鄂尔多斯盆地南部下寺湾探区致密油形成条件及富集模式  

Formation Conditions and Enrichment Pattern of Tight Oil in Xiasiwan Prospect,Southern Ordos Basin,China

作　　者：张凤博 胡慧 杨连如 李锦峰 鲁金凤 ZHANG Fengbo;HU Hui;YANG Lianru;LI Jinfeng;LU Jinfeng(Xiasiwan Oil Production Plant,Yanchang Oilfield Co.Ltd,Yan′an 716000,China;Xi′an Shiyou University,Xi′an 710065,China)

机构地区：[1]延长油田股份有限公司下寺湾采油厂,陕西延安716000 [2]西安石油大学地球科学与工程学院,陕西西安710065

出　　处：《河北地质大学学报》2025年第1期25-35,共11页Journal of Hebei Geo University

基　　金：国家科技重大专项(2017ZX05039001)。

摘　　要：鄂尔多斯盆地南部下寺湾探区致密油的研究尚属起步阶段。为此,以大量岩心实物、化验分析数据为基础开展研究。研究表明,长7致密油原油性质较好,烃源岩有机质丰度高,有机质类型主要为Ⅰ型和Ⅱ_(1)型,其次为Ⅱ_(2)型,有机质主体处于成熟-高成熟阶段,可得出长7油页岩总体评价为好烃源岩。储集层中的孔隙和裂缝形成了油气运移和排烃的有利通道。长7段发育稳定且连续的超压体,为油气的运移提供了充足且稳定的动力。根据生储盖的空间配置关系、已发现油气的分布特征及富集主控因素,可以将研究区油气富集模式划分为4种模式,即“薄砂质夹层成指状与烃源岩接触”模式、“倒灌富集”模式、“三明治式富集”模式与“就地滞留聚集”模式。The study of tight oil in Xiasiwan Prospect in the south of Ordos Basin is still in the initial stage.For this reason,the study was carried out based on a large number of physical cores and assay analysis data.The study shows that the crude oil properties of Chang7 tight oil are good,the organic matter abundance of hydrocarbon source rock is high,the organic matter type is mainly typeⅠandⅡ_(1),followed byⅡ_(2),and the organic matter body is in the stage of maturity-high maturity,so it can be concluded that the overall evaluation of Chang7 oil shale is a good hydrocarbon source rock.The pores and cracks in the reservoir form favorable channels for oil and gas transportation and hydrocarbon drainage.The development of stable and continuous overpressure body in the Long 7 section provides sufficient and stable power for oil and gas transportation.According to the spatial configuration of the reservoir cover,the distribution characteristics of the discovered hydrocarbons and the main controlling factors of the enrichment,the oil and gas enrichment mode in the study area can be divided into four modes,i.e.the mode of"thin sandy sandwiches in contact with the hydrocarbon source rock in the form of a finger",the mode of"inverted enrichment",the mode of"sandwich enrichment",and"in-situ retention and aggregation".

关 键 词：鄂尔多斯盆地 下寺湾探区 致密油 形成条件 富集模式 

分 类 号：P618.13[天文地球—矿床学]