Morphological Uniqueness of Beach Sindhudurg District, Maharashtra, India

This chapter represents the beach morphology in a section of the coast of Maharashtra. The coastline of Maharashtra extends over a length of 720 kms. From Dahanu in the north to Redi in the south along the Goa border. The present study confines attention to the extreme southern section of this coast. The selected area for this study was district of Sindhudurg which extends between 15°45’ N latitude and 16°30’ N latitude It has a general orientation north-northwest to south- southeast. The coastline has a total length approximating to about 100 kms. The study area forms the talukas of Devgad, Malvan and Vengurla of the Sindhudurg district.

To study the variations in beach morphology, a field work was carried out in October-November 1989 after the end of the monsoon season to collect sand samples for textural analysis and chemical analysis. The pH values of the beach sand samples were also determined in the laboratory. A study was also carried out to find out if there was any relationship between texture and angle of the beach. Fourteen samples taken from different locations spread all over the shores of the study area. Beaches are composed of sediments derived from the disintegration of the land – sand and gravel eroded from terrestrial rocks. The composition of beach sediments reflects the nature of the source rocks and often can be used to assess relative contributions and transport paths from the sources to the beaches. Waves and nearshore currents continuously rework the accumulated beach sediment, rounding the particles and sorting them by size, shape and density. The beach takes on a form that reflects the totality of water and sediment movements. Most of the beaches reveal a fine sand proportion of a preponderant percentage ranging between 55% and 90%. Trap country beaches are associated with acidic reaction, while quartzites have comparatively higher pH value ranging between 6 7 and 8. From the scattergram and trend of the regression line it is noted that there is a direct and positive relationship between the percentage of sand and the gradient angle of the beach.

The overall morphology of the beach reflects the composition of its sediments and the physical processes of waves, currents and sediment transport.