[Objective] As an intracontinental orogenic belt reactivated since the Cenozoic by the far-field effect of the India-Asia collision, the Tianshan’s Cenozoic tectonic evolution is key to understanding intracontinental deformation mechanisms. [Methods] Based on stratigraphic sedimentary characteristics and provenance tracing of a section on the northern margin of the Turpan Basin (south of the Bogda Shan), the Late Cretaceous—Cenozoic tectonic and geomorphic evolution of the East Tianshan and its adjacent region has been constrained. [Results] Field investigations reveal that the Paleocene and lower Oligocene strata in this area consist predominantly of red mudstones, indicating a lacustrine environment and stable tectonic conditions. The uppermost Cretaceous and Eocene strata contain conglomerate deposits with relatively small thickness and clast diameters, suggesting tectonic uplift of the Bogda Shan but with weak intensity. In contrast, the upper Oligocene to Pliocene strata are composed of extremely thick, coarse conglomerates, reflecting long-term and intense tectonic activity. Detrital zircon U-Pb ages show that from the Late Cretaceous to the Oligocene, the northern Turpan Basin continuously received detrital material from the West Tianshan, implying low topographic relief of the Bogda Shan during this period. Since the Miocene, however, the Bogda Shan has become the primary sediment source, indicating its rapid tectonic uplift. [Conclusions] In summary, the Bogda Shan remained tectonically stable with low relief during the Late Cretaceous—Oligocene. Since the late Oligocene, it has undergone intense deformation and rapid uplift, becoming the sole provenance area for the northern Turpan Basin. [Significance] This study refines the Cenozoic tectono-geomorphic evolution of the East Tianshan, thereby contributing to a better understanding of the intracontinental deformation processes resulting from the India-Asia collision.
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