基于正演模拟的复合曲流带砂体内部构型解剖研究及应用  

Sandbody architecture of complex meander belt deposition based on forward modeling and its application in offshore oilfield

作　　者：何康 胡勇 甘立琴 来又春 苏进昌 HE Kang;HU Yong;GAN Linqin;LAI Youchun;SU Jinchang(Bohai Oilfield Research Institute,CNOOC China Limited,Tianjin Branch,Tanggu300459,Tianjin,China)

机构地区：[1]中海石油(中国)有限公司天津分公司渤海石油研究院,天津塘沽300459

出　　处：《地质找矿论丛》2019年第1期84-91,共8页Contributions to Geology and Mineral Resources Research

基　　金：国家科技重大专项"海上油田从式井网整体加密及综合调整技术(编号:2011ZX05024-002-007)"资助

摘　　要：Q油田是渤海大型河流相沉积的稠油油田,其北区NmⅣ1主力含油砂体为复合曲流带沉积,经过16年的注水开发,油水关系复杂,平面注水受效不均的问题日益严重,如何优化注釆结构来改善开发效果已成为急需解决的问题。优化现有注釆井网的关键是认识复合曲流带砂体内部不同单河道砂体的切叠关系及展布特征,即对目标砂体开展内部不同单河道的构型单元分布特征研究。首先,依据岩电标定的测井曲线特征、局部发育的薄夹层以及曲流河纵向下切模式,对复合砂体内部不同单河道砂进行划分与对比;然后基于单井沉积微相划分结果,开展井间剖面相对比分析,表明复合砂体内部存在5种不同单河道砂体切叠模式;建立5种正演概念模型,利用地震正演模拟合成地震记录,总结了不同单河道砂体间顶面高程差异、点坝边界、废弃河道等曲流河砂体构型边界的波形特征;利用地震属性提取及多种地质构型方法,综合分析,最终实现了海上大井距条件下复合曲流带砂体内部不同单一曲流河砂体构型边界的精细识别;最后由注采动态资料的响应关系评估不同的切叠模式对注水效果的侧向遮挡程度,并以此为依据,优化现有的注釆井网并取得了非常好的生产效果。Q oil field is a big fluvial deposition heavy oil field in Bohai.The NmⅣ1 oil-bearing sand body is composed of abandoned meander belt sedimentation.After more than 15 years’waterflood development,the present situation of the complex oil-water distribution and ineffective water-injection is grim.How to optimize the injection structure and improve the development more effectively is a main problem that the oilfield is facing.The key to optimizing the existing well network is identifying different single meander river sands and distinguishing the connection line between different sand bodies within or beyond separate channels.First of all,according to the characteristics of rock-electic logging curve,thin layers and the incision of channel,the different single channel sandbodies can be identified within the complex meander belt deposition in the process of multiple wells section correlation.Second,based on recognition of sedimentary microfacies,five different micro phase sand body cutting relations within or beyond single channel in meander belt were concluded by wells correlation.Five respective geological models were built based on five connections described above.Through combined seismic record obtained from seismic forward modelling,the different seismic wave features of the structure boundary of meander river sand body are summarized such as height difference between sand bodies,point bar boundary and abandoned channel etc.By the method of seismic attribute extraction and various geologic configuration,precise recognition of different single river sands within complex meander belt deposition will be realized.At last,accompanied with production dynamic data,the degree of lateral barrier of water injection effect is evaluated by different cutting modes.According to that,there is a very good effect by optimizing the injection structure.

关 键 词：复合曲流带 单河道 正演模拟 构型边界 注釆结构优化 渤海油田 

分 类 号：TE53[石油与天然气工程—油气田开发工程]