Cenozoic surface Earth system evolution and dynamic palaeogeomorphic reconstruction from the Tibet Plateau to the Western Pacific linked by the Yangtze River

The formation of the modern east-flowing Yangtze River is marked by the incision of the Three Gorges (TG) between the Sichuan and Jianghan basins. However, it is still controversial as to the timing of the TG incision, due to diverse tectonic, sedimentological and geochemical records. These records, together with other geological data (i.e. curves of palaeoclimate and sea-level fluctuation), are critical parameters in the software Badlands, a tool to simulate large-scale and long-term geomorphic evolution. Using Badlands, we modelled the geomorphology and drainage evolutionary process of the Yangtze River since the Late Cretaceous (80 Ma). It revealed that the drainage system in the Sichuan Basin was gradually reversed from southward flowing to northward flowing during the Late Eocene and the Oligocene, due to the periodic uplift of the eastern Tibet Plateau and the southwestern Yangtze Block. Coevally, the Jianghan Basin experienced a base-level drop, which was controlled by the collapse of a palaeocoastal mountain range and subsequent continental rifting along the SE China continental margin. The tectono-geomorphic interplay eventually led to the incision of the TG in the Late Oligocene ( c . 24 Ma), when the drainage system of the Upper Yangtze River was captured by the Middle–Lower Yangtze River.