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The nature, extension, and evolution of the Meso-Tethys still remain unclear to researchers, and this has thereby hindered in-depth study of the Tethys tectonic domain. In this paper, we review the geology of the Tethys tectonic domain and suggest that the Meso-Tethys is a massive tectonic zone divided into three segments. The central segment includes the Bangong-Nujiang Suture Zone on the Tibetan Plateau and the Shyok Suture Zone in the South Pamir Mountains. This segment has been well studied and is the key link that fully records the birth, evolution, and demise of the Meso-Tethys Ocean from the Permian to Cretaceous, as well as the subsequent continental collision and crustal uplift. The western segment includes the Sanandaj-Sirjan Suture Zone and the Izmir-Ankara-Erzincan Suture Zone in the Middle East. Due to limited research on the western segment, our understanding of it is mainly derived from records of the Jurassic forearc extension,development of arc, and subsequent arc-continent collision. The eastern segment includes the Shan Boundary in Southeast Asia. It has received widespread attention in recent years, and it contains complete records of the Jurassic subduction of the Meso-Tethys Ocean. Based on the latest comprehensive data, we propose that the evolution of the Meso-Tethys Ocean can be divided into four stages: (1) the Early Permian rifting and opening stage; (2) the Middle Permian-Triassic seafoor spreading stage; (3) the Late Triassic-Jurassic convergence stage; and (4) the Late Jurassic-Early Cretaceous diachronous closure from east to west in the central segment and transition from the Meso-Tethys evolution to the Neo-Tethys evolution in both the eastern and western segments. The Meso-Tethys Ocean underwent complex evolution for at least ∼160 Myrs. It has an east-west length of over 8000 km and a maximum north-south width of close to 5000 km during the Late Triassic, which basically reached the scale of the current Indian Ocean. It was an important ocean basin that coexisted with the Paleo- and Neo-Tethys oceans, a key intermediate link in the evolution of the Tethys, and one of the major contributors to the continuous disintegration of Gondwana and the accretion of the Eurasian continent. Its complex evolution process and multiple periods of accretion resulted in the formation of complex geological records and the wide scale of the Meso-Tethys (e.g., the Bangong-Nujiang Suture Zone), making this area a rare natural laboratory for in-depth study of orogenesis, which is of great significance for studying tectonic processes on the global scale from seafloor geology to continental accretion and mineralization. [ABSTRACT FROM AUTHOR]

The Proterozoic geological records in eastern South China preserve a history linked to the Columbia and Rodinia supercontinent cycles and provide key constraints in understanding the geodynamic evolution of East Asia. However, it is uncertain if SW Hainan, Yangtze and Cathaysia were located in the interior or periphery of the Precambrian supercontinents, how they were connected prior to the formation of a united South China, whether the early Neoproterozoic Proto-Huanan subduction was long- or short-lived, and how and when Yangtze and Cathaysia were assembled along the Jiangnan Orogen. This paper provides an overview of key geological observations for the eastern Yangtze and Cathaysia with respect to Proterozoic tectonics. Our synthesis shows that the SW Hainan in the Mesoproterozoic (ca. 1.45 Ga) developed in a non-orogenic rift setting in the interior of Columbia. SW Hainan, together with SW Yangtze, drifted to the margin of Rodinia by ∼1.05 Ga. Furthermore, SW Hainan might have been part of the Mesoproterozoic Albany Fraser Orogen at ca. 1.30–1.05 Ga. Cathaysia and eastern Yangtze display distinct geological signatures in the early Neoproterozoic and Cathaysia remain separated from Yangtze until at least ca. 1.0 Ga. The ca. 1.0–0.9 Ga felsic igneous rocks in Cathaysia to the east of the Jiangshan-Shaoxing suture zone are mostly characterized by negative ε Hf (t) values, and distinct from those in the coeval Shuangxiwu arc to the west of the Jiangshan-Shaoxing suture zone, which have positive ε Hf (t) values. Igneous rocks dated at ca. 870–830 Ma (mainly ca. 850–830 Ma) are extensive in the Huaiyu and Jiangnan Orogen but poorly developed in Cathaysia. Neoproterozoic sedimentary rocks of Cathaysia contain abundant ca. 980 Ma detrital grains but only minor ca. 860–830 Ma grains. In contrast, in the Jiangnan and Huaiyu, the sedimentary rocks contain a dominant ca. 860–830 Ma detrital zircon age-peak but ca. 980 Ma grains are scare. Rift-related bi-model igneous rocks, ranging in age from ca. 810 Ma to ca. 750 Ma, represented by the Banxi, Likou and Mamianshan groups and their equivalents, are extensively developed in Cathaysia and Huaiyu, and the Jiangnan Orogen. These rift-related successions are separated from the Cangshuipu and Luojiamen conglomerates across an angular unconformity, which are in turn unconformable on the Lengjiaxi and Xikou groups. It is herein proposed that an early Neoproterozoic (ca. 1.0–0.9 Ga) accretionary orogen developed within the Cathaysia and lay along strike from the synchronous Eastern Ghats Orogen of India. A long-lived Neoproterozoic (ca. 0.97–0.83 Ga) Proto-Huanan arc-trench system resulted in the development of the ca. 0.98–0.88 Ga Shuangxiwu intra-oceanic arc, ca. 0.87–0.83 Huaiyu continental arc and ca. 0.87–0.83 Jiangnan intra-continental back- arc basin in response to the ongoing westward-subduction beneath the eastern Yangtze. At ca. 0.87 Ga, the arc-trench system switched from an intra-oceanic to a continental Andean margin setting. Such a system might be compatible to the NW India South Delhi Orogen at the periphery of Rodinia. Our synthesis shows that the united proto-South China was finally created by the ca. 830–810 Ma assemblage of the Yangtze with Cathaysia along the Jiangnan Orogen and was followed by the post-orogenic rifting due to the breakup of Rodinia. [ABSTRACT FROM AUTHOR]

The timing, kinematics, and geodynamic evolution of the India-Asia continental collision are crucial to understanding the geological and geomorphological evolution of the Himalayan-Tibetan orogen. However, the debate over how and when the collision occurred persists due to disputes concerning the reliability of paleomagnetic data obtained on both sides of the suture zone. This paper presents a comprehensive analysis and evaluation of paleomagnetic studies to address this controversial issue. The study focuses on well-preserved Cretaceous-Paleocene rocks from the Lhasa and Tethyan Himalaya (TH) terranes over the past two decades. We conclude that: (1) the paleomagnetic data of the Linzizong Group of the Lhasa Terrane and the Zongpu Formation of the TH are in their primary origin and can be used for tectonic reconstruction; (2) the Tethys Himalaya Basin (THB) was generated due to the rifting of the TH from Greater India before the Late Cretaceous; (3) the southern margin of Asia was aligned in the NW-SE direction before the India-Asia collision. The study suggests a quasi-synchronous multi-stage collision where the TH collided with the Trans-Tethyan subduction system in Late Cretaceous-Early Paleocene times (∼65 Ma), followed by collision with Asia at 56–59 Ma. Finally, the India Craton collided with the TH, resulting in the synchronous closure of the THB at approximately 40 Ma. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt (CAOB) was generated through multiple collisional and accretionary events in the Paleo-Asian Ocean, a major global ocean that existed from the late Neoproterozoic into the late Paleozoic. Nevertheless, the question of when the Paleo-Asian Ocean finally closed has notoriously been enigmatic, especially due to the absence of large-scale investigations. The South Tianshan-Solonker Suture, is the largest and southernmost suture within the CAOB, and records the ultimate collision between the Tarim-North China cratons with the Siberia craton, and is commonly interpreted as marking the eventual closure of the Paleo-Asian Ocean. In this paper, we synthesize and evaluate relevant Chinese papers on the area, which are not readily available to an international audience, and extend this across the full length of the suture zone. Based on this review, we can divide the suture zone into four distinct segments, which are, from west to east: the South Tianshan Belt, the Beishan Belt, the Solonker Belt and the Yanji Belt. This enables us to provide a more systematic understanding of the nature and development of the South Tianshan-Solonker suture. Geochronological data from Paleozoic cover rocks and high-pressure metamorphic rocks show that during the late Carboniferous, the western section of the Paleo-Asian Ocean closed when the Tarim Craton moved northward to collide with the Kazakhstan-Yili Block, thus marking the initial development of the South Tianshan Belt. The Beishan Belt to the east formed when the Dunhuang-Alxa blocks were transported northward to collide with the Tuva-Mongolia Block, with the youngest zircon U Pb data from ophiolites indicating that closure of the local Beishan Ocean was in the early-middle Permian, although its final closure may not have been until the early late Permian along the northern margin of the Alxa Block, thus making it slightly younger than the South Tianshan Belt. Further to the east, the available petrographic, geochronological and paleontological data from the Solonker Belt indicate that this belt was formed in the middle-late Permian, during which time bi-directional subduction occurred and the North China and Siberia cratons were amalgamated during an 'Appalachian-type' orogeny. Furthermore, we observe that a transition in polarity from northward to bi-directional subduction occurred along the boundary between the Beishan and Solonker belts, which may be related to the East Gobi Transform Fault. In contrast, under the influence of the westward subduction of the Paleo-Pacific Ocean, the Jiamusi-Khanka Block moved southwestward along the Yilan-Yitong Fault in the middle-late Triassic (230–220 Ma) to amalgamate with the North China Craton. The formation of the South Tianshan-Solonker Suture can be characterized by four distinct west-to-east accretion/collision events that lasted from the late Carboniferous to the late Permian. The South Tianshan Belt, the Beishan Belt and the Solonker Belt therefore demarcate, respectively, the amalgamation between the Tarim Craton and the Kazakhstan-Yili Block, the Dunhuang-Alxa Block and the Tuva-Mongolia Block, and the North China Craton with the Siberia Craton, representing the final closure of the Paleo-Asian Ocean. During the middle-late Triassic, the Yanji Belt in the far east was influenced by the Paleo-Pacific tectonic domain as a result of amalgamation between the Jiamusi-Khanka Block and the North China Craton. • South Tianshan-Solonker Suture marks the final collision between Tarim-North China and Siberian cratons. • The Suture includes four segments, and closed form Late Carboniferous to Middle Triassic from west to east, respectively. • The Yanji belt was influenced by the Paleo-Pacific tectonic domain during the Middle Triassic. [ABSTRACT FROM AUTHOR]

Northeast (NE) China is located in the eastern Central Asian Orogenic Belt (CAOB) and evolved from the amalgamation of several microcontinental blocks, which, from west to east, include the Erguna, Xing'an, Songliao, and Jiamusi-Khanka blocks. Since the Paleozoic, NE China has undergone multiple stages of subduction–accretion and tectonic destruction under the tectonic domains of the Paleo-Asian Ocean, Panthalassa, and the Paleo-Pacific Ocean. This complexity has resulted in uncertainty surrounding the amalgamation processes of the various microcontinents. Fortunately, several suture zones in NE China, including the Toudaoqiao–Xinlin Suture, the Hegenshan–Heihe Suture, the Solonker–Xar Moron–Changchun Suture, and the Jilin–Heilongjiang High-pressure Belt contain information that provides key constraints on the tectonic evolution of NE China. This paper reviews the spatial distribution, composition, and formation ages of these suture zones based on published geological records. Our temporal and spatial analyses of these suture zones enable the evolution of NE China to be assigned to those three tectonic domains: (1) In the earliest of these, the Paleo-Asian Ocean tectonic domain (650–250 Ma), the Erguna Block amalgamated with the Xing'an Block along the Toudaoqiao–Xinlin Suture during the Late Cambrian (ca. 500 Ma); the Erguna–Xing'an Block then collided with the Songliao Block along the Hegenshan–Heihe Suture during the Late Carboniferous (ca. 300 Ma), whilst the combined Erguna–Xing'an–Songliao Block amalgamated with the North China Craton along the Solonker–Xar Moron–Changchun Suture at the End-Permian (ca. 250 Ma). (2) in the Panthalassa tectonic domain (315–230 Ma), the subduction of Panthalassa (or locally, the Mongol-Okhotsk Ocean) was initiated in the eastern Jiamusi-Khanka Block during the Late Carboniferous (ca. 315 Ma), resulting in back-arc extension in the western Jiamusi-Khanka Block, which evolved into the Heilongjiang Ocean separating the Jiamusi-Khanka and Songliao blocks during the Late Permian to Late Triassic (260–230 Ma). (3) in the Paleo-Pacific Ocean tectonic domain (230–130 Ma), the first stage of westward subduction of the Paleo-Pacific oceanic plate occurred during the Late Triassic (ca. 230 Ma), causing the Jiamusi-Khanka Block to amalgamate with the North China Craton during the Late Triassic (ca. 230 Ma) and subsequently with the Songliao Block during the Late Triassic to Early Jurassic (210–180 Ma), forming the Jilin–Heilongjiang High-pressure Belt, whereas the second stage of subduction induced the emplacement of the Nadanhada Terrane during the Early Cretaceous (ca. 130 Ma). This represented the final assembly of NE China in the eastern CAOB. • NE China can be divided into three tectonic domains of the Paleo-Asian Ocean, the Panthalassa, and the Paleo-Pacific Ocean. • The assembly of NE China was accomplished through the generation of five suture zones, which formed from ∼500 Ma to ∼130 Ma. • NE China recorded multiple stages of activity of the Paleo-Asian, Panthalassa (Mongol-Okhotsk), and the Paleo-Pacific oceans. [ABSTRACT FROM AUTHOR]

Subduction and closure of the Proto-Tethys and Palaeo-Tethys oceans were important events in the assembly of Eurasia, and created the Central China Orogenic Belt (CCOB). This paper presents a new tectonic model for the CCOB in which we propose that elongate Precambrian basement blocks within the CCOB were originally part of a single ribbon continent, here named K-Qubed after the K unlun- Q aidam- Q ilian- Q inling regions. K-Qubed separated from the South China Block in the Neoproterozoic. Dextral-oblique subduction of the Proto-Tethys Ocean took place southwards (present co-ordinates) under K-Qubed in latest Precambrian - Cambrian times (ca. 550–500 Ma). Subduction-accretion complexes were generated alongside the basement, while arc magmatism overprinted both basement and accretionary crust. Initial collision of the northern side of the ribbon continent and the North China and Tarim blocks occurred at ca. 500 Ma. High-pressure and ultrahigh-pressure metamorphism resulted by ca. 490 Ma, in the North Qilian, South Altun/North Qaidam and North Qinling regions. Collision triggered a flip in subduction polarity, and caused a subduction-accretion complex and magmatic arc to build out southwards from K-Qubed, as Palaeo-Tethys was consumed northwards in the Ordovician. Magmatic timings were similar between different tectonic units; twin peaks in magmatism at ca. 500–490 Ma and ca. 440–430 Ma occurred in several terranes. Oblique subduction caused strain partitioning, in turn causing slivering and across-strike repetition of basement and accretionary crust. Tectonic units in the Qilian Shan and Kunlun can be partly correlated with equivalents in the Qinling Orogen. We suggest a match between the North Qilian Orogenic Belt and the Erlangping Unit, between the Central Qilian Block and the North Qinling Belt, between the South Qilian Accretionary Belt and the Shangdan Suture Zone. Basement terranes of the Qaidam region and the East Kunlun Orogen have no obvious lateral equivalents in the Qinling, and are truncated at the eastern margins by the West Qinling Belt. There are similar ages for peak metamorphism at ca. 440–420 Ma in an eclogite belt in the North Qaidam Ultra High-pressure Metamorphic Belt (NQUB) and eclogite localities in the East Kunlun Orogen. We interpret this metamorphism to be result of slab break-off beneath the K-Qubed continent, with metamorphic rocks repeated across-strike by dextral shear. The component of Precambrian crust in the Kunlun diminishes westwards into the West Kunlun, where Early Palaeozoic accretion of crust was more continuous. A magmatic gap throughout the CCOB between ca. 370 and ca. 290 Ma was possibly related to extremely oblique and/or slow plate convergence, or represents a time through which subduction stopped. Renewed northwards subduction of the Palaeo-Tethyan Ocean took place under the south side of the Kunlun and Qinling in the Permian, completed by Triassic collisions of the Qiangtang and South China blocks with the southern side of the CCOB. This model for the CCOB is an alternative to collisional and accretionary end members for orogeny, whereby oblique subduction and collision of a ribbon continent produces interleaving of basement and more juvenile terranes. Closure of Proto-Tethys did not involve multiple, separate and synchronous subduction zones, or repetition of a subduction zone by oroclinal bending, as previously proposed. [ABSTRACT FROM AUTHOR]

NW Iberia includes a rather complete section of a Variscan suture, where different terranes with continental or oceanic affinities appear with clear structural relationships. Three groups of terranes, namely Upper, Ophiolitic and Basal units and a frontal tectonic mélange appear in Galicia, in Cabo Ortegal, Órdenes and Malpica-Tui complexes. They constitute a huge allochthonous pile thrust over the Iberian parautochthonous and autochthonous domains, which represent the section of the Gondwanan margin that escaped continental subduction during the Variscan cycle. Considering the allochthonous character of the nappe pile and the strong deformation associated to the Variscan collision, there are problems to identify the original tectonic setting of the terranes and thence, it is difficult to reconstruct the paleogeographic context during the Variscan and pre-Variscan times in detail. Key features to perform any model for the Variscan convergence should consider the existence of two different high-P metamorphic events (dated at c. 400 and 370 Ma, respectively), separated in time for the generation of mafic-ultramafic sequences at c. 395 Ma which constitute the most common ophiolites described in the Variscan suture. Some dynamic models developed in NW Iberia have important problems to explain the observed tectonothermal evolution, especially the older high-P metamorphic event and the exhumation of deeply subducted transitional-type sections. On the other hand, the recently discovered participation of an older continental crust in the generation of different protoliths of the Middle Devonian ophiolites, makes difficult the interpretation of these ophiolites in relation to open wide oceanic domains. This paper describes the distribution, structure, lithologies, geochronology and chemical composition of the terranes involved in the Variscan suture of NW Spain. The scope of this description ranges from detailed regional aspects to the discussion of the development of the Variscan Orogen in the context of the assembly of Pangea. A two-stage collisional model affecting a wide Gondwanan platform may explain most of the evidences in NW Iberia. The generation of a long pull-apart basin probably occurred after the first collision, where the Devonian ophiolites were formed. These ophiolites have been in general described in the context of the Rheic Ocean, but according to the new existing data they do not seem related to this ocean, but rather they were formed after its closure. [ABSTRACT FROM AUTHOR]

This paper reviews the spatial-temporal distribution, geological and geochemical features, and geophysical context of diverse types of Cenozoic ore deposits formed during India-Eurasia continental collision in Tibet, in order to shed new light on their genesis and their control by mantle lithosphere. The parental magmas for porphyry-skarn Cu (± Mo ± Au) deposits were derived from metal-rich pre-Cenozoic juvenile crust, and the high magma oxidation state was controlled by involved mantle-derived basic magmas and thickened crust condition; magma emplacement was controlled by structures related both to tears in the subducting continental slab to deep and to mantle-crust decoupling parts at depth. Orogenic Au deposits mostly formed intermittently from hydrothermal fluids formed by devolatilization of earlier-fertilized mantle lithosphere that was triggered by asthenosphere upwelling; they were largely controlled by lithosphere-scale shear systems that reactivated earlier-formed suture zones. Giant MVT Zn Pb deposits, hosted by ancient oil reservoirs, formed during salt diapirism and infiltration of metal-rich basinal brines related to crustal-scale channel flow. The diverse range of ore deposits was derived predominantly through release of metal and fluid components, introduced into the crust and mantle lithosphere that occurred in the earlier oceanic subduction during anomalous lithosphere-scale deformation. The metallogenic history of collisional orogens contrasts with those of accretionary orogens. • Tibetan mineralization system provides an important global insight into metallogenesis during continental collision. • Lithosphere architecture and fertility formed by oceanic subduction control diverse ore deposits in collision setting. • Diverse types of Tibetan ore deposits have different genesis to those from oceanic subduction settings. • Tibetan ore deposits formed in various geodynamic settings of thrusting, shearing, rotation, and rifting. [ABSTRACT FROM AUTHOR]

Basalts are ubiquitous, mantle-derived mafic rocks found within all tectonic settings. Studying the chemical composition of basalts has proven to be an effective way to understand tectonics-related mantle processes for more recent periods of Earth history when other geological and tectonic records are still well preserved. However, using basalt geochemistry to decipher ancient tectonic environments and mantle processes on Earth remains a significant challenge; interpretations are often non-unique, and weathering, erosion, and orogenic processes can modify the chemical composition of basalts, and eliminate or obscure other complementary geotectonic records. This is most apparent in the oceanic realm, where subduction-related processes have erased much of the geological record for times older than ∼200 Ma, only leaving small and rare dismembered blocks of oceanic lithosphere as ophiolite mélanges along tectonic sutures. As a result, workers must rely heavily on analyzing the chemical composition of preserved basalts to identify the tectonic settings of their original melt extraction from the mantle using various tectonic discrimination diagrams from the literature (e.g., Pearce and Cann, 1973). In this paper, we demonstrate that such widely used classic discrimination diagram approaches often suffer from the intrinsic shortfall of large ambiguity. Instead, we apply here a big-data approach to characterize basalts generated in some typical tectonic settings. We start with a bespoke data correction and machine learning workflow. Our results show that mid-ocean ridge basalts, ocean island basalts, continental flood basalts, arc basalts (from both the oceanic and continental realm), and oceanic flood basalts are statistically chemically different, thus presenting a novel and unique chemical 'fingerprinting' approach to more accurately discriminate basalts. The method successfully predicts the tectonic settings of basalt emplacement at a prediction accuracy of >96%. [ABSTRACT FROM AUTHOR]

Reconstructing the evolution of the Bangong-Nujiang Tethyan Ocean (BNTO) plays an indispensable role in understanding the linkage between Gondwana dispersion and Tibetan Plateau accretion. The existence of the BNTO is inferred from presence of dismembered ophiolite bodies along the Bangong-Nujiang suture zone, which separates Lhasa from Qiangtang. In this paper, we present a detailed synthesis of ophiolite, metamorphism, magmatism, lithostratigraphy and tectonism from the western segment (Gerze area) of the Lhasa-Qiangtang collision zone in order to reconstruct the Wilson cycle of the BNTO. Our results suggest that the BNTO initially opened in the Late Permian (~260 Ma), as indicated by the earliest record of oceanic crust. Regionally, strong evidence supports a northward subduction of the BNTO beneath Qiangtang, likely initiating in the Early Jurassic (~195 Ma). As suggested by detrital zircon age spectra from Mesozoic arc-sourced strata, northward oceanic subduction generated three episodes of arc magmatism, i.e., ~186–170 Ma, ~169–146 Ma and ~129–100 Ma along the southern Qiangtang margin, in which the Early Jurassic magmatism is only sporadically preserved in modern outcrops (Amdo area). Meanwhile, the recognition of an incomplete arc-trench system on the northern Lhasa margin supports a southward subduction beneath Lhasa as well. Our new provenance data from Lower Cretaceous strata on the northern Lhasa margin, together with available multi-disciplinary constraints, suggest that final closure of the BNTO did not occur until the latest Jurassic-Early Cretaceous (~150–130 Ma). Therefore, the Wilson cycle of the BNTO is hereby reconstructed, providing significant insights into the amalgamation of the Tibetan Plateau. • The Bangong-Nujiang Tethyan Ocean initially opened in the Late Permian (~260 Ma). • Northward oceanic subduction under Qiangtang initiated in the Early Jurassic (~195 Ma). • The Lhasa-Qiangtang collision occurred during Late Jurassic-Early Cretaceous (~150–130 Ma). • Early Jurassic (~185–170) magmatism was once widespread along southern Qiangtang margin. [ABSTRACT FROM AUTHOR]