Morphology and Sediments of the Cox's Bazar Coastal Plain, South-East Bangladesh

Abstract

The paper highlights the broad hydrogeomorphological characteristics of the Cox's Bazar coast of Bangladesh. High resolution air photographs of 1:20000 were interpreted for delineating the geomorphological boundaries of the coastal plain. Sediment samples collected from the each geomorphic units were analysed to understand the sedimentary environments. Based on the location and characteristics of the geomorphic units and types and spatial distribution of sediments, evolutionary history of the coast was developed. Finally, a weighted matrix was prepared for assessing the exposure of the geomorphic units to geohazards e.g., storm surges, flash flood. The study reveals that the coast of Cox's Bazar has landforms of two distinct origin: fluvial and marine. Beach and dunes are the two most prominent features of the coast. The sedimentation and its evolutionary sequence of the coastal plain indicates an infiling of a sheltered basin within a relatively high wave and micro- to meso tidal conditions. Cyclonic storms/storm surges appears to be the most common geohazard for most of the landform types of the area. Floodplain with most of the infrastructural investments would need protection from storm surge and flash flood.