克拉玛依油田特低渗透下乌尔禾组储层渗流机理研究.docVIP

克拉玛依油田特低渗透下乌尔禾组储层渗流机理研究 　　摘要: 新疆克拉玛依油田下乌尔禾组储层是一个低孔、特低渗透、微裂缝发育的厚层状砾岩油藏,根据储层物性特征和渗流能力评价,反映了储层低孔低渗的特征。通过对比新疆克拉玛依、大庆、长庆同等渗透率级别岩心对比,表明新疆克拉玛依油田下乌尔禾组特低渗储层岩心喉道分布曲线的峰值最低,大级别喉道含量最高,大喉道的存在为有效渗流能力提供了良好的通道,同时又受到小吼道的限制作用;可动流体饱和度分布较宽,相对较大;启动压力梯度和储层渗透率大小关系密切,储层渗透率越低,启动压力梯度越大,说明了其开发难度大的原因。依据这三个参数对低渗透储层进行分类和评价,新疆克拉玛依油田下乌尔禾组储层特低渗储层以三类储层为主,部分二类下限储层,表明有一定的开发潜力,但开发难度较大。 　　Abstract: Lower Wuerhe reservoir of District No.8 in Karamay oil field is a thick massive ultra reservoir with low permeability and well developed micro-fracture conglomerate reservoir, based on the evaluate of physical property feature and filtration capability, it reflects the feature of low-porosity and low-permerbility of the reservoir. Compared with the Karamay, Da-qing and Chang-qing drilling core, it demonstrates that the drilling cores of lower Wuerhe reservoir have the lowest peak value of throat distribution curve, the content of big throat is the highest, the existence of big throat provides favorable passageway for effective filtrate, and is restricted by the small throat; the saturation of movable fluid distributes broadly; the start-up pressure gradient was closely communicated with the dimension of permeability, this indicates the difficulty of development. The Lower Wu’erhe Reservoir is mainly on Ⅲ reservoir, and partly Ⅱ reservoirin the light of the classification and evaluation of the three parameter, and it demonstrates that it has definite develop potential, but it is relative difficult to develop. 　　关键词: 特低渗透;同类对比;分类评价;开发难度大 　　Key words: extremely low permeability;allied comparison;classified evaluation;difficult to develop 　　中图分类号:TE3文献标识码:A文章编号:1006-4311(2010)25-0142-02 　　 　　0引言 　　新疆克拉玛依油田下乌尔禾组储层具有埋藏深、巨厚、低孔、特低渗特点的砾岩油藏,加密调整后多数油井见效差,采油速度及最终采收率低,油藏有效厚度大、储量丰度高的潜力远得不到发挥。油藏开发难度大,为了进一步深入研究克拉玛依油田下乌尔禾组储层(八区、530井区)的物性特征及渗流能力,以了解产量递减,及注水有效性等问题,充分认识储层特征及其开发潜力,进行分析储层渗流机理研究。 　　1储层物性特征及渗流能力评价 　　根据新疆克拉玛依油田下乌尔禾组储层岩心分析化验结果,储层渗透率主要分布于0.6×10-3μm2以下,孔隙度分布于8%~16%之间,属于低孔、特低渗储层。孔隙度与渗透率总体上存在一定的正相关性,部分岩心孔、渗呈现负相关关