乌尔逊凹陷北部大一段断层封闭性演化及对成藏的控制作用

Fault Closure Evolution of Da I Member in Northern Wuerxun Sag and Its Controlling Effect on Reservoir Formation

在乌尔逊凹陷北部大一段断层发育及活动特征研究的基础上,利用断层带填充物岩性和泥岩塑性变形强度评价了其主要断层在大一段的垂向封闭性,通过断层封闭性及其演化史与油气运聚成藏之间关系研究认为,只有晚期和继承性断裂才能作为南屯组源岩的油气运移通道,大一段内较好的垂向封闭性有利于油气在南二段聚集,与断裂有关的圈闭是乌尔逊凹陷北部的主要圈闭类型。

Based on studying fault development and movement characteristic of Da I Member in northern Wuerxun Sag, this paper evaluates the vertical closure of main faults in Da I Member using filler lithology in fault belt and shale plastic deformation strength. Through study on the relation between fault closure and its evolution history and hydrocarbon migration, accumulation and reservoir formation, it concludes that only later and inherited fracture can act as hydrocarbon migration channel of source rock in Nantun Member, nice vertical closure in Da I Member is favorable for oil and gas accumulating in Nan II Member, and trap relative to fracture is the main trap type in northern Wuerxun San.