Formation of the Yangtze Three Gorges: Insights from detrital apatite fission‐track dating of sediments from the Jianghan Basin

Abstract

The establishment of the course of the modern Yangtze River is a topic of ongoing debate, with the formation of the Three Gorges, incised in the Huangling Massif, representing the key event under discussion. Downstream of the Three Gorges, the Cenozoic succession of the Jianghan Basin has been investigated to detect the moment of incision into the Three Gorges. Detrital apatite fission-track data from Eocene to Miocene sediments drilled in the Jianghan Basin suggest that material was supplied by the Dabie, Qinling and Jiangnan Orogens during Eocene to early Oligocene times.At late Oligocene, the source of sediments switched to the Huangling Massif, implying incision of the Three Gorges. We therefore propose that the modern Yangtze River system formed at the late Oligocene.

Meso–Cenozoic Exhumation in the South Qinling Shan (Central China) Recorded by Detrital Apatite Fission-Track Dating of Modern River Sediments

“…The eastern parts of the South Qinling Shan also underwent rapid exhumation during the Late Eocene (35-30 Ma; Figure 7(31)), as described by Richardson et al [16] and Ge et al [93]. During the Eocene period, the relationship between the South Qinling Shan and Jianghan Basin was further strengthened through basin-mountain coupling [94,95] (Figure 7(32)). The bedrock apatite fission-track age in the vertical section is predominantly focused on 35 Ma, suggesting that rapid exhumation occurred in the North Qinling Shan during the Late Eocene [13,96] (Figure 7(33)).…”