辽东湾北区油气藏特征、主控因素与成藏模式

辽东湾北区已发现3个油气田和十几个含油气构造,主要分布在辽西低凸起及其两侧,油气藏以构造油气藏为主,主要产油层系为古近系沙河街组和前第三系潜山,储层类型多样,油藏多为常压,油气藏以气为主且主要为凝析气,多为超压,油气成藏较晚(主要在12.2~2.6Ma);油气成藏的主控因素是储层和超压,油气藏横向分布主要受储层控制,油气藏纵向分布主要受超压控制;辽东湾北区油气成藏具"凹中隆"型复式成藏特征,"潜山 披覆块状超压油气藏"和"潜山 披覆常压油气藏"是区内主要成藏模式。

An analysis of hydrocarbon reservoir characteristics, main controls and accumulation models in the northern Liaodong bay

Three fields and more than ten hydrocarbon bearing structures have been discovered in the northern Liaodong bay, which are mainly located on Liaoxi low uplift and along its two sides, and are dominated by structural traps. Oil is mainly produced from Neogene Shahejie formation and pretertiary buried hills, and reservoir types are various. Oil reservoirs are mostly in normal pressure, but oil-gas reservoirs usually have overpressure, are dominated by condensate gas and trap hydrocarbon later(mostly 12.2~2.6 Ma).Hydrocarbon accumulation is mainly controlled by reservoir rocks and overpressure, lateral distribution of hydrocarbon reservoirs is mostly controlled by reservoir rocks, and their vertical distribution is controlled by overpressure. Therefore, hydrocarbon accumulation is characterized by a composite type of "uplift in depression" in the northern Liaodong bay, where the main accumulation models are "buried hill draped massive with overpressure" and "buried hill draped reservoir with normal pressure".