Topographic growth of the northeastern Tibetan Plateau during the middle-late Miocene: Insights from integrated provenance analysis in the NE Qaidam Basin

The development history of high topography in the northeastern (NE) Tibetan Plateau is essential to test various plateau growth models and understand plateau construction. We present integrated provenance data from the NE Qaidam Basin, south of the Qilian Shan. Results show an increase in carbonate lithics, an increase in Al2O3/SiO2 ratios, a negative shift in epsilon(Nd) values and an appearance of large amounts of Precambrian zircon grains in the period of ca. 13-8 Ma, arguing that the sediment source of the NE Qaidam Basin may have shifted from the East Kunlun Shan to the Qilian Shan during this time interval. We infer that significant topographic growth of the southern Qilian Shan occurred during the middle-late Miocene. Along with widespread middle to late Miocene deformation records across the Qilian Shan and abruptly shifts on provenance, sedimentary facies and climate indexes in its surrounding basins, present high topography of the NE Tibetan Plateau may have been established since the middle-late Miocene.

Automated summary

Research indicates that during the middle to late Miocene, around 13-8 million years ago, the sediment source of the northeastern Qaidam Basin may have shifted from the East Kunlun Shan to the Qilian Shan, suggesting significant topographic growth in the southern Qilian Shan during this period. This is supported by widespread deformation records in the Qilian Shan during the middle to late Miocene, as well as abrupt changes in provenance, sedimentary facies, and climate indexes in surrounding basins, implying that the high topography of the NE Tibetan Plateau may have been established since the middle to late Miocene.