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We present zircon U–Pb and Hf isotopic and whole‐rock geochemical data for late Paleozoic igneous rocks in the central Great Xing'an Range, northeast China, to constrain the late Paleozoic amalgamation history of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs. Based on zircon U–Pb dating, we ascertain three main stages of magmatic events: Late Devonian (381–364 Ma), early Carboniferous (360–341 Ma), and late early Carboniferous–early Permian (328–271 Ma). Late Devonian rhyolites originated from partial melting of Meso‐proterozoic accreted lower crust. The crust‐derived rhyolites and coeval mantle‐derived basalts constitute a bimodal volcanic association in the west. Early Carboniferous igneous rocks include syenogranites, monzogranites, gabbro diorites, and gabbros. The granitoids are derived from partial melting of Meso‐proterozoic accreted lower crust. The gabbros and gabbro diorites show the spatial variation in zircon εHf(t) values (−0.53 to +0.84 in the east and +12.3 to +13.5 in the west), which imply that they were mainly derived from metasomatized mantle wedge and asthenosphere mantle, respectively. These characteristics indicate that northwest‐towards high‐angle subduction of the Paleo‐Asian Ocean plate beneath the united Xing'an–Erguna Massif induced arc magmatism in the east and back‐arc magmatism (similar to back‐arc rift) in the west during the Late Devonian to early Carboniferous. Late early Carboniferous–early Permian sub‐alkaline and alkaline igneous rocks are characterized by multiple sources, such as the depleted mantle, juvenile lower crust, and thickening lower crust. Their temporal variations in geochemical characteristics imply that the central Great Xing'an Range was situated under a transitional setting from syn‐collisional to post‐collisional during the late early Carboniferous to early Permian. Using the combined insight from lithofacies palaeogeography and regional magmatisms, we suggest amalgamation of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs occurred during the late early Carboniferous to late Carboniferous. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We present new zircon U–Pb–Hf and whole-rock geochemical data for volcanic rocks along the eastern margin of the Xing'an Massif of NE China in order to further our understanding of the history of subduction towards the SE and the spatial extent of the Mongol–Okhotsk tectonic regime. Zircon U–Pb dating indicates that the Triassic volcanism in the Xing'an Massif occurred in two stages during the Middle (ca. 242 Ma) and Late (ca. 223–228 Ma) Triassic. Middle Triassic basaltic andesites in the Heihe area have an affinity to arc-type volcanic rocks. The zircon ε Hf (t) values (+ 8.5 to + 12.7) suggest that the primary magma was generated by the partial melting of a relatively depleted mantle wedge that had been metasomatized by subduction-related fluids. The Late Triassic andesites in the Handaqi area exhibit geochemical affinities to high-Mg adakitic andesites. Their zircon ε Hf (t) values (+ 11.5 to + 14.5) and T DM2 ages (313–484 Ma) indicate that their primary magma was derived from the partial melting of a young subducted oceanic crust, followed by interaction with melts derived from mantle peridotite. The Late Triassic basaltic andesites, andesites, and dacites in the Zhalantun–Moguqi area have features similar to those of igneous rocks formed in subduction zones. Their zircon ε Hf (t) values (+ 8.4 to + 15.4) and T DM1 ages (260–542 Ma) indicate that their primary magma was derived from the partial melting of a depleted mantle wedge that had been metasomatized by subduction-related fluids. These data suggest that the Triassic volcanic rocks of the Xing'an Massif formed in an active continental margin setting associated with the southward subduction of the Mongol–Okhotsk oceanic plate towards the SE. We conclude that the Mongol–Okhotsk tectonic regime extended at least as far as the eastern margin of the Xing'an Massif, and that the tectonism spanned the period from the late Permian to early Early-Cretaceous. [ABSTRACT FROM AUTHOR]

Here we present new U–Pb and Hf isotopic data for detrital zircons obtained from six samples of late Palaeozoic units from central Jilin Province, Northeast China, and use these data and sedimentary formations to constrain the late Palaeozoic tectonic evolution of the eastern segment of the southern margin of the Central Asian Orogenic Belt. The majority of the detrital zircons from the six samples are euhedral–subhedral and exhibit oscillatory zoning, indicating a magmatic origin. Zircons from sandstones in the Devonian Wangjiajie and Xiaosuihe formations yield seven main age populations (399, 440, 921, 1648, 1864, 1911, and 2066 Ma) and two minor age populations (384 and 432 Ma), respectively. Zircons from a quartz sandstone in the Carboniferous Luquantun Formation yield four age populations (~332, 363, 402, and 428 Ma), and zircons from quartz sandstones of the Permian Shoushangou, Fanjiatun, and Yangjiagou formations yield age populations of 265, 369, 463, 503, and 963 Ma; 264, 310, 337, 486, and 529 Ma; and 262, 282, 312, 338, 380, 465, and 492 Ma, respectively. These data, together with the ages of magmatic zircons from interbedded volcanics and biostratigraphic evidence, as well as analysis of formations, give rise to the following conclusions. (1) The Wangjiajie and Xiaosuihe formations were deposited in an extensional environment during Middle and Middle–Late Devonian time, respectively. The former was sourced mainly from ancient continental material of the North China Craton with minor contributions from newly accreted crust, while the latter was sourced mainly from newly accreted crust. (2) The Luquantun Formation formed in an extensional environment during early–late Carboniferous time from material sourced mainly from newly accreted crust. (3) The Shoushangou, Fanjiatun, and Yangjiagou formations formed during a period of rapid uplift in the late Permian, from material sourced mainly from newly accreted crust. [ABSTRACT FROM AUTHOR]

This paper presents new results on zircon U–Pb dating, Hf isotope analyses, and trace and major element analyses of Late Devonian and early Carboniferous metavolcanic rocks and early Carboniferous alkaline granites of central Jilin Province, NE China, and uses these data to constrain the late Paleozoic tectonic evolution of the southern margin of the Central Asian Orogenic Belt (CAOB). Zircon U–Pb ages, determined using laser ablation–inductively coupled plasma–mass spectrometry, indicate that Late Devonian Jifanggou Group metarhyolites formed at ∼360 Ma, whereas the early Carboniferous Panling Formation metabasaltic andesites and metarhyolites and the Silengshan alkaline granite formed at ∼340 Ma. The Late Devonian metarhyolites, which exhibit zircon ε Hf ( t ) values of +2.77 to +8.94 and corresponding two-stage model ages ( T DM2 ) ages of 969–1525 Ma, are geochemically similar to I–A-type granites, which is indicative of formation from a primary magma generated by partial melting of juvenile lower crustal material in an extensional environment. The early Carboniferous metabasaltic andesites and metarhyolites are geochemically bimodal, with SiO 2 concentrations of 52.1–61.4 and 72.8–75.1 wt.%, respectively. The former are enriched in Ba, Sr, Th, and U, and are depleted in K, Rb, Nb, Ta, and Ti, whereas the latter are enriched in light rare earth elements (LREEs) and large ion lithophile elements (LILEs; e.g., Rb, K, Th and U), and are depleted in heavy REEs (HREEs), high field strength elements (HFSEs; e.g., Nb, Ta, Ti, and P), and Sr. Zircons from the metabasaltic andesite and metarhyolite units have ε Hf ( t ) values of +9.80 to +12.8 and +11.0 to +13.1, respectively, and corresponding single-stage model ages ( T DM1 ) and two-stage model ages ( T DM2 ) of 468–606 and 584–776 Ma, respectively. Silengshan alkaline granite samples contain minor amounts of riebeckite, are relatively LREEs and LILEs enriched and HREEs and HFSEs depleted, and have markedly negative Eu anomalies, features that are typical of A-type granites. These granite samples have zircons with ε Hf ( t ) values of +8.04 to +13.4 and corresponding T DM2 ages of 549–1037 Ma. These data suggest that the primary magma that formed the early Carboniferous metabasaltic andesites was derived from partial melting of depleted lithospheric mantle material that had been modified by subduction-related fluids, whereas the primary magmas for the coeval metarhyolites and the Silengshan alkaline granite were derived from partial melting of newly accreted crust. These early Carboniferous igneous rocks formed in an extensional setting within the eastern segment of the southern CAOB. [ABSTRACT FROM AUTHOR]