Acta Geographica Sinica ›› 2018, Vol. 73 ›› Issue (9): 1728-1736.doi: 10.11821/dlxb201809009

• Earth Surface Process • Previous Articles     Next Articles

The age of river terraces in the Jinjiangjie reach of the Jinsha River and its implications for valley and drainage evolution

DONG Ming1(),SU Huai1(),SHI Zhengtao1,MING Qingzhong2,HE Huili3   

  1. 1. College of Tourism and Geography Sciences, Yunnan Normal University, Kunming 650500, China
    2. Research Institute of Tourism and Culture Industry, Yunnan University of Finance and Economics, Kunming 650221, China
    3. Kunming Institute of Botany, CAS, Kunming 650201, China
  • Received:2017-09-18 Online:2018-09-25 Published:2018-09-19
  • Supported by:
    National Natural Science Foundation of China, No.41762014, No.41462007, No.41362010, No.41001010;Applied Basic Research Project of Yunnan Province, No.2013FZ047


The Jinsha River has attracted considerable attention for nearly a century due to its unusual drainage basin morphology. Most models describing its evolution suggest that the modern Jinsha River, draining the Tibetan Plateau margin, was once a tributary to a single, southward river system called "Paleo-Red River", which drained into the South China Sea and then its flow direction changed to east to join the Yangtze River due to river capture. The Red River submarine fan, considered to have been primarily fed by the Paleo-Red River system, suddenly disappeared at 5.5 Ma provides an important chronological constraint on this reorganization of drainage lines and reversal event. However, no geomorphic evidence has been found to agree with this hypothesized timeframe. Here, we present electron spin resonance (ESR) ages from eight terraces preserved in the Jinjiangjie reach of the Jinsha River together with their GPS altimetry data. Their ages from old to young are 1.07 Ma, 0.70 Ma, 0.65 Ma, 0.51 Ma, 0.47 Ma, 0.44 Ma, 0.30 Ma and 0.18 Ma, with a calculated average river incision rate of 147 mm/ka since 1.0 Ma. The paleo-topography, reconstructed by filling the deeply incised river gorges with digital elevation model (DEM) data, shows that the upper reach of the Paleo-Red River was captured by the Yangtze River and changed its flow direction eastward at the time of disruption of the 2000 m asl paleo-topographic surface in the Jinsha River drainage basin. The age of the paleo-topographic surface formation would be approximately 5.5 Ma using the average river incision rate extrapolation, suggesting that the present Jinsha River system was born after 5.5 Ma. This data support the chronological constraint from the Red River submarine fan, and hypothesized evolution of the Jinsha River.

Key words: Jinsha River, Jinjiangjie reach, terrace, drainage evolution