海洋地质前沿2026，Vol.42Issue(4)：28-37,10.DOI:10.16028/j.1009-2722.2025.143
走滑伴生断裂构造断裂力学分析及其指示意义
Failure mechanism of secondary fractures associated with strike slip fault and its stress field implication:a case study of Miaoxinan Uplift,Bohai Bay Basin
摘要
Abstract
Formation of secondary tensile fractures can be attributed to stress perturbations that developed around pre-existing main strike slip fault.These secondary fractures are generally oriented oblique to the pre-existing flaw,and their orientations tend to follow a striking similar pattern.To further study the common features of the secondary fracture,fracture mechanics were used to interpret stress field conditions responsible for the secondary fractures of the major strike-slip fault.A tentative geomechanical model was established by evaluating the correla-tion between their geometric information and local stress state.An ideal homogeneous displacement was con-sidered along the main part of large-scale strike-slip faults.In an ideal state,the displacement of a strike slip fault is approximately the same in its main section,while at the end of the strike slip fault,it is gradually absorbed by the deformation of the rock masses on both sides,which is referred to viscoelastic behavior of the rock.The LE-FM(linear elastic fracture mechanism)and CEZ(cohesive end zone)models in fracture mechanics were applied for the main section and the end of strike-slip fault,respectively.Results show that the angle between secondary fracture and strike slip in a strike slip fault system can reflect the proportional relationship between shear stress and normal stress near strike slip.The northern high area of the Penglai 20-A Structure in the Miaoxinan Uplift is located in the strike slip end area.By applying these research achievements to the Miaoxinan uplift,although the strike-slip displacement and fault throw in the northern high area of Penglai 20-2 Structure are relatively small,the characteristics of the secondary fracture angles indicate compressional stress state of the area.Additionally,the re-gion sit on a imbricated zone of dextral left-stepping strike-slip fault system,which not only controls the forma-tion of structural traps,but also ensures effective side sealing conditions in the area.The research results contrib-ute to the understanding of the development mechanism of associated faults in strike slip fault systems,providing a new quantitative approach for the rational explanation of the geometry and stress field of the secondary frac-tures in the Miaoxinan Uplift.关键词
走滑断裂系统/断裂力学/伴生断裂几何特征/应力场特征/渤海湾盆地Key words
strike-slip fault/failure mechanism/geometry of secondary fractures/stress field state/Bohai Bay Basin分类
海洋科学引用本文复制引用
苏凯,郭奕杉,任健,李婷婷,朱勇超..走滑伴生断裂构造断裂力学分析及其指示意义[J].海洋地质前沿,2026,42(4):28-37,10.基金项目
中海石油(中国)有限公司"七年行动计划"重大科技专项课题"渤海油田上产4000万吨新领域勘探关键技术"(CNOOC-KJ 135 ZDXM 36 TJ 08 TJ) （中国）
