目前,世界上新发现了众多深层油气藏,深层油气资源及成藏逐渐成为研究的热点。沉积有机相可以辅助对烃源岩的生烃潜力做出较好的评价,进而指导油气勘探。通过对东营凹陷下始新统沙四段烃源岩沉积特征及沉积环境、有机岩石学、有机地球化学、孢粉相等的分析,主要运用特殊元素比值、有机碳含量、镜质体发射率和孢粉相模式,将沙四段自下而上划分为盐下段的弱还原冲积扇沉积有机相、盐间段的强还原盐湖沉积有机相、盐上段的还原深湖一半深湖沉积有机相3个有机相带。其中,以盐上段的还原深湖一半深湖沉积有机相烃源岩中保存的有机质最佳,具有良好的勘探前景.盐间段次之.盐下段较差.
With many deep oil and gas reservoirs found around the world, the researches are beginning focusing on generation and accumulation of the deep hydrocarbon resources in recent years. Organic facies can assist to make a better evaluation of hydrocarbon potential of source rocks, and then guide oil and gas exploration. The organic facies of hydrocarbon source rocks of the fourth member of Shahejie Formation of Lower Eocene (Es4) is divided into three types according to the data of sedimentary characteristics, sedimentary environment, organic petrology, organic geochemistry and palynofacies, and by using special element ratios, organic carbon content, vitrinite reflectance and palynofacies model. Three types from the bottom to the top are weak reducing alluvial fan organic facies under salt beds, strong reducing salt lake organic facies within salt beds and reducing deep-half deep lake organic facies upper salt beds. In the three types of organic facies, organic matters in hydrocarbon source rocks upper salt beds are best, with good exploration prospects, and those within salt beds go second, those under salt beds last.