Magnetic property of loess strata recorded by Kansu profile in Tianshan Mountains
Jia JIA, XianBin LIU, DunSheng XIA, HaiTao WEI, Bo WANG
1 Key Laboratory of West China’s Environmental Systems (Ministry of Education), College of Earth Sciences and Environments , Lanzhou University, Lanzhou 730000, China; 2 Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
Magnetic property of loess strata recorded by Kansu profile in Tianshan Mountains
Jia JIA, XianBin LIU, DunSheng XIA, HaiTao WEI, Bo WANG
1 Key Laboratory of West China’s Environmental Systems (Ministry of Education), College of Earth Sciences and Environments , Lanzhou University, Lanzhou 730000, China; 2 Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
摘要 Kansu (KS) profile is located in the east of Yili basin, western Xinjiang, where typical loess sediments are distributed. The magnetic parameters (such as IRM, SIRM SOFT, and M) and grain size in the KS profile were analyzed in the study. The results showed that the magnetic property of KS loess is dominated by ferrimagnetic minerals, such as magnetite and maghemite. Antiferromagnetic and superparamagnetic minerals also exist in the profile, but had less impact on magnetic susceptibility. Compared with the typical loess sediments of the central Loess Plateau in China, the strata of Kansu profile contained more magnetic minerals and hard magnetic minerals. The analysis of grain size for magnetic minerals indicated that the properties of loess and paleosol were respectively dominated by PSD/MD and coarse SSD magnetite. The research found that the contents of magnetic minerals in loess and paleosol sequences in Kansu profile were similar, but the proportion of fine grained magnetite and soft magnetic minerals were varying, which implies a positive relationship between the value of magnetic susceptibility and intensity of pedogenesis.
Abstract: Kansu (KS) profile is located in the east of Yili basin, western Xinjiang, where typical loess sediments are distributed. The magnetic parameters (such as IRM, SIRM SOFT, and M) and grain size in the KS profile were analyzed in the study. The results showed that the magnetic property of KS loess is dominated by ferrimagnetic minerals, such as magnetite and maghemite. Antiferromagnetic and superparamagnetic minerals also exist in the profile, but had less impact on magnetic susceptibility. Compared with the typical loess sediments of the central Loess Plateau in China, the strata of Kansu profile contained more magnetic minerals and hard magnetic minerals. The analysis of grain size for magnetic minerals indicated that the properties of loess and paleosol were respectively dominated by PSD/MD and coarse SSD magnetite. The research found that the contents of magnetic minerals in loess and paleosol sequences in Kansu profile were similar, but the proportion of fine grained magnetite and soft magnetic minerals were varying, which implies a positive relationship between the value of magnetic susceptibility and intensity of pedogenesis.
基金资助: National 973 Project (2009CB421308); Natural Science Foundation of China (40871080 and 90502008)
通讯作者:
DunSheng XIA
E-mail: dsxia@lzu.edu.cn
引用本文:
Jia JIA, XianBin LIU, DunSheng XIA, HaiTao WEI, Bo WANG. Magnetic property of loess strata recorded by Kansu profile in Tianshan Mountains[J]. 干旱区科学, 10.3724/SP.J.1227.2011.00191.
Jia JIA, XianBin LIU, DunSheng XIA, HaiTao WEI, Bo WANG. Magnetic property of loess strata recorded by Kansu profile in Tianshan Mountains. Journal of Arid Land, 2011, 3(3): 191-198.
