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When the Paleo‐Asian Ocean closed and the Paleo‐Pacific subduction started in NE China remains controversial. To constrain these key issues, we carried out zircon U‐Pb‐Hf isotopic and whole‐rock geochemical studies of Early Mesozoic igneous rocks in central southern Jilin Province, NE China. Early Mesozoic igneous rocks in region were formed at three stages: the middle Triassic (246 Ma), the late Triassic (219–220 Ma), and the early Jurassic (172–194 Ma). Middle Triassic trachyandesites in southern Jilin Province were solely generated through partial melting of ancient lower crust of the North China Craton (NCC), implying ongoing southward subduction of Paleo‐Asian Ocean Plate beneath the NCC at this time. Late Triassic trachyandesites in southern Jilin Province were derived from the magma mixing/mingling of the NCC lithospheric mantle and juvenile eastern Central Asian Orogenic Belt crustal sources. Late Triassic hornblende gabbros in central Jilin Province were derived from depleted lithospheric mantle previously metasomatized by subduction‐related fluids. Coeval adakitic granodiorites were likely produced through the partial melting of thickened juvenile lower crust. Spatially, these rocks occurred on both sides of the Solonker‐Xra‐Moron‐Changchun Suture Zone and record N–S directed extension accompanied by the final closure of the Paleo‐Asian Ocean. Early Jurassic andesites were produced through mixing/mingling between partial melts derived from eastern Central Asian Orogenic Belt lithospheric mantle and ancient NCC crust. In contrast, Early Jurassic felsic rocks, including A‐type granites, were derived from the partial melting of Neoproterozoic accreted lower crust, jointly implying an extensional setting as the result of the initial subduction from Paleo‐Pacific Plate at this time. Key Points: Three magmatism stages are recognized in central southern Jilin Province, NE ChinaMiddle–Late Triassic rocks record the subduction and termination of Paleo‐Asian Ocean tectonic regimeEarly Jurassic rocks record the onset of the Paleo‐Pacific tectonic regime [ABSTRACT FROM AUTHOR]

The Late Paleozoic–Mesozoic tectonic evolution in the northeastern (NE) Asian continental margin has been a controversial issue. Accretionary complexes (ACs) and sedimentary formations, as the direct material records of the reconstruction of plate subduction history and surface response, respectively, are the categorically ideal indicators to explore tectonic evolution of the NE Asian continental margin. This study reviews recent geological and geophysical advances about the crustal structures beneath the massifs and ACs such as the Yuejinshan and Raohe ACs and conducts a detailed dissection on lithology, degree of metamorphism and deformation, deep crustal structure, and formation time of these fossil ACs. These results, together with the coeval sedimentary formations and igneous rock associations, provide new insights for Late Paleozoic-Mesozoic tectonic evolution of NE Asian continental margin, i.e., the NE Asian continental margin experienced the evolution of two tectonic regimes during the Late Paleozoic–Mesozoic: 1) the stage of the Paleo-Asian Ocean tectonic regime, including a passive continental margin in the early stage of the Late Paleozoic, an active continental margin in the early Permian, and tectonic transition in the Triassic. A paleo-ocean occurred between the Jiamusi Massif and an unnamed massif during the Late Devonian–late Permian; and 2) the stage of the Paleo-Pacific tectonic regime, including the subduction onset of the Paleo-Pacific Plate beneath Eurasia in the Early Jurassic, the accretion and emplacement of the Jurassic ACs during the Late Jurassic–early Early Cretaceous, and the continuous westward subduction during the Late Mesozoic. The Yuejinshan AC was the product of the Paleo-Asian Ocean tectonic regime and formed during the Late Devonian–early Permian. Its final emplacement occurred in the late Permian. The Raohe AC was the product of the Paleo-Pacific tectonic regime and experienced the following stages: 1) the formation of seamounts and deposition of the terrigenous clastic sediments in the Middle–Late Jurassic; 2) the seamount–Eurasia collision in the Late Jurassic; 3) the northward migration of the embryo of the Raohe AC during the Late Jurassic–early Early Cretaceous (160–140 Ma); 4) the deposition of the early Early Cretaceous sediments; and 5) the final emplacement of the Raohe AC in the late Early Cretaceous (140–130 Ma). • Sedimentary strata and accretionary complex reveal the evolution of the NE Asia. • NE Asia was in a passive continental margin setting in the early Late Paleozoic. • E Asia was an active continental margin setting in the early Permian. • The subduction of the Paleo-Pacific Plate beneath Eurasia began in the Early Jurassic. • The Yuejinshan and Raohe accretionary complexes formed in different tectonic [ABSTRACT FROM AUTHOR]