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چکیده
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Rivers, as force vectors, play an important role in landform changes and have a significant impact on the human exploitation of their surroundings. Investigation on the characteristics and evolution of rivers is one of the topics of river geomorphology. On the other hand, determining the fractal dimension is very important in understanding the behavior and predicting changes in river evolutioncourse. This study was conducted to analyze the relationship between geomorphological characteristics and fractal dimension of the Dinvar river basin. To achieve the above goal, the required data were extracted from topographic maps 1: 50000, geology 1: 1000000, digital elevation model (DEM) with a pixel size of 30 × 30 meters and also Google Earth software. In order to conduct this research, we first prepared the streams map and the boundaries of the Dinvar basin in the Google Earth software environment. Then the stream ordering was done using strahler method and the boundaries of the basins were drawn at the end of the stream with a rank of six and the Dinvar basin was divided into two basins, north and south. Fractal dimensions of rivers and faults were calculated by fractal tree, Turcotte and capacity dimension methods. Morphometric indices include basin asymmetry, shape factor, compactness coefficient, river frequency, texture ratio, elongation ratio, basin relief, basin slope, ruggedness number, drainage density, relief ratio, bifurcation ratio, length to width ratio, rank to length ratio of streams were calculated. In the present study, the fractal dimensions of the streams in the northern and southern basins were based on box counting and Turcotte , fractal tree were 1.56-1.59, 1.26-1.25 and 1.79-1.95, respectively. The fractal dimensions of the faults for the northern and southern basins were in the ranges of 1-1.12 and 1.02-1.14, respectively. Shapiro-Wilk test was used to evaluate the normality of the data. After the calculations related to normalization, the means were compared between the two groups of northern and southern tectonics. The results showed that the morphometric indices on the small and large scales are influenced by lithology and tectonics, respectively
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