Provenance of Permo‐Carboniferous Sediments Across the Changchun‐Yanji Suture and Its Implications for the Tectonic Evolution of the Eastern Segment of the Central Asian Orogenic Belt

The eastern segment of the Central Asian Orogenic Belt in NE China is considered to have been welded along the Changchun‐Yanji suture following the closure of the Paleo‐Asian Ocean. However, the timing of the closure of the Paleo‐Asian Ocean between the North China Craton (NCC) and the Songliao Terrane remains highly debated. The Permo‐Carboniferous sediments across the Changchun‐Yanji suture are key to addressing this issue. The sediments from the Luquantun Formation are dominated by the Devonian to Carboniferous zircons, with peaks at 376, 354 and 326 Ma. Based on detrital zircon ages and fossil assemblages, the Luquantun Formation was probably deposited during the Early to Late Carboniferous. The detrital zircons generated ε Hf (t) values ranging from −19.0 to +7.4 and were probably derived from the NCC and its northern accretionary belt. In contrast, the detrital zircons from the Fanjiatun, Yilaxi and Yangjiagou formations gave youngest peak ages of 258, 257 and 254–259 Ma, respectively. These formations were probably deposited during the Late Permian, based on these ages and previous studies. These Upper Permian sediments contain zircon ages spanning from the Precambrian to the Palaeozoic, with ε Hf ( t ) values ranging from −22.0 to +12.0, indicating a mixed provenance from the Songliao Terrane to the north and the NCC together with its northern accretionary belt to the south. Based on the provenance analysis presented above, along with the Late Permian flora mixing, collisional granitoids, and metamorphic rocks, the closure of the Paleo‐Asian Ocean probably occurred during the Late Permian, at least in the Changchun area.