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A detailed stratigraphic division is made in the late Pleistocene loess formation of the central Loess Plateau of China bv the studv of newly found Q_3 loess sectioas.mee climatic cycles,i.e.128;000.90,000 yr B.P.,90,000.50,000 yr B.P.,and 50,000.10,500 vr B.P.,each with a duration Of 40,000years,are established in the area.These are represented by three alternations of aeolian loesses and paleosols,i.e.S_1,L_(1-3);S_(02),L_(1-2);and S_(01),L_(1-1) on the sections,in which chemical composition,magnetic susceptibility,pedogenesis,and the fossil pollen community vary remarkablv.Meanwhile,the first climatic cycle conhains two subcycles,each with a duration of 20,000 vears.Therefore,it reveals that the process of late Pleistocene climatic changes recorded bv Chinese loess is almost the same as that recorded bv the deep.sea sediments and the Antarctic ice sheet.
A detailed stratigraphic division is made in the late Pleistocene loess formation of the central Loess Plateau of China bv the studv of newly found Q_3 loess sectioas. Me climatic cycles, ie128; 000.90,000 yr BP, 90,000.50,000 yr BP, and 50,000.10 , 500 vr BP, each with a duration of 40,000 years, are established in the area. These are represented by three alternations of aeolian loesses and paleosols, ieS_1, L_ (1-3); S_ (02), L_ (1- 2); and S_ (01), L_ (1-1) on the sections, in which chemical composition, magnetic susceptibility, pedogenesis, and the fossil pollen community vary remarkablv.Meanwhile, the first climatic cycle conhains two subcycles, each with a duration of 20,000 vears.Therefore, it reveals that the process of late Pleistocene climatic changes recorded bv Chinese loess is almost the same as as recorded bv the deep .sea sediments and the Antarctic ice sheet.