渤海湾埕北断阶区油气二次运移模式及其对勘探的作用

Hydrocarbon secondary migration modes in Chengbei ladder fault zone in Bohai Gulf and their effects on exploration

油气二次运移是成藏的关键 ,通过对渤海湾埕北断阶区油气二次运移条件及对已发现油气分布特点的分析 ,总结了该区油气二次运移的主要模式 :沿主断层垂直运移 ;沿不整合面和渗透层侧向运移 ;阶梯式运移 ;沿断层走向运移 ;浅层的次级断层对油气再分配等几种 .针对不同区块以相应的运移模式为指导优选了有利钻探目标 ,经庄海 1 x1、庄海 4x1井的钻探验证了研究观点的正确性 .据此提出了 ZDD构造。

The secondary migration is the key factor of hydrocarbon reservoir formation. Through the analyses of the secondary migration of hydrocarbon in Chengbei ladder fault zone in Bohai Gulf and the distribution feature of the found oil and gas, the modes of the hydrocarbon secondary migration in the area are summarized. The main modes are the vertical migration along the major fault, the lateral migration along the unconformity surfaces and permeable formations, the ladder pattern migration, the migration along the fault strike, and oil and gas redistribution of the shallow secondary faults. The favorable drilling targets of different blocks are selected according to corresponding migration modes. The drilling practices of Zhuanghai 1x1 and Zhuanghai 4x1 wells prove the view of this paper. On the basis of the drilling result, it is held that the paleotough at the uplift wall of Zhaobei fault and the reverse drag structure of Neogene system at the downthrow block of Zhaobei fault are favorable exploration belt.