近废弃油藏再度开发含水下降原因分析

The reason analysis for decrease of water cut during developing the nearly abandoned reservoir again

基于流体势原理和油气运移成藏理论,运用动态分析、油藏数值模拟、物理模拟手段,以东辛油田辛1沙一段4砂组油藏为例分析了近废弃油藏再度开发含水下降的主要原因。研究认为,动用了未动用储量是补孔油井含水下降的根本原因,而重力分异作用下的剩余油再富集成藏是高含水关停油井获得再度开发、含水大幅下降的根本原因。研究结果表明,静置条件下的剩余油再富集成藏机理为水驱断块油藏开发后期的挖潜与提高采收率,尤其周期注采开发油藏的效益开发,停产与半停产油藏的产能恢复及废弃油藏的再度开发等指明了方向。

On the basis of the theory of fluid potential energy and petroleum migration and accumulation,using the way about production performance analysis,oil reservoir numerical simulation and physical simulation,the reason analysis for decrease of water cut was re-searched and analysed during developing the nearly abandoned reservoir again.The study in- dicates that remaining oil of enrichment again and undeveloped reserves should be the major reason.The research result has guide importance to tapping potential and enhancing oil re- covery at the late oil development stage of water driving oil reservoir.Especially,the mecha- nism very practically apply to developing cycle injection-production development reservoir, stop production or Semi-stop production reservoir, abandoned reservoir.