- Open Access
Variable shape of magnetic hysteresis loops in the Chinese loess-paleosol sequence
Earth, Planets and Space volume 50, pages9–14(1998)
Shape of magnetic hysteresis loops of the Chinese loess-paleosol sequence is variable with low-field susceptibility and is weakly constricted in samples with intermediate susceptibility (~1.0 × 10−6 m3/kg). The analyses of the hysteresis loops show that both low- (ferrimagnetic) and high-coercivity (antiferromagnetic) components are present and the ferrimagnetic component dominate the magnetic characteristics. The ratio of ferrimagnetic over antiferromagnetic minerals (S ratio) and the superparamagnetic fraction increase with increasing susceptibility. Neither simple two-component mixtures of ferrimagnetic and antiferromagnetic minerals nor of single-domain and superparamagnetic grains fully explain the constricted hysteresis loops. We interpret the variation of the loop shape with susceptibility in the following way. When the ratio of the ferrimagnetic to antiferromagnetic contribution is relatively low (low susceptibility), the broad loop is controlled by lithogenic ferrimagnetic and antiferromagnetic minerals. For samples with intermediate susceptibility values, constricted shape originates from an addition of a broad loop from the lithogenic fraction and a narrow loop from a pedogenic fraction with high superparamagnetic content. Then with further susceptibility increase, the constricted shape almost disappears and the loop is dominated by the pedogenic fraction. The variation of hysteresis loop shape with susceptibility can be a useful indicator of the degree of pedogenesis for loess-paleosol samples.
Banerjee, S., C. P. Hunt, and X.-M. Liu, Separation of local signals from the regional paleomonsoon record of the Chinese Loess Plateau: A rock magnetic approach, Geophys. Res. Lett., 20, 843–846, 1993.
Becker, J. J., Surface effects on hysteresis loop shapes in high-coercive-force crystallized amorphous alloys, IEEE Trans. Magn., MAG-18, 1451–1453, 1982.
Bloemendal, J., B. Lamb, and J. W. King, Paleoenvironmental implica-tions of rock-magnetic properties of late Quaternary sediment cores from the eastern equatorial Atlantic, Paleocenography, 3, 61–87, 1988.
Borradaile, G. J., N. Chow, and T. Werner, Magnetic hysteresis of limestones: Facies control?, Phys. Earth Planet. Inter., 76, 241–252, 1993.
Day, R., M. Fuller, and V. A. Schmidt, Hysteresis properties of titanomagnetites: grain-size and compositional dependence, Phys. Earth Planet. Inter., 13, 260–267, 1977.
Evans, M. E. and F. Heller, Magnetic enhancement and palaeoclimate: Study of a loess/paleosol couplet across the Loess Plateau of China, Geophys. J. Int., 117, 257–264, 1994.
Eyre, J. K. and D. P. E. Dickson, Mössbauer spectroscopy analysis of iron-containing minerals in the Chinese loess, J. Geophys. Res., 100, 17925–17930, 1995.
Eyre, J. K. and J. Shaw, Magnetic enhancement of Chinese loess-the role of of γFe2O3?,, Geophys. J. Int., 117, 265–271, 1994.
Fine, P., K. L. Verosub, and M. J. Singer, Pedogenic and lithogenic contributions to the magnetic susceptibility record of the Chinese loess/paleosol sequence, Geophys. J. Int., 122, 97–107, 1995.
Flanders, P. J., An alternating gradient force magnetometer, J. Appl. Phys., 63, 3940–3945, 1988.
Heller, F. and M. E. Evans, Loess magnetism, Rev. Geophys., 33, 211–240, 1995.
Heller, F. and T. Liu, Magnetism of Chinese loess deposits, Geophys. J. R. astr. Soc., 77, 125–141, 1984.
Heller, F. and T. Liu, Paleoclimatic and sedimentary history from mag-netic susceptibility of loess in China, Geophys. Res. Lett., 13, 1169–1172, 1986.
Heller, F., X. Liu, T. Liu, and T. Xu, Magnetic susceptibility of loess in China, Earth Planet. Sci. Lett., 103, 301–310, 1991.
Hunt, C. P., S. K. Banerjee, J. Han, P. A. Solheid, E. Oches, W. Sun, and T.-S. Liu, Rock-magnetic proxies of climate changes in the loess-palaeosol sequences of the western Loess Plateau of China, Geophys. J. Int., 123, 232–244, 1995.
Jackson, M., Diagenetic sources of stable remanence in remagnetized carbonates: A rock magnetic study, J. Geophys. Res., 95, 2753–2761, 1990.
Kukla, G., F. Heller, L. X. Ming, X. T. Chun, T. S. Liu, and Z. S. An, Pleistocene climates in China dated by magnetic susceptibility, Geology, 16, 811–814, 1988.
Liu, X., J. Show, T. Liu, F. Heller, and B. Yuan, Magnetic mineralogy of Chinese loess and its significance, Geophys. J. Int., 108, 301–308, 1992.
Lowrie, W., Identification of ferromagnetic minerals in a rock by coer-civity and unblocking temperature properties, Geophys. Res. Lett., 17, 159–162, 1990.
Maher, B. A. and R. Thompson, Mineral magnetic record of the Chinese loess and paleosols, Geology, 19, 3–6, 1991.
Maher, B. A. and R. Thompson, Paleoclimatic significance of the mineral magnetic record of the Chinese loess and paleosols, Quat. Res., 37, 155–170, 1992.
Muttoni, G., “Wasp-waisted” hysteresis loops from a pyrrhotite and magnetite-bearing remagnetized Triassic limestone, Geophys. Res. Lett., 22, 3167–3170, 1995.
Pick, T. and L. Tauxe, Characteristics of magnetite in submarine basaltic glass, Geophys. J. Int., 119, 116–128, 1994.
Roberts, A. P., Y. Cui, and K. L. Verosub, Wasp-waisted hysteresis loops: Mineral magnetic characteristics and discrimination of components in mixed magnetic system, J. Geophys. Res., 100, 17909–17924, 1995.
Rolph, T. C., J. Shaw, E. Derbyshire, and J. T. Wang, The magnetic mineralogy of a loess section near Lanzhou, China, in The Dynamics and Environmental Context of Aeolian Sedimentary Systems, edited by K. Pye, pp. 311–323, Geological Society, London, 1993.
Sasajima, S. and Y. Y. Wang, The Recent Research on Loess in China, 242 pp., Kyoto Univ. and Northwest Univ., 1984.
Sun, W., S. K. Banerjee, and C. P. Hunt, The role of maghemite in the enhancement of magnetic signal in the Chinese loess-paleosol se-quence: An extensive rock magnetic study combined with citrate-bicarbonate-dithionite treatment, Earth Planet. Sci. Lett., 133, 493–505, 1995.
Tauxe, L., T. A. T. Mullender, and T. Pick, Potbellies, wasp-waists, and superparamagnetism in magnetic hysteresis, J. Geophys. Res., 101, 571–584, 1996.
Torii, M., L. Y. Yue, A. Hayashida, K. Maenaka, T. Yokoyama, Y. Y. Wang, and S. Sasajima, Natural remanent magnetization of loess/paleosol deposits in Luochuan area, in The Recent Research on Loess in China, edited by S. Sasajima and Y. Y. Wang, pp. 32–41, Kyoto Univ. and Northwest Univ., 1984.
Vandenberghe, R. E., E. de Grave, J. J. Hus, and J. Han, Characterization of Chinese loess and associated palaeosol by Mössbauer spectroscopy, Hyp. Interac., 70, 977–980, 1992.
Verosub, K. L., P. Fine, M. J. Singer, and J. TenPas, Pedogenesis and paleoclimate: Interpretation of the magnetic susceptibility record of Chinese loess-paleosol sequences, Geology, 21, 1011–1014, 1993.
Wasilewski, P. J., Magnetic hysteresis in natural materials, Earth Planet. Sci. Lett., 20, 67–72, 1973.
Zhou, L. P., F. Oldfield, A. G. Wintle, S. G. Robinson, and J. T. Wang, Partly pedogenic origin of magnetic variations in Chinese loess, Nature, 346, 737–739, 1990.
About this article
Cite this article
Fukuma, K., Torii, M. Variable shape of magnetic hysteresis loops in the Chinese loess-paleosol sequence. Earth Planet Sp 50, 9–14 (1998). https://doi.org/10.1186/BF03352081
- Hysteresis Loop
- Magnetic Hysteresis Loop
- Isothermal Remanent Magnetization
- Chinese Loess Plateau
- Thermal Demagnetization