The effect of morphotectonic factors on erosion and change of longitudinal profile of river using the mathematical functions (Case Study: Alvand River in the West Kermanshah Province)

The river’s Geomorphology and its evaluation explore explanation of erosion, the longitudinal profile of the river bed and different forms of the rivers. Alvand River as the main river of the Alvand basin is located in Kermanshah Province W, Iran. The aim of this study is to investigate changes in longitudinal and longitudinal profiles of the river bed using mathematical functions and their relationship with the land and its base. Using the Applied-Developed research method, analytical-statistical and field study method is used in this paper.The results show that, the evaluation of longitudinal profiles and morphological forms of the river bed is in relation with various factors such as erosion, tectonics, lithology and geomorphological elements such faults. The rivers located in the upper part, are fitted with a linear function due to this part of the basin is affected by activities tectonic. The middle and low parts except Alvand 2 which are affected by tectonic activities, other parts due to tectonic activity on weak lithologycal structure, have been fitted with an exponential function and contains bed and bank erosions.