In the famous eolian loess plateau of north China a number of paleosol layers were recognized early.Thirteen layers of buried paleosols can often be found in well preserved late Pleistocene Malan loess and middle Pleistoeene Lishi loess, that deposited during the Brunhes Normal epoeh.Among them,the fifth layer,counting from top to bottom,paleosol in Luoehuan locss section,Shaansi Province,is charaeterized by its greater thickness,red brown colour,and a well developed clay enriched horizons as well as carbonate eoneretions at the bottom.The reversed magnetization observed in samples from the top of soil section records short reversed event during the Brunhes epoch,corresponding to I Biwa reversed event in Japan.Thermolumi-nescence datiilg shows that this unit was formed between 212000-178000 years ago.The Luochuan fifth layer paleosol,with two closely related clay enriched horizons,consists of two thin layers paleosol.Large quantity of illuviation ferri-argillans observed in the soil section show that the elay had been transported and deposited.In addition,results of micropedology and soil magnetization studies,mechanical and chemical analyses prove that the fifth layer poleosol approach burozem type.It is a produet of bioelimatie belt between temperate deciduous-broadleaf forest and dry forest types.As a eonsequenee,the oceurrenee of fifth layer paleosol indicates that the climate in the loess plateau about 0.2 million Y.B.P.,is warmer and wetter than in Holocene at the same place,beeause the nature landscape in Holocene in Luochuan region belongs to steppe type.
安芷生,魏兰英.离石黄土中的第五层古土壤及其古气候的意义[J].土壤学报,1980,17(1):1-10. An Zhi-sheng, Wei Lan-ying. THE FIFTH LAYER PALEOSOL IN THE LISHI LOESS AND THEIR PALEOCLIMATIC SIGNIFICANCE[J]. Acta Pedologica Sinica,1980,17(1):1-10.复制