Remote Sensing revealed a morphotectonical view point on the deviation of Hirmand (Helmand) river courses  Reza Derakhshani Ph.D. student in Tectonics, Department of Earth Sciences, P.O. Box. 1673-71454, College of Sciences, Shiraz University, Shiraz, Iran. rezaderakhshani@yahoo.com  Godratollah Farhoudi Professor, Department of Earth Sciences, P.O. Box. 3000-71454, College of Sciences, Shiraz University, Shiraz, Iran. gfarhoudi@yahoo.com  Azizollah Vahed Water Authority of Sistan and Balouchestan, Zahedan, Iran. reza_1217@yahoo.com Abstract The Satellite captured remotely sensed images, provide unique and advanced possibilities in understanding the various morphotectonic features. This has possible because of the synoptivity, multispectral photocapacity and the repetitivity of the orbital satellites. Taking advantage of this technology, the raw and digitally processed IRS 1D satellite data and Landsat 7 ETM satellite data were interpreted for parts of Hirmand river trend, East of Iran and Southwest of Afghanistan. Combining landsat data processing, geological investigations, geomorphological evidence, and field observations with archeological information and historical documents, it is concluded that tectonic uplift of southern part or subsidence of northern parts of the study area plays the main role in deviation of Hirmand river trend. It should be noted that, high rate of sedimentation of river can causes, locally, some instabilities and deviations in Hirmand river trend. These investigations recognize seven different deltas in the study area (which are separable based on their relative ages) by revealing the deviations of Hirmand river trend in past time. |