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Global cooling and/or Tibetan Plateau uplift have long been regarded as the principal drivers of late Cenozoic central Asian aridification and the resulting widespread accumulation of eolian deposits in eastern Asia. However, these two factors are unable to form large source areas of fine‐grained sediments enhancing eolian deposition synchronously from northern Tibet to North Pacific. Here we provide magnetostratigraphic and detrital apatite fission‐track evidence for a major sediment recycling event in northern Tibet at ∼8 Ma, coeval with a sudden increase in eolian deposition, which we ascribe to syntectonic erosion of uplifted friable fluvio‐lacustrine sediments and selective entrainment by the westerly winds during basin deformation. Our results emphasize the importance of widespread and persistent occurrence of fine‐grained sediments along the pathway of westerlies to produce voluminous dust deposits. These findings suggest that the onset of eolian deposition may not be directly related to global cooling or uplift of mountain ranges. Plain Language Summary: A proper analysis of tectonic events and sedimentological processes is key to understanding the controlling factors of enhanced eolian deposition documented synchronously from northern Tibet to the North Pacific since ∼8 Ma. In addition to the hypothesized sizable inland deserts, potential dust sources have been considered to be piedmont fluvial sediments and dry lake sediments in northern Tibet and central Asia. However, almost all these suggestions fail to explain the rapid expansion of eolian deposition in the Chinese Loess Plateau, which required a substantial increase in the availability of fine‐grained silts and clays in the source areas. Here we confirm a major sediment recycling event favored by basin deformation in northern Tibet through an integrated analysis of magnetostratigraphy and detrital apatite fission tracks. This event led to the uplift of a large amount of friable fluvio‐lacustrine sediments along the fold‐thrust belts of northern Tibet, which coincided with this sudden increase of eolian deposition at ∼8 Ma. We suggest a causal link, favored by the action of the westerly winds, between uplift of basin strata in northern Tibet, sediment recycling and the substantial expansion of eolian deposition in eastern Asia, which gains support from multi‐proxy analyses of fluvio‐lacustrine sedimentary successions. Key Points: A sediment recycling event starting at ∼8 Ma is confirmed by new magnetostratigraphic and detrital apatite fission‐track dataA new syntectonic sediment recycling model is proposed to explain the origin of eolian deposition in eastern AsiaA connection between sediment recycling and eolian deposition is supported by multi‐proxy datasets of fluvio‐lacustrine deposits [ABSTRACT FROM AUTHOR]

There is an ongoing debate regarding the paleogeographic evolution of the Qaidam Block (37.3 °N/96.4 °E) in northwest China during the late Paleozoic. To provide a reliable constraint on the paleogeographic reconstruction and to determine the relationship with the adjacent area, we performed a paleomagnetic investigation of Early and Late Carboniferous sediments from the Qaidam Block. Stepwise thermal demagnetization successfully isolated high unblocking-temperature characteristic directions from the samples. The tilt-corrected mean direction of the Early Carboniferous sediments is Ds / Is = 298.6°/− 46.4° with α 95 = 4.7° and N = 15 sites, corresponding to a paleopole at − 3.2 °N, 147.5 °E with A 95 = 4.8°. The Late Carboniferous paleomagnetic direction is Ds / Is = 320.1°/− 46.1° with α 95 = 5.3° and N = 8 sites, corresponding to a paleopole at − 15.1 °N, 132.2 °E with A 95 = 5.4°. A positive fold test for the Early Carboniferous paleomagnetic directions, and consistency with the Kiaman reversed superchron for the Late Carboniferous paleomagnetic directions, indicates the primary origin of the characteristic remanence of the studied section. The new paleomagnetic results suggest that the Qaidam Block was located at about 27 °N and did not undergo significant N-S movement during the Carboniferous. However, the Qaidam Block experienced a counter-clockwise rotation of about 21° during this period. Comparisons of the paleomagnetic results from the major blocks of Central Asia suggest that the Qaidam Block may have experienced a relatively rapid northward movement and collided with the Tarim Block after the Late Permian. Based on the paleomagnetic poles of the Qaidam Block and adjacent blocks, we present a tentative paleogeographic reconstruction for central Asia during the Early and Late Carboniferous. [ABSTRACT FROM AUTHOR]

The Pamir Salient and Southwestern Tien Shan belong to two different systems, which collided due to the continuous northward drift of the Indian Plate during the Cenozoic, resulting in a shortening of ~ 300 km. The uplift history and kinematic evolution of the Pamir-Southwestern Tien Shan remain unclear. In this study, we chose the 2025 m-thick Pakabulake formation in the East Wuqia section, at the southern-most margin of the Southwestern Tien Shan system, to obtain a high-resolution magnetostratigraphic record spanning ~ 16.61 Ma to ~ 9.78 Ma. Based on its high sedimentation rate, stable ca. E-W paleocurrents and stable magnetic susceptibility values, the nearby Southwestern Tien Shan was inferred to have undergone stable uplift during this period of sedimentation. Combining our results with the previous low-temperature thermochronology, magnetostratigraphy and re-calculated block rotations, we conclude that four episodic uplift events occurred in the Pamir-Southwestern Tien Shan during the Cenozoic, at times of ~ 50–40 Ma, ~ 35–16 Ma, ~ 11–7 Ma and < 5 Ma, and that the first episodic uplift only occurred in the Pamir Salient. In addition, the Pamir Salient underwent a tectonic transformation from entire- to a half-oroclinal bending rotation during the Miocene, caused by activity along the Karakorum Fault and Kashgar-Yecheng Transfer System. [ABSTRACT FROM AUTHOR]

The collision between the Qiangtang and Lhasa blocks is a critical factor in understanding the geodynamics of the central Tibetan Plateau. However, the process of the Qiangtang-Lhasa collision remains contentious. A direct way to study the history of the Qiangtang-Lhasa collision would be to determine the evolution of the paleolatitude positions of the Qiangtang and Lhasa blocks during the Jurassic-Cretaceous. In this study, we present a combined paleomagnetic and geochronological study of the Early Cretaceous volcanic rocks dated at ~120–115 Ma in the western Qiangtang block. Stepwise thermal demagnetization succeeded in isolating the high-temperature characteristic directions of the samples. The tilt-corrected mean direction of the 16 sampling sites was Ds = 60.9°, Is = 45.9° with ɑ 95 = 4.4°, which indicates that the Qiangtang block was situated at 27.6 ± 5.0°N during the Early Cretaceous (~120–115 Ma) (reference point: 32.9°N, 83.5°E). Our new data combined with previous reliable Cretaceous paleomagnetic results for the Lhasa block indicate that the collision between the western parts of the Qiangtang and Lhasa blocks may occur later than 115 Ma. The extent of the western segment of the Bangong-Nujiang Tethys Ocean was ~825 ± 600 km (7.5° ± 5.5° in latitude) at 120–115 Ma. • The southwestern margin of the Qiangtang block was situated at 27.6 ± 5.0°N at 120–115 Ma. • The extent of the western segment of the Bangong-Nujiang Tethys Ocean was ~825 ± 600 km at 120–115 Ma. • The collision between the western parts of the Qiangtang and Lhasa blocks occurred later than 115 Ma. [ABSTRACT FROM AUTHOR]