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The Yulin River in the northern Tibetan Plateau, consists of multiple geomorphological features, including alluvial fans, fluvial terraces, and river profile knickpoints. Collectively, these provide a natural laboratory for exploring the late Quaternary fluvial landform evolution in response to both climatic change and tectonic activities in the region of the Altyn Tagh Fault. In this study, we investigated the distribution, sequences and sediment characteristics of the fluvial landforms along the Yulin River based on high-precision (0.5 m-resolution) Worldview satellite images and field observations. Mid-Pleistocene alluvial fans formed the highest fluvial landform surface into which ten major inset fluvial terraces were developed, distributed along three stream segments. Real-time kinematic global positioning system (RTK-GPS) measurement of terrace surfaces and the modern river longitudinal profiles was conducted across the Dongbatu Shan to show fluvial landform geometry and tectonic deformation. Fluvial terrace surfaces were deformed due to fault uplift as illustrated by spatially variable surface geometries. The chronological sequences of terraces along the Yulin River since 160 ka were reconstructed based on 10Be terrestrial cosmogenic nuclides (TCNs) dating. Results indicated that river incision occurred mainly during periods of climate transition, suggesting that terrace evolution was partly controlled by climate changes. Moreover, terrace exposure ages showed an upstream younging trend along the river, demonstrating a probable response to knickpoint retreat. Combined with terrace deformation and ages, fault uplift rates were constrained, which were lower than the river incision rates during the Late Quaternary, indicating that crustal shortening was mainly absorbed by the growth of the regional anticline. Collectively, our results suggest that the evolution of fluvial landforms along the Yulin River is a function of interplay between regional tectonic activities and climatic changes, which is significant to understand the NW-outward splay of the Altyn Tagh Fault. • Yulin River fluvial landform sequences since 160 ka were established via 10Be dating. • Knickpoint recession plays a significant role in terrace evolution along Yulin River. • Fault uplift rates were lower than the river incision rates in the Late Pleistocene. • Tectonic deformation was absorbed mainly by the uplift of the entire anticline. • Climate and tectonic uplift control river incision and fluvial landform evolution. [ABSTRACT FROM AUTHOR]

Intense compression following the India-Asia collision is responsible for basin sedimentation and deformation in the northeastern Tibetan Plateau. Despite significant advances in elucidating basin development and associated deformation, debate continues regarding the onset of basin sedimentation along the plateau margin. One of the debated issues is whether the Cenozoic basin sedimentation was a response to deformation soon after plate collision at approximately 50 Ma, or if it was related to a former stress field overprinted by an expanded plateau 20–30 Ma later. To address this issue, a complete spatiotemporal pattern of deformation is central to understanding the basin development linked to plateau growth. Here, we report new deformation constraints in the Baima Basin, a depocenter located on the northern margin of the Arcuate Ranges area (AR), northeastern Tibetan Plateau. A combination of high-resolution magnetostratigraphic results, 10Be/26Al cosmogenic nuclide burial ages and previous chronological constraints provides a prolonged sedimentary history, containing the onset of a N–S-trending normal-faulting basin in the late Eocene, basin subsidence for predominant deposition at 13.6–6.0 Ma and dextral transpression since 6.0 Ma. In the predominant deposition stage, the basin accumulated upward fining sediments under a relatively stable climate context. Dextral transpression along the N–S-striking fault disrupted the once prevailing subsidence at ca. 6.0 Ma, resulting in growth strata, an increase in coarse-grained deposits and lower accumulation rates in the Baima Basin. Dextral strike-slip was probably caused by stepwise forward propagation beginning approximately 8 Ma in the AR, which may be related to late Miocene plateau-scale strike-slip motion. These new data imply that predominant sedimentation and basin deformation in response to plateau expansion could have occurred much later than the onset of the basin. • Predominant basin sedimentation by normal faulting prevailed around ca. 13–8 Ma. • Stepwise forward compression overprinted the normal-faulting basins since ca. 8 Ma. • Growth strata indicate northward compression since ca. 6 Ma in the Baima Basin. [ABSTRACT FROM AUTHOR]