Geographical Research

Ground water flow and skin is the most important phenomenon in the process streams are involved not only in the face of the whole earth، but also of the life of man on Earth can. Degradation of coastal erosion، lateral stability and continuity in Iran and around the world each year destroys fertilized agricultural lands around the river، coastal installations، bridges، and is General houses. This causes erosion at the river Chrdavl Chenareh in the range studied. During the course of the river in order to 5/1 km was selected and harvested field operations. After the TIN created using HEC-Geo RAS amendment to link the HEC-RAS model and software ArcGIS 50 provides a cross-section of the model is introduced and values of the Manning coefficient model was introduced. With the introduction of the geometrical characteristics of the river flow characteristics and the Manning coefficient model، HEC-RAS، characteristics of flood flows for return periods of 5، 25، 50، 100 and 200 are set and used to determine and identify areas susceptible to erosion and sedimentation rates Minimum and maximum shear stress and velocity across the range for different flood return period was determined. Finally، the bank erosion. The minimum shear stress for different flood return period equal to N / m ^ 2 12/7، which occurred on the left coast، so Left Coast Range Chenareh most vulnerable place for the deposition. Field visits the accuracy of the calculations and the results of recent research shows.