安塞油田黑山梁区长6油层组单砂体构型分析及平面展布特征  

Configuration analysis and plane distribution characteristics of single sand body in Chang 6 reservoir formation of Heishanliang area,Ansai oilfield

作　　者：马江波 冯纪慧 李刚[1] 韩彦斌[1] 张寰萌 郭岭[2] Ma Jiangbo;Feng Jihui;Li Gang;Han Yanbin;Zhang Huanmeng;Guo Ling(Xingzichuan Oil Production Plant of Yanchang Petroleum Co.,Ltd.,Yan'an,Shaanxi 717400;Department of Geology,Northwest University,Xi'an 710069)

机构地区：[1]延长石油股份有限公司杏子川采油厂,陕西延安717400 [2]西北大学地质学系,西安710069

出　　处：《地质科学》2024年第4期1018-1033,共16页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金项目(编号:42130206,41302076)资助。

摘　　要：安塞油田黑山梁区块位于延安市安塞区,三叠系延长组长6油层组是其主力产油层。目前该区已进入注水开发阶段,但砂体展布、非均质性、砂体叠置规律等认识不清,导致开发过程中存在注水受效程度不均衡,整体水驱效果差等问题。为此,本次研究依托丰富的测井、录井资料,以及岩心、镜下薄片资料和分析测试数据,开展地层精细刻画、沉积微相、砂体平面分布及单砂体叠置规律的综合研究。结果表明:黑山梁地区长6时期主要发育三角洲前缘亚相,岩性以细粒长石砂岩为主,分选性中等-好,磨圆度中等,水下分流河道和分流间湾微相较为多见,河口坝微相发育较少;水下分流河道为优势相,砂岩分布广、厚度大,沿河道方向延伸,早期形成的河口坝由于波浪作用和分流河道侵蚀作用被破坏,河口坝无法保存完整,仅有部分痕迹。砂体类型包括水下分流河道砂和河口坝砂两种,单砂体垂向叠置可分为孤立型、叠加型和切叠型3种;侧向拼接样式可分为孤立式、对接式和侧切式3种。研究区内砂体沿北东-南西方向呈长条状展布,由于河道频繁摆动和分叉,砂体切叠现象明显,顺物源方向砂体连通性较好,垂直物源方向砂体被分流间湾泥隔开,砂体连通性较差,并结合生产动态数据,认为砂体连通程度越高,水驱动用效果越好。基于该研究成果建立了研究区曲流河三角洲沉积模式,为后期油藏完善注采井网、分层注水开发方案调整提供地质依据。Heishanliang block of Ansai oilfield is located in Ansai area,Yanan City.The Triassic Yanchang Chang 6 oil formation is its main oil producing layer.At present,the area has entered the stage of water injection development,but there is a lack of clear understanding of the distribution,heterogeneity and stacking patterns of sand bodies,leading to problems such as imbalanced water injection efficiency and overall poor water drive effect during the development process.Therefore,this study relies on rich logging data,core data,microscopic thin section data,and analysis test data to conduct a comprehensive study on fine stratigraphic characterization,sedimentary microfacies,sand body plane distribution and single sand body stacking law.The results show that during the Chang 6 period,the delta front subfacies were mainly developed in the Heishanliang area,with fine-grained feldspathic sandstone as the main lithology,moderate to good sorting and roundness.Underwater distributary channels and inter distributary bay microfacies were more common,and the development of mouth bar microfacies was less;the underwater distributary channel is the dominant facies,and the sandstone is widely distributed and thick,extending along the river channel.The early formed estuary dam was damaged due to wave action and erosion of the distributary channel,and the estuary dam cannot be preserved completely,with only some traces.The types of sand bodies include underwater distributary channel sand and estuarine dam sand.The vertical stacking of single sand bodies can be divided into three types:isolated type,stacked type and shear stacked type;the lateral splicing styles can be divided into three types:isolated,docking and side cut.The sand bodies in the research area are distributed in a long strip shape along the northeast-southwest direction,due to frequent oscillation and bifurcation of the river channel,the sand bodies are significantly cut and stacked,and the connectivity of the sand bodies along the source direction is good.The sand bodi

关 键 词：曲流河三角洲 砂体构型 沉积模式 长6油层组 黑山梁区 安塞油田 

分 类 号：TE122.2[石油与天然气工程—油气勘探]