燕山东段下辽河地区中新生代盆山构造演化

摘要

The author discussed the pre-Mesozoic structure background and the Mesozoic-Cenozoic basinmountain structure evolution in the east Yanshan area and Xialiaohe Basin. The author considers that the Mesozoic-Cenozoic structure evolution process in the east Yanshan and Xialiaohe Basin is a alternate process of intracratonic (intracontinental or intraplate)basin-mountain structrue and compression structure in the basement of pre-Mesozoic North China Craton lithosphere. It experienced five periods of basin-moun-tnin evolution(Early and Middle Triassic, Late Triassic to Early Jurassic, Middle and Later Jurassic,Cretaceous and Cenozoic)and five compression deformation stages (the end of Middle Triassic, Early Jurassic, Late Jurassic, Cretaceous and Paleogene). The compression not only resulted in withering or disappearing of the early basins, but also made them deform or be responsible for the basin reversion. The extensions in Middle and Late Jurassic, Cretaceous and Cenozoic resulted in Middle and Later Jurassic fault basin, Cretaceous fault basin and Cenozoic rift basin. The compression and extension appear alternatively, associated Compression structures and extensional structures developed alternatively in the process.%笔者通过分析燕山东段-下辽河地区的前中生代构造背景和中新生代盆山构造演化认为，该区中新生代的构造演化过程是在前中生代华北克拉通岩石图基础上发育起来的克拉通内(陆内或板内)盆山构造与挤压构造的交替演化过程，经历了早-中三叠世、晚三叠世-早侏罗世、中-晚侏罗世、白垩纪、新生代5个盆山构造演化阶段和中三叠世末、早侏罗世末、晚侏罗世末和白垩纪末、老第三纪末5期挤压作用。每次挤压作用都使得早期盆地萎缩或消亡，造成早期盆地反转。中-晚侏罗世、白垩纪和新生代三个阶段的伸展作用形成中-晚侏罗世断陷盆地、白垩纪断陷盆地和新生代裂谷盆地。在这一构造演化过程中，挤压作用和伸展作用交替出现，挤压构造和伸展构造间互发育。