石油与天然气地质2025，Vol.46Issue(2)：478-490,13.DOI:10.11743/ogg20250210
四川盆地北部前陆构造叠加区正断层成因机制
Genetic mechanisms of normal faults in the superimposed structural zone in the foreland area of the northern Sichuan Basin
摘要
Abstract
Normal faults are widely distributed throughout the Jurassic strata in the northern Sichuan Basin.However,their genetic mechanisms are yet to be clarified under the continuous compression from foreland basins.A detailed characterization and comparative analysis of faults at various structural locations is conducted using 3D seismic data,and the major controlling factors,genetic mechanisms,and multi-phase structural superimposition process of the Jurassic normal faults are investigated under a compressional tectonic setting.The results indicate that the Jurassic normal faults in the northern Sichuan Basin are a product of tensile strain caused by the folding and bending of strata during uplift.These faults exhibit a uniform and scattered planar distribution,forming numerous graben structures consisting of two or more normal faults with small throws and short displacements that dip in opposite directions.The strikes and numbers of these faults are controlled by the compressional directions and structural phases of surrounding thrust belts,with normal faults perpendicular to the compressional directions formed in each structural phase.The Jurassic normal faults within the northern Sichuan Basin are formed in response to the intracontinental orogeny of the Longmenshan,Micangshan,and Dabashan mountains.Stratum folding and bending formed during the formation of front uplift lead to the development of these faults,with multi-phase,multi-directional tectonic activities in the superimposed structural zone resulting in the formation of complex normal fault assemblages.The Jurassic normal faults in the northern Sichuan Basin are associated structures formed during uplift and deformation in a compressional tectonic setting rather than resulting directly from compressional stress fields.关键词
张应变/成因机制/正断层/叠加构造/前陆盆地/四川盆地Key words
tensile strain/genetic mechanism/normal fault/superimposed structure/foreland basin/Sichuan Basin分类
能源科技引用本文复制引用
苏楠,陈竹新,翟咏荷,潘颖,王丽宁,任荣,张宇轩,谢武仁,武赛军..四川盆地北部前陆构造叠加区正断层成因机制[J].石油与天然气地质,2025,46(2):478-490,13.基金项目
中国石油基础性前瞻性重大科技专项(2023ZZ0202) （2023ZZ0202）
中国石油勘探开发研究院开放课题(2024-KFKT-05) （2024-KFKT-05）
中国石油油气和新能源公司C1类科技专项(2023YQX10101). （2023YQX10101）
