沙南凹陷沙中构造带油气成藏特征及主控因素分析

Analysis on oil and gas accumulation features and main controlling factors of Shazhong structural belt in Shanan Depression

江涛 李慧勇 茆利 王保全 许鹏

中海石油（中国）有限公司天津分公司渤海石油研究院，天津 300452

Bohai Oilfield Research Institute, Tianjin Branch of CNOOC Ltd., Tianjin 300452, China

沙南凹陷是渤海西部海域潜在的富生烃凹陷，但油气的发现量与生烃量差距甚远，成藏特征复杂，油气成藏主控因素认识不清。文中在综合研究该地区的烃源岩、储盖组合、油气运移特征的基础上，指出构造对油气成藏具有重要的控制作用。构造作用通过控制凹陷的构造格局来影响烃源岩的演化和分布，同时又控制和影响圈闭的形成、砂体的发育，源￣圈￣砂共同决定油气的聚集成藏。近源找砂，“自生自储型”砂体是该区下一步油气勘探的有利勘探方向。依靠油气初次运移近源成藏，沿断层面侧向及垂向复合输导是该区主要的油气成藏模式。

Shanan Depression is a potential rich hydrocarbon generation depression in western Bohai sea, but oil and gas discoveries are far from quantity of hydrocarbon generation, oil and gas accumulation features are complex and main controlling factors are not clear. Based on the integrated study of source rock, reservoir-cap assemblages and hydrocarbon migration characteristics, this paper pointed out that structure had mainly control effect on oil and gas accumulation. Tectonic action influenced the distribution and evolution of source rock by controlling the structural framework of depression, meanwhile, it controlled and influenced the formation of trap and development of sandbody, source-trap-sand codetermined oil and gas accumulation. Proximal sand, "source and reservoir in the same bed" sandbody are the most beneficial exploration direction of next oil and gas exploration in study area. Depending on the primary migration of oil and gas proximal accumulation, the composite migration along the fault plane laterally and vertically is the main pattern of oil and gas accumulation.

10.6056/dkyqt201406003