高含水油田密闭取心检查井水淹状况及主控因素研究:以扶余油田泉四段油层为例

Waterflooded situation and its key controlling factors in sealed coring of inspection wells at high water-cut stage:A case study of Quan-4 Formation of Fuyu Oilfield

密闭取心是高含水油田认识剩余油分布的重要手段。文章以扶余油田泉四段高含水期密闭取心井资料为例,系统提出了判别密闭取心井水淹状况的定性、定量结合的分析方法,定性方法包括岩心肉眼观察、镜下观察以及滴水试验等,定量方法包括岩心密闭情况判别、岩心分析油水饱和度校正、原始含饱和度计算、驱油效率及其与产水率关系确定以及水淹程度的分类及判别标准。应用上述方法实际分析了5口近期密闭取心检查井资料,统计了单井及总体的水淹特征,并结合密闭取心井层内、层间、平面非均质性以及所在位置的注采井位关系,提出了水淹状况及剩余油分布的主控因素,为进一步挖掘剩余油潜力奠定了基础。

Sealed coring is an important means of understanding the remaining oil distribution in high water-cut oil field.Based on the sealed coring data of Quan-4 Formation of Fuyu Oilfield at high water cut stage,this paper systematically demonstrates the qualitative and quantitative method to determine the water flooded situation of sealed coring well.The qualitative methods include：（1） observation with naked eyes;（2） microscope observation;（3） dripping test.The quantitative methods include：（1） determination of sealing condition of cores;（2） correction of oil and water saturation from core analysis;（3） calculation of original oil saturation;（4） determination of oil displacement efficiency of cores and its relationship with water production rate;（5） classification and discrimination criteria of water flooded extent.With this method,we analyzed 5 recent sealed coring wells and counted the waterflooded features of single well and all wells.Combined with the intralayer,interlayer and planar heterogeneity and the position relationship of the injection and production wells near the location of the sealed coring wells,key controlling factors of remaining oil distribution and water flooded condition were proposed,which play a fundamental role in the further mining of remaining oil.