Delineation of high water line and seasonal beach profiling at Kalbadevi Bay, Maharashtra, central west coast of India

Abstract

Seasonal morphological variations and effect of oceanographic processes such as erosion or accretion along beaches are important to understand the nature of the beach and the cyclic changes occurring during different seasons. These studies are more significant in the areas where rich beach placer deposits are occurring. This will help in understanding replenishment of these heavy minerals in the areas of interest. This report describes results of similar studies (seasonal variations of high water line and beach profiling) carried out at Kalbadevi Bay, which is in Maharashtra along central west coast of India. Kalbadevi Bay is one of the most important prospective area for heavy mineral placers rich in Ilmenite and Magnetite. The required data were collected by using highly sophisticated instruments like Laser Trak, DGPS (Differential Global Positioning System) and Automatic level (Carl Zeiss Make) following the standard survey techniques. Beach profiles at three sites in Kalbadevi bay has clearly shown the specific zones of sand erosion and sand accumulation at various periods. Natural morphological beach features such as the erosional scarp, monsoonal berms and permanent vegetation line, reflect the positions of maximum high water levels and the berm crust reflects the positions of frequent ordinary high water levels. This report analyses the field data collected at different seasons at Kalbadevi Bay and presents the results of the field observations with final processed high water line maps and beach profiles. The report also highlights the methods involved and the instruments used in collection of the field data.