关键词: 深层烃源岩, 沉积有机相, 下始新统, 沙四段, 东营凹陷

Abstract: 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.

Key words: deep hydrocarbon source rocks, organic facies, Lower Eocene, the Fourth Member of Shahejie Formation, Dongying