The sinistral Altyn Tagh strike‐slip fault demarcates the northern boundary of the Qinghai‐Tibetan Plateau; however, the significance and timing of activity along the fault are debated. Here new apatite and zircon (U‐Th)/He data are presented, revealing the exhumation history of the Altyn Tagh Mountains from crustal depths of ~2–7 km. Studies of rock samples from the Altun Shan region show that they were located close to the surface during the Early Cretaceous and remained so until about 40 Ma. Samples from the Subei and Dangjin Pass areas, on the other hand, record a period of rapid exhumation at 20 ± 2 Ma, and samples from the Qiemo area record a period of continuous exhumation between ~20 and 12 Ma at a rate of mm/year, plus a further rapid cooling event at 7–5.5 Ma. Thus, significantly more exhumation has occurred toward the southwestern section of the Altyn Tagh Fault Zone, indicating a decrease in tectonic uplift toward the northeast since the Miocene. During the late Miocene, the Tarim Block began to subduct beneath the northern Tibetan margin, resulting in rapid exhumation of the central section of the Altyn Tagh Fault Zone. In accordance with previous studies, the present results support a model of northward propagation and expansion of the Qinghai‐Tibetan Plateau during the Cenozoic.

The western North China Craton (NCC) entered a stage of craton thinning concentrated on its margin in the Cenozoic, but its Late‐Cretaceous conditions were previously deduced to be relatively quiescent. Therefore, whether the Late‐Cretaceous tectonic reactivation existed on the margin of this block is critical to understanding how the craton evolved into a thinned one. To investigate this possible margin reactivation in the Late Cretaceous, we apply zircon (U‐Th)/He thermochronology to Taibai Mountain on the southern margin of the western NCC. From an ∼3‐km‐high vertical profile with ages decreasing from 98 ± 5 Ma at the peak to 52 ± 7 Ma at the foot, the age‐elevation relationship suggests the rapid exhumation at ca. 78–71 Ma bracketed by two slow exhumation phases. This interpretation is confirmed by 1D half‐space modeling and QTQt inverse modeling, with the rapid exhumation stage having an exhumation rate of 0.1–0.6 km/Myr and a cooling rate of ∼10°C/Myr. Together with previously reported thermochronological data from the margin of the western NCC, the rapid exhumation at ca. 78–71 Ma implies a reactivated margin in the Late Cretaceous before widespread Cenozoic thinning of the craton margin. This Late‐Cretaceous reactivation likely resulted from WNW‐ESE extension expressed by thermo‐tectonic events, basin subsidence, and volcanism in East Asia. Excluding impacts from climate change, lithospheric delamination, and India subduction beneath Eurasia, we infer that the Late‐Cretaceous reactivation on the margin of the western NCC was driven by the far‐field effect of Izanagi Plate subduction beneath the Eurasian Plate during slab rollback of the subducted plate.

Given that K constitutes about 3 wt.% of Earth's crust and is present in most rock-forming minerals, and that Ar diffusion in minerals is temperature-dependent, Ar-based geochronology (40Ar/39Ar and K–Ar dating) can date most rocks and also reveal their thermal history. This paper reviews recent advances and longstanding limitations in 40Ar/39Ar and K–Ar geochronology, and provides perspectives into future research on Ar-based geochronometers. Over the past two decades, multi-collector noble gas mass spectrometry has witnessed remarkable advancements in both sensitivity and resolution. Successive upgrades of mass spectrometer generations have significantly enhanced the precision of Ar isotope measurements, enabling a comprehensive revision and optimization of 40Ar/39Ar dating standard minerals. To achieve high-precision 40Ar/39Ar dating and minimize inter-laboratory discrepancies, researchers are focusing on refining the potassium decay constant, developing standardized mineral separation techniques, and harmonizing irradiation and data processing protocols. These efforts are pivotal for improving the analytical precision of low-K and young samples, thereby expanding the application frontiers of 40Ar/39Ar geochronology. For in situ planetary dating, the K/Ar method currently remains the only feasible radiometric technique among radioactive isotope systems. Addressing challenges in simultaneous K and Ar measurements will facilitate streamlined acquisition of reliable datasets. Moreover, research is advancing toward a deeper understanding of Ar diffusion behavior in minerals—beyond temperature-dependent volume diffusion—to clarify its impact on 40Ar/39Ar data interpretation and geological significance. To further advance argon-based geochronology, the scientific community is committed to continuous exploration and resolution of methodological limitations inherent in these dating approaches.

Tectonics and climate are the two competitive factors sculpturing landforms. Observations on the Earth surface are affected by signals from both tectonic and climatic agents. How to clarify these signals is a key issue. We categorize factors affecting mountain growth as horizontal (extension, compression, and transpression) and vertical (mantle upwelling and climate change) forces to evaluate the driving forces of accelerated exhumation in Taibai Mountain. Based on apatite (U-Th)/He thermochronology, we document two stages of accelerated exhumation at ca. 52-46 Ma and ca. 24-19 Ma from the age-elevation relationship, confirmed by 1D half-space modeling and QTQt inverse modeling. In the framework of paleostress, the two accelerated exhumation events occurred during transpressional periods in the early Eocene and late Oligocene-early Miocene in East China. These two events were triggered by the localized contractional deformation at the intersection of the North Qinling and Fengxian-Taibai faults: The opposite-direction shearing of these two faults was responsible for the former event with an unroofing magnitude of ~1 km; the same-direction shearing of the two faults resulted in the latter event with an unroofing magnitude of ~0.6 km. The far-field effects of both India-Eurasia collision and Pacific subduction drove the accelerated exhumation at ca. 52-46 Ma. The lateral extrusion of the Tibetan Plateau acted as the main driving force for the accelerated exhumation at ca. 24-19 Ma, which may have been slightly influenced by the intensified Asian summer monsoon in the early Miocene.