摘要
前陆逆冲带扩展方式是理解造山带生长的关键。四川盆地东缘、北缘和西缘分别发育不同时代和不同构造背景下形成的武陵山-华蓥山、大巴山和龙门山前陆逆冲带,前人对他们的结构和构造运动学进行了详尽的研究。本文在总结这些研究的基础上,揭示武陵山-华蓥山、大巴山和龙门山三条前陆逆冲带的结构分带均表现为从厚皮逆冲构造至薄皮逆冲构造组合的变化,构造解析表明结构分带是断层-褶皱关系主导的指向前陆盆地方向共轴递进扩展作用的结果。同时,在前陆逆冲带扩展分析基础上,总结了四川盆地盆缘共轴扩展、非共轴叠加复合扩展和联合构造扩展三种前陆逆冲带扩展方式。结合阿巴拉契亚、科迪勒拉、阿尔卑斯、喜马拉雅、比利牛斯山等经典造山带前陆逆冲带扩展的研究现状,提出前陆逆冲带扩展研究中存在古构造应力场的σ2悖论、应力-应变(σ-ε)关系难以建立和系统不平衡等问题,并认为这些问题是未来定量化约束前陆逆冲带扩展,进而解决造山带生长构造动力学研究的主要挑战。
Propagation of the foreland thrust belt is the key to understand the growth of orogenic belt.Xuefeng-Huaying,Daba and Longmen Shan foreland thrust belts formed in different times and different tectonic settings are developed in the eastern,northern and western margins of Sichuan basin,respectively.Previous researches have been focusing on their tectonic composition and kinematics.Summarizing these of the studies,this paper reveals a transformation of structural assemblage from thick-skinned thrust to thin-skinned thrust for all three foreland thrust belts.Further structural analysis shows that the structure assemblages and their transformation are dominated by fault-related fold with foreland basin-pointing coaxial progressive propagation.Three types of propagation of foreland thrust belt,i.e.,coaxial,non-coaxial superimposed composite and composite propogations,are proposed by summarized kinematics propagation of the foreland thrust belts.Meanwhile,integrated with the studies of propagation of the classical orogenic belts,such as Appalachian,Cordillera,Alpine,Himalayan and Pyrenees,three scientific issues for the propagation of foreland thrust belt,i.e.,σ2paradox of paleotectonic stress field,difficulty in establishing the stress-strain(σ-ε)relationship and system structural imbalance,are suggested.These of the scientific issues are the main challenges to quantitatively constrain foreland thrust belt propagation and to understand the growth dynamics of orogenic belts in the future.
作者
颜丹平
邱亮
孙铭
周志成
孔若颜
张已
王为
宋华杰
孔霏
都超
林霄晗
YAN Danping;QIU Liang;SUN Ming;ZHOU Zhicheng;KONG Ruoyan;ZHANG Yi;WANG Wei;SONG Huajie;KONG Fei;DU Chao;LIN Xiaohan(State Key Laboratory of Geological Process and Mineral Resources,China University of Geosciences,Beijing 100083,China)
出处
《地质学报》
EI
CAS
CSCD
北大核心
2022年第10期3314-3331,共18页
Acta Geologica Sinica
基金
国家自然科学基金项目(编号42030306,41972206)资助的成果。
关键词
前陆逆冲带扩展
四川盆地
共轴扩展
非共轴叠加复合扩展
联合扩展
propagation of foreland thrust belt
Sichuan basin
coaxial propagation
non-coaxial superimposed composite propagation
composite propagation
