湖南保靖志留系龙马溪组页岩气储集空间精细表征  

Fine description of shale gas reservoir space of Silurian Longmaxi Formation in Baojing,Hunan Province

作　　者：李斌 胡博文 任玺宁 罗群[3] 董振国 刘国辉 Li Bin;Hu Bowen;Ren Xining;Luo Qun;Dong Zhenguo;Liu Guohui(Hanshan Normal University,Chaozhou,Guangdong 521041;Shenhua Geological Co.,Ltd.,Beijing 102249;China University of Petroleum(Beijing),Beijing 100049)

机构地区：[1]韩山师范学院,广东潮州521041 [2]神华地质勘查有限责任公司,北京102249 [3]中国石油大学(北京),北京100049

出　　处：《地质科学》2024年第6期1639-1661,共23页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家“973”项目“陆相致密油甜点成因机制及精细表征”(编号:2015CB250901);韩山师范学院2021年教授(博士)启动项目“湖南保靖地区志留系龙马溪组页岩气储层精细描述与页岩气富集成藏机理”(编号:QD202107)资助。

摘　　要：湖南保靖页岩气勘探中发现页岩气储层纵向变化较大,页岩气显示不稳定,需要储层地质学深入研究。使用氩离子抛光扫描电镜、X射线衍射全岩分析等技术对湖南保靖地区下志留统龙马溪组页岩气储层进行详细描述。研究结果表明:湖南保靖页岩气储集空间主要包括有机质孔、无机质孔和微裂缝3种类型。优质的页岩气储集空间为有机质孔、无机质孔中的溶蚀孔和微裂缝。将页岩储集空间孔—缝配置关系划分出构造贯通型、构造边缘型、边缘环闭型、挤压破碎网络型、充填封堵型、分散独立型6种类型,其中构造贯通型、边缘环闭型、挤压破碎网络型为优质孔缝配置关系,有利于页岩气成藏富集。页岩气含气性测试证明,页岩气含气量与TOC、渗透率、微裂缝发育程度呈正相关关系,黑色碳质泥岩相、黑色碳质粉砂岩相、黑色含碳泥岩相中贯穿有机质孔、溶蚀孔的微裂缝网络结构系统是页岩气聚集的主要储集空间,是下一步勘探的重要目标。In the exploration of shale gas in the Baojing area of Hunan Province,it was found that the vertical variation of shale gas reservoirs was significant,and the shale gas display was unstable,requiring in-depth research on reservoir geology.The shale gas reservoir of the Longmaxi Formation of the Lower Silurian in Baojing area,Hunan Province,was described in detail by using argon ion polishing scanning electron microscopy and X-ray diffraction whole-rock analysis.The research results showed that the reservoir space of Baojing shale gas in Hunan Province mainly included 3 types:organic matter hole,inorganic matter pores,and microcracks.The reservoir space of high-quality shale gas was organic matter pore,dissolution pore in inorganic pores and microfracture.The pore-fracture configuration relationship in shale reservoir space could be divided into 6 types:structural through type,structural edge type,edge ring type,compression fracture network type,filling and plugging type,and distributed independent type.Among them,structural through type,edge ring type,compression fracture network type were high-quality pore-fracture configuration relationships,which was conducive to shale gas accumulation and enrichment.The gas content test of shale gas showed that the gas content of shale gas was positively correlated with the mesopore and microfracture,so the microfracture network structure system that ran through the organic matter pore throat and dissolution pore in the black carbonaceous mudstone facies,black carbonaceous siltstone facies,and black carbonaceous mudstone facies were the main storage space for shale gas accumulation,which was the important target for the next exploration.

关 键 词：储层 扫描电镜 龙马溪组 页岩气 湖南保靖 

分 类 号：P618.13[天文地球—矿床学]