A PRELIMINARY FRACTAL ANALYSIS OF FAULTING IN THE ZAGROS THRUST BELT

Recently, the concept of fractal geometry is used widely to describe various aspects of complex systems. The structure and the seismicty of fault systems can also be well described in terms of fractals. The fractal dimension is a measure of the degree of both heterogeneity and the irregularity of a fault system. The Zagros Thrust Belt is a part of the continental collision zone between the Arabian and the Persian plates showing a high degree of seismic activity associated with complex faulting composed of generally low angle reverse and rarely vertical. In this study the structure of faulting in the Zagros Thrust Belt is investigated by fractal analysis using a ۱:۲,۵۰۰,۰۰۰ scaled seismotectonic map of Iran. The most spectacular part of the thrust belt between ۴۴۹,۰۰' E and ۵۶°,۰۰' E longitudes is divided into nine equal segments and the fracial dimension D is computed for each segment by using the box counting algorithm. Our results show that the fractal dimension D in the Zagros thrust belt ranges between ۱.۱ and ۱.۶. The fractal dimension of individual segments tend to increase with increased thrusting. This may be encouraging that the fractal analysis can be used to identify structural variations in a seismotectonically complex area.