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亚热带红土沉积物物源并不像北方黄土研究那么深入,其成因、来源等一直存在争论,不同类型的沉积物有着不同的物源说。通过分析对亚热带沉积物的稀土元素含量、特征值、配分模式分析,得出:亚热带不同区域的加积型红土,其物质来源不同;加积红土层有明显的分异,同一剖面中的不同沉积层,其沉积环境可能发生了变化;均质红土部分上与北方黄土特征相似,网纹红土在某种程度上也与黄土接近,推测可能均与北方黄土存在一定的物质联系,是北方风尘、地区河湖沉积以及风化壳的高度混合体,其混合程度不同;黄棕色土与下蜀黄土表现出较一致的特征,相对于北方黄土,他们更加接近长江河漫滩沉积物,长江漫滩堆积物可能主导了其物质来源,而黄土对其的影响相对较小。长江河漫滩沉积可能对位于长江河谷附近的第四纪加积红土有较为重要的影响,而随着距离河谷距离的增加,北方风尘和区域各类沉积对物源的贡献增大。
The sources of subtropical red earth sediments are not as deep as the northern loess studies. The causes and sources have been debated. Different types of sediments have different sources. By analyzing the contents of rare earth elements in subtropical sediments, the eigenvalues and the patterns of distribution patterns, it is concluded that the accretion type laterites in different subtropical regions have different sources of their materials; obvious redistribution of accretion red beds and differences in the same section Sedimentary layer, the sedimentary environment may have changed; homogeneous laterite part with northern loess features similar to reticulate laterite to a certain extent with the loess, suggesting that there may be some northern northern loess there is a material connection is the northern dust , The mixture of river and lake sediments and weathered crusts in different regions have different degrees of mixing. Yellow-brown soil and Xiashu loess show more consistent features than the northern loess, which are closer to the floodplain sediments of the Yangtze River, Probably dominates its material source, while loess has a relatively small impact on it. The sedimentation of the Yangtze River floodplain may have a more important influence on the Quaternary accretionary laterite located in the vicinity of the Yangtze River valley. As the distance from the river valley increases, the contribution of the northern dust and various sediments to the provenance increases.