Abstract: Studies on the sequence stratigraphy of Nanyang Sag shows that the oil and gas accumulation is closely related to the system tracts. There are updip pinch out reservoir in the lower and high system tracts, lens reservoir formed in the subaqueous fan sandbodies, overlay reservoir formed in the sandbodies in the lake expanding system tracts of south steep slope. And there is lens reservoirs in the lower and high system tracts of the deep depression. There are lens, fault-litholigic, fault- anticline reservoirs in LST, fault noses and fault-litholigic reservoirs in HST, overlay reservoir formed in the sandbodies in the lake expanding system tracts of the north of gentle slope break.Combination of the characteristics of the sequence stratigraphy with distribution rules of all kinds of reservoirs lead to the conclusion that the oil and gas accumulation models are based on the sequence stratigraphic frames. The oil and gas accumulation regions are divided into three types: lower system tracts oil and gas accumulation region which are in the north gentle slope break, southern sandstones gas and oil accumulation region, axial deltal oil and gas accumulation region. Medium-short distance migration, medium-short fault and microfissure translocating system and centripetal & vertical migration are the oil and gas accumulation characteristics of north gentle slope break. The sandbodies of the southern sag are connected in the vertical direction and continuous in the horizontal direction. The sealing condition is not very well. Fault-block, fault-lens reservoirs are included to the deltal accumulation belt.

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