Morphodynamic classification of beaches has achieved widespread acceptance in both geological and geomorphological literature. Geomorphologic characters of the beaches are shaped by wave’s actions directly or indirectly and ultimately induce the sediment transport and the morphological features are curved in relation to beach profiles. Beach morphodynamics is the reaction and interaction of wave height, wave period, tidal range, dune height etc. The aim of the study is to determine the morphodynamic changes based on beach profile, swell characters and granulometric study along the coastal areas of Mandapam to Vallinokkam of Ramanathapuram district located in eastern part of southern Tamilnadu. Morphodynamic condition and changes along the coastal length of 50km are recorded. The distribution of grain size parameters along coastal stretch reveals that the mean grain size of sediments in dune, berm, slope and water level are mainly of medium, fine to coarse grain, moderately sorted, very fine skewed and very leptokurtic to mesokurtic in nature. The Inter-relationship of various parameters shows the natures of sediments in slope, berm and dune having dominance of fine grain to coarse sand distribution. The significance emphasises that the modern sediments in the study area are deposited based on rolling and suspension in field and by mixing of different sizes and class of sediments by wave action. Morphodynamic condition along the study area is characterized as high energy gradient, convex profiles and reflective beaches.
