东昆仑山新生代初始广泛隆升始于约20MaOA

[Objective]The uplift of the Tibetan Plateau is a direct expression of the Earth's interior geodynamic processes caused by the impact of the collision of the India-Eurasia Plates.Investigating the uplift history is essential to clarify the deformation mechanisms of the continental lithosphere,and remains a central scientific issue in deci-phering interactions of the Earth's multiple spheres.Despite extensive studies,intense debate continues regarding the plateau uplift and expansion.The timing of the uplift in the northern Tibetan Plateau is pivotal for resolving these questions;the Eastern Kunlun Mountains are a crucial geomorphic boundary,since they form the southern margin of the northern plateau and were a critical conduit for the northward propagation of collision-related stresses.The East-ern Kunlun range is an ideal area for studying the uplift processes of the northern Tibetan Plateau,but the timing of their initial uplift remains highly debated.[Methods]A comprehensive low-temperature thermochronological analysis of the bedrock in the Eastern Kunlun Mountains was conducted to constrain the Cenozoic uplift history.It included in-tegrating the results of 37 low-temperature studies in the region comprising 203 apatite fission track data points and 142 apatite(U-Th)/He data points.Sample selection criteria for low-temperature thermochronology were strictly fol-lowed during dataset compilation,and a series of rigorous data-screening strategies were established to minimise dis-turbances from experimental errors,sample characteristics and complex thermal histories to enhance the accuracy and reliability of the dataset.The analysis involved three steps:(1)the low-temperature thermochronological age dis-tribution was visualised;(2)the relationship between mean track length and age was established;and(3)thermal history modelling results were compiled.Integrating these enabled a detailed,comprehensive low-temperature ther-mochronology framework to assess the uplift history of the Eastern Kunlun Mountains in the Cenozoic.[Results and Conclusions]Since the Upper Cretaceous,the surface rocks of the Eastern Kunlun Mountains have generally re-mained in a relatively stable or slowly cooling state within the apatite fission track partial annealing zone and the apa-tite(U-Th)/He partial retention zone.The Eastern Kunlun Mountains did not form a significant topographic barrier during the Paleogene,and the drainage systems of adjacent basins were likely interconnected.Although the possibili-ty cannot be entirely excluded that sporadic highlands in local areas of the Eastern Kunlun Mountains provided sedi-ment sources for adjacent basins,the data indicates that widespread uplift of the Eastern Kunlun Mountains did not begin to occur until about 20 Ma,when rapid uplift took place causing an estimated rock displacement not less than approximately 2 km relative to the surface,corresponding to the length of the rock column recording Early Miocene apatite(U-Th)/He(22-17 Ma)and apatite fission track(23-15 Ma)age components.This finding provides new evi-dence for understanding the timing of the paleo-Qaidam Basin disintegration,the paleo-elevation history of the north-ern Tibetan Plateau in the Early Miocene,and the uplift processes and dynamic mechanisms involved.