准噶尔盆地莫索湾凸起八道湾组低饱和度油藏成因分析

针对准噶尔盆地莫索湾凸起八道湾组油藏前期成因研究缺乏储层物性、隔夹层对含油饱和度低的影响,从孔隙结构、储层物性及非均质隔夹层等方面开展了油藏低饱和度成因分析,剖析了构造幅度对油水分异、储层物性对油水同产区厚度、隔夹层对含油饱和度的影响。结果表明:①孔隙结构差造成储层油水分异不明显、油水置换不完全是八道湾组油藏含油饱和度低的主要原因;②储层低孔隙度与渗透率的物性特征导致油水同产厚度较大是八道湾组油藏含油饱和度低的次要原因;③由于八道湾组并没有形成区域性的、连续的隔夹层,因此,隔夹层对八道湾组油藏含油饱和度低的影响较小。研究结果将为八道湾组的高效开发提供依据,加快探勘开发进程。

Genesis Analysis of Low Saturation Oil Reservoirs in Badaowan Formation of Mosuowan Bulge in Junggar Basin

In view of the lack of reservoir physical properties and the influence of barriers and interlayers on low oil saturation in the previous studies of the genesis of the Badaowan Formation reservoir in the Mosuowan Bulge, Junggar Basin, the analysis of reservoir low-saturation genesis was carried out from the aspects of pore structure, reservoir physical properties and heterogeneous barriers and interlayers, and the influences of structural amplitude on oil-water variation, reservoir physical properties on thickness of oil-water co-producing area, and barriers and interlayer on oil saturation were analyzed. The result shows: (1) The lack of obvious oil-water variation and incomplete oil-water replacement in the reservoir due to poor pore structure are the main reasons for the low oil saturation of the Badaowan Formation reservoir; (2) The relatively large oil-water co-production thickness caused by the physical properties of low porosity and permeability of the reservoir is the secondary reason for the low oil saturation of the Badaowan Formation reservoir; (3) Since the Badaowan Formation does not form regional and continuous barriers and interlayers, the barriers and interlayers have little effect on the low oil saturation of the Badaowan Formation reservoir. The research results will provide a basis for the efficient development of the Badaowan Formation and accelerate the exploration and development process.