近岸水下扇多级次储层构型特征及剩余油分布——以Bongor盆地X油田下白垩统油层为例  

Multilevel architectural characteristics of reservoirs and remaining oil distribution of nearshore subaqueous fan:taking the Lower Cretaceous oil layer of X Oilfield in Bongor Basin as an example

作　　者：冯烁 刘倩 彭子霄 付超[1] 李苏磊 刘明慷 FENG Shuo;LIU Qian;PENG Zixiao;FU Chao;LI Sulei;LIU Mingkang(School of Energy,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：《东北石油大学学报》2022年第2期58-71,I0004,I0005,共16页Journal of Northeast Petroleum University

基　　金：国家自然科学基金项目(42172112);国家科技重大专项(2017ZX05001-002-003)。

摘　　要：陆相断陷湖盆近岸水下扇沉积体内部厚层砂体结构复杂,剩余油分布规律认识不清。以Bongor盆地X油田下白垩统油层为例,根据岩心观察、密井网测录井、生产动态等资料,分析研究区下白垩统典型厚层近岸水下扇沉积序列,研究不同级次下的储层构型及其对沉积体内剩余油分布的控制作用。结果表明:研究区可识别泥质沉积面、冲刷/侵蚀面两类界面,近岸水下扇构型单元划分为7个级次(一级~七级),识别分支水道、席状砂、分支水道间和末端水道4种四级构型单元,复合分支水道为五级构型单元。储层内剩余油分布受四级、五级构型单元平面展布特征控制,具有构型界面夹层垂向控油和分支水道砂体横向控油两类模式,构型单元平面连通性及界面阻隔是控制油水连通的主要因素。该结果为近岸水下扇砂砾岩储层开采后期剩余油挖潜提供指导。The sedimentary body of nearshore subaqueous fan developed in continental faulted lake basin has complex structure of thick sand body,and the distribution law of remaining oil is not clear.According to the data of core observation,dense well pattern logging and production performance,the sedimentary sequence of typical thick layer nearshore subaqueous fan of Lower Cretaceous in X Oilfield of Bongor Basin is studied,and the reservoir architecture at different levels and its control effect on the distribution of remaining oil in the sedimentary body are analyzed.The results show that the study area can identify two types of interfaces:sedimentary discontinuity and channel scouring/erosion surface.The architecture unit of nearshore subaqueous fan is divided into seven levels(level 1 to level 7).On the basis of lithofacies division,four types of four level configuration units are identified:distributary channel,inter channel,sheet sand and end channel,and the composite distributary channel is five level architecture unit.The plane distribution characteristics of four-level and five-level architecture units are quantified,and two models of architectural interface interlayer vertical oil control and distributary channel sand body horizontal oil control are proposed.The plane connectivity and interface barrier of architecture units are the main factors controlling oil-water connectivity.The results provide reference and guidance for remaining oil displacement in the later stage of oilfield production.

关 键 词：近岸水下扇 储层构型 构型界面 剩余油分布 下白垩统 X油田 Bongor盆地 

分 类 号：TE112.21[石油与天然气工程—油气勘探]