辽河西部凹陷滩海地区古近系复合含油气系统特征与演化

辽河西部凹陷滩海发育3个含油气系统,多个含油气系统在其形成过程中共享某些成藏地质条件,构成一藏多源、一源多藏的古近系复合含油气系统。通过对含油气系统静态要素和动态作用过程的描述,认为古近系复合含油气系统油源充足,成藏条件匹配良好,油气资源丰富;东营组、馆陶组沉积时期和明化镇组沉积末期是复合含油气系统油气成藏、运聚的关键时刻,决定了油气生-运-聚高峰、圈闭形成和油气保存。系统内发育3类圈闭组合带,即潜山披覆型、陡坡型和缓坡型复合圈闭带,油气充注后形成相应的复合油气聚集带,发育特有的油气藏类型组合。今后应以复合油气聚集带的理念为指导,加速该区的油气勘探。图4参19

Characters of the Eocene composite petroleum system in the west sag of the beach area, Liaohe Depression

There are three hydrocarbon systems in the west sag of beach area in Liaohe Depression, and they shared the same sources and accumulated hydrocarbon of mixed origin during their development. The analysis of static elements and dynamic process indicates that the Eocene composite hydrocarbon system is petroliferous because it has high-grade source rocks and has experienced optimal hydrocarbon evolution process. The critical periods for trapping, migration, accumulation and preservation of hydrocarbon are during the deposition of Edi+2 , Ng and at the end of Nm. Three types of composite trap-zones are observed and they are buried hill, steep-slope and flat-slope,respectively. Composite hydrocarbon-bearing units should be the exploration targets in the study area in future exploration.