Sedimentological and Geomorphological Classification of Chabahar Coastal Area (Chabahar-Gawater)

In the present paper various transects perpendicular to Iranian Makran coasts (Chabahar-Gawater) were studied using satellite image processing, field observations, sandy shore profiling and grain size analysis to evaluate sedimentology and geomorphology of the area. Data revealed that the study area includes exposed rocky shores (52%), sandy shores (40%), and mud flats (8%) sheltered in estuaries. Forming spectacular landforms, coastal cliffs are the most frequent features in the area and have evolved by action of both coastal Makran uplift (1-6 mm.yr-1) and wave induced erosion. Due to high tectonic activity and severe longshore drifting, sandy shores are narrow and less developed. The location and direction of backshore sand dunes observed by satellite images suggests that they are developed on top of cliffs and along paleoshorelines as a result of strong southwest monsoon winds. Estuaries formed by sedimentation of seasonal creeks are mostly sheltered by longshore associated sand barriers and spits. In some of estuaries, such as Bahukalat and Tiss, salt marshes are observed in mangrove forests. In general, the overall shape of Makran coastlines is governed by structural pattern of coasts. Other processes shaping coastal features include wind action, water runoff and weathering by physical, chemical or biological agents. Wave action, especially during summer monsoon has a fundamental role in coastal change.