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在六盘山以西广泛分布着一套第三纪红色土状沉积，对这套沉积的成因及性质还没有系统的研究。本文对陇西红土磁学性质的研究发现，该地红土的剩磁载体由主到次依次为磁铁矿、磁赤铁矿和赤铁矿，赤铁矿对剩磁有比较显著的贡献；特征剩磁载体主要是磁铁矿，一些古土壤中的赤铁矿也携带了部分特征剩磁，磁赤铁矿的存在不影响特征剩磁的稳定性。与六盘山以东宝鸡红土最显著的差异是陇西红土中的赤铁矿对磁学性质有明显的影响。与第四纪黄土－古土壤序列的热磁学性质的差异在于陇西红土在高温下仅产生少量或不产生强磁性矿物。这可能暗示着红土中含铁硅酸盐和粘土等矿物（可能在高温下产生磁铁矿）处于与黄土－古土壤的相应矿物不同的演化阶段。
A set of Tertiary red earth-like sediments are widely distributed to the west of Liupan Mountain. There is no systematic study on the causes and properties of the sediments. The study on the magnetism of Longxi clay shows that the remanence of laterite from the main to the next is magnetite, maghemite and hematite, and the hematite has a significant contribution to the remanence. The remanent magnetic carrier is mainly magnetite. Some hematite in ancient soil also carry some residual magnetization. The existence of maghemite does not affect the stability of the characteristic residual magnetism. The most significant difference from the Baoji clay in the east of Liupan Mountain is that the hematite in the Longxi red clay has obvious influence on the magnetic properties. Compared with the thermomagnetic properties of Quaternary loess-paleosol sequence, the Longxi laterites produced only little or no strong magnetic minerals at high temperature. This may suggest that minerals such as iron silicates and clays in the laterites, which may produce magnetite at high temperatures, are in a different evolutionary stage than the corresponding minerals in loess-paleosol.