Late Archean-Paleoproterozoic plate tectonics along the northern margin of the North China craton

The North China craton of central Asia is a natural laboratory for investigating early Earth tectonic processes including subduc-tion and large-scale horizontal crustal mo-tions. However, it remains unclear how and when the North China craton formed from the amalgamation of several blocks and orogens including the Archean Western and Eastern blocks, the late Archean Central Orogenic Belt, and the Paleoproterozoic Northern Margin orogen. In this study, we integrated new and existing geological field observations, zircon and baddeleyite U-Pb geochronology, whole-rock geochemistry, and Sr-Nd-C-O isotope analyses along the northern margin of the North China craton to improve our understanding of its late Ar-chean-Paleoproterozoic tectonic evolution. Observations show the Wuchuan ultramafic-mafic complex of the Northern Margin oro-gen contains a mixture of mylonite gneiss, serpentinized ultramafic blocks, and am-phibolite pyroxenite xenoliths. Geochronol-ogy and geochemistry results suggest that the ca. 2.55-2.5 Ga development of the Wuchuan ultramafic-mafic complex was associated with subduction, which was followed by ca. 2.39 emplacement of lamprophyre dikes dur-ing continental rifting. Subsequent Paleopro-terozoic subduction magmatism, continental collision, and post-orogenic rifting between the North China craton and southern mar-gin of the Siberian craton are evidenced by ca. 2.0 Ga arc granitoids, ca. 1.87-1.85 Ga A-type, garnet-bearing granitoids and mafic dikes, and ca. 1.86 carbonatite. Ca. 2.0 Ga collision and ca. 1.87-1.85 Ga rifting were co-incident with orogen-normal left-slip shear. Our findings show that the ca. 1.9 Ga North China-Siberia collision was a key event dur-ing the assembly of the Columbia superconti-nent that occurred via modern plate-tectonic processes.