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Remanence Characteristics of Different Magnetic Grain Size Categories at Xifeng, Central Chinese Loess Plateau

Published online by Cambridge University Press:  20 January 2017

Xiuming Liu
Affiliation:
Department of Geography, University of Liverpool, Liverpool L69 3BX, UK
Tim Rolph
Affiliation:
Geomagnetism Laboratory, University of Liverpool, Liverpool L69 3BX, UK
Jan Bloemendal
Affiliation:
Department of Geography, University of Liverpool, Liverpool L69 3BX, UK
John Shaw
Affiliation:
Geomagnetism Laboratory, University of Liverpool, Liverpool L69 3BX, UK
Tungsheng Liu
Affiliation:
Institute of Geology, Chinese Academy of Sciences, P.O. Box 634, Beijing 100029, China

Abstract

Utilizing the thermal unblocking of low-temperature remanent magnetization in superparamagnetic (SP) ferrimagnets and the low-temperature demagnetization of multidomain (MD) magnetite remanences, the relative proportions of SP, MD, and singledomain (SD and SD-like) ferrimagnets are estimated in the topmost part of a loess section at Xifeng, China, which covers about the past 130,000 yr. SP ferrimagnets are commonly regarded as pedogenic (authigenic) products while the MD component is believed to have a detrital origin. These measurements, therefore, provide new data which improve our understanding of the characteristics and distribution of the different magnetic grain-size fractions present in loess and soils. In particular, our measurements indicate a larger MD fraction in soil than in loess, a result which indicates that although enhancement of the SP ferrimagnet fraction dominates the increased low-field magnetic susceptibility of paleosols, an enhancement of the MD fraction, probably through leaching, also plays an important role during pedogenesis.

Type
Research Article
Copyright
University of Washington

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References

Baneijee, S. K.., Hunt, C. P., and Liu, X. M. (1993). Separation of local signals from regional paleomonsoon record of the Chinese loess plateau: A rock-magnetism approach. Geophysical Research Letters 20, 843846.Google Scholar
Dunlop, D. J. (1973). Superparamagnetic and single-domain threshold sizes in magnetite. Journal of Geophysical Research 78, 17801793.Google Scholar
Guo, Z. T. Fedoroff, N. An, Z. S., and Liu, T. S. (1993). Interglacial dustfall and origin of iron oxides-hydroxides in the paleosols of the Xifeng loess section, China. Scfentia Geohgica Sinica 2, 91100.Google Scholar
Heller, F. Liu, X. M. Liu, T. S., and Xu, T. C. (1991). Magnetic susceptibility of loess in China. Earth and Planetary Science Letters 103, 301310.CrossRefGoogle Scholar
Kukla, J. G. and An, Z. S. (1989). Loess stratigraphy in central China. Palaeogeography, Palaeoclimatology, Palaeoecology 72, 203225.Google Scholar
Liu, X. M. Shaw, J. Liu, T. S. Heller, F., and Yuan, B. Y. (1992). Magnetic mineralogy of Chinese loess and Us significance. Geophysical Journal International 108, 301308.CrossRefGoogle Scholar
Liu, X. M. Heller, F. Liu, T. S. Xu, T. C., and Shaw, J. (1993). Magnetic susceptibility analysis of Chinese loess. Journal of the Geological Society 150, 583588.Google Scholar
Maher, B. A., and Taylor, R. M. (1988). Formation of ujtrafine-grained magnetite in soils. Nature 336, 368370.Google Scholar
Maher, B. A., and Thompson, R. (1992). Paleoclimatic significance of the mineral magnetic record of the Chinese loess and paleosols. Quaternary Research 37, 155170.Google Scholar
Ozdemir, 0. Dunlop, D. J., and Moskowitz, B. M. (1993). The effect of oxidation on the verwey transition in the magnetite. Geophysical Research Letters 20, 16711674.Google Scholar
Rolph, T. C. Shaw, J. Derbyshire, E., and Wang, J. T. (1993). The magnetic mineralogy of a loess section near Lanzhou, China. In “The Dynamics and Environmental Context of Aeolian Sedimentary Systems” (Pye, K., Ed.), Geological Society Special Publication 72, pp. 311323.Google Scholar
Thompson, R., and Oldfield, F. (1986). Environmental magnetism. Allen and Unwin, London.Google Scholar
Verosub, K. L. Fine, P. Singer, M. J., and TenPas, J. (1993). Pedogenesis and palaeoclimate: Interpretation of magnetic susceptibility of Chinese loess-palaeosol sequences. Geology 21, 10111014.Google Scholar
Zhou, L. P. Oldfield, F. Wintle, A. G. Robinson, S. G., and Wang, J. T. (1990). Partly pedogenic origin of magnetic variations in Chinese loess. Nature 346, 737739.Google Scholar