| The investigations on the Red Clay,underlying the Loess-Paleosol deposit of the Loess Plateau,have becoming a hot spot in nearly two decades.Although significant progress has been made,there are some key issues to be resolved,for example,the application of proxy climate indicator,the origin and the dynamic mechanism of windy deposit and so on.In this paper,detail investigations were made on the Magnetostratigraphy,Sedimentology and chroma of Red clay section at Shaozhai to the East of LiuPan Mountain in southern Loess Plateau.The main conclusions are presented as following:1.The result of magnetostratigraphy shows that the eolian dust deposition recorded at Shaozhai section had been existed at lest 6.7 MaB.P.ago.The deposition from 6.7 to 5.25 MaB.P.was possibly re-deposited and from 5.25 Ma B.P.is typical winded.2.There is no strict relativity in mathematics between magnetic susceptibility and chroma of ShaoZhai Red Clay section.But they are in good correspondence with each other at a timescale of structure.This shows that both of them have same climatic indicators and the chroma is more sensitive.3.According to magnetic susceptibility and chroma,the summer monsoon may be divided into five stages:it was relatively stronger in 5.25-4.95 MaB.P.and 4.3-3.65 MaB.P., relatively weaker in 4.95-4.3 MaB.P.with a trend of becoming strong.It has a periodical rising and large amplitude monsoon during 3.65-2.75 MaB.P.It was Quaternary period from 2.75MaB.P.to 2.6 MaB.P..The points of 3.65 and 2.75 MaB.P.were the most important in the process of the climatic evolution.4.The average of percent content greater than 32μm of ShaoZhai Red Clay section is about 8.24%.This showed that the winter monsoon was the main force during Pilocene epoch.5.The comparison of magnetic susceptibility,chroma and grain size indicated that the winter and summer monsoon enhanced synchronously on a timescale of structure since 5.25 MaB.P..
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