东营凹陷古近系红层油气来源及勘探潜力分析

Origins and Exploration Potential of the Hydrocarbons from the Paleogene Red Rocks in the Dongying Sag

利用沉积学和地球化学相结合的研究方法,分析了东营凹陷古近系Es4下、Es4上和Es3下3套烃源岩基本特征及其分布规律。在此基础上进一步研究了红层中已发现原油的物理性质、族组分和生物标志化合物特征,并对红层原油类型进行了划分,通过油源对比,明确了每类原油的来源。研究表明,红层原油的主力油源层不仅仅只有Es4上和Es3下2套烃源岩,以往认识较为薄弱的Es4下烃源岩也做出了较大贡献。综合分析认为,东营凹陷古近系红层具有较大的勘探潜力,为近期增储上产的主要领域。

Through the combination of sedimentological and geochemical analyses,characteristics and distribution rules of the Paleogene source rocks of Lower Es4,Upper Es4 and Lower Es3 Members are analyzed in this paper.Then the physical properties,group compositions and biomarker features of the discovered oils in red rocks are further studied.The oils in the red rocks can be divided into different types.On the basis of oil-source correlation,the origins of the oils are determined.The results show that not only Upper Es4 and Lower Es3 Members,but Lower Es4 Member which was poorly understood in the past make great contributions to oil formation in red rocks.It can be concluded that Paleogene red rocks in the Dongying sag have great exploration potential.They will be the major areas for reserve and production increase in the near future.