The configuration and kinematics of fold-thrust belts are essential for clarifying the plate boundary conditions through which ancient orogenic belts evolved. Temporal and spatial variations in extension versus contraction within convergent plate margins are related to changes in plate kinematics and subduction geometry. The Yanshan Mountains, located along the northeastern margin of the North China Craton and bounded by the Central Asian Orogenic Belt to the north and the Pacific subduction zone to the east, underwent multiple phases of intra-continental deformation during the Mesozoic. The issue of whether early Mesozoic deformation was extensional or contractional has remained controversial. New regional structural mapping and detailed sedimentological investigations, coupled with age constraints provided by zircon U-Pb geochronology, provide sufficient temporal and spatial resolution to show that shortening and thrust-top basin systems dominated during the early Mesozoic. Our results show that the Dengzhangzi Basin within the Lingyuan fold-thrust belt developed during the construction of a major Late Triassic Chapeng antiformal-stack duplex system, with episodic, east-vergent forward-breaking thrusts and subsequent ‘beheading’ by out-of-sequence, top-to-east thrusting in the latest Triassic or earliest Jurassic. The neighbouring Guojiadian Basin in the east was generated during top-to-SSE sinistral transpression along the Niuyingzi thrust system in the Middle to earliest Late Jurassic. These results support a new model of early craton decratonization involving (a) thrusting along the northern margin of the North China Craton and (b) transpressional deformation in the east driven by the Central Asian Ocean collision and flat-slab subduction of the Palaeo-Pacific Plate beneath the East Asian continental margin. Our findings suggest that large-scale shortening and crustal/lithospheric thickening, triggered by flat-slab subduction in the North China Craton, were fundamental components of craton decratonization. Subsequent slab roll-back during the Cretaceous led to lithospheric thinning and crustal extension in the North China Craton.

中文翻译：

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燕山的逆冲挤压作用：对华北克拉通早中生代造山作用和去克拉通化的意义

褶皱冲断带的构造和运动学对于阐明古造山带演化的板块边界条件至关重要。会聚板块边缘内伸展与收缩的时间和空间变化与板块运动学和俯冲几何学的变化有关。燕山山脉位于华北克拉通东北缘，北以中亚造山带为界，东以太平洋俯冲带为界，在中生代经历了多次陆内变形。早期中生代变形是伸展还是收缩的问题仍然存在争议。新的区域结构图和详细的沉积学调查，加上锆石 U-Pb 年代学提供的年龄限制，提供足够的时间和空间分辨率来表明在早中生代期间缩短和逆冲盆地系统占主导地位。我们的研究结果表明，凌源褶皱冲断带内的灯杖子盆地是在晚三叠世茶棚反形式叠层双重系统建造过程中发育的，具有间歇性的、东向的前冲冲断和随后的“斩首”。晚三叠纪或最早侏罗纪自上而东的冲断层序。东部邻近的郭家店盆地是在自上而下形成的 我们的研究结果表明，凌源褶皱冲断带内的灯杖子盆地是在晚三叠世茶棚反形式叠层双重系统建造过程中发育的，具有间歇性的、东向的前冲冲断和随后的“斩首”。晚三叠纪或最早侏罗纪自上而东的冲断层序。东部邻近的郭家店盆地是在自上而下形成的 我们的研究结果表明，凌源褶皱冲断带内的灯杖子盆地是在晚三叠世茶棚反形式叠层双重系统建造过程中发育的，具有间歇性的、东向的前冲冲断和随后的“斩首”。晚三叠纪或最早侏罗纪自上而东的冲断层序。东部相邻的郭家店盆地是在自上而下形成的晚侏罗世中至最早沿牛营子逆冲系的SSE左旋压挤作用[J]. 这些结果支持了一个新的早期克拉通去克拉通化模型，包括 (a) 沿华北克拉通北缘逆冲和 (b) 由中亚洋碰撞和古太平洋平板俯冲驱动的东部挤压变形东亚大陆边缘下的板块。我们的研究结果表明，由华北克拉通平板俯冲引发的大规模缩短和地壳/岩石圈增厚是克拉通非克拉通化的基本组成部分。随后的白垩纪板块回滚导致华北克拉通的岩石圈减薄和地壳伸展。