陆相碳酸盐质细粒沉积岩及油气甜点多源成因  

Multi-source genesis of continental carbonate-rich fine-grained sedimentary rocks and hydrocarbon sweet spots

作　　者：姜在兴[1] 孔祥鑫[1] 杨叶芃[1] 张建国[1] 张元福[1] 王力 袁晓冬 JIANG Zaixing;KONG Xiangxin;YANG Yepeng;ZHANG Jianguo;ZHANG Yuanfu;WANG Li;YUAN Xiaodong(School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国地质大学(北京)能源学院,北京100083

出　　处：《石油勘探与开发》2021年第1期26-37,共12页Petroleum Exploration and Development

基　　金：国家科技重大专项“大型油气田及煤层气开发”(2017ZX05009-002);国家自然科学基金面上项目(41772090);中国博士后科学基金(2020M680624)。

摘　　要：基于以往研究认识,通过分析细粒碳酸盐物质来源和岩石形成作用,系统论述碳酸盐质细粒沉积岩的多源成因机制,并对碳酸盐质细粒沉积岩的油气富集类型进行总结。研究表明,以陆地物质输入、盆内自生物质生成、火山热液物质注入和混合物质来源为主的多物源供给是陆相断陷盆地富集细粒碳酸盐物质的主要原因。其中物源区富碳酸盐岩基岩的发育控制了盆内碳酸盐物质充填的规模,火山热液活动可向湖盆提供碱性流体以增加碳酸盐晶体形成的物质供给量,受生物活动诱导形成的自生碳酸盐晶体是湖盆内细粒碳酸盐物质长期积累的主要来源。在沉积及沉积后阶段,受物理、生物化学和化学作用的相互影响,形成了具有多种特征的碳酸盐质细粒沉积岩。物质来源与沉积成因对陆相碳酸盐质细粒沉积岩内的油气富集具有控制作用。在多源成因体系中,油气富集甜点类型可包含内源型、陆源型、火山热液型和混源型等。This paper systematically discusses the multiple source characteristics and formation mechanisms of carbonate-rich fine-grained sedimentary rocks through the analysis of material source and rock formation.The hydrocarbon accumulation characteristics of carbonate-rich fine-grained sedimentary rocks are also summarized.The results show that the main reason for the enrichment of fine-grained carbonate materials in rift lake basins was the supply of multiple material sources,including terrestrial material input,formation of intrabasinal authigenic carbonate,volcanic-hydrothermal material feeding and mixed source.The development of carbonate bedrock in the provenance area controlled the filling scale of carbonate materials in rift lake basins.The volcanic-hydrothermal activity might provide an alkaline fluid to the lake basins to strengthen the material supply for the formation of carbonate crystals.Authigenic carbonate crystals induced by biological processes were the main source of long-term accumulation of fine-grained carbonate materials in the lake basins.Carbonate-rich fine-grained sedimentary rocks with multiple features were formed through the interaction of physical,biochemical and chemical processes during the deposition and post-deposition stages.The source and sedimentary origin of the fine-grained carbonate rock controlled the hydrocarbon accumulation in it.In the multi-source system,the types of“sweet spots”of continental shale oil and gas include endogenous type,terrigenous type,volcanic-hydrothermal type and mixed source type.

关 键 词：碳酸盐质细粒沉积岩 断陷湖盆 多元物源 油气富集 陆相页岩油气甜点 

分 类 号：TE631.4[石油与天然气工程—油气加工工程]