准噶尔盆地车排子凸起新近系沙湾组油藏特征及成藏主控因素

Characteristics and hydrocarbon accumulation controlling factors of Neogene Shawan Formation reservoir in Chepaizi uplift,Junggar Basin

对准噶尔盆地车排子凸起新近系沙湾组已发现油藏从层位、规模、油性、物性、物源、类型等方面进行了梳理和总结。沙湾组共发育岩性、断层-岩性、断鼻三类圈闭,储层特征与油藏规模存在差异,油性分布较复杂。在明确沙湾组复杂油藏特征的基础上,结合典型油藏解剖,认为长期继承性的古隆起、高效的毯状砂体输导层、断层纵横向的封闭性、储集层物性的差异、多源多期成藏过程及不同的保存条件是沙湾组油气藏类型多样、油性复杂的主要控制因素。根据上述认识,预测毯状砂体侧向尖灭带为有利的油气聚集区,从实钻效果看,该区带内油气显示丰富,展现出较好的勘探前景。

The characteristics of the Neogene Shawan Formation reservoirs in Chepaizi uplift are summarized and analyzed according to their layers,sizes,oil qualities,physical property,origins,and types.Lithological,fault-lithological and fault nose traps are the major traps where Shawan Formation was developed.Reservoir characteristics and sizes vary in different reservoirs.The distribution of oil character is very complex.Based on an analysis of the typical reservoirs,the authors hold that long-term inherited paleouplift,efficient blanket-like sand body,fault sealing properties,difference of litholoies and physical properties,and multi-source and multistage accumulation together with storage condition constitute the main controlling factors for the hydrocarbon accumulation.On such a basis,it is pointed out that the blanket sand’s lateral pinch zone is the favorable oil accumulation zone.Drilling reveals that the area possesses rich oil resources and shows good prospect for exploration.