应用分层技术重新认识濮城油田沙二上油藏

New knowledge of Upper Es_2 reservoir with layering technique in Pucheng Area

濮城油田西区沙二上2+3油藏为大厚层、严重非均质块状油藏,经过多年的注水开发,使储层孔隙结构改变,注采失调,油藏层间和层内矛盾突出,已进入特高含水开发后期,表现为高渗透层采出程度高、含水高,二、三类层动用程度低、剩余可采储量较大。因此,在油藏精细描述和剩余油研究的基础上,结合地质开发方案,开展了应用分层技术测试XP2-89、濮2-283、濮2-138井3口井的小层启动压力,通过测试成果量化认识层间非均质性,确认潜力层。通过将测试成果应用于区块改造、井网重组细分、认识剩余油分布,以及濮城南区沙二上2+3油藏的分注分采治理,油藏地层压力回升,动液面和生产压差相对稳定,地层能量保持与利用状况得到改善,达到了控水增油的目的。该技术对高含水油藏后期注水开发进行了有益的探索,是重新识别油藏的又一工艺思路,具有一定的推广应用价值。

Upper Es2^2＋3 reservoir is a thick massive oil pool with serious heterogeneity. The pore structure of reservoir has been changed after the flood development for many years, which leads to the imbalance of injection and production and serious interlayer contradictions. The reservoir has entered into the late development stage with extra-high water cut, showing a high degree of reserves recovery, high water cut, low producing degree of second-class and third-class reservoirs and more remaining recoverable reserves in high permeability reservoir. Therefore, based on the fine reservoir characterization and remaining oil study, the kickoff pressure of the sublayers of Wells XP2-89, P2-283, P2-138 are tested with the layering technique by combining with geological development plan. The interlayer nonuniformity is quantitatively recognized according to the testing result, identifying the potential reservoirs. The testing results have been applied for the block stimulation, well pattern reconstruction, knowledge of remaining oil distribution and controlling of Upper Es2^2＋3 reservoir for individual injection and individual production in the southern part of Pucheng Area, which make the formation pressure of reservoir build up, dynamic liquid level and drawdown pressure stable and the keeping and utilizing situations of producing energy improved. The destination of water controlling and oil increment has been attained. A beneficial probe has been studied by the technique to improve the recognition of late development stage of high water cut reservoir. The technique is a new thinking for the new knowledge of reservoir and has certain application value.