优势流场发育阶段定量确定方法研究

长期注水开发过程中，由于储层物性差异、水油流度差异、注采差异、注入水长期冲刷及剥蚀等因素影响，油层内逐渐形成优势流场。矿场生产证明，优势流场对流体的分布和运移起重要作用，对剩余油的形成和分布有较强影响。但是实践也证明，不同开发区块、不同油藏类型、不同井网类型以及不同工作制度等条件下形成的优势流场有很大差异。依据优势流场中流场强度大这一主要特征，引入流场强度指数作为定量的界定指标，并与PV 数指数、采出程度及注水效率等参数结合，定量界定了优势通道的形成及所处阶段。当流场强度指数大于1.5，注水效率高，采出程度低时说明这是优势流场的初期阶段；流场强度指数大于1.5，注水效率低，采出程度低时说明是狭窄的优势通道，为优势流场的中期阶段；流场强度指数大于1.5，注水效率低，采出程度高时说明是优势流场的后期阶段，即已成为优势通道。

Research on the Quantitative Determination of the Dominant Flow FieldDevelopment Stages

Because of water/oil mobility ratio，injection/production difference，long term erosion and denudation，dominantflow field will gradually develop in reservoirs in the long process of waterflooding. It has been proved that distribution andmigration of liquid and formation of remaining oil are all greatly influenced by dominant flow field. It has also been proved thatthe dominant flow fields are quite different if formed in different blocks，different style reservoirs，different well patterns anddifferent working systems. According to the main feature of dominant flow field big streamline field intensity，streamline fieldindex（SFI）is induced to divide dominent flow field. The formation and stage of dominant flow field are divided by streamlinefield index and PV index，degree of reserve recovery and injection efficiency. The dominant flow field is at early stage whenstreamline field index is more than 1.5，and injection efficiency is high，and degree of reserve recovery is low. The dominantflow field is at middle stage when streamline field index is more than 1.5，and injection efficiency is low，and degree of reserverecovery is low. The dominant flow field is at later stage when streamline field index is more than 1.5，and injection efficiencyis high，and degree of reserve recovery is high.