The Holocene sediment profile was surveyed in detail and sampled systematically at the Liaowadian site on the first river terrace in the upper Hanjiang valley.Its sedimentological and hydrological characteristics were observed in the field.Particle-size distribution

magnetic susceptibility and loss-on-ignition were analyzed in laboratory.An integration of the results showed that the palaeoflood slackwater deposits of the profile are very typical

recording an extreme flood event that might occur during A D 100-300 according to stratification comparison.Based on flood level information recovered using sedimentological and palaeo-hydrological methods

the palaeoflood peak discharge could reach 65 420 m3/s.The methods were further validated by the reconstruction of the modern flood event(20110919)

with a very low error less than 1%.