Today India is self-reliant in many essential mineral commodities like iron, alumina, manganese, copper, lead, zinc, limestone, mica, coal etc. and at the same time imports many other strategic and high-grade minerals to cater to the need of various industries.
By G. Nagendran & A. Anil Kumar,
Geological survey of India (GSI) is the national agency in India engaged in exploration of minerals within the territory of India, including minerals underlying the ocean within the territorial waters and exclusive economic zones. Since initiation in the year 1851, GSI could cover approximately 3.2 million sq.km area of Indian land mass by systematic geological mapping. Today India is self-reliant in many essential mineral commodities like iron, alumina, manganese, copper, lead, zinc, limestone, mica, coal etc. and at the same time imports many other strategic and high-grade minerals to cater to the need of various industries. Around the world, many of the critical industrial minerals are fast depleting and countries in the world have imposed ban on exports of some of the industrial critical minerals like Rare Earth Elements (REE) that forms non-replaceable components in the modern technology-based industries. Towards India’s venture in every sphere of economic and industrial development, GSI has a major role to play in providing mineral raw materials for the agriculture and industrial sector. To accomplish the fast depleting and rarely occurring land based natural resources, GSI gave emphasis on offshore survey and exploration by systematic geological mapping of 2.159 million sq.km area of the Indian Exclusive Economic Zone (EEZ) including the 0.158 million sq.km of the Territorial Waters (TW) of India, for demarcation of offshore mineral potential areas, since 1985.
Through systematic surveys, GSI has been successful in identification of mineral potential zones within the Indian EEZ, some of which could be converted into potential offshore resource through systematic exploration. The offshore resource potentials of heavy mineral (HM) placers (including Ilmenite, Monazite, Zircon, Rutile, Sillimanite and Garnet) within the TW can be converted to offshore reserves, subject to compliances of several other factors like feasibility studies, studies on mineral economics and environmental impact analysis, either through outsourcing or collaboration, whichever is feasible. Potential heavy mineral zones have already been demarcated from the TW off Odisha, Andhra Pradesh, Tamil Nadu, Kerala, Maharashtra for future thrust areas for detailed explorations leading to exploitation. GSI has developed future strategies for investigation of vanadium, thorium and rare earth elements by systematic exploration, with the inputs from different Nation and International agencies/ institutes, wherever required, for further developments. Offshore resource of high-grade lime mud of more than 100 billion tonnes, within the Indian EEZ off Gujarat, Maharashtra and Andhra Pradesh, has been established for the future exploration and further exploitation subject to compliances of other related issues, presently not under the purview of GSI.
Potential zones of construction sand, occurrences of phosphate rich sediments, poly-metallic crusts and nodules and rare sulphide minerals have been reported from the TW off Kerala, Tamil Nadu coasts and within the Andaman Sea and Lakshadweep Sea. Though India at present is Atma Nirbhar in limestone resources required for the cement and manufacturing industries, the future requirement of high-grade limestone for the steel and chemical industries, may be accomplished through offshore lime mud resources. Fertilizer minerals like rock phosphate and potash plays a vital role in the economic development of an agriculture-based economy like India. Today, the Indian fertilizer industries largely depends on imports of raw material to bridge the demand-supply gap. GSI in the recent years have reported occurrence of phosphate bearing minerals from the continental shelf and seamounts off Gujarat, Maharashtra, Karnataka, Kerala and Tamil Nadu and potash rich glauconitic sand from the Tamil Nadu offshore. Further explorations are progressing to understand their economic potential and mining feasibility. Construction sand, the minor mineral commodity is in high demand in the Southern States of India, especially in Kerala. To address the issue of construction sand scarcity in the state of Kerala, GSI has identified offshore resources of construction sand from the TW and contiguous zone off Kerala.
Ferromanganese crust and nodules from the ocean floor are well known for their rich metal content of cobalt, nickel, copper, zinc, gold, platinum, REE and many other strategic metals. While many countries in the world including India had been searching desperately in the deep ocean floor for such metalliferous deposits, for claiming mining rights from the International Seabed Authority, through systematic surveys, GSI could bring out widespread occurrence of such metalliferous crust and nodules from the Indian EEZ region surrounding the Andaman & Nicobar Islands. These nodules and crusts have manganese (7% to 18%), cobalt (650 ppm to 2095 ppm), zinc (422 ppm to 771 ppm), nickel (497 ppm to 7760 ppm), platinum (522 ppb to 1223 ppb) and REE (635 ppm to 1908 ppm). Sporadic occurrence of such nodules and crusts were also unearthed from the vicinity of Lakshadweep Islands.
Mining of these minerals after detailed exploration and studies on economic feasibility would be a big leap towards making India Atma Nirbhar in raw materials for electronics, ceramics, glass, rubber, refractories, cement, fertilizer, iron and steel and chemical industries.
Taking lead from the baseline as well as exploration data generated so far, GSI in the coming years plans to carry out survey for further systematic high resolution base line data generation within the EEZ and beyond, followed by selective explorations, either by outsourcing [with National Mineral Exploration Trust (NMET) fund] or in-house capability. The identified offshore resource potential areas for HM Placers, Lime mud and Construction sand are 900 sq. km, 250 sq. km and 100 sq. km respectively. For the in-house capacity building, process of acquisition of research vessels with advanced high-end equipment as replacement for existing more than three and half decades old coastal research vessels is in pipeline. Further GSI plans to extend its contribution towards societal issues and public good geosciences pertaining to offshore sectors along with exploitation of nearshore proved resources. GSI is also planning to venture in the deep ocean, in the International Waters towards systematic baseline data generation and searching of strategic and critical minerals by its own expertise, experiences and available in-house capabilities.
(The authors are Director, M&CSD at Geological Survey of India, Mangalore. Views expressed are personal and do not reflect the official position or policy of the Financial Express Online.)