主成分分析法确定海上油田水驱效果评价关键指标

Application of principal component analysis on determining the key evaluation indicators of water flooding effects in offshore oilfield

目前海上油田水驱开发效果评价未形成一套完整、成熟的评价体系及行业标准,针对海上油田开发特征有必要建立一套可操作性强的水驱效果评价关键指标集。为此,分析了海上油田和陆上油田水驱开发的差异性和相似性,构建了以产量、采油速度为核心的海上油田注水开发效果评价常用指标集,并根据评价指标的独立性、动态性和可操作性进行了初选。最后基于典型海上水驱油田25个样本,应用主成分分析法,将各评价指标对水驱开发效果的重要程度进行排序,从储量动用、能量水平、产量变化、水驱状况及水驱效果5个方面最终确定10个关键指标,即水驱储量控制程度、水驱储量动用程度、压力保持水平、累积注采比、年注采比、年产油量自然递减率、剩余可采储量采油速度、含水上升率、水驱指数和采出程度。这些指标为科学评价海上油田的水驱效果提供了有利依据。

Water flooding effect evaluation in offshore oilfield has not formed a complete and mature evaluation system andindustry standards currently. It is necessary to establish a set of flexible water flooding evaluation system based on the char-acteristics of offshore oilfield development. Differences and similarities of the water flooding characteristics of the offshoreand onshore oilfields were analyzed. A set of commonly used water flooding evaluation indicator system was established fo-cusing on oil production and production rate. Evaluation indicators were primarily selected based on the principle of inde-pendence,dynamic and operability. According to 25 samples from the typical offshore water flooding reservoir,importanceof these indexes in water flooding evaluation was ranked using method of principal component analysis. Finally,10 key indi-cators were screened in aspects of recovery,energy,production,water flooding condition and water flooding effect,whichprovide favorable guidance for scientific evaluation of the water flooding effect in offshore oilfield. The indictors includecontrol degree and produced degree of the water flooding reserves,pressure support level,cumulative injection-productionratio,yearly injection-production ratio,natural decline rate of yearly oil production,oil production rate of remaining recov-erable reserves,raising rate of water cut,water flooding index and recovery degree of reserves.