在系统研究贝中次凹断裂的发育及形成演化特征的基础上，分析了断裂对贝中次凹油气成藏条件的控制作用。贝中次凹自下而上划分为断陷构造层、断-坳转化构造层和凹陷构造层。根据断裂与各构造层的切割关系及运动学特征，以 T22为界将贝中次凹发育的断裂划分为上、下两个断裂系统，进一步划分为早期伸展断裂、中期张扭断裂、早期伸展中期张扭断裂和长期活动断裂4种断裂类型。各个历史演化时期控制着不同成因的断裂发育，在上部断裂系统中发育了由于泥岩密度反转作用所形成的非构造成因的断裂密集带，断裂的形成和演化影响主力烃源岩的分布和热演化程度，形成多种类型的圈闭，为油气运移提供良好地运移通道。长期继承性活动断裂与上部断层系构成的密集带是油气运聚成藏的有利指向区。%On the basis of the systematic research of the developing and evolving characteristics of faults in Beizhong sub-depression, the impact of faults on the gas-bearing property in Beizhong sub-depression was analyzed. Each evolution period controls the development of fault with different causes. Nonstructural fault densely zone was formed in the upper fault system because of mudstone density reverse. The formation and development of fault impacted the distribution and thermal evolution degree of chief source rock, formed kinds of traps, and provided good migration channel. The densely zone made by long term succeed activity fault and upper fault structure were the favorable areas of hydrocarbon migration and accumulation.
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