Study of Sedimentology, Morphoscopy and Heavy Mineral Deposits in Jajrud River

  In this research we aimed to study the sedimentology of Jajrud River, upstream from Latian Dam. Initially, a field review was conducted to ascertain complete familiarity with the geographical and geological conditions of the proposed region. After determining the sampling location, the acquired samples were taken to the laboratory. From morphoscopic studies of the sediments, we have determined that particles often undergo changes during the river course. Hence these changes do not adhere to a particular process. Since Jajrud sediments enjoy diverse lithology with plenty of channels and waterways included, therefore it is natural that particle changes do not have a particular process. This is also due to the fact that particles with chemical composition and diverse mineralogy possess different resistances, sizes and primary shapes. The distance that particles cover are diverse, hence they would not remain the same due to the effects of erosion and corrosion. Jajrud River in the proposed study limit, has a 10.1 torsion coefficient, an average incline of 4%, the presence of abundant dams in its own bed (dam parameters more than 1), an average annual discharge (119.7 cu.m/sec during September and a maximum 6.208 cu.m/sec during April) the type of sedimentation (lack of suspension), and a mutilated river with a gravel-sand bed. Congruent quantity of heavy minerals is decreased in the final stage compared to the initial stages. It seems that heavy minerals, due to their particular high weight, are sedimented more in the initial stage and their quantity is decreased in the final course. Additionally, the quantity of magnetic heavy minerals (iron oxides) are decreased towards the utmost end, most likely due to the particular rust above them as well as increased sedimentation at the initial stage.