Abstract:Taking the shale of the paleogene in the Jiyang Depression of Bohai bay basin as the study object, the basic geological characteristics of the shale reservoir were clarified through the detailed observation of the core, the observation of high-pressure mercury injection in the thin section of the rock, and the element analysis of the electron probe.Based on a large number of geochemistry test data obtained from coring Wells in the shale system and shale oil production capacity, the factors of high production and enrichment of shale oil were determined, and the study on the types of shale oil geology showed that the lamination facies rich in carbonate minerals was the most favorable facies for shale oil storage in jiyang depression.The buried depth of lithofacies, diagenetic evolution, formation pressure and total organic carbon content are the key factors to control the enrichment of shale oil. There is a close relationship between the factors of high yield and enrichment of shale oil, and the favorable depth interval of reservoir space (porosity and pore structure) is consistent with the depth interval of shale oil development, that is, the development zone of medium-high evolution and high-porosity zone is in good agreement with the free oil window (3200~4000m).The secondary pore development zones of the retention peak zone in the overpressure section of hydrocarbon fluids are consistent with each other.Based on the original classification of shale oil types, the type of shale oil was made more specific by taking into full consideration the factors of shale oil enrichment, mobility and high yield. The names of the factors, such as source oil, storage oil and production oil, were adopted to highlight the important role of interlayer in the exploration and development of shale oil.