica Sinica

基　　金：中国地质调查项目(编号12120115045901、DD20160191);国家自然科学基金项目(编号41741018);中国地质科学院水文地质环境地质研究所基本科研业务费项目(编号SK201902)联合资助成果。

摘　　要：东南沿海位于欧亚板块与菲律宾板块的俯冲带,构造运动活跃,同时,该区也是我国最主要的高放射性花岗岩分布区,发育大面积的中生代酸性花岗岩体,具有良好的干热岩赋存背景。本文以东南沿海福建厦门湾-漳州盆地为例,在区域地热地质背景研究的基础上,从区域大地热流、地温梯度、热储温度、循环深度以及深部地温场分布等方面系统分析了厦门湾-漳州地区干热岩资源的形成条件,科学评价了本区未来干热岩资源勘查的适宜深度。分析认为,区内平均地温梯度约为18.3℃/km,低于大陆地区平均值;花岗岩体的放射性生热率仅略高于世界范围内的花岗岩放射性生热率的平均值;区内相对高的地表热流值很大一部分来自于地幔热传导,放射性元素生热贡献相对较低,要达到180℃的干热岩开发温度,勘查深度要超过6 km;区内未来干热岩资源的开发应充分考虑深部热源条件、地表盖层厚度以及区域断裂对钻探工程的影响,这些认识对于本区未来干热岩资源勘查开发工作有一定的指导意义。The tectonically active southeastern coast of China is located in the subduction zone of the Eurasian Plate and the Philippine Sea Plate.At the same time,this area is also the main source of high radioactive granite in China.Development of large areas of Mesozoic acid granite bodies has resulted in abundant occurrence of hot dry rock.On the basis of regional geothermal and geological background,the Xiamen bay-Zhangzhou basin in the southeast coast of Fujian was selected for detailed investigations.The formation conditions of hot dry rock resources in this area are systematically analyzed from the perspective of regional geothermal flow,geothermal gradient,geothermal temperature,hot water circulation depth and deep temperature of geothermal reservoir.A suitable depth for exploration of the future hot dry rock resources in this area is scientifically calculated based on the data.The results show that(i)the average geothermal gradient in the area is about 18.3℃/km,lower than the average value for the continental areas;and(ii)the radioactive heat generation rate of the granite is only slightly higher than the global average value of the granite.The relatively high value of surface heat flow in the area is mainly due to mantle heat conduction,and the contribution of radioactive elements to heat generation is relatively low.The future development of hot dry rock resources in the area should take full account of the influence of deep heat source conditions,the thickness of ground cover and regional faults on drilling engineering.These factors will provide a framework guiding future exploration and development of hot dry rock resources in this area.

关 键 词：热储温度 干热岩 赋存条件 适宜深度 厦门湾-漳州盆地 

分 类 号：P314[天文地球—固体地球物理学]