高邮凹陷断层控油气作用的多样性

在探讨高邮凹陷断层发育时期和分布特点的基础上，结合油气分布特点，分析了断层在油气成藏中的作用类型，并探讨了其作用机理。依据断层在油气生成、运移、聚集和分布环节中的作用，把断层分为控源断层、供烃断层、改向断层、成圈断层和调整破坏断层。控源断层控制有效烃源岩展布和生烃时期的早晚，高邮凹陷控源断层下降盘为有效烃源岩分布区，而且西部地区早于东部地区生烃；供烃断层控制油气主运移通道的走势，其陡断面和凸断面为高邮凹陷断裂带油气的主运移通道；改向断层影响油气的富集层位和油气富集区的位置，其对高邮凹陷油气分布的影响存在“分散”和“富集”两种效应；成圈断层控制圈闭的类型及分布；调整破坏断层导致圈闭充满程度和原油物性的改变，高邮凹陷调整破坏断层为盐城期和三垛期活动断层。高邮凹陷断层的多期性和多样性导致断层体系中各断层封闭性在时空上的差异性和多变性，从而形成对油气控制的多面性和复杂性。

Various effects of faults on generation, migration and accumulation of oil/gas in Gaoyou Sag

Based on the analysis of fault activity periods, fault distribution characteristics and hydrocarbon occurrence, the various effects and mechanisms of faults on generation, migration, accumulation and distribution of hydrocarbons were discussed. According to the roles played in the whole process of hydrocarbons from source rocks to traps, the faults could be divided into five types. ①Faults that controlled the distribution of hydrocarbon source rocks and the period of hydrocarbon generation： the effective hydrocarbon source rocks were located in the downdip block of faults with earlier hydrocarbon generation in the western region than that in the eastern region of Gaoyou Sag; ②faults that connected with the hydrocarbon source rocks and controlled the oil/gas migration trends： the steep and convex sections of faults were the main pathways of oil/gas migration in the fault zone of Gaoyou Sag; ③faults that redirected the petroleum migration pathways and controlled the location of hydrocarbon occurrence： the faults caused that there were two opponent roles of distraction and concentration for oil/ gas distribution in Gaoyou Sag; ④faults that controlled the types and distributions of various traps;⑤faults that adjusted and destroyed the oil pools and controlled the enrichment and physical properties of petroleum in the traps： the faults were active during Yancheng Period and Sanduo Period in Gaoyou Sag.It was concluded that the multistage and diversity of faults in Gaoyou Sag resulted in the difference and variety of the sealing ability of faults in time and space, and played the complex and multiple roles on oil/ gas migration and accumulation.