Geomorphology of the Iranian coast of the Caspian Sea

Abstract

Geomorphic features of the Iranian coast of the Caspian Sea closely resemble those of the western coast within the USSR borders. Three geomorphic zones are distincly distinguished. 1) Present-day beach and New Caspian built-up terrace with superimposed sand dunes near its axial part, morphologically it is barrier beach built of sand and gravel which detaches from the sea relict of ancient lagoons and two large recent ones, i. e. Mordob and Gorgan lagoons. 2) Zone of alluvial terraced plain built mostly of products of intense erosion of Bogrovdag and Elburz Mts slopes and foothills; it includes three Late Khvalynian terraces, their absolute heights are - 17-12 and 0 meters, 3) Zone of terraced foothills, including mostly erosional Early Khvalynian terraces. The terraces heights are similar to those at the western coast which strongly indicates the Khvalynian transgressions were of mostly hydrocratic origin. Characteristic feature of the coast formation is abundant supply of the coastal zone with terrigenous material due to abundant precipitations and active erosion at the Elburz Mts slopes.