Geologists of Geographical Survey of India and National Institute of Oceanography are carrying out their research on the bottom of the various seas. It has been done in the Bay of Bengal, Arabian Sea, and the Indian Ocean for many years. They are making use of small mechanized boats.
These studies have shown quite encouraging results. The sea is blessed with various kinds of mineral deposits which are needed to be explored. Geologists have found around 288 million tonnes of calcareous sand up to the depth of one meter below the lagoon floors of Lakshadweep islands. This high-grade calcareous sand can form the excellent source for the formation of high-grade cement. The continental shelf covers an area of around one million square kilometers. It is approx one-third of the total land area of India.
Types of Minerals Found in Continental Shelf
Continental shelf contains basically three types of minerals-
- Terrigenous Minerals
- Biogenous Deposits
- Chemogenous Deposits
- Terrigenous Minerals- Recent studies of GSI and NIO have found huge mineral deposits of ilmenite, monazite and calcareous sands under the sea. The coast of Maharashtra, Kerala, Tamil Nadu, Andhra Pradesh and Orissa contains these mineral deposits. Ilmenite produces Titanium. Titanium is an important metal for manufacturing supersonic aircraft and paints. Monazite sands produce radioactive metal thorium.
- Biogenous Deposits- Studies shows that biogenous deposit contains shell pieces and skeletal debris of marine organism at the ocean floor. Currently, India mines Kerala’s Vembanad Lake and the Gulf of Kutch.Studies have shown similar deposits in the Gulf of Mannar, the Palk Straits and at the sides of coasts of few Andaman and Nicobar islands. Lagoons of the Lakshadweep islands contains a reserve of around 1,400 million tonnes of coral sand. These deposits contain pure calcium carbonate for various uses in industries.
- Chemogenous Deposits- Chemogenous deposits are manganese nodules. These are in shape of potatoes and contain manganese (19%) and iron (12%). These deposits also consist of a small recoverable amount of nickel, cobalt, and copper. The estimated reserve of manganese ore on the land is around 68 million tonne. Out of which, India is mining around two million tonnes.