A wind-tunnel study on the sorting effects of wind erosion towards the geochemistry and the particle size of the surface samples from the Horqin sandy land

Samples from the Horqin sandy land were exposed to a series of wind velocities and the sink particles were collected at the end of the diffusion section of a wind tunnel. The resulting grain size was coarser than the original one, and the original samples showed lower average content of the SiO₂ and higher average content of Al₂O₃, Fe₂O₃, MgO, CaO, Na₂O, and K₂O than the collected samples did. Comparing with other dust source area in China, the Horqin sandy land had higher content of the Zr, Ba, SiO₂, Al₂O₃ and K₂O. Compared with the average upper continental crust (UCC) composition, surface samples were rich in the content of the Y, Zr, Nb, Ba, La, Nd. Geochemistry characteristics of the fine grain components of the Horqin sandy land differ from those from other dust source regions, because the fine-grained particles in the Horqin sandy land were mostly derived from various local deposits formed in its unique depositional environments controlled by several tectonic activities.