Oceans: Geochemistry and mineral resources

Abstract

With increased exploitation of the onshore mineral resources, oceans that cover almost 71% of earth's surface and known as storehouse of minerals, provide a suitable alternative. Amongst the various underwater mineral resources, placer deposits, phosphorites, manganese nodules and encrustations, metalliferous sediments and hydrothermal sulphides are well studied. A variety of mineral deposits are known to occur within the EEZ of India. These include placer deposits along the east and west coast of India, phosphorite deposits off Goa and off Chennai, hydrothermal sulphides in the Andaman Basin. The polymetallic nodules from the Central Indian Basin have been studied in detail and as a result India was recognized as a pioneer investor. Further, Indian became the first country to have been allocated exclusive rights of exploration in the pioneer area in the Central Indian Ocean Basin. Presently world wide some of the near-shore deposits are being exploited. However, the mining for other mineral resources on the continental margins as in deep sea is currently uneconomical. With further depletion of onshore resources and advancement in technology, the mining of these resources may also become a reality in the near future.