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Revision: Geography (Contemporary India-II) >> Minerals and Energy Resources Social Science English Medium Class 10 CBSE

Definitions [2]

Definition: Minerals

Geologists define mineral as a “homogenous, naturally occurring substance with a definable internal structure.”

Definition: Alluvial Deposits / Placer Deposits

Certain minerals may occur as alluvial deposits in sands of valley floors and the base of hills. These deposits are called ‘placer deposits’ and generally contain minerals, which are not corroded by water.

Key Points

Key Points: Minerals

Rocks are made of minerals; some rocks, like limestone, have one mineral, but most contain many minerals in different proportions.
Though over 2000 minerals are identified, only a few are common and form most rocks.
The properties of minerals (colour, hardness, crystal form, lustre, density) depend on the physical and chemical conditions of their formation.
Geographers study minerals for their distribution and economic use, while geologists study their formation, age, and composition.
Minerals are classified as metallic and non-metallic; ores are minerals from which metals are extracted (e.g., bauxite → aluminium).

Key Points: Classification of Minerals

India has rich but unevenly distributed mineral resources.
Peninsular rocks contain most coal, metallic minerals, mica, and non-metallic minerals.
Petroleum is mainly found in the sedimentary rocks of Gujarat and Assam.
Rajasthan has many non-ferrous minerals, while the northern plains lack economic minerals.
A mineral deposit becomes a mine only when concentration, easy extraction, and market closeness make it viable.

Key Points: Metallic Minerals> Ferrous Minerals

Ferrous minerals make up about three-fourths of the value of metallic minerals and support metallurgical industries.
Iron ore is the backbone of industrial development; magnetite (up to 70% iron) is the best quality, while hematite (50–60%) is most widely used.
In 2018–19, about 97% of iron ore came from Odisha, Chhattisgarh, Karnataka, and Jharkhand.
Major iron ore belts include Odisha–Jharkhand, Durg–Bastar–Chandrapur, Ballari–Chitradurga, and Maharashtra–Goa.
Manganese is essential for steel making; about 10 kg of manganese is needed for 1 tonne of steel.

Key Points: Mode of Occurrence of Minerals

Minerals occur in ores, where extraction is economically possible.
In igneous and metamorphic rocks, minerals are found in veins and lodes (e.g., copper, zinc).
In sedimentary rocks, minerals occur in layers or beds (e.g., coal, iron ore, salt).
Bauxite is formed by the weathering of surface rocks.
Some minerals occur as placer deposits (gold) and in ocean waters (salt, manganese nodules).

Key Points: Non-Conventional Sources of Energy

Overuse of fossil fuels causes pollution, so renewable energy is needed.
Non-conventional sources include solar, wind, biogas, tidal, geothermal, and nuclear energy.
Nuclear energy uses uranium and thorium found in Jharkhand, Rajasthan, and Kerala.
Solar energy is widely used in rural areas using photovoltaic technology.
Wind energy is important in Tamil Nadu, Gujarat, and Rajasthan (Jaisalmer).
Biogas (Gobar gas) uses waste and gives energy and good manure.
Tidal and geothermal energy are found in the Gulf of Khambhat, the Sundarbans, Manikaran, and the Puga Valley.

Key Points: Conservation of Energy Resources

Energy is essential for all sectors, like agriculture, industry, transport, and households.
Since Independence, energy consumption has increased due to economic development.
There is an urgent need for sustainable energy development.
Energy conservation and renewable energy are key to sustainability.
We should save energy by using public transport, switching off unused electricity, and using power-saving devices — energy saved is energy produced.

Key Points: Conventional Sources of Energy

Coal is the most abundant fossil fuel in India and the main source of commercial energy; major coalfields are Jharia, Raniganj, and Bokaro.
Coal types include peat, lignite, bituminous, and anthracite; lignite is mainly found in Neyveli (Tamil Nadu).
Petroleum is an important energy source and raw material for industries; major oil fields are Mumbai High, Gujarat, and Assam.
Natural gas is used as fuel and industrial raw material; major reserves are in the Mumbai High, Krishna–Godavari basin, and the Cambay basin.
Electricity is generated as hydel power (renewable) and thermal power (coal, oil, gas); major projects include Bhakra Nangal and Damodar Valley.

Key Points: Energy Resources

Energy is essential for daily activities like cooking, lighting, transport, and industry.
Energy comes from fuel minerals such as coal, petroleum, natural gas, uranium, and electricity.
Energy resources are classified into conventional and non-conventional sources.
Conventional sources include firewood, dung cakes, coal, petroleum, natural gas, and hydel/thermal electricity.
In rural India, over 70% energy needs are met by firewood and dung cakes, but their use is declining due to deforestation and loss of manure.

Key Points: Conservation of Minerals

Mineral resources are essential for industry and agriculture, but form only about 1% of the Earth’s crust.
Minerals take millions of years to form and are finite and non-renewable.
Continuous mining increases costs as ores are extracted from greater depths with lower quality.
Minerals must be used in a planned and sustainable manner with better technology.
Recycling, use of scrap metals, and substitutes help conserve minerals for the future.

Key Points: Non-Metallic Minerals

Mica splits into thin sheets and is widely used in the electrical and electronic industries due to its insulating properties.
Major mica-producing areas are the Koderma–Gaya–Hazaribagh belt (Jharkhand), Ajmer (Rajasthan), and Nellore (Andhra Pradesh).
Limestone is a non-metallic mineral found in sedimentary rocks and is the basic raw material for cement and iron smelting.
Mining hazards include health problems from dust and fumes, and risks like roof collapse, flooding, and fires.
Mining causes land, water, and soil pollution, so strict safety and environmental laws are necessary.

Key Points: Role of Minerals in Human Life

Vehicles and machines are made from metals like iron and aluminium.
Metals are obtained from minerals found in the earth’s crust.
Minerals are essential for buildings, roads, and machinery.
Daily items like toothpaste contain minerals such as silica and fluorite.
Minerals form only 0.3% of our diet but help use the remaining 99.7% of food.

Key Points: Metallic Minerals> Non-Ferrous Minerals

Non-ferrous minerals like copper, bauxite, lead, zinc, and gold are important for metallurgical, electrical, and engineering industries.
India is deficient in copper; it is widely used in electrical cables, electronics, and the chemical industries.
Major copper-producing areas are Balaghat (Madhya Pradesh), Khetri (Rajasthan), and Singhbhum (Jharkhand).
Bauxite is the main ore of aluminium, which is light, strong, malleable, and a good conductor.
Major bauxite deposits are in the Amarkantak Plateau, Maikal Hills, and the Bilaspur–Katni region; Odisha was the largest producer in 2018–19.