ESTIMATION OF FRACTAL DIMENSION OF GLOBAL RELIEF

Since B. Mandelbrot put forward the concept of fractality of the Earth 's surface relief more regional evidence have been adduced in its supp ort. An attempt is made tc subject this concept to a global test. On t he base of a one-degree grid elevation values lengths of different top ografic isolines were computed for seven grades of averaging. It was a scertained that elevation contours are really fractal lines with fract al dimension significantly greater than unity (1.30 and more) at the s cales from 100 to 2 000 km. Some additional considerations allow to ex tend these limits to 5 km and 20000 km respectively. Dependence of dim ension value on contour elevation is estimated. A simple model is sugg ested imitating self-similarity of relief contours at different scales .