COMPARATIVE STUDY ON QUATERNARY RED EARTH AND XIASHU LOESS IN PHYSICAL AND CHEMICAL CHARACTERISTICS

As Quaternary sediments, aggradational red earth and Xiashu Loess are frequently seen in the subtropical zone in China. Grain-size, quartz surface characteristics, magnetic susceptibility, and REE of red earth are tested and compared with Xiashu Loess. The results show that, generally, the physical and chemical characteristics of red earth and Xiashu Loess are similar to each other, indicating aeolian characteristics. However, red earth shows stronger weathering properties. At the same section, the bottom-up sedimentary sequence from red earth to Xiashu Loess indicates gradually weak weathering, and a climatic transition from warm-humid to dry-cold during mid-Pleistocene and late Pleistocene. The differences of physical and chemical characteristics among Xiashu formation sediments, deposited in the same epoch but different areas, reflect the latitude effects of paleoenvironmental changes and horizontal zonality.