裂缝性潜山油藏渗流特征及不稳定注水策略——以渤海锦州25-1南油田潜山油藏为例  

Percolation characteristics and unstable water injection strategy of fractured buried hill reservoirs:Taking the buried hill reservoir in Bohai JZ25-1S oilfield as an example

作　　者：苏彦春 朱志强 SU Yanchun;ZHU Zhiqiang(CNOOC China Limited,Tianjin Branch,Tianjin 300459,China)

机构地区：[1]中海石油(中国)有限公司天津分公司

出　　处：《中国海上油气》2019年第6期78-85,共8页China Offshore Oil and Gas

基　　金：“十三五”国家科技重大专项“渤海油田加密调整及提高采收率油藏工程技术示范（编号：2016ZX05058-001）”部分研究成果

摘　　要：裂缝性潜山油藏渗流特征复杂,实际开发过程中油井水窜严重,并且有效控水难度大。以渤海锦州25-1南油田潜山油藏为对象,开展了不同裂缝倾角岩心的应力敏感实验和基质岩心渗吸实验,准确获取了影响该类油藏渗流特征的2个关键参数,即裂缝的应力敏感程度和基质的渗吸程度;在此基础上利用Eclipse软件建立了双重介质油藏数值模型,通过示踪剂追踪技术定量刻画出裂缝性油藏的渗流特征。结果表明基质和裂缝渗流特征差异大,裂缝以初期供油为主,基质则是后期产量接替的关键;根据基质渗吸特征将其渗流进一步划分为蛰伏、发轫、旺汲渗和平息等4个阶段。在此基础上,结合相似油田开发经验,构建了裂缝性潜山油藏不稳定注水策略,即初期降压开采、低含水阶段脉冲注水、中含水阶段周期注水和高含水阶段异步注采等,并在锦州25-1南油田潜山油藏开展了矿场试验,控水稳油效果显著,可为类似油藏注水开发提供借鉴。The percolation characteristics of fractured buried hill reservoirs are complex.During the actual development of those reservoirs,oil wells are subjected to serious water channeling,and the difficulty in effective water control is huge.Taking the buried hill reservoir of JZ25-1S oilfield as the object,the stress sensitivity experiment and matrix core infiltration experiment of were carried out cores with different fracture dips,and two key parameters affecting the percolation characteristics of reservoir were obtained accurately,that is,the stress sensitivity of fracture and the infiltration degree of matrix.On this basis,the Eclipse software was used to establish a dual-media reservoir numerical model,and the percolation characteristics of fractured reservoirs were quantitatively characterized by tracer tracking technology.The results show that the percolation characteristics of matrix and fracture are obviously different,the fracture mainly supplies oil at the initial stage,and the matrix is the key to the subsequent production succession.According to the characteristics of matrix infiltration,the percolation can be further divided into four stages:dormancy,start-up,peak infiltration and ceasing.On this basis,combined with the development experiences of similar oilfields,the unstable water injection strategy of fractured buried hill reservoir has been made,namely,the initial pressure drop production,pulse water injection in low water cut stage,periodic water injection in middle water cut stage and asynchronous injection-production in high water cut stage.The field test was carried out in the buried hill reservoir of JZ25-1S oilfield,and significant effect of controlling water and stabilizing oil was achieved,which could provide references for water injection development of similar reservoirs.

关 键 词：裂缝性潜山油藏 应力敏感 基质渗吸 渗流特征 不稳定注水策略 锦州25-1南油田 

分 类 号：TE344[石油与天然气工程—油气田开发工程]