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• Transform systems are identified in the Yanshan and northern Taihang belts, NCC. • They are the dextral contraction before 143 Ma and sinistral extension after 129 Ma. • Boundaries of the modified and destructed NCC are defined by the transform systems. • Transition of the transform systems marks the initiation of the destruction of NCC. Mesozoic tectonics of the North China Craton (NCC) is characterized by craton modification and destruction that resulted in varied degrees of craton instability. The change from the end of the latest modification to the start of the final destruction of the NCC is regarded to be related to the subduction and roll-back of the Izanagi plate. However, the timing of this tectonic transition remains debated, and the extent of the area where cratonic destruction occurred is still poorly constrained. The joint part of the Yanshan and Taihang Mountain belts has been viewed as the northwest margin of the destructed eastern NCC. Detailed geological mapping and geochronological studies of this area reveal two groups of transform structures: (1) the dextral transform structures developed before 143 Ma and (2) the sinistral transform structures formed after 129 Ma. The western boundary of the dextral transform structures separate the intact NCC and the modified NCC, whereas the sinistral transform structures define the northwestern and northern boundaries of the destructed NCC. The switching from dextral to sinistral movement occurred at ca. 143–129 Ma, which is roughly coeval with the initial volcanism of the Zhangjiakou Formation, whose age becomes younger eastward. The western boundary of the sinistral transform structures migrated to the east for more than 120 km with respect to that of the dextral transform structures. These indicate that the transition from the end of the latest modification to the start of the final destruction of the NCC occurred in 143–129 Ma. In regional geology, this transition is consistent with the geodynamic setting of the transformation from the Late Jurassic flat-slab subduction to slab roll-back of the Izanagi plate since ~144 Ma. [ABSTRACT FROM AUTHOR]

• Two stages of folds are identified on the northern margin of the North China Craton. • The D 1 folds were crossly superimposed by the D 2 folds and both formed in Paleozoic. • A dynamic transition occurred in middle Paleozoic in the northernNorth China Craton. Accretionary kinematic history of the Central Asia Orogenic Belt (CAOB) remains unclear in previous geological studies. Based on detailed structural analysis of newly identified folds on the northern margin of the North China Craton (NCC), we propose a tectonic model suggesting that Paleozoic accretion of the orogenic belt includes two phases of deformation. The first phase of deformation is oblique collision of the Bainaimiao Arc and the NCC, which was followed by orthogonal subduction of the Paleo-Asian Ocean in the second phase of deformation. The change of plate kinematics is supported by two generations of folding, namely D 1 (D B) and D 2 (D A). Both D 1 (D B) and D 2 (D A) folds developed in the Bayan Obo Group (BOG), a Meso- and Neoproterozoic rift sequence deposited on the passive continental margin of the NCC. D 1 (D B) folds were superimposed by the east-west trending D 2 (D A) folds. The D 1 (D B) folds developed as a result of oblique collision of the Bainaimiao arc and the NCC. The D 2 (D A) folds developed in response to the southward orthogonal subduction of the Paleo-Asian Ocean Plate. They formed between latest Silurian and Early Permian, coeval with the two accretion events at the northern edge of the NCC. Our study suggests that multiphase deformation of sedimentary layers on the subducting plates provide important constraints for kinematic evolution of plate tectonics. [ABSTRACT FROM AUTHOR]