Dynamic drainage reorganization in Eastern Tibet: Insights from the Yangtze River first bend

Earth and Planetary Science Letters
By: , and 

Links

Abstract

The modern drainage network of eastern Tibet is widely believed to have developed through a series of river capture and flow reversal events; however, the timing and mechanisms driving this reorganization remain contentious. Among these events, the river capture that formed the First Bend of the Yangtze River (YFB) stands out as both iconic and particularly debated. Here we present sedimentary provenance data from the Late Miocene–Quaternary Dali Basin, located south of the YFB, which indicate that a southward-flowing Jinsha River (i.e., the present-day upper Yangtze River) sourced sediment to the Dali basin at ∼7.4–6.4 Ma in a drainage configuration different from that of today. Because this interval postdates the initial establishment of a near-modern Jinsha River system prior to the Miocene, our results imply at least two discrete fluvial reorganizations occurred at the YFB—one preceding ∼7.4 Ma and another following ∼6.4 Ma. By integrating these findings with landscape evolution modeling, we infer that the initiation of rapid uplift of the Yulong-Haba Mountains and the Diancang Shan may have been responsible for these drainage reorganizations. These results underscore that Cenozoic drainage systems on the eastern Tibetan Plateau have evolved dynamically on a short timescale of ∼105–106-year, rather than remaining in a long-term stationary configuration on ∼107-year timescales.

Suggested Citation

Zhao, X., Li, Y., Zhang, H., Lease, R.O., Wang, Y., Hao, Y., Ma, Z., Xie, H., Kang, H., Xiong, J., and Zhang, P., 2026, Dynamic drainage reorganization in Eastern Tibet: Insights from the Yangtze River first bend: Earth and Planetary Science Letters, v. 686, 120054, 13 p., https://doi.org/10.1016/j.epsl.2026.120054.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Dynamic drainage reorganization in Eastern Tibet: Insights from the Yangtze River first bend
Series title Earth and Planetary Science Letters
DOI 10.1016/j.epsl.2026.120054
Volume 686
Publication Date April 22, 2026
Year Published 2026
Language English
Publisher Elsevier
Contributing office(s) Alaska Science Center Geology Minerals
Description 120054, 13 p.
Country China
Other Geospatial eastern Tibetan Plateau, first bend of the Yangtze River
Additional publication details