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It was recognized that two magmatic belts in the Lhasa‐Tengchong terrane formed due to the Mesozoic‐Cenozoic Tethyan evolution. Still, their spatiotemporal variations of magmatic flare‐ups/lulls are rarely discussed. Here we use the new U‐Pb and Lu‐Hf isotopic data of captured zircons and a comprehensive data set to show that the flare‐up of northern magmatic belt has peak ages of 110 Ma in central and northern Lhasa and 120 Ma in eastern Tengchong, possibly related to the tectonic transition from Meso‐ and Neo‐Tethyan double subduction to Neo‐Tethyan single subduction. For the southern magmatic belt, the flare‐ups at 100–85 Ma and 65–45 Ma in eastern southern Lhasa indicate obvious juvenile crustal growth, while flare‐ups at 75–45 Ma in western southern Lhasa and Tengchong record ancient crustal reworking. Such flare‐up variations in the southern magmatic belt possibly resulted from asynchronous changes in the Neo‐Tethyan slab dip. Plain Language Summary The Tethyan slab subduction and following collision of India and Asia produced two magmatic belts in the Lhasa‐Tengchong terrane. How did the magmatic flare‐ups or high‐flux episodes and sources spatiotemporally vary? We combine the new U‐Pb and Lu‐Hf isotopic data of captured zircons (xenocrystic zircons caught by volcanics from country rocks) and a comprehensive data set to show that the peak ages of early Cretaceous flare‐up of the northern magmatic belt are ca.10 Ma younger in central and northern Lhasa than in eastern Tengchong, possibly related to the diachronous closure of the Meso‐Tethys and flat subduction of the Neo‐Tethys. The southern magmatic belt in Tengchong and western southern Lhasa exhibit 75–45 Ma flare‐ups featured by the reworking of ancient crust, different from the eastern southern Lhasa with the flare‐ups at 100–85 Ma and 65–45 Ma which are dominated by the juvenile crustal growth. Such flare‐up variations may be related to changes of the Neo‐Tethyan slab dip. Key Points The Neo‐Tethyan arc has asynchronous magmatic flare‐ups and diverse magmatic sources The spatiotemporal changes of slab dip triggered the asynchronous flare‐ups of the Neo‐Tethyan arc

The dynamics of slab detachment and associated geological fingerprints have been inferred from various numerical and analog models. These invariably use a setup with slab‐pull‐driven convergence in which a slab detaches below a mantle‐stationary trench after the arrest of plate convergence due to arrival of continental lithosphere. In contrast, geological reconstructions show that post‐detachment plate convergence is common and that trenches and sutures are rarely mantle‐stationary during detachment. Here, we identify the more realistic kinematic context of slab detachment using the example of the India‐Asia convergent system. We first show that only the India and Himalayas slabs (from India's northern margin) and the Carlsberg slab (from the western margin) unequivocally detached from Indian lithosphere. Several other slabs below the Indian Ocean do not require a Neotethyan origin and may be of Mesotethys and Paleotethys origin. Additionally, the still‐connected slabs are being dragged together with the Indian plate forward (Hindu Kush) or sideways (Burma, Chaman) through the mantle. We show that Indian slab detachment occurred at moving trenches during ongoing plate convergence, providing more realistic geodynamic conditions for use in future numerical and analog experiments. We identify that the actively detaching Hindu Kush slab is a type‐example of this setting, whilst a 25–13 Ma phase of shallow detachment of the Himalayas slab, here reconstructed from plate kinematics and tomography, agrees well with independent, published geological estimates from the Himalayas orogen of slab detachment. The Sulaiman Ranges of Pakistan may hold the geological signatures of detachment of the laterally dragged Carlsberg slab. Key Points Kinematic context of slab detachment Slab detachment during ongoing convergence

Detrital zircon data have recently become available from many different portions of the Tibetan–Himalayan orogen. This study uses 13,441 new or existing U‐Pb ages of zircon crystals from strata in the Lesser Himalayan, Greater Himalayan, and Tethyan sequences in the Himalaya, the Lhasa, Qiangtang, and Nan Shan–Qilian Shan–Altun Shan terranes in Tibet, and platformal strata of the Tarim craton to constrain changes in provenance through time. These constraints provide information about the paleogeographic and tectonic evolution of the Tibet–Himalaya region during Neoproterozoic to Mesozoic time. First‐order conclusions are as follows: (1) Most ages from these crustal fragments are <1.4 Ga, which suggests formation in accretionary orogens involving little pre‐mid‐Proterozoic cratonal material; (2) all fragments south of the Jinsa suture evolved along the northern margin of India as part of a circum‐Gondwana convergent margin system; (3) these Gondwana‐margin assemblages were blanketed by glaciogenic sediment during Carboniferous–Permian time; (4) terranes north of the Jinsa suture formed along the southern margin of the Tarim–North China craton; (5) the northern (Tarim–North China) terranes and Gondwana‐margin assemblages may have been juxtaposed during mid‐Paleozoic time, followed by rifting that formed the Paleo‐Tethys and Meso‐Tethys ocean basins; (6) the abundance of Permian–Triassic arc‐derived detritus in the Lhasa and Qiangtang terranes is interpreted to record their northward migration across the Paleo‐ and Meso‐Tethys ocean basins; and (7) the arrival of India juxtaposed the Tethyan assemblage on its northern margin against the Lhasa terrane, and is the latest in a long history of collisional tectonism. Key Points Tibet is underlain mainly by juvenile terranes Tethyan realm consisted of three separate ocean basins Detrital zircons record changing provenance

The drift history of the Lhasa terrane is crucial for understanding the tectonic evolution of Tethyan Oceans and Jurassic true polar wander. However, high‐quality Middle Jurassic paleomagnetic data from the Lhasa terrane are limited in number. Here we report a combined paleomagnetic and geochronologic study on the Yeba Formation volcanic rocks, dated at ∼170 Ma, from the Lhasa terrane. Robust field and reversal tests indicate that the characteristic remanent magnetizations are primary. Our results provide a reliable Middle Jurassic (∼170 Ma) paleopole at 29.8°N, 180.7°E with A95 = 5.7° and a paleolatitude of 14.4 ± 5.7°N for the Lhasa area. Compared with previous paleomagnetic and geologic evidence, we propose that the Meso‐Tethys Ocean probably began to close in the eastern part at ∼168 Ma and that the Lhasa terrane underwent a ∼2,900 km southward “monster shift” during the Late Jurassic. Plain Language Summary The formation of the Tibetan Plateau followed the breakup of the Gondwana supercontinent and was associated with the demise of several Tethyan Oceans. The Lhasa terrane, which is a long and narrow continental fragment derived from Gondwana, was isolated in the Tethyan Ocean during the Jurassic and finally accreted to the south margin of the Paleo‐Asia continent, leading to the closure of the Meso‐Tethys Ocean. However, when this Meso‐Tethys Ocean closed is still controversial. Our new robust paleomagnetic result shows that the Lhasa terrane was located at ∼14.4°N at ∼170 Ma. Based on available reliable Jurassic paleomagnetic data from the eastern part of the Lhasa and Qiangtang terranes, we suggest that the Meso‐Tethys Ocean began to close in the eastern part at ∼168 Ma. Integrating our critical Middle Jurassic paleomagnetic data with that of the Late Jurassic from the Lhasa terrane, we argue that the Lhasa terrane suffered a ∼2,900 km southward latitudinal shift during the Late Jurassic, which is known as true polar wander. Key Points The Lhasa terrane was located at ∼14.4 ± 5.7°N at ∼170 Ma The Lhasa terrane experienced a ∼2,900 km southward monster shift during the Late Jurassic The closure of the Meso‐Tethys Ocean in the eastern part most likely occurred at ∼168 Ma

The Lhasa‐Qiangtang collision closed the Meso‐Tethys Ocean, but the exact timing of this event remains hotly debated. Here, we present geochronological and paleomagnetic analyses conducted on Cretaceous volcanics from western Qiangtang to constrain the Lhasa‐Qiangtang collision in western Tibet. Our investigations yield a paleolatitude of ∼30.5 ± 5.0°N for western Qiangtang during ca. 110–100 Ma. A reanalysis of previously acquired Mesozoic‐Cenozoic paleomagnetic data from western Qiangtang suggests a stationary position during ca. 136–34 Ma. Examination of paleomagnetic data from western Lhasa reveals a significant reduction in northward paleolatitudinal motion during the Early Cretaceous, dropping from ∼12.3 cm/yr to nearly zero. Integration of our paleomagnetic findings with available geological records has led to conclude that the Lhasa‐Qiangtang collision in western Tibet occurred at ca. 132 Ma. Additionally, we infer that crustal shortening on the order of ∼1,000 km happened between Lhasa and Qiangtang during the Early Cenozoic. Plain Language Summary The Tibetan Plateau comprises multiple different blocks, which originated from the Gondwana in the southern hemisphere. Their convergence histories toward Euraisa have changed the global land‐sea distributions since the Late Paleozoic. The time at which the Lhasa block, one of the Tibetan blocks, accreted to the Qiangtang block to the north remains poorly constrained. In this work, we provide robust data suggesting a latitude of ∼30.5 ± 5.0°N for western Qiangtang during the Early Cretaceous (ca. 110–100 Ma). We also compiled the available latitudinal data from western Tibet in combination with geological observations. We suggest Lhasa collided with Qiangtang during 132 million years ago in western Tibet. Significant shortening of the continental crust by ∼1,000 km between the Lhasa and Qiangtang blocks occurred after their collision. Key Points Western Qiangtang had a paleolatitude of ∼30.5 ± 5.0°N at ca. 110–100 Ma A substantial decrease in the paleolatitudinal motion of western Lhasa occurred in the Early Cretaceous The Lhasa‐Qiangtang collision in western Tibet occurred at ca. 132 Ma

The timing and magnitude of the early Cenozoic surface uplift of the Tibetan Plateau is controversial due to a scarcity of unaltered terrestrial sediments required for palaeoaltimetry techniques. Such information is critical, however, for constraining the geodynamic and palaeoclimatic evolution of the Indian and Eurasian continents and for interpreting global climate, biodiversity and biogeochemical cycles since the Cenozoic. We find that substantial uplift occurred by 63 to 61 million years ago, before the collision of the Indian and Eurasian continental plates, based on comparison of triple oxygen isotopes of modern meteoric waters with epithermal Ag–Pb–Zn deposit quartz veins from the Palaeocene Gangdese Arc in southern Lhasa. Low δ18O and δ17O quartz values are consistent with precipitation from meteoric waters influenced by a large degree of topographic rainout. We show that by 63 to 61 Ma, the Gangdese Arc reached an elevation of ~3.5 km, suggesting that the Gangdese Arc achieved >60% of its current elevation before continent–continent collision. This uplift was probably caused by crustal shortening in response to low-angle subduction of Neo-Tethyan oceanic lithosphere. This early high palaeoelevation estimate for the Himalaya–Tibetan system challenges previous assumptions that southern Tibet uplift required continent–continent collision to achieve substantial topography.The triple oxygen isotope composition of quartz veins indicates that the southern Tibetan Plateau was already around 3.5 km high by 60 million years ago, showing that substantial surface uplift started before collision of the Eurasian and Indian plates.

The controversial history of Indian subduction beneath Asia is crucial to understand the Himalayan orogeny and more in general the geodynamic process of continental subduction. New key information is here presented from the Oligocene‐Pliocene Shiquanhe Basin located in the southwestern Tibetan Plateau. The alluvial‐fan, lacustrine, and braided‐river sediments of the Oligocene Rigongla Formation were non‐conformably deposited onto the Upper Cretaceous Gangdese granitoid rocks and fed from erosion of the batholith itself and of associated Paleogene Linzizong volcanic rocks. Stratigraphic evidence testifies to the development of an orogen‐parallel intracontinental rift along the retro‐side of the Gangdese arc in the Oligocene, at the same time as the Kailas basin formed along the pro‐side of the Gangdese arc. The subsidence of these twin basins may have been caused by steepening of the subducting Indian continental slab or by the passage of a wave of dynamic topography during continuing subduction. Plain Language Summary The convergence and collision of India and Asia leading to the formation of the Himalayan Mountains and Tibetan Plateau (“the roof of the world”) is one of the most significant geological events of the Cenozoic Era. Geophysical data show that rocks of the Indian continent lie beneath southern Tibet, but the early subduction history of India related to the initial topographic grow of the Himalaya remains unclear. We studied the Shiquanhe Basin in southwestern Tibet to investigate the continent's subduction history using stratigraphic, sedimentological, and provenance analyses. Our results indicate that an orogen‐parallel rift developed in southern Tibet during the Oligocene Epoch. Challenging earlier beliefs, we propose two alternative models to explain such event of tectonic extension: steepening of subduction angle or passage of a topographic wave across the subducting plate. The latter hypothesis would also explain the widespread uplift and lack of Oligocene sedimentary deposits recorded all across the front of the Himalayan range. Key Points Oligocene Rigongla Fm. testifies to orogen‐parallel extension along retro‐side of Gangdese arc Shiquanhe Basin passed from extension to compression in Oligocene to Miocene times Oligocene extension was caused by change of Indian subduction angle or wave of dynamic topography

Crustal deformation and hydrothermal percolation related to the India‐Asia collision have caused extensive remagnetization of the Tethyan Himalaya Terrane (THT). The present work identified three phases of regional remagnetization during 62.3–50.0 Ma for the east‐central THT. Consequently, a model of three‐stage India‐Asia collision was proposed. The east‐central THT first collided with the southward migrated southern margin of the Lhasa Terrane (LT) at 5.4 ± 0.9°N during 62.3–60.9 Ma. Subsequently, the THT continuously moved northward and pushed the southern margin of the LT back to its original position prior to the initiation of fore‐arc and back‐arc extension on both sides of the Gangdese magmatic arc. Since the final suturing of the THT with Asia at ∼10°N during 59.8–58.0 Ma, the east‐central THT remained stationary until India collided with it at 10.9 ± 5.1°N at ∼50.0 Ma. Plain Language Summary The collision of India and Asia caused intense tectonic deformation and hydrothermal alteration throughout the Tethyan Himalaya Terrane (THT), which resulted in the large‐scale remagnetization in the THT. The regional remagnetization of the THT can be used to constrain the India‐Asia collision process, on the premise that the time of remagnetization can be determined. Based on this assumption, we measured two representative Paleocene remagnetized components from Early Jurassic limestones in the Gyangze Basin in the east‐central THT. These remagnetized components, combined with non‐remagnetized components and remagnetization events recorded in the adjacent areas, suggest that the east‐central THT experienced three phases of regional remagnetization during 62.3–50.0 Ma. The first and second phases of remagnetization in the north‐central part of the east‐central THT occurred at the paleolatitude of 5.4 ± 0.9°N at 62.3–60.9 Ma and 10.3 ± 1.0°N–9.5 ± 1.1°N at 59.8–58.0 Ma, respectively. The third phase of remagnetization occurred in the southern part of the east‐central THT, at the paleolatitude of 10.9 ± 5.1°N at ∼50.0 Ma. Consequently, a model of three‐stage India‐Asia collision and southward spreading tectonic deformation of the THT was proposed based on these successive remagnetizations. Key Points The east‐central Tethyan Himalaya Terrane (THT) experienced three phases of large‐scale remagnetization during 62.3–50.0 Ma The collision of THT with the Lhasa Terrane commenced at 62.3–60.9 Ma and finished at 59.8–58.5 Ma India finally collided with the THT at the paleolatitude of ∼10.9 ± 5.1°N at ∼50.0 Ma

The surface uplift history of the Tibetan Plateau and Himalaya is among the most interesting topics in geosciences because of its effect on regional and global climate during Cenozoic time, its influence on monsoon intensity, and its reflection of the dynamics of continental plateaus. Models of plateau growth vary in time, from pre-India-Asia collision (e.g., [almost equal to]100 Ma ago) to gradual uplift after the India-Asia collision (e.g., [almost equal to]55 Ma ago) and to more recent abrupt uplift (<7 Ma ago), and vary in space, from northward stepwise growth of topography to simultaneous surface uplift across the plateau. Here, we improve that understanding by presenting geologic and geophysical data from north-central Tibet, including magnetostratigraphy, sedimentology, paleocurrent measurements, and ⁴⁰Ar/³⁹Ar and fission-track studies, to show that the central plateau was elevated by 40 Ma ago. Regions south and north of the central plateau gained elevation significantly later. During Eocene time, the northern boundary of the protoplateau was in the region of the Tanggula Shan. Elevation gain started in pre-Eocene time in the Lhasa and Qiangtang terranes and expanded throughout the Neogene toward its present southern and northern margins in the Himalaya and Qilian Shan.

Paleogeographic reconstruction of Precambrian terranes reworked by Phanerozoic orogens (e.g., the Tibetan Plateau) results in complex lithotectonic relations due to intracrustal reworking by tectonothermal events. Detrital zircon rare earth element (REE) databases at global (global major river sands) and regional (the Gangdese Mountains, southern Tibet) scales reveal trends in LREEN‾/HREEN‾ $\\overline{{\\mathrm{L}\\mathrm{R}\\mathrm{E}\\mathrm{E}}_{\\mathrm{N}}}/\\overline{{\\mathrm{H}\\mathrm{R}\\mathrm{E}\\mathrm{E}}_{\\mathrm{N}}}$ and Eu/Eu* that effectively record the crustal evolution of the source, including crustal thickness and redox state of the magma that generated the zircons. Regional comparisons of these chemical markers provide a new approach for paleogeographic reconstructions that we apply to study the origin of the Lhasa terrane, southern Tibet. Using Precambrian to early Paleozoic sedimentary and igneous rocks in the Lhasa terrane and compiling detrital zircon analyses from the northern margin of Gondwana, we show that the Lhasa terrane had an African affinity in the Rodinia–Gondwana supercontinent cycles (ca. 1.4–0.4 Ga). Plain Language Summary Constraining the paleogeographic positions and affinities of continental fragments plays a crucial role in validating the concept of the supercontinent cycle. However, tracking the evolving paleogeographic position of these fragments, especially for those of Precambrian age, has proven difficult. We explore the potential for solving this problem by using detrital zircon rare earth element (REE) abundances, which are controlled by the magma source depth, protolith type, oxygen fugacity, and magmatic water content of parental melts. We reveal correlations between detrital zircon REE abundances and crustal evolution in different tectonic settings based on global and regional detrital zircon databases. We subsequently demonstrate how detrital zircon REE abundances show that the Lhasa terrane in the southern Tibet is a fragment derived from Africa. Our study provides a new perspective on the paleogeographic reconstruction of continental fragments through Earth's history and thus has important implications for supercontinent research. Key Points Zircon rare earth element (REE) abundances reflect the composition of, and the conditions that generated, the parental melts Trends in detrital zircon REE effectively preserve a crustal evolution history and provide a new approach for paleogeographic reconstruction The Lhasa terrane in the southern Tibet had an African affinity in the Rodinia‐Gondwana supercontinent cycles