【摘 要】
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Samples from the Horqin sandy land were exposed to a series of wind velocities, and sink particles were collected at the end of the diffusion section of a wind tunnel. Grain sizes of collected samples show great variation because of the granu-larity diffe
【机 构】
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Key Laboratory of Desert and Desertification,Northwest Institute of Eco-Environment and Resources,Ch
论文部分内容阅读
Samples from the Horqin sandy land were exposed to a series of wind velocities, and sink particles were collected at the end of the diffusion section of a wind tunnel. Grain sizes of collected samples show great variation because of the granu-larity difference of the surface samples. The original samples show lower average content of SiO2 and higher average con-tent of Al2O3, Fe2O3, MgO, CaO, Na2O, and K2O than collected samples. Compared with other dust source areas in China, the Horqin sandy land had higher content of Zr, Ba, SiO2, Al2O3 and K2O. Compared with the average upper continental crust (UCC) composition, surface samples were rich in the content of Y, Zr, Nb, Ba, La, Nd. Geochemistry characteristics of fine grain components of the Horqin sandy land differ from those from other dust source regions, because fine-grained particles in the Horqin sandy land were mostly derived from various local deposits formed in its unique depositional envi-ronments influenced by several tectonic activities.
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