Chemical Weather ing of the Milanggouwan Paleosols in the Salawusu River Valley and Their Paleoclimatic Implication during the Last Interglacial Period
萨拉乌苏河流域末次间冰期 古土壤化学风化与古气候

There are five layers of paleosols in Milanggouwan section in Salawusu River valley of Inner Mongolia during the last interglacial period. We have observed the morphological features of these paleosols and analyzed their grain-size,surface textural features and chemical weathering. The results showed that: (1) These paleosols have some morphological features just like the recent cinnamon soils in North China. (2) They are similar to the recent cinnamon soils that have higher clay contents in the middle part than in the other parts of the soil and SiO2 solution and precipitation can be observed on the surface of the quartz grain,indicating that chemical weathering and pedogenic process have taken place. (3) On the basis of CaO/MgO,K2O/Na2O,Al2O3/Na2O,MnO/Al2O3,CIA and A-CN-K diagram,the comparison results show that the intensity of chemical weathering in paleosols is very similar to the recent cinnamon soils in North China. (4) Using the regression equation of CIA,the values of annual temperature and precipitation of those paleosols can be calculated respectively,and with those values,it is easy to ascertain that the climate conditions are similar to that of North China.