FRACTAL MEASURE OF THE EARTH’S SURFACE AND ITS SIGNIFICANCE TO GEOTECTONICS

Two-dimensional fractal measurement about the earth’s surface in H ong’an district, Hubei Province, China was carried out by using projective cove ring method in this paper. The results indicate that the earth’s surface area s hows a bifractal relationship between area and scale, which involves a textural fractal at small scale and a structural fractal at large scale, with the average breakpoint being at 3610m, the fractal dimension values ranging generally from 2 to 3 and the textural fractal dimension values being larger than their structu ral counterparts. This demonstrates that the earth’s surface morphology is of t he fractal type, and the fractal value can be used to indicate the complexity of the morphology of the earth’s surface and the intensity of tectonic movement. As a result, the fractal value may be a quantitative parameter for the division of tectonic units. The complex pattern of the earth’s surface is resulted from tectonic movement (endogenetic forces) and all kinds of complex hypergeneses (ex ogenic forces). The former controls the topographic inequality on larger scale a nd the latter shapes surface configuration on smaller scale. The fractal dimensi on values can indicate the maturity of the earth’s surface. During the earlier growth stage, the structural fractal dimension value on a larger scale is larger than the textural fractal dimension value on a smaller scale, and contrarily, d uring the later stage the textural fractal dimension value will be larger than t he structural fractal dimension value. At the same time, we can determine the sc ale of the tectonic movement in a district by its fractal scale of the earth’s surface, and what’s more, the scale can help us to study the structural geology and mineral exploration in this district.