Magnetic Susceptibility and Influencing Factors of Loess From Bole,Xinjiang Province

Bole is a major area with loess sediments in Xinjiang Province.On the basis of a 11 m loess section from bole,a series of indices consisting of magnetic susceptibility,grain size,TOC and CaCO3 in the laboratory.And the results show that the average value of the magnetic susceptibility is far below than that of typical loess on loess plateau,the changing process is also different from that of the typical loess on loess plateau.Coarse silt(63-10 μm) is the dominant component of the section,and there are only a small amount of clay(5 μm),silt(63 μm) and fine silt(5-10 μm) in the section.There is a negative correlation between clay,fine silt and magnetic susceptibility.Clay and fine silt contain little magnetic minerals,so their impacts on magnetic susceptibility is limit,while the contribution of sand is relatively large;The section carries a small quantity of TOC,so TOC makes only a small contribution for magnetic susceptibility;The correlation between magnetic susceptibility and CaCO3 is weak.Thus,the factors influencing magnetic susceptibility in this area are very complex.More climatic indicators in combination with magnetic susceptibility are needed to restore the ancient climate and paleo-environment of the area.And then we can carry out multi-index analysis and synthesis to get more reliable and accurate explanations.