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In the French Armorican Massif, the Bretonian phase of the Variscan orogeny has been defined by the Late Devonian (Famennian‐Frasnian) erosion gap, and the Early Carboniferous (Tournaisian) syntectonic terrigenous deposits of the l’Huisserie formation in the Laval basin in the Central‐North Armorican Domain, ascribed to the Armorica microcontinent. This phase is coeval with vertical (epeirogenic) movements. In addition to Neo‐, and Paleo‐Proterozoic peaks, ascribed to the Cadomian and Icartian events, respectively, the detrital zircon age populations of the l’Huisserie formation reveal the existence of a 388–358 Ma magmatic event previously recognized by the ca 367–360 Ma dolerite dyke swarms exposed in the N. part of the Central‐North Armorican Domain. The isotopic (εHf) signature of these grains documents a pre‐orogenic Variscan mantle contribution for the mafic magmatism interpreted here as the indication of the south‐directed subduction of the Le Conquet‐Teplá ocean, that is, a branch of the Rheic ocean, below the Armorica microcontinent during the Bretonian phase. The intraplate opening of the Laval, Ménez‐Bélair, and Châteaulin basins was coeval with this subduction. In the Laval area, the final closure of the basin, accommodated by north‐directed folds‐and‐thrusts, took place after the Bashkirian (ca 320 Ma).

The existence of pieces of the Variscan belt in the Alpine basement has been acknowledged for a long time but the correlation of these massifs to the litho-tectonic domains established in Western Europa outside the Alpine chain is still disputed. Due to their ubiquitous character, the abundant late Variscan migmatites and granites are useless to reconstruct the Variscan architecture in the Alpine basement. Ophiolitic sutures, high- and low-grade metamorphic units, and foreland basins provide a preliminary reconstruction of the Variscan orogen exposed in the Alpine basement. The longitudinal extension of the Armorican and Saxo-Thuringian microcontinents between Laurussia and Gondwana is proposed independently of the Intra-alpine and Galatian terranes. The litho-tectonic units of the Corsica-Sardinia segment are correlated to the Moldanubian, Armorican and Saxo-Thuringian Domains. In the Alpine Helvetic and Penninic Domains, the Chamrousse ophiolites are ascribed to the Tepla-Le Conquet suture, whereas the Lepontine, and Stubach ophiolites represent the Rheic suture. The south-directed nappe stack of the South Alpine Domain is similar to the Moldanubian French Massif Central. In the Austroalpine nappe stack, the Ritting ophiolites separate Saxo-Thuringia and Armorica continental blocks. Disentangling the Variscan belt in the Alpine basement suggests a concave-to-the-East arcuate structure called here the Variscan Alpidic orocline.

The Chinese Tianshan belt is a major part of the southern Central Asian Orogenic Belt, extending westward to Kyrgyzstan and Kazakhstan. Its Paleozoic tectonic evolution, crucial for understanding the amalgamation of Central Asia, comprises two stages of subduction-collision. The first collisional stage built the Eo-Tianshan Mountains, before a Visean unconformity, in which all structures are verging north. It implied a southward subduction of the Central Tianshan Ocean beneath the Tarim active margin, that induced the Ordovician-Early Devonian Central Tianshan arc, to the south of which the South Tianshan back-arc basin opened. During the Late Devonian, the closure of this ocean led to a collision between Central Tianshan arc and the Kazakhstan-Yili-North Tianshan Block, and subsequently closure of the South Tianhan back-arc basin, producing two suture zones, namely the Central Tianshan and South Tianshan suture zones where ophiolitic melanges and HP metamorphic rocks were emplaced northward. The second stage included the Late Devonian-Carboniferous southward subduction of North Tianshan Ocean beneath the Eo-Tianshan active margin, underlined by the Yili-North Tianshan arc, leading to the collision between the Kazakhstan-Yili-NTS plate and an inferred Junggar Block at Late Carboniferous-Early Permian time. The North Tianshan Suture Zone underlines likely the last oceanic closure of Central Asia Orogenic Belt; all the oceanic domains were consumed before the Middle Permian. The amalgamated units were affected by a Permian major wrenching, dextral in the Tianshan. The correlation with the Kazakh and Kyrgyz Tianshan is clarified. The Kyrgyz South Tianshan is equivalent to the whole part of Chinese Tianshan （CTS and STS） located to the south of Narat Fault and Main Tianshan Shear Zone; the so-called Middle Tianshan thins out toward the east. The South Tianshan Suture of Kyrgyzstan correlates with the Central Tianshan Suture of Chinese Tianshan. The evolution of this southern domain remains similar from east （Gangou area） to west until the Talas-Ferghana Fault, which reflects the convergence history between the Kazakhstan and Tarim blocks.

Understanding the transition from oceanic to continental subduction is critical for reconstructing the geodynamic evolution of orogens and constraining ancient plate boundaries. The Sulu orogenic belt in eastern China was formed by Triassic deep subduction of the South China Block (SCB) beneath the North China Block (NCB). Its architecture was reformed by multi‐phase exhumation of high‐pressure (HP) to ultra‐high‐pressure (UHP) metamorphic rocks, obscuring the early syn‐convergence process. The Stenian to Tonian Wulian group—a non‐(U)HP tectonic unit—likely records the geodynamic process preceding deep continental subduction and is a key to understanding the transition from oceanic to continental subduction. Its debated tectonic affinity (SCB vs. NCB) further constrains the location of the plate boundary. We integrate structural, EBSD, and geochronological and geochemical investigations on the Wulian meta‐sediments. This group comprises a lower amphibolite‐facies unit and an upper greenschist‐facies unit. Detrital zircon U–Pb ages and Lu–Hf isotopic data indicate its affinity for SCBs. Our structural analysis reveals a Late Permian–Early Triassic (ca. 260–250 Ma) norma‐sense shearing, with top‐to‐the‐NNE kinematics accommodating the southward extrusion of the Wulian group. Deformation temperatures were 400–500°C at the lower unit and 280–400°C at the upper unit. By comparison with tectonic events of HP–UHP units, we suggest that the Wulian group was decoupled from subducting SCB during oceanic slab break‐off (ca. 260–250 Ma), while the trailing continental crust continued to subduct and experienced HP–UHP metamorphism. This model implies that the NCB–SCB plate boundary lies north of the Wulian group.

The Cenozoic Alpine, and Paleozoic Variscan and eo-Variscan collisional belts are compared in the framework of the Wilson cycle considering differences between cold and hot orogens. The W. Alps result of the opening and closure of the Liguro-Piemonte ocean, whereas the Paleozoic Eo-variscan and Variscan orogenies document multiple ocean openings and collisions in space and a polyorogenic history in time. Jurassic or Early Ordovician break-up of Pangea or Pannotia megacontinents led to the formation of passive continental margins, and the opening of Liguro-Piemonte, or Rheic, Tepla-Le Conquet, and Medio-European oceans, respectively. In Paleozoic or Mesozoic, microcontinents such as Apulia and Sesia or Armorica and Saxo-Thuringia were individualized. The oceanic convergence stage was associated with the development of arcs and back-arc basins in the Variscan belt but magmatic arcs are missing in the W. Alps, and inferred in the Eo-variscan one. Though the nappe stack is mainly developed in the subducted European or Gondwana crust in the western Alps and Eo-variscan cases, the Moldanubian nappes formed in the upper plate in the Variscan case. The Alpine and Variscan metamorphic evolutions occurred under ca. 8 °C/km and 30 °C/km gradients, respectively. During the late- to post-orogenic stages, all belts experienced “unthickening” accommodated by extensional tectonics, metamorphic retrogression, and intramontane basin opening. The importance of crustal melting, represented by migmatites, granites, and hydrothermal circulations in the Variscan and Eo-Variscan belts is the major difference with the W. Alpine one. The presence, or absence, of a previous Variscan or Cadomian continental basement might have also influenced the rheological behavior of the crust.

Continental intraplate magmatism remains a fundamental challenge in Plate Tectonics. Triassic magmatism represents a critical phase in the evolution of the Central Asian Orogenic Belt and continues to provoke debate about its tectonic setting. This study presents an integrated analysis of field, petrographic, geochronologic, geochemical, and isotopic data from two newly identified Triassic granitoids in the Bogda Range: an adakitic porphyry and a low‐Sr/Y granite porphyry. Zircon U‐Pb dating yields nearly coeval crystallization ages of 221–220 Ma and 219–217 Ma, respectively. Both granitoids are characterized by high SiO2 and K2O content, low MgO (Mg#) and Ni content, and elevated K2O/Na2O and Th/Nb ratios. They have also depleted whole‐rock Sr‐Nd and zircon Hf isotopic compositions, indicative of juvenile crustal sources. The adakitic porphyry exhibits high Sr/Y and (La/Yb)N ratios, low Rb/Sr ratios, and weak Eu anomalies, suggesting derivation from garnet‐stable mafic lower crust. In contrast, the granite porphyry displays low Sr/Y and (La/Yb)N ratios, consistent with a plagioclase‐stable source. By integrating these results with regional data, we propose that the diversity of Triassic magmatism in the Eastern Tianshan is due to the reworking of juvenile and ancient crust at different depths and temperatures, resulting in arc‐like geochemical signatures. This process was associated with transcurrent tectonics and variable mantle contributions in a continental intraplate setting.

In collision belts, the upper plate is generally less deformed than the lower one that underwent syn-metamorphic ductile shearing, and frequently late-collisional crustal melting. Concerning the Variscan orogeny, it is widely accepted that the Armorica microcontinent represented the upper plate of the collision system. In France, the Central-North-Armorican Domain belonged to this upper plate whose southern margin in the Pontivy–Coray area exposes metamorphic rocks. There, structural and metamorphic studies indicate that an early tectono-metamorphic event (M0-M1) with biotite–garnet–staurolite–kyanite assemblage, crystallized at 0.9 GPa and 500 °C, is characterized by a top-to-the NW shearing. This event was followed by an HT event (M2) at ca 800–900 °C, coeval with a domal structure. In micaschists, monazite yields an LA-ICP-MS age at 351 Ma ascribed to M2. M0-M1-M2 events developed before the Late Carboniferous pluton emplacement at ca 315 Ma (M3 event). The tectono-metamorphic succession documents that Armorica was not a rigid block but underwent a synmetamortphic ductile deformation during the Famennian–Tournaisian (360–355 Ma) collision redefined here as the late episode of the “Bretonian orogenic phase”, whereas the pre-Famennian Bretonnian episode is ascribed to oceanic subduction. These new data allow us to reassess the geodynamic evolution of this part of the Variscan orogen.

In this study, we investigated the Zicavo Metamorphic Complex (southern Corsica), which is part of the innermost Axial Zone of the Corsica-Sardinia Variscan belt. To better evaluate its geological and structural outline, a 1:5000 geological map, coupled with new structural/microstructural and petrographic data, is presented. The complex is formed by three tectonic units, from bottom to top: (i) an Orthogneiss Unit, (ii) a Leptyno-Amphibolite Unit, and (iii) a Micaschist Unit. They are separated by ductile shear zones with a top-to-the-SE sense of shear. They underwent a polyphase deformation and polymetamorphic history, with a shortening stage in the amphibolite facies, responsible for the main structures and shearing, followed by an exhumation phase.

The Montagne Noire located in the southern part of the French Massif Central represents the northern part of the South-Variscan Foreland. It is subdivided into three parts. The granite-migmatite Axial Zone dome is surrounded by non- or weakly metamorphosed Paleozoic sedimentary series. Both northern and southern flanks of the Montagne Noire dome are deformed by km-scale, south to southeast facing recumbent folds and thrusts sheets. The Raman Spectroscopy of Carbonaceous Material (RSCM) method, carried out in the low-grade metamorphic rocks of the southern flank of the Montagne Noire, yielded temperatures comprised between 400 °C near the dome, and 230 °C in the southern domain. Three Raman geothermometers were used to cover this temperature range. RSCM temperatures comply qualitatively with previous estimates based on illite crystallinity, conodont color alteration, and fluid inclusions carried out in the same area, which document a metamorphic temperature increase towards the dome. The isotherms cut across the different nappe contacts and are oriented parallel to the southern margin of the Axial Zone. This temperature distribution supports the idea that the thermal structure was acquired during the Axial Zone dome emplacement. The thermal structure acquired during the recumbent folds emplacement and burial of the sedimentary series is totally overprinted by the doming event. In addition, in a domain relatively remote from the Axial Zone dome, the RSCM measurements yielded significantly higher temperatures than illite crystallinity. This discrepancy points to a higher sensitivity of RSCM to short-lived thermal events than illite crystallinity, possibly because of more efficient kinetics of the carbonization reaction. On the other hand, high RSCM temperatures analysed far from the Axial Zone, between 300 °C and 360 °C could be explained by the presence of granitic plutons under the foreland basin. La Montagne Noire, située dans la partie sud du Massif Central français, représente la partie nord de l’avant-pays varisque. La zone est divisée en trois parties. Le dôme granite-migmatite de la zone axiale est entouré de séries sédimentaires paléozoïques pas ou faiblement métamorphisées. Les flancs nord et sud du dôme de la Montagne Noire sont déformés par des plis d’échelle kilométrique, déversés vers le sud sud-est. La méthode de spectrométrie Raman de la matière carbonée (RSCM), réalisée dans les roches de bas grade métamorphique du flanc sud de la Montagne Noire, a donné des températures comprises entre 400 °C près du dôme et 230 °C dans le domaine sud. Trois géothermomètres Raman ont été utilisés pour couvrir cette gamme de température. Ces températures RSCM sont qualitativement conformes aux estimations précédentes basées sur la cristallinité de l’illite, la couleur d’altération des conodontes et les inclusions fluides effectuées dans la même zone, qui démontrent une augmentation de la température vers le dôme. Les isothermes traversent les différents contacts de nappe et sont orientées parallèlement à la marge sud de la zone axiale. Cette distribution de température suggère que la structure thermique a été acquise lors de la mise en place du dôme de la zone axiale. La structure thermique acquise lors de la mise en place des plis couchés et de l’enfouissement des séries sédimentaires est ainsi totalement effacé par le dôme. De plus, dans un domaine relativement éloigné du dôme de la zone axiale, les mesures RSCM ont donné des températures significativement plus élevées que la cristallinité de l’illite. Cette divergence indique une sensibilité plus élevée du RSCM face à la cristallinité de l’illite aux événements thermiques de courte durée, probablement en raison d’une cinétique plus efficace de la réaction de carbonisation/graphitisation. D’autre part, de fortes températures RSCM analysées loin de la Zone Axiale, entre 300 °C et 360 °C, pourraient être expliquées par la présence de plutons granitiques sous le bassin d’avant-pays.

The overriding plate commonly accumulates less strain than the subducted plate during continental collision. Analyzing plate interactions from the perspective of the overriding plate provides important insights into orogenic dynamics. In the southeastern Tibetan Plateau, the Wuliangshan massif, as a key region of the overriding plate, records tectonic events related to the closure of both the Paleo‐Tethys and Neo‐Tethys. In this study, we present detailed structural analysis, Titanium‐in‐quartz geothermometry, and zircon U‐Pb and Hf isotopic data. These results indicate that the Wuliangshan massif experienced rapid subsidence and deposition within a short period from 260 to 250 Ma in a back‐arc tectonic setting. The polyphase deformation events were recognized in the Wuliangshan massif. The ductile syn‐metamorphism D1 event, characterized by a top‐to‐the‐SE ductile shearing under middle‐to high‐temperature conditions, represents the tectonic response to the collision between the Sibumasu block and the Indochina block occurred at ca. 250–246 Ma. The D2 deformation is expressed by E‐directed thrusts and E‐verging folds coeval with a slaty cleavage. The D3 deformation is marked by SW‐directed thrusts and SW‐verging folds. The D2 and D3 events correspond to positive flower structures related to transpression along the Chongshan‐Lancang River fault and the Ailaoshan‐Red River fault, respectively. The D2‐related Chongshan‐Lancang River fault accommodated the southward extrusion of the western part of Sundaland occurred at 32–27 Ma. The southeastward extrusion of the entire Sundaland was accommodated by the D3‐related Ailaoshan‐Red River fault at 27–23 Ma.