India is expected to take up at least three investigations for Fe-Mn (ferro manganese) crusts/nodules — one each in the Andaman Sea, Indian Ocean, and Arabian Sea; while one high-resolution seabed mapping programme will be mounted over the Lakshadweep Sea in search of polymetallic crusts and nodules.

Polymetallic nodules generally contain nickel, cobalt, manganese ore and copper, among others, which are used for the production of batteries for electric vehicles.

According to officials from the Ministry of Mines, the Geological Survey of India (GSI) has been exploring India’s Exclusive Economic Zone (EEZ) in Andaman and Arabian sea and has observed occurrences of ferro manganese crusts. Surveys are on to find more such nodules.

The marine surveys are done by the Marine and Coastal Survey Division (MCSD) of the GSI, the Minister, Prahlad Joshi had recently said in a written response to the Parliament while pointing out that the Centre has not given licence to domestic or global players for this.

At present no mining activity for poly-metallic nodules are going on within the exclusive economic zone.

Nickel enrichment

In the Andaman Sea, occurrences of hydro-genetic or dia-genetic polymetallic Fe-Mn crust and nodules are found in seamounts like West Sewell Ridge (WSR), located to east of Nicobar Island and Sewell Rise (SR), located close to the Andaman Back Arc Spreading Centre (ABSC). Crusts and nodules in Andaman Sea shows average nickel enrichment of 0.25 per cent.

A recent survey around Cherbaniani, Byramgore, Perumul Par and Bitra Par Reefs, Lakshadweep Trough in the Arabian Sea brought out the occurrences of seamount associated crusts and nodules between 1,200 metres and 1,500 metres water depth along the flanks of reefs and small seamounts in the northern part of Laccadive Ridge system.

The polymetallic crusts and nodules in Lakshadweep Sea show nickel enrichment varies from approximately 0.1 to 0.54 per cent.

“In the current field season, 2022-23, two programs are assigned to take up polymetallic Fe-Mn nodules/crust investigation within the EEZ of India,” he had said.