Fractal characterization of the spatial uniformity of three component stations in China Geomagnetic Survey for 2005.0

The purpose of this research is to investigate the spatial distribution uniformity of three component stations in China Geomagnetic Survey for 2005.0. Based on fractal theory, the fractal analysis is used to describe spatial homogeneity of three component stations. The study region is divided into equal area squares with different scales. The station counts and scales are extracted from the squares and plotted in bi-logarithm coordinates, then a linear fitting to the plotted data is made. The absolute value of the linear slope is just the fractal dimension Df, which can be used as an indicator for evaluating the uniformity. Our study result indicates that, the fractal dimension for whole China mainland, for the region east of 105deg;E and for that west of 105deg;E are different from each other, being 1.748, 1.796 and 1.609, respectively. The fractal dimension, 1.796, for the eastern region, is closer to the embedding dimension E=2 (surface of the Earth) than that of western region, implying that the three component stations distribution of the eastern region is more homogeneous.