依据三维地震资料,综合钻探成果,运用断层落差法研究断层在古近系沉积期间的活动特征,探讨断层活动特.点对油气富集条件的影响。研究结果表明:断层活动受构造背景控制,在伸展阶段呈“弱-弱-强”变化,具“分时、分段、分区”特点,并分化出长期活动断层、晚期活动断层和早期活动断层。断层活动从运移、囤闭、保存3个方面影响油气富集,长期活动断层控制地层变形能力强,优势运移指向收敛,有利油气聚集,形成断鼻或断块圈闭规模较大;晚期活动断层和早期活动断层控制地层变形能力弱,优势运移指向分散,形成断块固闭数量和规模不及前者。成藏期,控圈断层活动越弱,保存条件越好,越易见油气。铜城断层东侧油气富集条件相对有利。该研究结果可对今后该类型油气藏的勘探部署提供一定的参考。
According to 3D seismic data and drilling results, fault throw method is used to investigate activity char- acteristics of faults in Paleogene system sedimentation period and explore the effect of fault activity characteristics on oil and gas enrichment conditions. The research results show that fault activities show a pattern of "weak, weak and strong" in extending stage, have characteristics of separate time, separate stage and separate district and faults are differentiated into long-term active faults, late time active faults and early time active faults, as the fault activities are controlled by tectonic setting. Fault activities affect oil and gas enrichment in three aspects including transporta- tion, trapping and preservation. Long-term active faults have strong control on formation deformation, have conver- gent favorable migration, are favorable for oil and gas enrichment and can form large-scale fault noses or fault traps. Late time active faults and early time active faults have weak control on formation deformation, have divergent favor- able migration and the number and scale of faulted block traps are smaller than the previous one. In reservoir form- ing period, weaker control on trap-control fault activities indicate better preservation conditions and earlier hydro- carbon show. Oil and gas enrichment conditions on the east flank of Tongcheng fault are relatively favorable. The re- search results provide reference to future exploration deployment of this type of reservoirs.