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The central Inner Mongolia, located at the intersection of the northern margin of the North China Craton (NCC) and the Central Asian Orogenic Belt, is crucial for deciphering the Late Palaeozoic tectonic evolution associated with the subduction and closure of the Palaeo‐Asian Ocean (PAO). Our study focused on petrology, detrital zircon LA–ICP–MS U–Pb geochronology and whole‐rock geochemistry for the Late Carboniferous to Permian sandstones within the Shuanmazhuang, Dahongshan, Naobaogou, and Laowopu formations in Siziwang Banner, central Inner Mongolia. This comprehensive analysis shed light on the dynamic interplay between the NCC and the South Mongolia Block. Detrital zircon U–Pb ages in investigated samples mainly cluster between 250 and 2650 Ma, with significant peaks at 2.4–2.5 Ga, 1.8–2.0 Ga, 400–430 Ma, and 250–320 Ma, respectively. The geochemistry data are characterized by SiO2 contents (56.29–77.95 wt. %), Na2O / K2O ratios (0.45–1.58) and SiO2/Al2O3 ratios between 4.33 and 7.44. Moreover, they exhibit the slight enrichment in large ion lithophile elements (Rb and Ba) and the depletion in high field strength elements (Nb, Ta, Th, and U). These facts indicate that the sedimentary detritus predominantly originates from felsic sources, probably deriving from the Late Carboniferous–Permian continental island arc‐related intermediate‐acid igneous rocks, the Late Ordovician‐Silurian magmatic rocks in the Bainaimiao arc and the basements of the NCC. Furthermore, our present results also suggest that during the Early–Middle Permian, accelerating oceanic crust subduction triggered significant magmatic events in Siziwang Banner, leading to rapid uplift and the erosion of arc magmatic rocks, as well as the abundant corresponding sediments. Subsequently, the gradual convergence and eventual collision between the NCC and the Southern Mongolian Block took place at the end of the Permian, representing final closure of the PAO. [ABSTRACT FROM AUTHOR]

As one of the most representative Paleoproterozoic orogenic belts in the North China Craton, the Jiao-Liao-Ji Belt is of great significance to explore the Paleoproterozoic tectonic evolution of the North China Craton, as well as the convergence process of the Columbia Supercontinent. In this study, we present new geochronological and geochemical data of Paleoproterozoic meta-mafic rocks in the Southern Jilin Province, NE China. Our primary objective is to further constraint the formation and evolution of the Jiao-Liao-Ji Belt. The zircon U–Pb dating reveals that the meta-mafic rocks crystallized at 2.2–2.0 Ga, followed by a metamorphism occurring at ~ 1.9 Ga. Additionally, most of the mafic rocks display moderate fractionation in both light rare earth elements (LREEs) and heavy rare earth elements (HREEs), suggesting their association with an arc setting. Furthermore, the rocks also display an enrichment in large ion lithophile elements (LILEs) such as Cs, Rb, Ba, and Pb, and depletion in high field strength elements (HSFEs) including Nb, Ta, Zr, and Ti. These geochemical characteristics suggest a back-arc setting, indicating that the meta-mafic rocks originated from asthenospheric mantle that was metasomatized by fluids or melts derived from the subducting slab. Notably, a shoshonitic metabasalt exhibits trace element and REEs patterns that resemble those of ocean–island basalts. This suggests that the shoshonitic metabasalt was formed in an oceanic island environment, likely generated from the asthenospheric mantle. Combining these findings with previous studies, we can conclude that the Jiao-Liao-Ji Belt is associated with arc–continental collision, indicating the presence of a modern-type plate tectonic regime in the northeastern North China Craton during the Paleoproterozoic period. [ABSTRACT FROM AUTHOR]

Typical ophiolitic rock assemblages such as siliciclastic rocks, basalts and gabbros, together with the subduction-related intermediate-acidic intrusive rocks, are newly discovered in the Tongjiang-Fuyuan area of the Heilongjiang Provence, NE China. To determine the formation age and genesis of the mafic rocks (basalts and gabbros) and intermediate-acidic intrusive rocks (granodiorites) in the area, as well as their geodynamic settings, the whole-rock geochemical analysis and zircon LA-ICP-MS U-Pb dating were carried out. Zircon U-Pb results suggest that the granodiorites are 93–95 Ma and gabbro is 95 Ma, respectively. Geochemical results show that the gabbros and basalts exhibit characteristics of ocean island basalt (OIB) affinity and are typically related to having originated from mantle plumes. While the granodiorites show the nature of the island-arc magmatic rocks and may originate from the lower crust. Based on the coeval igneous rock associations and regional tectonic evolution, we conclude that the late Cretaceous magmatic rocks in the Tongjiang-Fuyuan area are the product of continuous subduction of the Palaeo-Pacific plate and reflect the subduction rollback process of the Palaeo-Pacific plate. [ABSTRACT FROM AUTHOR]