Survey of active tectonic: the influence of river morphotectonic in Aras Basin

The Aras Basin covered a wide area between Iran, Armenia, Azerbaijan, and Turkey countries. In this study, we focused on basins that are located in NW of Iran. Zagros folding belt, volcanic masses of Sabalan, and Ararat are the main structures. The present study aims to assess the analysis of basin morphotectonic indices. Using the digital elevation model under ArcGIS techniques, we created 44 sub-basins. Then, the six morphotectonic indices including hypsometric integral (Hi), drainage basin asymmetry (Af), drainage basin shape (Bs), mountain front sinuosity (Smf), stream-length gradient (SL) index, and transverse topography symmetry (T) were analyzed and showed as map. After normalizing the map units, to access the tectonic activity, the indices of related active tectonics (IAT) were calculated. To this purpose, result of the six indices was averaged and separated in 3 classes of tectonic activity from low, moderate, to high values. Based on the IAT map, most of the study area have moderate-to-low relative tectonic activity. The basins with numbers 10, 13, 17, 22, 27, 28, 34, 36, 37, and 40 showed the high tectonic activity and mostly correspond with the active structures in the basin including Hamzehloo, Mazan, Balaban, Arabshah, Mohammad Abad, Kafil, and Zarabad faults. Generally, the fault activity will disturb the order of the basin parameters such as shape, slope, and symmetry.