Heavy mineral distribution and geochemical studies of coastal sediments between Besant Nagar and Marakkanam, Tamil Nadu, India

The main objectives of the present study are to understand the heavy mineral distribution, trace elemental distribution and to study the variation, if any, between the grain size and trace elemental distribution within the beach. Totally 20 stations have been collected and weight percentage of heavy minerals are identified. In the present study area most of the sands are fine and medium grained, indicates beach environment and most of the grains are positively skewed. The study area contained a high percentage of orthopyroxene (hypersthene) and garnet, rounded and broken zircons inferred to have been derived from charnockites and granulite gneiss of the study area. Overall from the geochemistry studies, it is observed that the Ni and Cr are more dominant and higher concentration in Panayar (station no. 2), Mahabalipuram (station no. 6), Kalpakkam (Station no. 7) and Perunthuravu (station no. 8). The present study has clearly indicated the multiple roles of tectonically controlled coastal blocks and their geomorphological influence in redistributing the sediments with favourable NE–SW configuration and wave energy conditions must have contributed to the formation of heavy minerals in a particular zone.