三角洲前缘有利沉积相带储层非均质性及成因认识  

Understanding of reservoir heterogeneity and genesis of favorable sedimentary facies belt at delta front

作　　者：吴磊磊[1] 刘洪军 张小东[1] 张鹏[3] 李秀[1] WU Leilei;LIU Hongjun;ZHANG Xiaodong;ZHANG Peng;LI Xiu(Jingbian Oilfield,Yanchang Petroleum Co.Ltd.,Jingbian 718500,China;School of Earth Sciences and Engineering,Xi’an Shiyou University,Xi’an 710065,China;Huabei Division,China Petroleum Logging Co.Ltd.,Renqiu 062550,China)

机构地区：[1]延长油田股份有限公司靖边采油厂,陕西靖边718500 [2]西安石油大学地球科学与工程学院,陕西西安710065 [3]中国石油测井有限公司华北分公司,河北任丘062550

出　　处：《复杂油气藏》2023年第3期248-255,共8页Complex Hydrocarbon Reservoirs

基　　金：延长油田股份有限公司科技攻关项目“延长油田西部致密油成藏控制因素及富集规律研究”(YT1115SFW0069);陕西省教育厅重点科学研究计划项目“湖盆深水砂岩中泥/钙质隔夹层对致密油成藏控制机理研究-以鄂尔多斯盆地长6段为例”(20JS126)。

摘　　要：储层非均质性是影响油气分布和后期挖掘剩余油的重要因素之一。综合利用测录井、岩心等资料,分析靖边油田新城区三角洲前缘有利沉积相带储层非均质变化规律及其影响因素。结果表明:长6段储层非均质主要表现为单砂体非均质和砂体结构非均质。单砂体非均质主要有正韵律和反韵律非均质,对应于水下分流河道和河口坝沉积微相;砂体结构非均质分为块状叠合箱型、叠合箱型、叠合椭圆型、叠合漏斗型等四种类型。砂体结构影响着油水分布,油藏主体以复合叠置砂体结构为主,边部为孤立性砂体,纵向上块状叠合箱型和叠合椭圆型含油性最好。储层非均质性的主要影响因素为沉积微相、成岩作用、基准面升降和构造作用。沉积作用导致砂体叠置样式和碎屑颗粒差异形成了复合砂体内部非均质性;成岩作用是引起单砂体内部非均质的主要原因;构造裂缝主要起渗流通道作用,增强了局部导流能力,使储层非均质性更加复杂;基准面旋回影响砂体叠置样式,进而影响储层垂向非均质性。储层非均质性研究可为油田合理开发提供参考建议。Reservoir heterogeneity is one of the important factors affecting the distribution of oil and gas and the excavation of remaining oil in the late stage.By comprehensive use of well logging and core data,this paper analyzes the variation of reservoir heterogeneity and its influencing factors in the favorable sedimentary facies belt at the delta front in the Xincheng District of Jingbian Oilfield.The results show that the reservoir heterogeneity of Chang 6 member is mainly characterized by single sand-body heterogeneity and heterogeneity of sand-body structure.The single sand-body heterogeneity mainly includes positive rhythm and anti-rhythm heterogeneity,corresponding to the sedimentary microfacies of underwater distributary channels and estuarine dams.The structural heterogeneity of the sand-body can be divided into four types:massive superimposed box,superimposed box,superimposed oval,and superimposed funnel.The structure of the sand-body affects the distribution of oil and water.The main body of the reservoir is dominated by the composite superimposed sand body,with the isolated sand body at the edge.The block superimposed box type and superimposed oval type are the best oil content in the longitudinal direction.The main influencing factors of reservoir heterogeneity are sedimentary microfacies,diagenesis,base-level rise and fall,and tectonism.The inhomogeneity of the composite sand-body is formed by the difference between the superimposed pattern and the clastic particles caused by sedimentation.Diagenesis is the main cause of the internal inhomogeneity of the single sand-body.Structural fractures mainly act as seepage channels,which enhance the local conductivity,and make the reservoir heterogeneity more complicated.The base level cycle affects the superposition pattern of sand bodies,which in turn affects the vertical heterogeneity of the reservoir.The study of reservoir heterogeneity can provide references for the reasonable development of oilfield.

关 键 词：三角洲前缘 储层非均质性 砂体结构 基准面旋回 靖边油田 

分 类 号：TE132[石油与天然气工程—油气勘探]