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[Display omitted] The Zagros orogenic belt is a major mountain system located in southwestern Iran and extending into northeastern Iraq and southeastern Turkey. It was formed as a result of the Late Paleogene-Early Neogene Arabian-Eurasian continental collision, where its proto-basin was impacted by the tectonic evolution during the Proto-Tethys and Paleo-Tethys development. The entire evolution history can be summarized through an integrated model of three Wilson cycles. This paper aims to provide an understanding of the complexities of plate motions that led to the evolution of the Zagros Fold-and-Thrust Belt, by integrating the time and space evolution of supercontinents. A comprehensive review of the Arabian plate tectonics suggests three main tectonic stages, including a period of rifting from the Late Cambrian to Carboniferous, a period of ocean closure during the Late Triassic and Jurassic, and a final collision during the Cenozoic. These tectonic evolution stages encompassed multiple episodes of basin uplifting and subsidence, marked by wide-spread fault reactivation and fold deformation. Three styles of deformation were identified and characterized, including thin-skinned, thick-skinned, and basement deformation. The closure of the Neo-Tethys Ocean resulted in compressional tectonics that reactivated dormant faults, and emplaced gypsum-salt sedimentary caprock. The genetic analysis concurrently proposes a scientific framework for the characterization of structural deformation in similar convergent plate systems globally. [ABSTRACT FROM AUTHOR]

A series of tectonic activities induced by the subduction of the Palaeo‐Asian Ocean (PAO) in the Palaeozoic have been recorded in the North China Craton (NCC). Sedimentary strata provide some precious records to reconstruct the basin evolution in the NCC. In this study, we carried out detrital zircon LA‐ICP‐MS U–Pb dating, sandstone modal analysis, bulk‐rock major, and trace elemental measurements for the Sunjiagou and Liujiagou formations in the eastern Ordos Basin to trace the material source. The results show that the sedimentary rocks were mostly sourced from active continental margins. The detrital zircon ages of the Sunjiagou and Liujiagou formations spread from >3,000 to 250 Ma with peaks of main age populations at 2,508, 1,890, 430, and 270 Ma. Based on the age comparison and the southward palaeocurrents, we consider that the source material of these sedimentary rocks comes from the northern margin of the NCC. This in turn indicates that the amalgamation of the PAO and the NCC should have finished at least by the end of the Late Permian. [ABSTRACT FROM AUTHOR]

The Northeast China Block is a major component of the Central Asian Orogenic Belt, and its tectonic evolution has attracted much research attention. Ordovician strata are important in reconstructing the tectonic evolution of the Northeast China Block. This paper presents the results of sedimentological, zircon U–Pb, and geochemical analyses of sandstones of the Luohe Formation in the Wunuer area, Northern Great Xing'an Range, Northeast China. Lithological data, sedimentary structures, and grain-size analysis indicate that the Luohe Formation was deposited in a shallow marine environment. Detrital zircon U–Pb dating yields age peaks of 463, 504, 783, 826, 973, and 1882 Ma for sandstones from the Luohe Formation. The youngest zircon grain age of 451 ± 6 Ma represents the maximum depositional age of the Luohe Formation. The peak age at 463 Ma is consistent with the timing of post-collisional magmatism and the formation of the Duobaoshan island arc, while the peak at 504 Ma is consistent with the timing of magmatic activity related to the collision between the Erguna and Xing'an blocks. The peaks at 788, 826, 973, and 1882 Ma correspond to magmatism in the Erguna block, these ages indicate that the sandstones of the Luohe Formation were derived mainly from the Erguna block. Sandstone modal compositional analysis indicates that the provenance of the Luohe Formation was mainly a magmatic arc. The geochemical compositions of the sandstones suggest that the source rocks have continental island arc signatures. Based on the depositional age, sedimentary environment, provenance, and regional geology, it is concluded that the Luohe Formation was deposited in a back-arc basin setting during the formation of the Duobaoshan island arc–basin system in response to subduction of the Paleo-Asian oceanic plate. [ABSTRACT FROM AUTHOR]

Northeast China composes the main part of the Central Asian Orogenic Belt. Traditionally, Northeast China has been considered a collage of several microcontinental blocks. However, the tectonic evolution of these blocks remains uncertain. Igneous rocks can be used to infer the magmatic histories of the blocks and thus help reconstruct their evolution. In this study, we present new zircon U–Pb and whole-rock geochemical data for Carboniferous igneous rocks from the Wunuer area, northern Great Xing'an Range, Northeast China, to constrain the Carboniferous amalgamation of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs. On the basis of zircon U–Pb dating results, we identify two main stages of magmatism, i.e., early Carboniferous (332–329 Ma) and late Carboniferous (312–310 Ma). The early Carboniferous igneous rocks include diorites and granodiorites, with the former being classified as calc-alkaline to tholeiitic and the latter as tholeiitic. Both rock types are enriched in Th and U and depleted in Nb and Ti. The rocks display slightly fractionated rare earth element (REE) patterns, with an enrichment in light REEs and a depletion in heavy (H)REEs. The geochemical characteristics of the early Carboniferous rocks indicate that they formed in a subduction-related continental-arc setting. The late Carboniferous igneous rocks include monzogranites and syenogranites, both of which are classified as high-K calc-alkaline rocks and show enrichment in Th, U, and Rb and depletion in Nb and Ti. The rocks display strongly fractionated REE patterns, with an enrichment in light REEs and a depletion in HREEs. The geochemical characteristics of the late Carboniferous rocks indicate that they formed in a syn-collisional tectonic setting. Combining the new geochronological and geochemical results and inferred tectonic settings with regional magmatic data, we propose a new three-stage model to interpret the late Paleozoic tectonic evolution of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs of Northeast China: (1) early Carboniferous (360–340 Ma) subduction of the Paleo-Asian oceanic plate beneath the united Xing'an–Erguna Massif and formation of the Wunuer oceanic basin in the Yakeshi area; (2) early to late Carboniferous (340–310 Ma) sustained subduction of the Paleo-Asian oceanic plate beneath the united Xing'an–Erguna Massif and initiation of subduction of the Wunuer oceanic basin; and (3) late Carboniferous–early Permian (310–275 Ma) syn-collisional to post-collisional tectonic transition between the united Xing'an–Erguna Massif and the Songnen–Zhangguangcai Range Massif. [ABSTRACT FROM AUTHOR]

Typical ophiolitic rock assemblages such as siliciclastic rocks, basalts and gabbros, together with the subduction-related intermediate-acidic intrusive rocks, are newly discovered in the Tongjiang-Fuyuan area of the Heilongjiang Provence, NE China. To determine the formation age and genesis of the mafic rocks (basalts and gabbros) and intermediate-acidic intrusive rocks (granodiorites) in the area, as well as their geodynamic settings, the whole-rock geochemical analysis and zircon LA-ICP-MS U-Pb dating were carried out. Zircon U-Pb results suggest that the granodiorites are 93–95 Ma and gabbro is 95 Ma, respectively. Geochemical results show that the gabbros and basalts exhibit characteristics of ocean island basalt (OIB) affinity and are typically related to having originated from mantle plumes. While the granodiorites show the nature of the island-arc magmatic rocks and may originate from the lower crust. Based on the coeval igneous rock associations and regional tectonic evolution, we conclude that the late Cretaceous magmatic rocks in the Tongjiang-Fuyuan area are the product of continuous subduction of the Palaeo-Pacific plate and reflect the subduction rollback process of the Palaeo-Pacific plate. [ABSTRACT FROM AUTHOR]

There is a controversy regarding the amalgamation of Xing'an and Songnen Blocks along the Hegenshan‐Heihe Suture (HHS) in the eastern Central Asian Orogenic Belt (CAOB). To solve this problem, we performed detailed study on the granites from the Zhangdaqi area, adjacent to the north of the HHS in the northern part of the Great Xing'an Range, NE China. Geochemically, the granites in the study area are metaluminous‐weak peraluminous and high‐K calc‐alkaline series. Trace elements of the granites show that LREEs are relatively enriched, while HREEs are relatively deficient and obvious REE fractionation. The granites are characterized by obvious negative Eu anomalies, meanwhile, they are relatively enriched in Rb, K, Th and depleted in Ba, Nb, Sr, P, Ti. All the geochemical features suggest that the granites in the Zhangdaqi area are aluminum A‐type granites. The zircon LA‐ICP‐MS U‐Pb ages of these granites are 294–298 Ma, indicating that they formed in the Early Permian. These granites also have positive εHf (t) values (8.4–14.2) and a relatively young two‐stage model age between 449 Ma and 977 Ma, implying that the magma was derived from the re‐melting of the Early Paleozoic‐Neoproterozoic juvenile crust. Combined with geochemical characteristics (Nb/Ta ratios of 9.0–22.2, and Zr/Hf ratios of 52.3–152.0), we believe that the magmatic source area is a mixture of partial melting of the lower crust and depleted mantle. A‐type granites and bimodal volcanic rocks along the Hegenshan‐Heihe Suture formed during the Late Carboniferous‐Early Permian, indicating that the HHS between Xing'an and Songnen Blocks closed in the late Early‐Carboniferous. Subsequently, the Zhangdaqi area was in a post‐orogenic extensional environment from Late Carboniferous to Early Permian and resulted in the formation of the A‐type granites. [ABSTRACT FROM AUTHOR]

The glaucophanic rocks, including the garnet‐barroisite schist (09YL10) and glaucophane aegirine‐augite schist (09YL12) from the Heilongjiang Complex exposed in the Yilan area, have been petrographically investigated, in order to contribute to the discussion on the high‐P/T metamorphism that took place in the suture zone between the Jiamusi and Songliao blocks, NE China. The mineral assemblages of peak metamorphic stage are characterized by garnet (100XCa < 26) + epidote + barroisite/katophorite + phengite (Si < 6.84 pfu) + chlorite + quartz + rutile + haematite and barroisite/katophorite + glaucophane + aegirine‐augite (Jd < 30) + epidote + phengite (Si < 6.84 pfu) + haematite ± quartz ± chlorite for the investigated samples 09YL10 and 09YL12, respectively. By applying P–T pseudosection modelling in the NCKFMASHTO system, the peak metamorphic conditions yield 550–580°C/1.1–1.3 GPa and 500–550°C/1.1–1.3 GPa, for sample 09YL10 and 09YL12, respectively, indicating the epidote‐amphibolite facies metamorphism. Furthermore, the equilibrium mineral assemblages and the estimated P–T conditions define the Alpine‐type clockwise P–T paths for the Heilongjiang glaucophanic rocks, suggesting isothermal decompression (ITD) and/or slight heating during the beginning of the exhumation process. These P–T paths significantly match to the warm subduction trajectory, indicating the tectonic regimes similar to those of young oceanic slabs subduction zones and subsequent continental orogenic belts. Taking available regional geochronological data into account, we propose that the final subduction/collision between the Jiamusi and Songliao blocks took place in the Jurassic, effected by the Palaeo‐Pacific subduction system, leading to formation of the Heilongjiang glaucophanic rocks and their high‐P/T metamorphosed pelitic country rocks. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt (CAOB) is the largest accretionary orogen in the world with considerable Phanerozoic juvenile crustal growth. The eastern segment of the CAOB is occupied by NE China and its adjacent areas, which locates in a triangle area surrounded by Siberian Craton to the northwest, North China Craton (NCC) to the south and Pacific oceanic plate to the east. Therefore, the NE China is a key area to study the geological evolution of multiple tectonic systems and overprinting, which has become a hot research topic. In the past five decades, especially the last two decades, there have been many detailed geological investigations carried out and a lot of new data reported in NE China. A progress has been achieved in tectonic evolution, however, there are still many open questions and arguments dealing with the tectonic models, correlation of tectonic units, amalgamation of different blocks and their tectonic affinity. In this study, we did a detailed review of the tectonic evolution of NE China and regional comparison and correlation of the different tectonic units in the eastern segment of CAOB. We re-subdivided NE China into two old blocks of Erguna block (EB) and Jiamusi block (JB) with Precambrian basement and three accretionary terranes of Xing'an accretionary terrane (XAT), Songliao accretionary terrane (SAT) and Zhangguangcai accretionary terrane (ZGCAT), which are separated from each other by the Xinlin-Xiguitu suture (XXS), Hegenshan-Heihe suture (HHS), Longfengshan suture (LFS) and Mudanjiang-Yilan suture (MYS), respectively. The ZGCAT is dominantly composed of early Paleozoic magmatic arc materials and minor late Paleozoic igneous rocks with an old Yichun mini-block, while the SAT consists dominantly of the late Paleozoic magmatic rocks with two small old blocks of the Xilinhot and Longjiang mini-blocks. According to the tectonic correlation and comparation of different tectonic units, we established a new orocline tectonic model for the eastern CAOB: 1) the XAT and ZGCAT accreted to the southern (present position) margin of Ereendavaa-Erguna-Mamyn block (EEMB) and Bureya-Jiamusi-Khanka block (BJKB) with the closure of Xinlin-Xiguitu-Heilongjiang ocean during the early Paleozoic; 2) Subsequently, the SAT accreted to the southern (present position) margin of integrated XAT-ZGCAT terrane with the closure of Hegenshan-Nenjiang-Longfengshan ocean during the late Paleozoic. These initially W-E linear shaped accretionary orogenic belts were ultimately bent southward through Paleozoic time and constituted a huge Paleozoic orocline, NE China Orocline, which collided with NCC by a scissor-like style closure of Paleo-Asian Ocean (PAO) from west to east along the Solonker-Xar Moron-Changchun-Yanji suture (SXCYS) during the late Permian-middle Triassic. The NE China Orocline, together with Tuva-Mongol Orocline and Kazakhstan Orocline in the western CAOB, constituted a huge multiple orocline tectonic system in the CAOB during the Paleozoic era. Our study will contribute to the understanding on tectonic evolutions of CAOB and the NE Asian, and suggests that the orocline should be a common tectonic model for accretionary orogeny. • NE China consists of two Precambrian blocks and three Paleozoic accreted terranes. • A new orocline tectonic model is established for first time in NE China. • Blocks in NE China had been integrated in later Early Carboniferous. [ABSTRACT FROM AUTHOR]