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通过地貌和典型剖面的考察和研究，发现安徽宣州地区黄棕色土的层序位于第四纪红土层之上。用ESR测年法测得黄棕色土年龄约为80kaB．P.，红土年龄约为240kaB．P.。对这两种成土母质的各项理化性状和磁化率指标进行比较研究，发现黄棕色土受风化作用的程度不如第四纪红土。这表明该地区24万年前的湿热气候至8万年左右开始转凉，不适于红土的形成。现今该地区出露的红土都是中更新时期古气候的产物，而黄棕色土则是与近代气候环境更相接近的一种沉积物。
Through the investigation and study of landforms and typical sections, it is found that the sequence of yellow-brown soil in Xuanzhou area of Anhui Province is located above the Quaternary red earth. The yellow-brown soil, measured by ESR dating, has an age of about 80kaB. P., laterite age is about 240kaB. P .. The physical and chemical properties and magnetic susceptibility indexes of the two parent materials were compared and found that the weathering of yellow-brown soil was not as good as that of Quaternary laterite. This shows that the hot and humid climate of 240,000 years ago in the area started to cool off around 80,000 years and was not suitable for the formation of laterite. Nowadays, the red clay exposed in the area is the product of the paleoclimate of the Middle Pleistocene, while the yellow-brown soil is a sediment closer to modern climate and environment.