Distribution of Heavy Minerals along the Beach from Mandapam to Kanyakumari, Tamil Nadu

Frequency distribution of heavy minerals along the southern Tamil Nadu coast from Mandapam to Kanyakumari shows selective deposition of heavies with respect to their densities. In Kanyakumari sector in the south, the heavies are concentrated in coarser sands, in the central Tuticorin sector in medium sands, and in the northern Mandapam sector in fine sands. Weight percentage distribution of heavies shows poor concentration at Mandapam that can be ascribed to strong progradational activity and wave-divergent conditions. A higher concentration of heavies in the ephemeral stream mouths in Tuticorin sector is due to the arcuate nature of the coastline, strong convergence of orthogonals and a basinal structure, all of which enable trapping of sediments carried by littoral currents. The poor concentration of heavies in Manappad sector, despite wave-convergent condition, is due to the straight alignment of the coastline without any arcuate bays. The enrichment of heavies in Kanyakumari sector is attributable to the arcuate coastiine and a downwarped basinal structure.