摘要
Through widespread field survey along the Jinghe River valley,a Holocene loess-soil profile with interbedded flood slackwater deposits(SWD) was found at the YGZ site at the riverbank near the Yangguanzhai village.The comparative study of the geochemical difference between palaeoflood slackwater deposits and the eolian loess and soil showed that:1) the concentrations of major elements Fe2O3,Al2O3.K2O,MgO are higher in the palaeosol(S0) and lower in the loess (L1,Lt,L0); and 2) in a single palaeoflood slackwater deposit (SWD) bed, the sorted deposition in floodwater resulted in a concentration of the coarse fraction and heavy minerals at the bottom of the SWD bed. Thus,Zr,Hf,Ti,Cr,Y and other trace elements show a prominent peak.