Interaction between sediment transport rate and tectonic activity: the case of Kizilirmak Basin on the tectonically active NAFZ, Turkey

The degree of interaction between sediment transport rate and tectonic activity is a major issue that draws the attention of researchers. Because of the complexity in the modeling process of uplift and subsidence rate, it is quite difficult to determine the rate of interaction between erosion and tectonic activity. In this study, the sediment transport rate of Kizilirmak Basin, which is located on the tectonically active North Anatolian Fault Zone (NAFZ), was investigated to determine the effect of tectonic activity on sediment transport rate. The sediment transport rate of the basin was evaluated by using the drainage channel width, the topographic wetness index (TWI), and the revised universal soil equation (RUSLE) model. The Aster Global Digital Elevation Model (GDEM), Landsat 8 Operational Land Imager (OLI) scenes, a 1:800,000 scale soil map, and 30 years of rainfall records at 41 stations were used for the analysis. The drainage channel width, the TWI, and derivation and grid-based integration of the RUSLE parameters were performed by using GIS (terrain analysis, spatial data analysis) and remote sensing image processing techniques. The relationship among the derived parameters and tectonic activity was evaluated by Getis-Ord Gi*statistics. The results show that at the 99 and 95% confidence intervals, statistically significant cold spot values of the channel widths, hot spot values of the mean annual soil loss values, and cold spots of the TWI values are more intensely clustered around fault lines. These clustering areas not only indicate the areas where the rate of sediment transport is high, but also the areas where the tectonic activity of the NAFZ is more vigorous.