Abstract
In order to fully understand the chemical properties of Asian dust particles, especially their transformation and aging processes, it is desirable to investigate the nature of original sands collected at local source areas in China. This study presents the detailed properties of sands collected at four different desert regions (Yinchuan, Wuwei, Dulan, and Yanchi) in China. Most of sands have irregular shape with yellowish coloration, whereas some of them show peculiar colors. The relative size distribution of sands collected at Yinchuan, Wuwei, and Dulan deserts exhibits monomodal with the maximum level between 200 and $300{\mu}$, whereas that of Yanchi desert is formed between 100 and $200{\mu}$. The mass concentration ratio of each element to that of Si (Z/Si) determined by PIXE analysis has a tendency towards higher Z/Si ratios for soil derived elements. It was possible to visually reconstruct the elemental maps on the surface of individual sands by XRF microprobe technique. In addition, the multielemental mass concentration could be quantitatively calculated for numerous spots of desert sands.
