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Abstract
Sefidrud River Delta, which is the largest Iranian delta in the southern coast of Caspian Sea, was formed during the last two million years and has a complex evolutionary history. Its delta – making process is different form that of open seas because of being enclosed. Frequent movement change of its estuary has had an effective role in the evolutionary process of the delta, but the movement rate has gradually diminished. The role of West – East sea currents in sediment movement in Delta morphology has been neglected. The rise of Caspian sea level to a small rate by itself cannot prevent the delta expansion. The formation of sand spits, barrier islands and shoals play an important role in deltas evolutionary process. In this article, an attempt is made to investigate the evolutionary process of Semidried River Delta using historical resources, topographic maps, Arial photographs, Landsat images, and finally field studies.
Kay words : Sefidrud River Delta, Estuary, Geomorphological Evolution, Quarternery