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选取阿西克剖面作为研究对象,对伊犁地区末次间冰期以来的沉积的黄土地层的磁学特征进行分析。结果发现,伊犁地区黄土地层的磁性矿物有磁铁矿、磁赤铁矿、赤铁矿、针铁矿,磁学性质受亚铁磁性的磁铁矿(和磁赤铁矿)控制;MD和PSD是地层中亚铁磁性矿物的主要磁畤状态,随着成壤强度增加,地层中的SP和SD颗粒相对含量逐渐增加;亚铁磁性矿物含量与地层并不完全对应。对磁学参数控制机制的分析表明,本剖面磁学性质受控因素比较复杂,磁性矿物含量主要受控于物源的磁学性质,成壤作用对地层中细粒磁性矿物含量具有很大影响,还原作用可能对底部古土壤层的磁学性质造成一定影响,但对整个剖面的磁学性质影响相对较小。
The Asik section is selected as the research object to analyze the magnetic characteristics of the loess stratum deposited since the last interglacial period in Ili region. The results show that the magnetite, maghemite, hematite and goethite in loess stratum in Yili area are controlled by magnetite (and maghemite) whose magnetic properties are ferrimagnetism. MD and PSD is the main magnetic state of ferrimagnetic minerals in the strata. With the increase of soil strength, the relative content of SP and SD particles in the strata gradually increases. The content of ferrimagnetic minerals does not correspond exactly with the strata. The analysis of the control mechanism of the magnetic parameters shows that the controlled factors of the magnetic properties of this section are quite complicated. The content of magnetic minerals is mainly controlled by the magnetic properties of the provenance. The pedogenesis has a great influence on the content of fine-grained magnetic minerals in the formation , The reduction may have an impact on the magnetic properties of the bottom palaeosol, but the magnetic properties of the entire section have a relatively small impact.