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Tracing coupled ocean closure and intra-continental orogenic processes using tectonomagmatic thermal events is important for performing plate reconstructions. In this study, we collected geochronological data obtained from Jurassic–Early Cretaceous volcanic sequences in the Great Xing apos; an Range (GXR) and compared and merged the data to obtain a better understanding of the timing of volcanism in the GXR. Jurassic–Early Cretaceous volcanism, which is mainly represented by the Tamulangou, Manketouebo, and Manitu formations, are ubiquitous in the GXR and do not contain a magmatic hiatus. Thus, 'diachronous' volcanism did not occur in the GXR. The volcanic sequences in these formations are also slightly ambiguous and therefore cannot be used to determine the timing of volcanism. However, absolute ages and rock assemblages can provide better constraints on this timing. Combined with data from Jurassic–Early Cretaceous tectonomagmatic thermal events in Mongolia, Siberia, and NE China, we re-evaluated the influences of the Jurassic–Early Cretaceous closure of the Mongol–Okhotsk Ocean (MOO), as well as the subduction and rollback of the Izanagi Plate, at different times in the GXR. The GXR likely underwent flat-slab subduction during the Late Jurassic–early Cretaceous as the MOO closed in an irregular 'scissor-like' fashion (i.e. not in a progressive west to east manner). Large-scale lithospheric delamination likely led to a large pulse of magmatism and mineralisation in the GXR during the late Early Cretaceous. [ABSTRACT FROM AUTHOR]

Triassic magmatism in Northeast (NE) China was geodynamically controlled by the Mongol–Okhotsk Ocean (MOO), Palaeo-Asian Ocean (PAO), and Palaeo-Pacific Ocean (PPO) tectonic regimes. To define the mechanisms of crustal accretion and geodynamics, the magmatic processes generated by ocean closure and plate subduction must be determined. In the present study, we assembled geochronological, geochemical, Cu (Mo)-porphyry deposit, and zircon Hf isotopic data from magmatic rocks throughout NE China. Central-NE China harbours more reworking of juvenile continental crustal material than the NE China margin. The widespread Triassic felsic magmas in NE China are primarily due to the recycling of juvenile and ancient crustal components during the tectonic evolution of the PAO. During the Triassic, NE China was subjected to a syn- to post-collisional orogenic regime accompanied by scissor-like basin closure and bidirectional subduction of the eastern PAO, before transitioning to the PPO tectonic regime in the latest Triassic. Magmatism in the Erguna and the central–northern Xing'an blocks was more affected by the MOO tectonic regime. Magmatism in the central–southern Xing'an Block, the southwestern Songliao Basin, and northern Lesser Xing'an–Zhangguangcai Range was linked to the closure of the PAO. Triassic magmatic rocks along the eastern Songliao Basin are extensional and formed during the opening of the Mudanjiang Ocean. The NE margin of Eurasia was a passive continental margin in the Late Triassic. [ABSTRACT FROM AUTHOR]

In this paper, we report on LA‐ICP‐MS zircon U–Pb dates of 14 Mesozoic volcanic rocks from the central Great Xing'an Range (CGXR). These data are integrated with the temporal and spatial distribution of local magmatism‐related Mesozoic mineralization, in an effort to develop an understanding of the geodynamic evolution of the region. Periodic magmatic events in the GXR date from ~1,703 through ~145 Ma. Mesozoic volcanism in the CGXR can be subdivided into three episodes: Triassic (250–205 Ma), Early–Middle Jurassic (182–165 Ma), and Late Jurassic–Early Cretaceous (155–115 Ma). A revision of the previously defined volcanic sequence is offered using a combination of our zircon U–Pb ages and published Mesozoic geological and geophysical evidence from northeast China. We propose that (a) Early–Middle Triassic volcanism in the CGXR resulted from subduction of the Paleo‐Asian oceanic plate; (b) Late Triassic volcanism was related to subduction of the Mongol–Okhotsk oceanic plate (especially near the Erguna Block) and subsequent extension after the closure of the Paleo‐Asian Ocean; (c) Early–Middle Jurassic volcanism was mainly controlled by the southward subduction of the Mongol–Okhotsk oceanic plate; (d) Late Jurassic–initial Early Cretaceous magmatism was initiated by closure of the Mongol–Okhotsk Ocean; and (e) late Early Cretaceous volcanism was induced following the final closure of the Mongol–Okhotsk Ocean and rollback of the Paleo‐Pacific oceanic plate. [ABSTRACT FROM AUTHOR]