断块油气田油气运移聚集的一种模式

A Type of Pattern of Oil-Gas Migration and Accumulation of Fault-Block Oil-Gas Field

以东营凹陷的永安镇断块油气田为例，根据油气分布特征及流体性质变化规律探讨了断块油气田油气运移聚集的一种模式。研究区主体部分为一被阶梯状断层切割复杂化的背斜构造，东西向延伸的南掉正断层将其切割成自北向南依次降低的3个台阶，4个含油断块区。早第三纪末东营运动断裂活动期，断裂不仅提供了油气垂向运移的通道，也造成了地层的大幅度的倾斜，油气一方面沿断裂垂向由深部运移至浅部，另一方面横穿断层向相邻断决运聚，形成大量次生油气藏。各断块内部构造低部位油重，高部位油较轻。从邻近油源的低断块到离油源较远的中、高断块区，依次出现油藏、油气藏、纯气藏完整序列，流体性质由油轻气重水咸组合过渡到油重气轻水淡组合。油气分布及流体性质的分带是油气呈阶梯状运移，并遭受次生氧化的结果。

A type of pattern of oil-gas migration and accumulation is discussed on the basis of distribution of petroleum and properties of fluids in the Yonganzhen fault-block oil-gas field. It pointed out that from the lower fault fault-block area close by oil-gas source center to the middle and higher ones in the field,oil pool,oil-gas pool and gas pool occur in proper order,the relative densities of oil and gas become avier and lighter respectively,and the salinity of formation water decrease. The belt distribution characteristics of oil-gas and properties of fluids in this region are the results of oil and gas migration in the manner of ladder stairs and secondary oxidation in the process.