孤岛油田馆(1+2)砂层组沉积模式及其对剩余油分布的控制

在地层划分和对比的基础上,结合粒度分析、河流砂体形态、河流曲度等特征,对孤岛油田馆(1+2)砂层组沉积模式进行了研究。结果表明,馆(1+2)砂层组属河流相沉积,对比Miall的16种河流分类方案,其属于细粒曲流河沉积。剩余油分布研究表明,馆(1+2)油藏主力油层仍是剩余油分布富集区,非主力油层则是剩余油分布高饱和度区;受注水波及程度和重力分异作用的影响,储层内部垂向上形成中上部剩余油富集,而平面上低渗结构单元和注采不完善地区剩余油富集。孤岛油田馆(1+2)砂层组曲流河相沉积模式控制了储层砂体的内部结构和宏观非均质性以及注入水的空间运动规律,从而控制了剩余油的空间分布。

Sedimentary model of Guan (1 + 2) sand sets and its control over distribution of remaining oil in Gudao Oilfield

Combined with granularity analysis, characteristics of fluvial sand body morphology and sinuosity of the river, the sedimentation of Guan(1+2) sand sets was defined on the basis of the stratigraphic subdivision and correlation. According to Miall's 16-kind river classification, Guan(1+2) is classified as fine-grade meandering river deposition. The study results indicate that main oil layer of Guan(1+2) is still the abundance zone of remaining oil and non-main oil layer is high saturation zone of remaining oil. Influenced by water injection and gravitational differentiation, abundance zone of remaining oil was formed vertically in middle-to-upper-parts of the reservoir beds and horizontally in the low porosity units on the plane and the area with poor injection-production. Guan(1+2) meandering river deposition model of Gudao Oilfield controls the inner structure and the macroscopic heterogeneity of the sand body in the reservoir beds and the law of space motion of the injection water, thus controls the distribution of the remaining oil.