Geologists strike huge mineral deposits in Indian seas

Scientists from the Geological Survey of India (GSI) are reported to have discovered the presence of millions of tonnes of precious metals and minerals deep under the waters that surround peninsular India, say reports.

During deep sea explorations, researchers are reported to have stuck upon huge amounts of lime mud, phosphate-rich and calcareous sediments, hydrocarbons, metalliferous deposits and micronodules that they see as a clear indication that deeper and more extensive exploration could lead to larger finds.

The huge presence of marine resources was first identified off Mangaluru, Chennai, Mannar Basin, Andaman and Nicobar Islands and around Lakshadweep in early 2014.

High-resolution seabed morphological data obtained from exploration of 181,025 square kilometres of seabed by the GSI has helped establish the occurrence of more than 10,000 million tonnes of lime mud within the Exclusive Economic Zone of India.

Explorations have also helped confirm the presence of phosphate sediment off Karwar, Mangaluru and Chennai coasts, gas hydrate in the channel-levee system of Mannar Basin off the Tamil Nadu coast, cobalt-bearing ferro-manganese crust from the Andaman Sea and micro-manganese nodules around Lakshadweep Sea, according to reports.

The 'High Resolution Seabed Mapping and Natural Resource Evaluations' were carried out using three state-of-the-art research vessels - Samudra Ratnakar, Samudra Kaustabh and Samudra Saudikama. "The main objectives were to identify potential zones of favourable mineralisation and evaluate marine mineral resources," said Ashish Nath, superintendent geologist at GSI.

Seabeds containing large quantities of metals and minerals have emerged the next frontier for mineral exploration as land-based deposits of similar composition have almost exhausted.

According to the International Seabed Authority (ISA), marine nodules (lumps of minerals), which take millions of years to form, are found everywhere around the oceans and seas. However, deposits with economic potential are mainly found in three areas - north central Pacific Ocean, the centre of the northern Indian Ocean, and the south-east Pacific.

Nodules contain 28 per cent metal, mainly manganese (26 per cent), iron (6 per cent ), silicon (5 per cent), and aluminum (3 per cent). But also, in lesser quantities, other valuable materials, such as nickel (1.4 per cent), copper (1.3 per cent), cobalt (0.25 per cent) and rare-earth minerals (REMs).

While oil was the big commodity found offshore for many years, diamond giant De Beers has found some of its most valuable gems on the Atlantic Ocean seabed off the coast of Namibia.

They are literally vacuuming them off the ocean floor. The world's biggest diamond producer has spent $157 million on a state-of-the-art exploration vessel that will scour 6,000 square kilometers (2,300 square miles) of ocean floor for gems, an area about 65 per cent bigger than Long Island. The Anglo American Plc unit mines in the area in a 50-50 joint venture with the Namibian government.

With the gradual depletion of land-based mineral deposits, the mines of the future will be located at the bottom of the ocean.