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The Early Cenozoic sedimentary archives of Tibet are crucial for elucidating the geodynamic processes related to continental collision, particularly crustal deformation and shortening. However, the lack of a reliable chronostratigraphic framework for the Cenozoic sedimentary basins in central Tibet has hindered a comprehensive understanding of the influence of the continuous India‐Asia convergence process on the tectonic evolution of the Tibetan hinterland. Here, we report new magnetostratigraphic ages and paleomagnetic results for the Niubao Formation exposed in the northern bank of the Siling Co. Positive field tests and microscopic observations suggest that the remanence is primary. We determine that the depositional age of the measured section was between 59.2 and 48.6 Ma. Our results reveal that the paleogeographic location of the Bangong‐Nujiang Suture Zone during the Late Paleocene–Early Eocene was 25.4 ± 2.1°N, thus supporting the model of two‐stage collision between India and Asia. Plain Language Summary: The tectono‐sedimentary evolution of the Cenozoic terrestrial sedimentary basins in the Tibetan Plateau was a long‐term response to Cenozoic continental collision and was critical for both constraining the amount of crustal shortening of the Asian continent and for paleogeographic reconstruction of the plateau. Nonetheless, the ages of the basins are controversial because of the discordance between radiometric dating results and paleontological ages. Siling Co is the geographic boundary between the Lunpola and Nima Basins, and the Niubao Formation is widely exposed on its northeastern margin, providing excellent research materials for studying the paleogeographic evolution of the plateau. Hence, we established a reliable magnetostratigraphic sequence of the Niubao Formation in northwestern Siling Co, combined with U‐Pb chronology, and constrained its age to 59.2–48.6 Ma. Our updated paleomagnetic results indicate that the paleolatitude of the Bangong‐Nujiang Suture Zone was 25.4 ± 2.1°N during the Late Paleocene–Early Eocene. Combined with the published paleomagnetic data from the intra‐oceanic arc, we suggest that the collision between the Asian and Indian continents had at least two stages and that the paleogeographic location of the collision was above 20°N. Key Points: Detrital zircon U‐Pb ages and paleomagnetic polarity patterns indicate that the Niubao Formation was deposited at 59.2–48.6 MaThe Bangong‐Nujiang Suture Zone was located at 25.4 ± 2.1°N during the Paleocene–EoceneThe amount of crustal shortening in the central Tibetan Plateau since 60 Ma is likely to be 780 ± 330 km [ABSTRACT FROM AUTHOR]

Quaternary unconsolidated sediments are pronouncedly widespread features on the planetary surface, documenting significant geological signals of earth surface processes, climate change and biogeochemical cycles. The extensive unconsolidated deposits play a vital role in natural hazards and Anthropogenic activities, especially in alpine regions where massive unconsolidated materials are produced. However, the spatial distribution and total volume of unconsolidated sediments across the Yarlung Tsangpo River Basin (YTRB) remain largely unknown due to the limitation of traditional field surveys and on‐site measurements as well as the complex landscape in the remote area. This study presents the datasets for the systematic distribution and spatial accumulation of unconsolidated sediments across the Yarlung Tsangpo River Basin, southern Tibet. Combining remotely sensed data with numerous field investigations, an integrated method based on image processing and kriging interpolation‐pixel integration was performed to semi‐automatically classify and quantify the unconsolidated sediments. Eleven categories of sediments were mapped and their total accumulation is estimated at approximately 4.97 × 1011 t. Ultimately, 17 groups of classification and thickness maps were derived, revealing the distribution and volume of unconsolidated and Quaternary sediments. The datasets fill the gaps in comprehensive investigations of unconsolidated sediments for YTRB, and provide a fundamental database to support the scientific understanding of potential linkages between the distribution of unconsolidated sediments with environmental changes and human activities. [ABSTRACT FROM AUTHOR]

The Namche Barwa Syntaxis (NBS) is one of the most productive detrital factories on Earth. Previous studies have shown that the NBS supplies large amounts of sediment to the Brahmaputra River, although the sources and controlling factors of sediment production have not been ascertained in detail. This study presents petrographic and heavy‐mineral data for 43 sand samples collected in the Yarlung and Parlung river catchments covering the entire NBS and surrounding areas. Combined with U–Pb ages of detrital zircons, our data indicate that 89 ± 11% of Yarlung River sediments downstream of the NBS are produced in the Yarlung and Parlung gorges. The annual sediment flux of the Yarlung River increases by a factor of 20 within ca. 250 km from upstream of the NBS (ca. 10 Mt) to downstream (ca. 200 Mt/a). The Yarlung and Parlung gorges, representing only ca. 1% of the Yarlung‐Brahmaputra catchment area, contribute 74 ± 9% of the total Brahmaputra sediment flux. Average interannual erosion rates in the Yarlung and Parlung gorges corresponding to these fluxes are calculated to be 9.2 ± 1.2 mm/a and 6.5 ± 2.1 mm/a respectively. Focused erosion of the Namche Barwa Complex and Yarlung Suture Zone in the gorge, where high‐grade metamorphic rocks are exposed, is a consequence of high channel steepness (ksn values up to 800–1800), high stream power and extreme events including frequent earthquakes and landslides. The coupling between surface erosion and tectonic uplift in the Yarlung Gorge is in full agreement with the tectonic aneurism model of NBS evolution. [ABSTRACT FROM AUTHOR]

The Qiangtang terrane preserves an important record of the growth of the Tibetan Plateau since the Mesozoic; however, its deformation and cooling history remain poorly understood. To unravel this issue, we conducted geological mapping in the Esima area and detrital apatite fission track and (U–Th)/He analyses of the Esima–Rongtang region in the east segment of Central Qiangtang terrane. Our results indicate that the east segment underwent two stages of structural deformation and rapid cooling during 120–110 Ma and 55–38 Ma. By combining our results with those of previous studies of the deformation and cooling history in the west segment, we reconstructed the early spatial and temporal geological evolution of the Central Qiangtang terrane since the Late Jurassic–Early Cretaceous. The structural deformation and cooling of the west segment at 150–130 Ma was related to northward flat subduction of the Bangong–Nujiang oceanic slab. The structural deformation and cooling of the east segment at 120–110 Ma and the west segment at 110–70 Ma was controlled by oblique convergence between Lhasa and Qiangtang terranes. The structural deformation and cooling of the west and east segments at 55–38 Ma was associated with northward intracontinental subduction beneath the Qiangtang terrane induced by the Indo–Asian collision. [ABSTRACT FROM AUTHOR]

The growth of central Tibet remains elusory, albeit important in evaluating different topographic growth models accounting for the Tibetan Plateau development. Thermochronological records in the northern Qiangtang terrane (QT) provide valuable information for investigating the cooling and exhumation history in central Tibet. New apatite fission track data, assisted by inverse thermal modelling, reveal two stages of accelerated cooling. The Early Cretaceous cooling is related with refrigeration of the QT and exhumation probably induced by crustal shortening. The Eocene‐Oligocene renewed cooling reflects the far‐field contraction after the onset of the India‐Asia collision and Cenozoic crustal shortening deformation in the QT, coupled with thermal relaxation and transient lithospheric removal. Our data support models indicating that Cretaceous crustal shortening produced a thickened crust in the QT, whereas the present‐day elevation was established during Eocene‐Oligocene due to crustal shortening, continental subduction and lithospheric delamination. [ABSTRACT FROM AUTHOR]

The Central Tibetan Mountain Range (CTMR) exposes the oldest strata in the Qiangtang Terrane and may record the most complete exhumation history prior to and post‐collision of India and Asia. This article presents apatite and zircon (U–Th)/He thermochronology data of granites from the CTMR. Zircon (U–Th)/He single grain ages range from 116 to 191 Ma, while apatite (U–Th)/He single grain ages vary from 54 to 94 Ma. Thermal modelling results based on (U–Th)/He ages of apatite and zircon indicate that episodic rapid exhumations occurred at the Middle‐Late Jurassic and the Late Cretaceous, respectively. The Middle‐Late Jurassic exhumation is consistent with the provenance analysis of Jurassic strata in the South (SQT) and North Qiangtang Terrane (NQT) which suggested they were derived from the CTMR. This stage of rapid exhumation might be attributed to the northward ridge subduction of the Bangong‐Nujiang Ocean. The Late Cretaceous relatively rapid exhumation is compatible with the angular unconformity between the Abushan Formation and the underlying marine strata. This stage of exhumation may be caused by the collision between Lhasa and QT. Our results, combined with the crust shortening and adakitic rocks in the SQT during the Late Cretaceous, provide robust evidence for crustal thickening and early uplift of central Tibetan Plateau prior to the India‐Asia collision. The CTMR experienced very low exhumation since the early Eocene, implying that low‐relief topography had been established at high elevation with internal drainage prior to India‐Asia collision. [ABSTRACT FROM AUTHOR]