An investigation of rock magnetic properties using the temperature-dependence ofsusceptibility （TDS） and the coercivity of different IRM components was conducted on samples ofthe Malan loess （L1） and the last inte...An investigation of rock magnetic properties using the temperature-dependence ofsusceptibility （TDS） and the coercivity of different IRM components was conducted on samples ofthe Malan loess （L1） and the last interglacial soil （S1） along an E-W transect of the Chinese LoessPlateau. We find that the behavior of the TDS is useful in identifying maghemite （γ-Fe<sub>2</sub>O<sub>3</sub>） in bothloess and paleosol, and that it can be used as a new proxy of the degree of pedogenesis, which isclosely linked to climatic conditions. Based on results from the TDS, we conclude that （1） thedetrital magnetite grains predominate in the L1 unit to the west of Liupan Mts, where theweathering and pedogenetic processes were weakest; （2） a comparable degree of pedogenesisexists in the L1 at the east of the Liupan Mts and the S1 at the west of the Liupan Mts; （3） a higherconcentration of maghemite is found in the S1 unit at the eastern sections, suggesting that the localclimate was warmer and more humid in this interval. In addition, we propose that TDSmeasurements can be used as a rapid means of determining the reliability of the paleomagneticsecular variation （PSV） record in loess/poleoso/sequenees.展开更多
文摘An investigation of rock magnetic properties using the temperature-dependence ofsusceptibility （TDS） and the coercivity of different IRM components was conducted on samples ofthe Malan loess （L1） and the last interglacial soil （S1） along an E-W transect of the Chinese LoessPlateau. We find that the behavior of the TDS is useful in identifying maghemite （γ-Fe<sub>2</sub>O<sub>3</sub>） in bothloess and paleosol, and that it can be used as a new proxy of the degree of pedogenesis, which isclosely linked to climatic conditions. Based on results from the TDS, we conclude that （1） thedetrital magnetite grains predominate in the L1 unit to the west of Liupan Mts, where theweathering and pedogenetic processes were weakest; （2） a comparable degree of pedogenesisexists in the L1 at the east of the Liupan Mts and the S1 at the west of the Liupan Mts; （3） a higherconcentration of maghemite is found in the S1 unit at the eastern sections, suggesting that the localclimate was warmer and more humid in this interval. In addition, we propose that TDSmeasurements can be used as a rapid means of determining the reliability of the paleomagneticsecular variation （PSV） record in loess/poleoso/sequenees.
