Grain size distribution, Be-10 content and magnetic susceptibility of micrometer-nanometer loess materials

Abstract

Grain size distribution, 10Be content and magnetic susceptibility of loess particles in the Luochuan section were measured and the results are discussed in terms of fragmentation and fractal theory. The fact that the order of increasing specific surface area of bulk samples from the horizons of S0, L1LL1, L1LL2, S1 and L2 is consistent with the order of successively warmer palaeo-climate may provide a new indicator for palaeo-climatic and palaeo-environmental studies. The values of fractal dimension for the grains of S1 and L2 are 2.80 and 2.76, respectively. Our results also show that the magnetic properties of loess particles depend strongly not only upon particle size but also upon pedogenic characteristics and that 10Be is mainly adsorbed on the surface of ultra-fine particles, independent of pedogenic process.