PROGRESS IN GEOGRAPHY ›› 2010, Vol. 29 ›› Issue (7): 840-846.doi: 10.11820/dlkxjz.2010.07.010

• Original Articles • Previous Articles     Next Articles

Palaeo-Hydrologrcal Studies of the Holocene Extreme Floods in the Tianshui Gorges of the Weihe River

ZHU Xiangfeng1, HUANG Chunchang1,2, PANG Jiangli1, ZHA Xiaochun1   

  1. 1. College of Tourism and Environmental Sciences, Shaanxi Normal University, Xi'an 710062, China|
    2. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth and Environment Research, CAS, Xi'an 710075, China
  • Received:2009-09-01 Revised:2010-01-01 Online:2010-07-25 Published:2010-07-25


Palaeoflood hydrological studies were carried out at the upper reach gorges of the Weihe River. Palaeoflood slackwater deposits were found at the DJP site in the Tianshui gorges of the mainstream of the river. Analysis of the grain-size distribution indicates that these SWD consist of silts and clayey silts, sourced from the suspended sediment load of the floodwater. The low magnetic susceptibility indicates they are fresh deposits without weathering and pedogenic alteration. Stratigraphic correlation with the SWD discovered downstream at the Guchuanzhen site of the Weihe River shows that these extreme floods occurred between 3200-3000 a BP at the end of the mid-Holocene climatic optimum. The reconstructed peak discharges of the palaeofloods range from 23,460 m3/s to 25,480 m3/s which are much larger than gauged floods. These results were further tested and proved to be reliable with reconstruction of the modern floods at the same reach. This research is of great importance for hydrological engneering and flood mitigation. And it is also very important for the establishment of the relationships between extreme flood events and global climate change.

Key words: Holocene, hydrology, palaeoflood, slackwater deposits, Weihe River