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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]

A big mantle wedge (BMW) is an important deep Earth structure that has implications for our understanding of geodynamic processes. The eastern and northeastern Asian BMWs have been extensively studied in the past two decades. This paper reviews evidence for the age, formation, spatial extent, and geodynamic effects of BMWs, with the aim of distinguishing between two BMWs. The eastern Asian BMW initially formed in the late Early Cretaceous and was active from 110 to 55 Ma due to rollback of the subducted Paleo-Pacific Plate and eastward-directed deep mantle flow. This BMW affected the entire eastern Asian continental margin and controlled the late Mesozoic–early Paleogene tectonic evolution of the margin, including destruction of the North China Craton and reworking of continental crust in South China. The northeastern Asian BMW has been active from 20 Ma to the present-day due to rollback of the subducted Pacific Plate and eastward mantle flow. It has mainly affected northeast Asia and resulted in different types of Cenozoic intraplate volcanism and occurrence of earthquakes with deep epicenters. • Eastern (E) and northeastern (NE) Asian big mantle wedges (BMW) are identified. • E Asian BMW formed in late K1 and controlled late Mesozoic-early Cenozoic evolution. • NE Asian BMW formed at ca.20 Ma and controlled intraplate volcanism and earthquakes. [ABSTRACT FROM AUTHOR]