HR: 1340h
AN: GP43B-1220    [Abstracts]
TI: Enhancement Mechanisms of Magnetic Susceptibility in the Chinese Red-Clay Sequence
AU: * Nie, J
EM: junsheng@gso.uri.edu
AF: URI Graduate School of Oceanography, South Ferry Road, Narragansett, RI 02882, United States
AU: * Nie, J
EM: junsheng@gso.uri.edu
AF: Institute of Tibetan Plateau Research, Chinese Academy of Science, P. O. Box 2871, Shuangqing Road., Beijing, 100085, China
AU: * Nie, J
EM: junsheng@gso.uri.edu
AF: Lanzhou University, Tianshui Road, Lanzhou, 730000, China
AU: King, J
EM: jking@gso.uri.edu
AF: URI Graduate School of Oceanography, South Ferry Road, Narragansett, RI 02882, United States
AU: Fang, X
EM: fangxm@lzu.edu.cn
AF: Institute of Tibetan Plateau Research, Chinese Academy of Science, P. O. Box 2871, Shuangqing Road., Beijing, 100085, China
AU: Fang, X
EM: fangxm@lzu.edu.cn
AF: Lanzhou University, Tianshui Road, Lanzhou, 730000, China
AB: Little is known about the mechanisms of magnetic susceptibility (÷) enhancement for the Red-Clay sequence on the Chinese Loess Plateau (CLP), in comparison to the overlying loess-paleosol sequence. Here we present a rock magnetic study of the Red-Clay sediments from the central CLP. Our results show that frequency dependence of ÷ (÷fd = ÷lf – ÷hf , where ÷lf and ÷hf are ÷ measured at 470 Hz and 4700 Hz, respectively), ÷lf, and susceptibility of anhysteretic-remanent-magnetization (÷ARM) are linearly correlated within the Red-Clay sequence. This linear correlation indicates that the pedogenic magnetic minerals of the Red-Clay have a rather uniform grain size distribution as in the loess-paleosol sequence, and the grain size is independent of the degree of pedogenesis. Nevertheless, Red-Clay sediments are slightly more enriched in superparamagnetic magnetic particles than the overlying loess-paleosol sediments as indicated by the higher slope of the regression line between ÷fd and ÷lf.
DE: 1512 Environmental magnetism
DE: 1519 Magnetic mineralogy and petrology
DE: 1540 Rock and mineral magnetism
DE: 1637 Regional climate change
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2007 Fall Meeting