The data generated from palaeoflood hydrology will facilitate an appropriate assessment of these flood events and the regional response of the hydrological system to global climatic change at a long time scale.Palaeoflood slackwater deposit(SWD)is a major evidence used for inference about hydrological parameters of the past flood events.Field investigation was carried out in Shaanxi province along the middle reaches of the Yellow River.A set of 3 layers of palaeoflood SWD at the Liulintan(LLT)site was sampled and investigated in detail.According to the OSL dating results,3 palaeoflood events respectively were determined to be in 11 800 to 11 000a B.P.,10 800to 10 200aB.P.,and 10 600to 9 600aB.P.Analysis of the magnetic susceptibility,ignition loss,grain-size distribution,chemical element and scanning electron microscope results indicated that these SWD were generated through the deposition of suspended sediments under high water level hesitation environment,belonging to the typical palaeoflood slackwater deposit.The magnetic susceptibility and losson- ignition of the slackwater deposits were low because they were newly deposited and unaffected by weathering and pedogenesis.The shapes of particle-size distribution curves of the 3layers of slackwater deposits were high and thin(single peak),showing the good sorting characteristics of SWD.According to the analysis of the scanning electron microscope,3layers of SWD belonged to river sand and the L0of Pianguan county belonged to typical loess-aeolian silt sand.Different levels of sediment recorded the different palaeoflood events,which reflected the differences in hydrodynamic size and material sources.The results of grain size and chemical element analysis indicated that 3layers of SWD belonged to fine silt sand and were sourced from the suspended sediment of floodwater of main stream of Yellow River.Among these sediments,SWD1was different from others in the contents of major elements and heavy metal elements,but was similar with the sediment matter formed by the corrosion and transportation of the rainstorm and flood of the Kuye River,which flowed through the desert of Maowusu.The study can provide reference for future identification of palaeoflood slackwater deposits and their sources.