Based on systematic analysis of hydrocarbon accumulation drive and resistance, we applied numerical simulation and geological statistics to construct geological model as well as mathematic model of hydrocarbon dynamics for sand lens reservoir, and to simulate hydrocarbon accumulation process.spacerun: yes"> The research results show that major accumulation drive consists of capillary pressure difference between sandstone and mudstone, diffusion power resulted from hydrocarbon generation in mudstone and expansion power caused by hydrocarbon generation in mudstone. spacerun: yes"> space prefix = o ns = "urn:schemas-microsoft-com:office:office" />