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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]

The late Mesozoic tectonic evolution of the eastern North China craton was intimately related with the subduction of the paleo-Pacific plate. This study sheds light on Late Jurassic-Early Cretaceous basin-mountain coupling during paleo-Pacific subduction based on low-temperature thermochronology and geochemical analyses from the easternmost Yanshan fold belt, located at the northern edge of the craton. We performed apatite U-Pb and fission-track double dating and trace element analyses of basement and sedimentary rock samples, integrated with zircon and apatite (U-Th)/He analyses on bedrock samples. Our results revealed that the easternmost Yanshan fold belt experienced two stages of rapid cooling and exhumation in the Middle Jurassic-earliest Cretaceous (ca. 170-140 Ma) and in the Early Cretaceous (ca. 140-90 Ma). The Middle Jurassic-earliest Cretaceous exhumation (ca. 170-140 Ma) is mainly recorded by bedrock along the margins of intermontane basins of the eastern Yanshan fold belt. This exhumation event is consistent with compressional Yanshan movement during the Middle Jurassic-earliest Cretaceous coeval with paleo-Pacific flat-slab subduction. Subsequent Early Cretaceous rapid cooling is ascribed to the progressive evolution of the metamorphic core complexes and associated tectonic exhumation of major plutons of northeastern Asia, which were likely controlled by rollback of the paleo-Pacific slab. A middle Cretaceous (ca. 110-90 Ma) tectonic exhumation event is revealed by very low lag-time values in middle Cretaceous strata. Our findings illustrate the potential of a thermochronology approach that combines single-grain double dating and trace element analyses in synmagmatic orogenic systems, which may find application to other orogenic settings worldwide. [ABSTRACT FROM AUTHOR]

Northeast Asia located at the margin of the Paleo-Pacific/Pacific plate provides a detailed record of subduction-related orogenic activity. In order to shed light on Mesozoic-Cenozoic tectonic processes arising from the complex interaction and juxtaposition of multiple tectonic domains, we performed zircon U-Pb and apatite U-Pb, fission-track (FT) and (U-Th)/He analyses in the Zhangguangcai Range, a major mountain range in northeastern Asia. Our zircon and apatite U-Pb results indicate that most granites in the Zhangguangcai Range were emplaced at shallow crustal levels in the early Jurassic (~200–173 Ma) along with a minor amount of Triassic granites (~232 Ma). Volcanic rocks of the Maoershan and Ningyuancun formations were erupted at ~190–175 Ma and ~182–177 Ma, respectively. This Early Mesozoic magmatic activity is related to subduction of the Mudanjiang oceanic plate that separated the Jiamusi and Songliao blocks. Apatite FT analysis of granites and volcanic rocks reveals three groups of cooling ages clustering at ~193–171 Ma, ~158–129 Ma and ~118–102 Ma, while AHe analysis of granites yielded three groups of cooling ages at ~149–135 Ma, ~106–85 Ma and ~57–48 Ma. Based on these data and thermal history modelling, we propose that the central Zhangguangcai Range experienced episodic, multi-stage exhumation at shallow crustal levels since the Jurassic. Early-Middle Jurassic exhumation took place during the closure of the Mudanjiang Ocean, which resulted in unroofing of granites in the central Zhangguangcai Range and topographic growth of the Songliao block. Late Jurassic-Early Cretaceous exhumation occurred within an extensional tectonic setting, which has previously been documented across northeast Asia. Such exhumation could have been linked to lithosphere delamination and resulted in basin and range topography style, prior to the change in subduction parameters of the Paleo-Pacific plate and/or collision and strike-slip translation of the Okhotomorsk block in the Late Cretaceous. • Most of the granites in the Zhangguangcai Range were emplaced at shallow crustal levels in the early Jurassic. • The Zhangguangcai Range experienced pulsed Mesozoic exhumation. • Early to Middle Jurassic exhumation resulted in the unroofing of granites in the central Zhangguangcai Range. • Late Jurassic-Early Cretaceous exhumation likely resulted in a basin and range topography. [ABSTRACT FROM AUTHOR]