四川盆地水热型地热资源构造成因模式  

Structural genetic model of geothermal resources in Sichuan Basin

作　　者：李金玺 孙东 李智武[4] 曹楠[2,3] 童馗 廖俊[1] 张正鹏 董建兴[2] 章旭 Li Jinxi;Sun Dong;Li Zhiwu;Cao Nan;Tong Kui;Liao Jun;Zhang Zhengpeng;Dong Jianxing;Zhang Xu(Key Laboratory of Earth Exploration and Information Techniques of Ministry of Education,Chengdu University of Technology,Chengdu 610059;Sichuan Geological Environment Survey and Research Center,Chengdu 610081;Sichuan Huadi Construction Engineering Co.,Ltd.,Chengdu 610081;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059)

机构地区：[1]地球勘探与信息技术教育部重点实验室,成都理工大学,成都610059 [2]四川省地质环境调查研究中心,成都610081 [3]四川省华地建设工程有限责任公司,成都610081 [4]油气藏地质及开发工程国家重点实验室,成都理工大学,成都610059

出　　处：《地质科学》2023年第2期438-460,共23页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金项目(编号:41602153,41472107,41230313)资助。

摘　　要：地处青藏高原东缘的四川盆地是一个群山环绕的叠合型沉积盆地,蕴含着丰富的地热资源。四川盆地具有突变型和渐变型两类盆山结构,二者的构造样式存在明显差异,对盆地及周缘的水热型地热资源分布具有明显的控制作用。通过解析盆地及周缘地质构造,明确了盆地不同构造单元的构造样式;详细对比分析已有的地热勘查案例的异同性,提出了褶皱型、单斜型和褶皱—断裂复合型等3大类水热型地热资源的构造成因模式;认为四川盆地形成与演化过程中,构造运动与水热型地热资源的形成密切相关,主要表现在:1)频繁不均匀升降运动导致构造—沉积格局分异,控制着地热储盖层岩性、组合及区域展布;2)构造抬升形成的不整合面和古岩溶作用极大改善了地热储层的孔渗物性和流体输导能力,形成了优质的碳酸盐岩孔洞型热储;3)断裂可能是地下热水的补给通道和输导系统,亦或是阻隔屏障,取决于断裂类型和断层两盘岩性配置关系;4)地下热水易于沿具走滑分量断层和张性断层进行补给和输导。The Sichuan Basin located in the eastern margin of the Tibetan Plateau is a superimposed sedimentary basin surrounded by mountains and contains abundant geothermal resources.There are two types of basin-mountain structures in Sichuan Basin:abrupt change type and gradual change type.The tectonic styles of the two types are obviously different,which control the distribution of geothermal resources in the basin and its periphery.The tectonic styles of different tectonic units of the basin are analyzed.Detailed comparisons and analysis of the differences of geothermal exploration cases are used to find their formation mechanism.Three tectonic genesis models of geothermal resources are proposed:fold type,monocline type and fold-fault compound type.It is believed that tectonic movement is closely related to the formation of geothermal resources during the process of the formation and evolution of Sichuan Basin.Firstly,frequent uplift and descend lead to structural and sedimentary differentiation,which controls the lithology,assemblage and regional distribution of geothermal reservoir and cap rocks.Secondly,the unconformity caused by tectonic uplift and paleokarstification greatly improve the porosity and permeability of geothermal reservoirs and fluid transport capacity,and form high-quality carbonate reservoirs.Thirdly,the fault may be a recharge channel and transport system of geothermal water or a barrier,depending on the type of fault and the lithologic configuration of its both sides.Finally,groundwater is easy to recharge and transport along strike-slip and/or normal fault.

关 键 词：地质构造 构造样式 地热储层 地下热水 四川盆地 

分 类 号：P314[天文地球—固体地球物理学] P542[天文地球—地球物理学]