Simulation experiments of the hydrocarbon accumulation in the deep zone of Bonan Sub-sag, Jiyang Depression, Eastern China

Based on the integrated analysis of the actual geological data of Bonan Sub-sag, it is held that there are the favorable conditions for hydrocarbons accumulation in the deep zones of Bonan Sub-sag, and there are two patterns of hydrocarbon accumulation. One is the self-generation and self-storage pattern of Es4, and the other is the down-generation and up-storage pattern of ES3 generating and ES4 storing. The hydrocarbon filling-injecting processes of the two hydrocarbon accumulation patterns are simulated by sand-box experiments, and the controlling factors of hydrocarbon filling-injecting under the two hydrocarbon accumulation patterns are studied. It is shown that the physical properties of reservoir, especially permeability play the key role in whether hydrocarbon can be injected into reservoirs; the oil saturation in reservoirs is mainly influenced by hydrocarbon filling-injecting pressure and filling-injecting amount, and it increases with the increase of them, usually being less than 60% ; the physical properties of reservoir only influence the increasing rate of oil saturation and have little effect on its magnitude; during the hydrocarbon migration process, the physical properties of reservoir influence its force-conditions and therefore not only determine the direction and dominant pathway of hydrocarbon migration, but also influence the increase of the oil saturation to a certain extent.