Fractal of the Gobi surface sediment components and its variability characteristics

The surface sediment components of the Gobi are extremely complex, and the content has a "multimodal" dis-tribution. Additionally, the gravel content, cover degree, and gravel distribution have shown significant spatial heterogeneity. Traditional fractal theory has limitations in the multimodal component fractal calculation, and the physical meaning remains unclear. In this study, we modified the traditional fractal calculation method according to a segmented weighted averaging method and quantitatively expressed spatial heterogeneity fea-tures, such as the Gobi surface, using the fractal dimension and its variation parameters. The results showed that the surface sediment component of Gobi was fractal, the fractal dimensions were between 2.23 and 2.84, and the average value was 2.56. Both the sediment component content and the granularity composition distribution structure (unimodal, bimodal, and multimodal state) had a significant influence on the fractal dimension values. The fractal dimensions of the medium-gravel Gobi sediment had a large local variability but less spatial vari-ability. The fractal dimension degree of local variation of the sandy gravel Gobi sediment was low, but had a large range of spatial variation and a large spatial variability. The local variation and spatial variability of fine -gravel Gobi sediment were both small.