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黄土高原地区地表土壤磁化率与气候的温湿程度(温度和降水)呈明显的正相关关系,目前成壤过程中形成的细颗粒软磁性矿物被认为是导致土壤磁化率增加的主要原因,磁化率作为一个夏季风代用指标在该区得到广泛应用.但相对于黄土高原地区比较成熟的岩石磁学研究来说,目前对主要由西风带所控制的塔里木盆地及其周边地区的表土岩石磁学性质的研究还相对较少,对控制该区表土岩石磁学性质的主要原因也还不是十分清楚.为进一步理解不同气候、不同环境条件下土壤磁化率与气候的关系,对塔里木盆地及其南缘49个风尘堆积表土样品进行了详细的岩石磁学和粒度分析.结果表明,研究区表土样品的岩石磁学性质主要由来自源区的粗颗粒软磁性矿物所控制,成壤作用形成的细颗粒磁性矿物对其影响非常有限.其中,沙漠样品的磁化率和饱和等温剩磁都表现为最低值,主要由富含软磁性矿物的颗粒含量较少所造成.亚砂土和黄土样品的磁化率和饱和等温剩磁均高于沙漠样品,且随着海拔的升高有明显减小的趋势,来自源区的粗颗粒软磁性矿物的含量是导致这种变化的主要原因.
The magnetic susceptibility of surface soil in the Loess Plateau is positively correlated with the temperature and humidity (temperature and precipitation) of the climate. The fine-grained soft-magnetic minerals formed during the process of soil-forming are considered to be the main causes of the increase of soil magnetic susceptibility. Magnetization However, compared with the relatively mature rock magnetism study in the Loess Plateau, the surface rock lithology of the Tarim Basin, mainly controlled by the westerlies, The nature of the study is relatively small, the main reason for controlling the rock magnetic properties of the topsoil is not yet clear.For further understanding of the relationship between soil magnetic susceptibility and climate under different climate and environmental conditions, the Tarim Basin and its south The results show that the rock magnetic properties of the topsoil samples in the study area are mainly controlled by the coarse-grained soft-magnetic minerals from the source area, and the formation of fine-grained clay particles Particulate magnetic minerals have very limited influence on them, of which the magnetic susceptibility and saturated isothermal remanence of desert samples are the most Low value is mainly caused by the less content of soft magnetic minerals.The magnetic susceptibility and saturated isothermal remanence of both sandy loess and loess samples are higher than that of desert samples and obviously decrease with the elevation The trend, the content of coarse-grained soft-magnetic minerals from the source zone, is the main reason for this change.