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西风区黄土沉积序列的磁化率变化特征比较复杂,磁化率与成壤强度之间的相关性在不同的区域环境中具有一定的差异。选取塔城地区黄土剖面作为研究对象进行较为系统的磁学特征分析。结果显示,塔城剖面的磁性矿物主要为磁铁矿、磁赤铁矿等亚铁磁性矿物,同时含有一定量的反铁磁性矿物和顺磁性矿物,磁畴状态主要是多畴(MD)和假单畴(PSD)。成壤作用影响单畴(SD)颗粒磁性矿物的相对含量,而对超顺磁(SP)颗粒的贡献有限。影响地层磁学性质的因素比较复杂,粒度与磁学参数的变化与区域的气候波动具有一定的对应关系。古土壤中磁性矿物浓度的降低以及钙积现象可能反映了成壤时期温暖干燥的气候条件,磁性矿物浓度的变化在一定程度上或许是对区域相对湿度状况的反映。
The change of magnetic susceptibility of loess sedimentary sequence in the Xifeng area is complicated, and the correlation between magnetic susceptibility and soil-forming intensity has some differences in different regional environments. The loess section in Tacheng is selected as the research object to conduct a systematic analysis of the magnetic characteristics. The results show that the magnetic minerals in Tacheng profile are mainly ferrimagnetic minerals such as magnetite and maghemite, and contain a certain amount of antiferromagnetic minerals and paramagnetic minerals. The magnetic domain states are mainly multidomain (MD) and false Single domain (PSD). Pedogenesis affects the relative content of monodomain (SD) magnetic minerals, while contribution to superparamagnetic (SP) particles is limited. The factors influencing the magnetic properties of the formation are complex, and the changes of the grain size and the magnetic parameters have some corresponding relations with the regional climate fluctuations. The decrease of magnetic minerals and the accumulation of calcium in ancient soils probably reflect the warm and dry climatic conditions in the period of pedogenesis. The change of magnetic mineral concentration may reflect the regional relative humidity to a certain extent.