| This paper reports a loess-paleosol sequence located in Danube River basin, Serbia, which formed at least since the latest part of early Pleistocene, before paleomagnetic B/M boundary. Various magnetic parameters of Serbian V-L1-V-S4loess-paleosol sequence in Titel Loess Plateau have been measured and analyzed, showing a very similar magnetic behavior with that of Chinese loess. There is a general positive relation between magnetic susceptibility (χ) and pedogenesis. The main contributor to χ is the magnetic grains of SP (superparamagnetic) and SD (single domain) magnetic domain, while MD (multi dbmain) is only a small percentage. The difference of χ between loess and paleosoil mainly caused by pedogenesis. The extra fine magnetic minerals increase gradually with soil development (from loess to soil), lead to higher χ. The thermomagnetic curves show that, magnetic minerals in the loess layers are magnetite and maghemite, both playing a major contribution to χ, while in the paleosol layers, mainly are magnetite, and contains almost no or a very small amount of maghemite, implied by a reversible thermomagnetic behave. That indicates that, pedogenic conditions during V-S3and V-S4strong soil development has resulted maghemite no longer stable, but been resolved or converted to other stable phase minerals. Which likely indicate that soil moisture during V-S3and V-S4development has likely exceeded a critical condition of maghemite stability.Analysis of sedimentary granularity also shows that, in the L1-S4loess-paleosol sequence of Titel section, the median diameter (Md) minimum appeared in paleosol S4, this also consistent with the magnetic parameters analysied below, especially the analysis of magnetic particle size. This also provides evidence about what we think paleosol S4have distorted the judgment for climate records. |
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