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金湖凹陷是苏北盆地第二大产油凹陷，但各区带油气富集程度分布不均。分析表明，油气二次运移对油气富集程度有较大影响。基于油气二次运移的驱动力为水动力和浮力两类认识，通过对凹陷油田水性质、地下古水流形式和地层流体压力系统特征分析，排除了水动力是油气二次运移的主动力；依据油水界面张力、孔喉半径和润湿角等参数，计算了阜宁组输导层在关键时刻的毛细管阻力并与浮力相比较，得出二级构造带油气侧向二次运移的驱动临界条件，发现油相连续长度远小于含油带宽度，且临界油相长度小的地区油气较富集（反之，则较贫）。因此认为油相静浮力为本区油气二次运移的主动力，并由此指出凹陷油气二次运移方向与有利聚集部位。
The Jinhu depression is the second oil-producing depression in the Northern Jiangsu Basin, but the distribution of oil and gas in each zone is unevenly distributed. The analysis shows that the secondary migration of hydrocarbons has a great influence on the degree of hydrocarbon enrichment. Based on the understanding of hydrodynamics and buoyancy, the driving forces for the secondary migration of oil and gas are the main motivation for the secondary migration of oil and gas by the analysis of the water properties of the oilfields, the paleo-ancient underground water flow patterns and the characteristics of the fluid pressure system in the formation. ; Based on the parameters of oil-water interfacial tension, pore throat radius and wetting angle, the capillary resistance of the Funing Formation at critical moment was calculated and compared with the buoyancy to obtain the second-order lateral migration of oil and gas in the secondary structure zone Driving critical conditions, it was found that the continuous length of the oil phase is much smaller than the width of the oil-bearing zone, and that oil and gas are more concentrated in regions where the length of the critical oil phase is smaller (and vice versa). Therefore, it is considered that the hydrostatic buoyancy of the oil phase is the main force of secondary migration of oil and gas in the area, and the secondary migration direction and favorable accumulation site of the sag are pointed out.