Fluvial aggradation and incision processes in eastern Tibetan plateau and their relationship to glacial activities

Since the establishment of the classic Theory of Alpine Glacial Cycles, a close relationship between glacial activities and fluvial terrace development has been observed. However, problems such as the extent and mechanisms through which glacier advances influence downstream fluvial aggradation, are not fully understood. The Aba Basin, located on the eastern Tibetan Plateau, features well-developed river terraces. In conjunction with this, the upstream Nianbaoyeze Mountains have undergone intense glacial activities during glacial periods. The integration of these features make this source-to-sink system an ideal site to study these problems. In this work, we utilized Luminescence and Radiocarbon dating methods to reconstruct terrace sequences in the Aba Basin. Furthermore, geochemical analyses were undertaken to delineate trends in provenance variation during terrace aggradation periods, and subsequently to assess the impact of sediment supply from the Nianbaoyeze Mountains. Integrating our analysis of fluvial evolution in the Aba Basin with glacier activities from the Nianbaoyeze region and correlating them with regional and global paleoclimate data, we present detailed insights into how glacial activities have driven terrace formation in the Tibetan Plateau since the late Pleistocene. Our research offers new perspectives on the fluvial processes in periglacial regions, enhancing the understanding of the interplays between fluvial landform dynamics and glacial-interglacial cycles.