渤海湾盆地主要凹陷油气富集规律对比研究

A comparative study on hydrocarbon enrichment of main sags in Bohai Bay basin

渤海湾盆地众多生烃凹陷具有裂谷盆地发育演化的共同特征,但各个凹陷又有其独特的构造、沉积特征,从而造成不同凹陷油气富集程度差别极大。通过对渤海湾盆地主要凹陷油气富集差异性、构造及沉积特征的对比研究,认为生烃条件、凹陷的结构特征和断层组合模式、储层与圈闭的最佳组合三大主控因素决定了凹陷油气富集的程度,特别是凹陷的结构特征和断层组合模式对富油凹陷的形成具有至关重要的作用;据此将渤海湾盆地凹陷油气聚集分为"多生多聚型"、"多生少聚型"、"少生多聚型"、"少生少聚型"等4种类型。

There are common evolution features of rifted basin in numerous hydrocarbon-generation sags in Bohai Bay basin, but various sags are very different in hydrocarbon enrichment because of unique characteristics of structure and deposition each. By a comparative study on hydrocarbon en richment and structural and depositional characteristics of the main sags, it can be concluded that hydrocarbon enrichment in each sag depends on three factors, i. e. hydrocarbon generation condition, structural characteristics and fault complex mode, with the latter two particularly important to formation of oil-prone sags. Based on these results, four types of hydrocarbon accumulation can be divided for the sags, including Type ＂more generation and more accumulation＂, Type ＂more generation and less accumulation＂, Type ＂less generation and more accumulation＂ and Type ＂less generation and less accumulation＂.