苏北盆地沙埝油田阜三段储层微观特征及其与驱油效率的关系  

Reservoir Microscopic Characteristics and Displacement Efficiency of E_1f_3 Reservoir in Shanian Oilfield,Subei Basin

作　　者：张创[1,2] 孙卫[1] 解伟 

机构地区：[1]西北大学地质学系,大陆动力学国家重点实验室,陕西西安710069 [2]陕西延长石油(集团)有限责任公司研究院,陕西西安710069

出　　处：《现代地质》2011年第1期70-77,共8页Geoscience

基　　金：国家科技支撑计划项目(2007BAB17B00)

摘　　要：在对沙埝油田阜三段储层微观特征进行研究的基础上,利用真实砂岩微观模型水驱油实验得到驱油效率,探讨了物性和孔隙结构特征对驱油效率的影响,解释实验中出现渗透率相近的样品驱油效率却相差较大的特殊现象,并对退汞效率作为驱油效率的准确性进行分析。结果表明,储层岩石碎屑颗粒粒度细、分选较差、填隙物含量高,且经历了较强的压实作用,是造成孔隙喉道细小、非均质性较强的主要原因;驱油效率随物性变好、喉道变大而提高,但其与喉道分选性的关系较为复杂,大喉道一方面加剧了喉道间的非均质性,另一方面则提供了孔隙间良好的连通通道,分选较好的小喉道则保证了注入水的均匀推进;驱油效率主要受物性与最大连通喉道控制;真实砂岩微观模型水驱油实验所得的驱油效率与压汞实验所得的退汞效率相关性较好,但在低值区存在一定差异。On the basis of microscopic characteristics research of E1f3 reservoir in Shanian oilfield,oil displacement efficiency has been measured by the authentic sandstone micro-model experiment.Influences of physical properties and pore structure on oil displacement efficiency have been studied,and the special phenomenon of samples which have similar permeability but great different oil displacement efficiencies has been explained.Furthermore,the accuracy of mercury-withdrawal efficiency which is used as oil displacement efficiency has been analysised.The result shows that the rock of the reservoir is fine pore-throat and strong anisotropy,which mainly is due to the fine grain-size,poor sorting,high-content interstitial matter and high compaction.Oil displacement efficiency increases as the physical properties become better and the throats become larger,but it has a complex relationship with throat-sorting： large throat intensifies the heterogeneity between throats while it provides good connective channels among pores,and small throat ensures the uniform propulsion of the injection water.Oil displacement efficiency is mainly controlled by physical properties and the max connective throat,and it has a good correlation with mercury-withdrawal efficiency while they are different in the low-value zone.

关 键 词：孔隙结构 驱油效率 非均质性 低渗储层 沙埝油田 苏北盆地 

分 类 号：TE135[石油与天然气工程—油气勘探]