Palaeoflood events and climate change at the turning time from the Shang to Zhou Dynasty in the Longmen reach of the Yellow River

Abstract

Palaeoflood slackwater deposits (SWD) of the Holocene and paleoflood indicators were interbeddedly found within the cliff riverbanks at Xianghanqiao profile in the Longmen reach of the Yellow River. Paleoflood SWD was identified by a variety of sedimentological criteria during field investigations and laboratory analysis. A set of four SWD records four paleoflood events individually. These slackwater deposits recorded the extraodinary floods happened between 3200-2800 a B.P. on the Yellow River, by using Optically Stimulated Luminescence dating method in combination with pedostratigraphy correlations. This indicated that the extraordinary floods happened during the dynasties from the Shang to the Western Zhou in Chinese history. The flooding peak stages were estimated with the sediment concentration and the depositional depths of the SWD. The estimated results indicated that the paleoflood peak discharges were between 46280 and 48800 m3/s by using HEC-RAS model. The results provided an important basis for this regional flood control and disaster mitigation project, water resource management, and comprehensive treatment of the ecological environment.