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延吉盆地是吉林省东部的一个山间断陷盆地，其东部坳陷下白垩统大拉子组一、二段为天然气的区域性盖层，盖层的排替压力在１１～１３ＭＰａ范围内，属强封闭能力盖层。研究区断层发育，断层在大一、二段内封闭性好，在下白垩统铜佛寺组内封闭性差；边界断层封闭性差，盆地内部断层封闭性从古至今逐渐变好。研究区主要储层为铜佛寺组和大一、二段，均属低孔、低渗储层。通过对古流体势场的恢复发现，德新凹陷的油气运移以汇聚流形式为主，清茶馆凹陷的油气运移以发散流和平行流形式为主。根据生、储、盖、断层及流体势场等特征的研究，总结出东部坳陷油气运聚模式有３种，即背斜聚敛型油气运聚模式、断层部分截流型油气运聚模式和汇聚流运移断层泄漏型假聚集模式。
The Yanji Basin is a mountain rift basin in the east of Jilin Province. The first and second member of the Lower Cretaceous Dalazi Formation in the eastern depression are regional cap rocks of natural gas. The displacement pressure of cap rock is in the range of 11 ~ 13 MPa Strong sealing ability of the cover. The faults in the study area are well developed. The faults have good sealing in the first and second sections, and have poor sealing within the Lower Cretaceous Tongfosi Formation. The sealing of the boundary faults is poor, and the fault sealing inside the basin has become better since ancient times. The main reservoirs in the study area are the Tongfosi Formation and the first and second sections, all of which are low-porosity and low-permeability reservoirs. Through the restoration of the paleo-fluid potential field, it is found that the hydrocarbon migration in the Dexin depression is dominated by convergent flow and the hydrocarbon migration in the Qingcha depressions is mainly divergent and parallel flow. Based on the study of the characteristics of raw, reservoir, cover, fault and fluid potential field, it is concluded that there are three kinds of hydrocarbon migration and accumulation modes in the eastern depression, that is, the anticlinal convergent-type hydrocarbon migration and accumulation mode, the fault-partially cut-off type hydrocarbon migration and accumulation mode and the convergence Flow migration fault leakage type fake aggregation model