Pre-Yanshanian geological events in the northern margin of the North China Craton and its adjacent areas

Abstract：Recent researches on the northern margin of the North China Craton (NCC) and its adjacent areas have been mainly focused on the main pre-Yanshanian tectonic framework and the late Mesozoic tectonomagmatic evolution and lithosphere destruction. This paper gives a brief review on the previous research progress and future prospect in this aspect. The northern NCC has undergone multiple magmatic processes after its cratonization during ~1.8 Ga. Large volumes of 1.35-1.30 Ga mafic sill (dyke) swarms in northern NCC are related to the breakup of the NCC from the Columbia supercontinent and might indicate that the NCC was probably a member of Nena including the Laurentia (North America and Greenland), Siberia and Baltica cratons in the supercontinent. The evolution of the northern continental margin of the NCC was probably initiated at 1.35 Ga. During the Early Paleozoic, the Bainaimiao island arc belt was located to the south of the NCC. At the end of Early Paleozoic, the island arc was accreted to the NCC probably by arc-continental collision. Early-Middle alkaline complexes with emplacement ages ranging from 410-380 Ma in northern NCC are probably related to the extension after arc-continental collision between the NCC and the Bainaimiao arc terrane. From the Late Carboniferous (~320 Ma), the northern margin of the NCC became an Andean-style continental arc due to the southward subduction of the Paleo-Asian oceanic plate beneath the NCC. The southward subduction of the Paleo-Asian oceanic plate also occurred in the Xing-Meng orogenic belt during this period, which resulted in the formation of the Baolidao island arc. Final closure of the Paleo-Asian Ocean and collision between the Mongolian arc terrane and the NCC occurred during the latest Permian~earliest Triassic period with post-collison magmatism from ~250 Ma. During the Late Triassic~Early Jurassic period, the northern NCC is characterized by strong thrusting. In the early Jurassic, the Archean-Paleoproterozoic basement metamorphic rocks were widely exposed. The tectonic framework of the northern margin of the NCC and its adjacent areas was preliminarily established prior to the Yanshanian tectonism and magmatism.