辽河坳陷台安-大洼断裂带新生代构造演化及油气成藏

Cenozoic Tectonic Evolution and Hydrocarbon Accumulation of Taian-Dawa Fault Zone,Liaohe Sag

台安-大洼断裂带油气资源丰富,是辽河坳陷最重要的含油气区带之一。为探讨该区构造演化与油气成藏的关系,通过对断裂带的构造特征及演化进行分析,开展油气成藏模式研究,揭示了台安-大洼断裂带新生代构造演化对油气成藏的影响,进而指导断裂带勘探领域及目标的优选。研究结果表明:台安-大洼断裂带同时具有伸展拉张和走滑反转的双重构造特点,其构造演化划分为断陷期、断陷和右旋走滑期、坳陷期3个阶段。构造演化对断裂带的油气成藏具有重要的控制作用,其控制了沉降中心由北向南迁移、储集体发育、复式油气输导体系的形成以及断层活动与油气排烃的匹配关系。明确了断裂带北部和南部的油气成藏模式及有利勘探区,为断裂带下一步勘探方向部署提供了依据。

With abundant oil and gas resources,Taian-Dawa Fault Zone is one of the most important hydrocarbon-bearing zones in Liaohe Sag.The tectonic characteristics and evolution of the Fault Zone were analyzed to explore the relationship between the tectonic evolution and hydrocarbon accumulation in the Fault Zone.A study was performed on hydrocarbon accumulation mode to work out the effect of Cenozoic tectonic evolution on hydrocarbon accumulation in Taian-Dawa Fault Zone,providing guidance in the optimization of exploration fields and targets of the Fault Zone.The results of the study showed that Taian-Dawa Fault Zone was characterized by both extensional and strike-slip inversed tectonics and its tectonic evolution was divided into three stages:faulting period,dextral slip period and depression period.The tectonic evolution significantly controlled the hydrocarbon accumulation in the Fault Zone,specifically controlling the migration of subsidence center from north to south,the reservoir development,the formation of complex petroleum migration pathways,and the matching between fault activities and hydrocarbon discharge.The hydrocarbon accumulation patterns and favorable exploration areas in the north and south of the Fault Zone were identified,providing a basis for the next exploration deployment in the Fault Zone.