تعيين مراحل تحول ژيومورفولوژيكي دره هاي نواحي كوهستاني با روش هاي كلاسيك و رياضي

The Determining of Geomorphological Evolution Stages of Valleys, in Mountain Regions with Using of Classical and Mathematical Methods Case study :11 Main Valleys and Basins of the Sahand Mt

The curve of longitudinal valleys profile, which reflects, geomorphological characteristics of the basins ,tectonical and climatical events, is very different.With results of these analyses, study of the aggradation and degradation processes is possible. n this article,with using of classical and mathematical methods ,is surveyed all basins and main valleys. The main rivers of the Sahand Mt which drain water into two large basins, flowing in deep valleys.Those valleys have analyzed regarding to the change of riverbeds and the type of channel profile with attention to focuse on the concavity of the valley profile on this basin, we tried to determine the evolution of the Sahand,s valleys thus estimate their long-term evolutionary tendencies.Regression analysis between relative distance and altitude was performed for the longitudinal profiles of 11 valleys in the Sahand mountain. Each profile can be expressed by one of exponential, power, logarithmic and linear functions.Most valley show a good fit to power functions. Different function types show different curvature of the profiles.Valley fitted with exponentions have their profile is larger than their curvature, those fitted with power functions have small curvature and those fitted with linear functions show almost straight lines.The valleys have grouped according to the mathematical models or function which fit the best: the exponential, power, logarithmic and linear functions.Finlly we tried to conclusion with traces in field.