Through field investigation in the upper reaches of the Hanjiang River，palaeoflood slackwater deposit was found in the Gaodianpu-Gouyuanxiang reach of Xunyang county. The results of field observation and measurement of grain-size and magnetic susceptibility indicate that these slackwater deposit are very typical and that they have been deposited by suspended sediment load in the floodwater. By pedo-stratigraphical correlation, the palaeoflood events were dated to between 9 500—8 500 a B.P. and 3 200—2 800 a B.P.，respectively. The flood peak discharges were reconstructed to 43 290~49 130 m3/s. They were checked by the reconstruction of the 2010 extraordinary flood based on the stage indicator and the same hydrological parameters. The 10 000-year time-scale relations between flood peak discharge and occurrence frequency are therefore established. It is very important for flood design in the hydraulic engineering and flood control, and for understanding the response of fluvial system to global climate change.

Hanjiang River; palaeoflood; 10 000-year time-scale; Holocene; slackwater deposits