Chapter 16: Minerals and Power Resources
Strike a match to a lump of coal, and you are burning sunlight that fell on the Earth about 250 million years ago.
At that time there was no India. The land that would become the peninsula lay far to the south, locked into a single vast supercontinent called Gondwana, joined to what are now Antarctica, Australia, Africa and South America. Across this crowded landmass grew dense, swampy forests. As the plants died, they sank into waterlogged basins where there was too little oxygen for them to rot away.
Layer after layer piled up. Rivers buried them under sand and mud, and the weight of the sediment, working with the Earth’s inner heat, slowly squeezed the water and gases out of the dead vegetation and packed the remaining carbon tighter and tighter. Over millions of years, wood became peat, peat became lignite, and lignite became coal.
Then Gondwana broke apart. India drifted north for tens of millions of years and collided with Asia. But the coal stayed put, sealed in the old river valleys — and the very same coal seams still turn up in Antarctica and Australia, silent evidence that these lands were once one.
Today, that buried forest lights our homes, smelts our iron and drives our trains. Almost everything modern India runs on was locked in the ground long before there was a country to dig it up.
Diagram
Fig. 16.0-1 Caption: Buried forests turn to coal as heat and pressure drive off water and gas and leave the carbon behind. Brief: A left-to-right cross-section in five stages — a living swamp forest, then the same forest buried under layers of river sediment, then peat, then lignite, then bituminous coal, ending in anthracite. Below the sequence run three arrows all pointing left-to-right, labelled increasing depth, increasing heat and pressure, and rising carbon content (roughly 50-60% in peat to over 80% in anthracite). Emphasise that depth and time increase together with carbon.
16.1 Minerals And Their Classification
Almost everything we manufacture — a steel rail, a copper wire, a cement wall, the chip inside a phone — begins as a mineral pulled out of the ground. Geography asks where these minerals lie, why they lie there, and what it costs to bring them up. Before any of that, we need to know what a mineral actually is, and how the many kinds are sorted.
16.1.1 What Is A Mineral
A mineral is a naturally occurring substance, of organic or inorganic origin, with a definite chemical composition and definite physical properties such as colour, hardness and lustre. Because its make-up is fixed, the same mineral behaves the same way wherever it is found.
Minerals occur inside rocks, which are themselves mixtures of one or more minerals. Not every deposit is worth mining, though. When a mineral, or the rock holding it, contains enough of a useful metal to be extracted at a profit, it is called an ore. Iron ore is rock rich enough in iron to be worth smelting; poorer rock carrying only a trace of iron is not an ore at all.
16.1.2 Metallic And Non-Metallic Minerals
Minerals are sorted first by whether they yield metal. Metallic minerals are those that give up a metal when smelted — iron ore, copper, bauxite, manganese. They are usually hard, carry a shine of their own, are often found in igneous and metamorphic rocks, and can be hammered into sheets or drawn into wire without shattering. Non-metallic minerals hold no metal to extract — mica, limestone, gypsum, coal. They usually lack that metallic shine, occur more often in sedimentary rocks, and tend to break into pieces when struck rather than bend.
Metallic minerals split again by their iron content. Ferrous minerals contain iron and form the raw material of the iron and steel industry — iron ore itself, and also manganese, chromite, nickel and cobalt, which are added to make different steels. Non-ferrous minerals carry no iron: gold, silver, copper, lead, tin, and bauxite, which is the ore of aluminium. Ferrous minerals tend to be greyish and go into heavy machinery, while non-ferrous minerals come in many colours and serve a wide spread of industries.
Non-metallic minerals divide by their origin. The organic ones formed from once-living matter — these are the fossil fuels (also called mineral fuels): coal, petroleum and natural gas, made from the buried remains of plants and animals. The inorganic ones, such as mica, limestone, graphite and gypsum, never lived; they are purely mineral in origin.
The whole scheme sits neatly in one branching diagram.
Flowchart
Fig. 16.1-1 Caption: How minerals are classified, from the broad split into metallic and non-metallic down to worked examples. Nodes: Minerals → splits into Metallic minerals and Non-metallic minerals; Metallic minerals → yields iron? yes → Ferrous minerals (iron ore, manganese, chromite, nickel); no → Non-ferrous minerals (gold, silver, copper, bauxite, lead, tin); Non-metallic minerals → formed from once-living matter? yes → Organic / fossil fuels (coal, petroleum, natural gas); no → Inorganic minerals (mica, limestone, gypsum, graphite)
16.1.3 The Character Of Mineral Wealth
Whatever their type, minerals share three features that shape how a country uses them.
First, they are spread very unevenly across the Earth. Geological accident decides which region gets which mineral, and no country holds all of them. India is rich in iron ore but short of copper — and the reason lies in the rocks, as the next section explains.
Second, quality and quantity tend to run in opposite directions. High-grade ore, rich in the wanted metal, is usually scarce, while low-grade ore, carrying more waste rock, is far more plentiful. The best deposits, being both rare and easiest to work, are mined first — so over time a country is left with poorer ore that costs more to extract.
Third, minerals are exhaustible resources: once burnt or smelted, they are gone. They took millions of years of geological time to form and cannot be remade to order when we need them. For this reason mining is sometimes called a ‘robber industry’ — it takes a crop that will never grow back. Minerals must therefore be used carefully and not wasted, a theme the chapter returns to at its close.
16.2 Where India’s Minerals Lie
Minerals are not scattered at random. They gather where the right rocks are, and the right rocks are found only in certain parts of the country. That is why a map of India’s mines looks so lopsided — crowded in the south and east, almost empty in the north.
16.2.1 The Geological Control On Distribution
Every mineral forms within a particular kind of rock, laid down at a particular time in the Earth’s history. So to find a mineral, geologists first look for the rock system that carries it. The distribution of minerals is really a map of India’s rocks.
India’s oldest rocks are the hard crystalline rocks — igneous and metamorphic rocks made of interlocking crystals, formed over 2,000 million years ago. These make up the peninsular plateau, and they hold most of India’s metallic wealth. Iron ore and manganese occur in the ancient Dharwar rocks; copper, lead and zinc in the Aravalli rocks of the north-west; limestone, dolomite and gypsum in the younger Cuddapah and Vindhyan rock systems.
Two younger sources matter for energy. Coal lies in the Gondwana rock system, laid down in old river basins roughly 250 million years ago. Petroleum occurs in the still younger Tertiary rocks, along the margins of the plains and out under the sea.
The northern plains tell the opposite story. Here rivers have spread a blanket of alluvium — fine sand, silt and clay — hundreds of metres thick, sealing the mineral-bearing bedrock far below. The Himalayas do hold varied rocks, but their folded, fractured structure leaves deposits scattered and hard to reach. India’s mineral wealth is therefore concentrated in the old plateaus of the peninsula.
16.2.2 The Three Mineral Belts
Within the peninsula the deposits crowd into three great mineral belts, each with its own character.
The first and richest is the north-eastern plateau belt, running across the Chota Nagpur plateau in Jharkhand, the Odisha plateau and the eastern Andhra plateau. It carries iron ore, manganese, mica, bauxite, limestone and copper, along with the atomic minerals uranium and thorium. Crucially, coal lies close by, in the Damodar valley and Chhattisgarh. Because rich iron ore and coal sit within haulage distance of each other, most of India’s integrated iron and steel plants have grown up in this belt.
The second is the south-western plateau belt, over the Karnataka plateau and the adjoining parts of Tamil Nadu. It holds large reserves of iron ore, manganese and bauxite, some non-metallic minerals, and almost all of India’s gold, worked at Kolar and Hutti in Karnataka. Its weakness is that it has little coal, and so lacks a nearby source of cheap power.
The third is the north-western belt, following the Aravalli range through Rajasthan and reaching into Gujarat around the Gulf of Khambhat. The Aravallis yield non-ferrous metals — copper, lead, zinc and silver — while Gujarat and the seas just off its coast supply petroleum and natural gas.
Beyond these three, a scattered Himalayan belt carries copper, lead, zinc, cobalt and tungsten, and mineral oil is drawn from the Assam valley and from offshore fields near Mumbai.
Map
Map 16.1 Caption: India’s three mineral belts, all set on the old peninsular plateaus and their margins. Brief: Political outline map of India showing the full extent of the country as officially defined by the Government of India, including Jammu and Kashmir and Ladakh, with international boundaries as officially recognised. Shade and label the three mineral belts — the north-eastern plateau belt (Chota Nagpur, Odisha, eastern Andhra), the south-western plateau belt (Karnataka and adjoining Tamil Nadu), and the north-western belt (Aravalli range in Rajasthan into Gujarat). Mark the northern plains and Himalayas as mineral-poor. Include a key. Do not show grades or quantities.
16.3 Iron Ore
Iron ore is the raw material of iron and steel, and steel is the frame on which modern life is built — its rails, girders, machines, ships and tools. A country’s appetite for iron is so closely tied to its development that the iron a nation consumes is often taken as a rough measure of its standard of living. India is fortunate: it holds some of the world’s largest and richest iron-ore reserves.
16.3.1 The Varieties Of Iron Ore
Iron ore is not one thing. Ores differ in how much iron they hold, and the more iron packed into the rock, the more valuable it is. Four varieties are commonly recognised, from richest to poorest.
Magnetite is the finest ore, black in colour, magnetic, and carrying about 70 per cent iron or more. Haematite is reddish and holds roughly 60 to 70 per cent iron; although a shade poorer than magnetite, it is the ore India actually mines most, because its deposits are enormous and easy to work. Limonite, yellow or light brown, carries only 40 to 60 per cent iron. Siderite is the poorest, riddled with impurities and yielding just 40 to 50 per cent iron.
Notice the lesson from the last section at work here. Magnetite is the best grade, yet it is not the one we mine most — the sheer abundance and accessibility of haematite matter more than its slightly lower iron content.
16.3.2 Production And Distribution
India’s iron-ore output has grown enormously since independence — from about 4 million tonnes in 1950-51 to roughly 192 million tonnes in 2016-17, and higher still since. Almost all of it comes from four states, all lying in the mineral belts of the peninsula.
Odisha is by far the largest producer, raising more than half of the national total. Its chief mining districts lie in the north of the state — Keonjhar, Mayurbhanj and Sundargarh. Chhattisgarh comes second, with its most important mines at Bailadila in the Bastar region of the south, and at Dalli-Rajhara. Karnataka is third, its leading centre being the Hospet–Bellary tract in the east, with more ore from the Bababudan hills of Chikmagalur and from Chitradurga. Jharkhand is fourth, mining chiefly in Singhbhum in the east of the state. Smaller quantities come from Maharashtra (Chandrapur), Goa, Andhra Pradesh, Tamil Nadu (Salem) and Madhya Pradesh (Balaghat).
The concentration is easier to grasp as a table.
The figures come from the Indian Mineral Yearbook. Read down the share column and one fact stands out: a single state, Odisha, produces more than the other three leading states put together. It is worth working out exactly how large that share is.
More than half of India’s iron ore comes from a single state. That concentration is efficient — Odisha’s ore lies close to coal, railways and eastern ports — but it is also a risk. When those mines slow down, whether from a heavy monsoon, a court order or a change in mining leases, the shortage reaches every steel plant and export terminal that depends on them. Distribution is never only about where a mineral is found; it is about how much of the nation’s supply rests on one place.
16.3.3 Uses And Trade
Nearly all iron ore goes to the same place: the blast furnace, where it is smelted into pig iron and then steel. Small amounts of ferrous minerals like manganese and chromite are added to make special steels — harder, tougher or rust-resistant. From this steel come the machines, buildings, vehicles and instruments of an industrial economy, which is why iron ore is called the foundation of modern industry.
India does not use all it digs. It is one of the world’s leading exporters of iron ore, shipping high-grade lumps chiefly to the steel mills of Japan, South Korea and China. Much of Chhattisgarh’s Bailadila ore, for instance, travels by rail to the port of Vishakhapatnam and on to Japan. Other iron-ore ports are Paradip in Odisha, Mormugao in Goa and New Mangalore in Karnataka.
This raises a genuine question of policy. Exporting raw ore earns foreign currency now, but the ore is finite, and the same ore turned into steel at home would earn far more and support more jobs. A country rich in ore must therefore weigh quick export earnings against keeping its best ore for its own future industry — a choice between selling the crop and milling the flour.
16.4 Mica
If iron ore is the metal of the machine age, mica is one of the quiet minerals that made electricity safe to use. It is easy to overlook — soft, flaky and dull — yet for a long time India supplied most of the world’s high-grade mica, and much of that came from a single famous belt.
16.4.1 Properties And Uses
Mica is a non-metallic, inorganic mineral with one unusual trick: it splits into thin, almost transparent, flexible sheets that peel apart like the pages of a book. This ability to be cleaved into fine, even films is the key to its usefulness.
What makes mica valuable is what it does with electricity. It is an excellent insulator — a material that does not let electricity pass through. Mica can resist very high voltage without breaking down, wastes very little energy as heat, and withstands heat itself. That combination makes it prized in the electrical and electronic industry, in capacitors, heating elements and countless small components.
Three types are found in India. Muscovite, pale and silvery, is the most valued and the best insulator; phlogopite is amber-brown; biotite is dark, almost black. Mica has been used in India since ancient times — in Ayurveda it is known as abhrak — but its modern importance rests almost entirely on electrical insulation.
For decades nothing could replace it. Then plastics and synthetic mica were developed, and the picture changed.
16.4.2 Production And Distribution
India was once almost the sole supplier of fine sheet mica to the world, and it still holds large reserves. The best mica grows in pegmatites — very coarse igneous rocks in which unusually large crystals form. These mica-bearing pegmatites occur chiefly in four states: Andhra Pradesh, Rajasthan, Jharkhand and Bihar.
Andhra Pradesh is by far the largest producer today, raising the overwhelming share of India’s output. Its mica belt lies in Nellore district, on the coast in the south-east of the state.
Rajasthan’s mica-bearing belt runs about 322 km from Jaipur to Udaipur across the east of the state, at its widest near Bhilwara, which is its leading centre. More mines lie at Jaipur, Tonk, Sikar and Ajmer.
The most famous mica belt of all is the older Koderma belt. It stretches from Gaya in central Bihar into Koderma and Hazaribagh in northern Jharkhand. This belt earned India its world reputation for high-quality ruby muscovite, though its output today is small beside that of Andhra Pradesh. In Bihar, Gaya remains the main producing district. Much of the mica in this belt is dug by small, informal operations rather than large mechanised mines.
16.5 Extraction And Its Consequences
A mineral in the ground is not yet wealth. It becomes wealth only when someone decides to dig it up, and that decision depends on far more than the mineral itself. And once the digging begins, it changes the land and the lives around it. This section looks at what makes a deposit worth mining, what mining does to the economy, and why a finite resource must be used with care.
16.5.1 Factors Affecting Exploitation
Not every deposit becomes a mine. A mineral is worth extracting only when a whole set of conditions line up, and together they decide whether a deposit is left alone or opened up.
The first condition is the ore itself — its grade and the size of the deposit. Rich ore in a large body repays the cost of mining; thin, scattered ore usually does not.
The second is how the mineral sits in the ground. Ore near the surface can be taken in open-cast pits, cheaply and quickly. Ore lying deep must be reached by underground tunnels, which are slow, costly and dangerous.
The third is reach and support. A deposit far from roads, railways and ports, or without nearby power, water, capital and labour to work it, may not be worth mining even when the ore is good.
The last is demand and permission. Mining goes ahead only where a market will pay more than the ore costs to extract, and where the law and environmental clearances allow it. Put all these together as a chain of questions.
Flowchart
Fig. 16.5-1 Caption: The chain of questions that decides whether a mineral deposit is left alone or opened as a mine. Nodes: A deposit is discovered → Is the ore rich enough (high grade)? no → leave it; yes → Is the deposit large enough to repay the cost? no → leave it; yes → Can it be reached and transported (roads, rail, ports)? no → leave it; yes → Are power, water, capital and labour available? no → leave it; yes → Will the market pay more than it costs to mine? no → leave it; yes → Do the law and clearances allow it? no → leave it; yes → the deposit becomes a working mine
16.5.2 Mining And The National Economy
Where mining does go ahead, it reshapes the national economy — for good and for ill.
On the gains side, minerals feed the country’s core industries: iron and steel, aluminium, cement, fertiliser and power all begin at a mine. Mining creates jobs and brings roads, railways and townships to remote regions. Exports of ore earn foreign exchange, while royalties and taxes on mining add to government revenue.
But the costs are heavy. Mining scars the land, strips away forest, and fouls air and water with dust and waste rock. Many of India’s mineral belts lie in forested, thinly populated uplands, so opening a mine can displace the communities living there. And because minerals are exhaustible, a region built on a single mine faces decline once the ore runs out.
The gains and the costs rarely fall on the same people, which is why mining so often divides opinion.
16.5.3 Conserving A Finite Resource
Because minerals cannot be regrown, using them wisely is a national concern. Conservation does not mean leaving minerals untouched in the ground; it means making each tonne go further.
Several things help. Ore can be mined and processed with less waste. Low-grade ore that was once ignored can be used as technology improves. Scrap metal can be recycled instead of smelting fresh ore. Alternatives can replace scarce minerals where possible, and illegal, wasteful mining can be curbed. Land that has been mined out can be filled in and replanted rather than left as a wound.
None of this makes minerals renewable. It only stretches a finite gift further, so that the ‘robber industry’ takes a little less than it might.
16.6 Energy Resources: The Broad Divisions
Power, or energy, is the primary input of a modern economy — the thing needed at the very start of making almost anything. Factories, farms, transport, homes and offices all run on it, and a country’s wheels of progress turn only as fast as its supply of energy allows. Before looking at India’s energy sources one by one, it helps to see how they are grouped, because the groupings shape the rest of this chapter.
Energy sources are classified in two different ways, and the two schemes cut across each other.
The first scheme asks whether the source runs out. Non-renewable energy comes from sources that took millions of years to form and are exhausted far faster than they can be replaced — coal, petroleum, natural gas and the nuclear minerals uranium and thorium. Renewable energy comes from sources that are continually replenished and never run dry — sunlight, wind, running water, tides, the Earth’s inner heat and living plant matter.
The second scheme asks how long-established the use is. Conventional energy covers the sources people have relied on for a long time and know well: coal, petroleum, natural gas, and the electricity made from them, together with hydro and nuclear power. Non-conventional energy covers the newer sources still being developed on a large scale: solar, wind, tidal, geothermal and biomass energy.
The important point is that these two schemes do not line up. A source can be renewable yet conventional, like hydroelectricity, or non-renewable yet conventional, like coal, or renewable and non-conventional, like solar. One source, two labels.
Diagram
Fig. 16.6-1 Caption: Every energy source carries two labels at once — one for whether it runs out, one for how established its use is. Brief: A two-by-two classification matrix. Horizontal axis labelled conventional (left column) to non-conventional (right column); vertical axis labelled non-renewable (top row) to renewable (bottom row). Place the sources in their quadrants: top-left (conventional, non-renewable) — coal, petroleum, natural gas, nuclear; bottom-left (conventional, renewable) — hydroelectricity; bottom-right (non-conventional, renewable) — solar, wind, tidal, geothermal, biomass; top-right (non-conventional, non-renewable) — left empty. Emphasise with a note that the same source sits in one box but reads off two axes.
One more distinction matters in a country like India. Commercial energy is bought and sold — coal, oil, electricity — while non-commercial energy is gathered rather than purchased, such as fuelwood, dried cattle dung and crop residues. Non-commercial fuels still meet much of the energy need in rural areas, though their share falls as living standards rise and the countryside turns to commercial power.
16.7 Coal
Coal has been called the mainstay of India’s power and the backbone of its heavy industry, and for good reason: well over half the commercial energy the country uses still comes from coal. The story of how coal forms was told at the opening of this chapter; here we look at its grades, where it lies in India, and what it does — and cannot do — for the economy.
16.7.1 The Origin And Grades Of Coal
Coal forms from plant matter buried and slowly compressed over millions of years, as the chapter opener described and Fig. 16.0-1 showed. The longer and harder the heat and pressure act, the more the carbon is concentrated — and the more carbon a coal holds, the better it burns. Coal is graded by that carbon content, from highest to lowest.
Anthracite is the finest grade, hard and jet-black with a semi-metallic shine, holding over 80 per cent carbon. It gives the most heat and burns with a clean, short blue flame. But it is rare in India, found only in Jammu and Kashmir, and in small quantity.
Bituminous coal holds roughly 60 to 80 per cent carbon. It is the workhorse — the most widely used coal by far — because it has a high calorific value (the heat given off when a fuel burns) and can be turned into coke and gas as well as burnt for steam. Most of it lies in Jharkhand, Odisha, West Bengal, Chhattisgarh and Madhya Pradesh.
Lignite, or brown coal, is a lower grade — softer, brownish, and heavy with moisture, so it crumbles and can even catch fire on its own if left in the open. India’s main lignite comes from Neyveli in Tamil Nadu, with more at Palana in Rajasthan. Peat is the lowest grade of all, the very first stage of coal, so full of moisture that it burns like wood, with much smoke and ash.
Notice again that the best grade is not the one we depend on. Anthracite is finest but scarce; bituminous coal, a step below, does nearly all the work.
16.7.2 Gondwana And Tertiary Coalfields
India’s coal belongs to two very different ages, and geologists sort the coalfields accordingly.
The Gondwana coalfields hold coal about 250 million years old. They contain roughly 98 per cent of India’s reserves and yield almost all of its output, including nearly all of its superior and coking coal. The coal lies sealed in the rift valleys of certain rivers — valleys where the crust was pulled apart and a block sank down. The chief ones follow the Damodar (Jharkhand and West Bengal), the Mahanadi (Chhattisgarh and Odisha), the Son (Madhya Pradesh) and the Godavari and Wardha (Maharashtra and Telangana). True anthracite is generally absent from these fields.
The Tertiary coalfields carry much younger coal, only 15 to 60 million years old, found in the extra-peninsular fringes of the country — Assam, Meghalaya, Arunachal Pradesh, Nagaland, and parts of Jammu and Kashmir, Rajasthan and Tamil Nadu. This coal has low carbon and a high content of moisture and sulphur, which limits its use.
Map
Map 16.2 Caption: India’s coalfields, split between the old Gondwana fields of the peninsular river valleys and the younger Tertiary fields of the fringes. Brief: Political outline map of India showing the full extent of the country as officially defined by the Government of India, including Jammu and Kashmir and Ladakh, with international boundaries as officially recognised. Mark the main Gondwana coalfields along the river valleys — Jharia, Bokaro and Raniganj (Damodar), Korba and Talcher (Mahanadi), Singrauli (Son), Singareni (Godavari). Mark Tertiary coalfields in the north-east (Assam, Meghalaya). Mark lignite at Neyveli. Include a key distinguishing Gondwana coal, Tertiary coal and lignite.
16.7.3 Production And Distribution
India’s coal output has climbed steeply since independence, from about 32 million tonnes in 1950-51 to over 700 million tonnes in recent years. The country also holds enormous reserves — about 352 billion tonnes (Geological Survey of India, 2021). Almost all of this coal comes from a cluster of eastern and central states.
Jharkhand, Chhattisgarh and Odisha are the leading producers. Jharkhand’s fields include Jharia — India’s chief source of coking coal — along with Bokaro, Ramgarh and Karanpura. Chhattisgarh’s output centres on Korba, and Odisha’s on Talcher. Beyond these, Madhya Pradesh mines at Singrauli and Sohagpur, Telangana at the Singareni fields of the Godavari valley, Maharashtra at Chandrapur in the Chanda-Wardha belt, and West Bengal at Raniganj, where Indian coal mining first began.
16.7.4 Coal In India’s Industrialisation
Coal is sometimes called ‘black gold’, and the name fits. It is the fuel of India’s thermal power stations, and it feeds the industries that build a modern economy — iron and steel, cement, fertiliser and chemicals. Most of the coal India mines goes to just two places: power generation and heavy industry.
But coal has real limitations. Most Indian coal is high-ash, non-coking coal, good for power stations but not for making steel. The special coking coal that a steel plant needs is scarce in India, so even a coal-rich country must import it.
A second limitation is location. India’s coal lies overwhelmingly in the east and centre, while power plants and factories are spread across the whole country, including the far west and south. Coal must therefore be hauled vast distances by rail, which strains the railways and adds cost. Mining itself is hazardous, too — roofs collapse, poisonous gases gather, and some fields, such as Jharia, have had underground fires smouldering for decades.
So when we ask why a coal-rich India still imports fuel, part of the answer is already here: the country is short of the coking coal its steel needs. The larger part of the answer — its heavy dependence on imported oil — comes in the next section.
16.8 Petroleum And Natural Gas
If coal powered the age of steam and steel, petroleum powers the age of the engine. Almost every vehicle on the road, the sea and the sky runs on it, and a vast chemical industry is built from it. Yet India, so rich in coal, is poor in oil — and that single fact shapes much of the country’s economy and its trade.
16.8.1 The Occurrence Of Oil
Petroleum, meaning ‘rock oil’, is a liquid fossil fuel formed from the remains of tiny marine organisms that sank to the sea floor, were buried in sediment, and were slowly cooked by heat and pressure over millions of years. It forms in the younger, Tertiary sedimentary rocks, not in the old crystalline rocks of the peninsula.
Oil does not gather in underground lakes. Once formed, it seeps upward through porous rock until it meets a layer of impermeable rock that stops it, and there it collects. Very often the trap is an up-fold in the rock, an anticline, where natural gas floats on top, oil settles below it, and water lies at the bottom.
So oil is found only in sedimentary basins that have both the right rocks and the right traps. India has about 1.7 million sq km of such basins, some on land and some offshore, out on the shallow continental shelf beneath the sea.
Diagram
Fig. 16.8-1 Caption: Oil and gas gather in the crest of an up-fold, sealed beneath a layer of rock they cannot pass through. Brief: A cross-section through an anticline (an up-fold in the rock layers). Show a porous reservoir rock (sandstone) capped by an impermeable rock layer. Within the reservoir, layer from top to bottom: natural gas, then oil, then water. Draw a well drilled down into the crest of the fold, passing through the cap into the gas and oil. Label the cap rock (impermeable), reservoir rock (porous), gas, oil, water, and the fold crest. Show, with a small arrow, that oil and gas rose until the cap rock trapped them.
16.8.2 The Oil-Producing Regions
Commercial oil is drawn from five regions of India.
The oldest is the north-eastern region, in the Upper Assam valley and reaching into Arunachal Pradesh and Nagaland. Its heart is Digboi, where oil was struck in 1889 and which still produces today — the oldest oilfield in India. Nearby fields include Naharkatiya and Moran.
The Gujarat region works the Cambay basin, its leading field being Ankleshwar, with more at Kalol, Nawagam and Mehsana.
The most important region of all is Mumbai High, an offshore field in the Arabian Sea about 176 km north-west of Mumbai. It was discovered in the mid-1970s and drilled from a floating platform called Sagar Samrat; its oil and gas are piped to the mainland at Uran. The Bassein field lies just to its south.
The Rajasthan region centres on the Barmer basin, where the large Mangala field was discovered in 2004, making Rajasthan a major inland producer. Finally, the east-coast region works the offshore Krishna-Godavari and Cauvery basins, the newest of India’s oil provinces.
Map
Map 16.3 Caption: India’s oil and gas fields ring the country’s margins, where the young sedimentary basins lie. Brief: Political outline map of India showing the full extent of the country as officially defined by the Government of India, including Jammu and Kashmir and Ladakh, with international boundaries as officially recognised. Mark the oil and gas regions: Upper Assam (Digboi, Naharkatiya), the Gujarat–Cambay basin (Ankleshwar, Kalol, Mehsana), Mumbai High offshore in the Arabian Sea, the Barmer basin in Rajasthan, and the offshore Krishna-Godavari and Cauvery basins on the east coast. Shade the main sedimentary basins and mark the fields. Include a key distinguishing oilfields, gas fields and sedimentary basins.
16.8.3 Natural Gas
Natural gas is a gaseous fossil fuel found either together with oil, as associated gas, or on its own in separate gas fields. It burns more cleanly than coal or oil, giving fewer pollutants for the same heat.
India’s gas comes from Mumbai offshore, the Cambay basin, the Rajasthan fields near Jaisalmer, and above all the Krishna-Godavari basin off the Andhra coast, where a large discovery was made in 2002. The gas is put to a wide range of uses: it generates power, is the raw material for fertiliser (urea), and is bottled as LPG for cooking and compressed as CNG for vehicles.
Because gas has to travel by pipe, its spread depends on a pipeline network. The long Hazira-Vijaipur-Jagdishpur (HBJ) pipeline carries gas across the country, and the Gas Authority of India Limited, set up in 1984, manages much of the transport and distribution.
16.8.4 A Dependence On Imports
India’s oil story has one hard fact at its centre: the country cannot pump nearly as much oil as it burns. Domestic production has stayed modest, while demand has climbed steeply with more vehicles, more industry and more people. The gap is filled by imports — India today buys over 85 per cent of the crude oil it uses, chiefly from West Asia and Russia.
That dependence costs a great deal. The import bill runs into lakhs of crores of rupees each year, and it rises and falls with world oil prices, so a jump in the global price of crude strains the whole economy. This is petroleum’s central limitation for India: however useful oil is, the country does not have enough of its own.
16.9 Generating Power In India
India makes most of its electricity in three ways — thermal, hydel and nuclear — and they share one final step. Each spins a turbine, a wheel driven by a moving fluid, which turns a generator, a machine that converts spinning motion into electric current. What the three differ in is how they spin that turbine, and where in the country they can be built.
16.9.1 Thermal Power
Thermal power is electricity made by burning fuel — coal, oil, natural gas or lignite — to boil water into steam, and using that steam to spin the turbine. It is by far the largest source of India’s electricity, supplying around three-quarters of the power from utilities. Its share grew rapidly after the National Thermal Power Corporation (NTPC) was set up in 1975 to build large stations.
The chain that turns fuel into current is the same one that runs a nuclear station, and it is worth seeing all three side by side.
Flowchart
Fig. 16.9-1 Caption: Three ways to spin a turbine — thermal and nuclear differ only in the heat source, while hydel needs no heat at all. Nodes: Thermal path: burn coal, oil or gas → heat → boil water into steam → spins the turbine; Nuclear path: split uranium by fission → heat → boil water into steam → spins the turbine; Hydel path: falling or flowing water → spins the turbine directly (no burning, no steam); all three paths → the turbine drives a generator → electricity
Because thermal plants burn coal, most are built where coal is cheap — beside the eastern coalfields such as Korba, Singrauli, Talcher and the Damodar valley — or near ports and gas fields, or close to big cities that need the power. A thermal plant also needs plenty of water for cooling. Its great advantages are that coal is abundant and a station can be built almost anywhere fuel can be brought; its drawbacks are that the fuel is exhaustible and burning it pollutes, a cost the next section takes up.
16.9.2 Hydroelectric Power
Hydroelectric, or hydel, power uses falling or flowing water to spin the turbine directly — no fuel is burnt and no steam is raised. It is renewable, clean and, once the dam is built, very cheap to run. Development began early, with a small station at Darjeeling in 1897 and another at Sivasamudram on the Kaveri in 1902, and expanded through the great multipurpose river projects — Bhakra-Nangal on the Sutlej, Koyna in Maharashtra, Hirakud on the Mahanadi and many more. The National Hydro-Electric Power Corporation (NHPC) was formed in 1975.
Four conditions must be met for a hydel plant to work. There must be a perennial flow of a large volume of water; the water must fall from a sufficient height, whether over a natural waterfall or a head created by a dam; there must be a nearby market, because electricity cannot easily be stored; and there must be heavy capital, since dams are very expensive to build.
These conditions explain why the potential is concentrated in the north. The Himalayan rivers are fed by glaciers and snow, so they flow all year, fall through steep dissected terrain, and carry about three-fourths of India’s hydel potential — the Brahmaputra basin the most, then the Indus, then the Ganga’s tributaries. The peninsular rivers, fed only by the monsoon, run high in the rains and low the rest of the year, so they need storage dams to yield steady power.
16.9.3 Nuclear Power
Nuclear power spins the turbine by the same steam route as thermal power, but its heat comes not from burning fuel but from fission — the splitting of heavy uranium atoms, which releases enormous heat (the nuclear path in Fig. 16.9-1). It is a conventional source, yet a small one, supplying under 3 per cent of India’s electricity.
India’s atomic programme began with the Atomic Energy Commission, set up in 1948 under Homi Bhabha, and grew from the research establishment at Trombay, later renamed the Bhabha Atomic Research Centre (BARC) in 1967. The country’s first nuclear station came up at Tarapur, near Mumbai, in 1969. Others followed: Rawatbhata near Kota in Rajasthan, Kalpakkam and Kudankulam in Tamil Nadu, Narora in Uttar Pradesh, Kaiga in Karnataka and Kakrapar in Gujarat.
Several factors shape where nuclear power can grow. It needs nuclear fuel — India has only modest uranium, mined chiefly at Jaduguda in Jharkhand, but very large reserves of thorium in the monazite sands of the southern coasts. It needs heavy water, huge capital, advanced technology, abundant cooling water, and strict safety — which is why many stations stand on the coast. Nuclear power matters most in regions far from the coalfields, such as the south and west, where thermal fuel is dear.
Map
Map 16.4 Caption: India’s nuclear power stations, most of them on or near the coasts and away from the eastern coalfields. Brief: Political outline map of India showing the full extent of the country as officially defined by the Government of India, including Jammu and Kashmir and Ladakh, with international boundaries as officially recognised. Mark and label the nuclear power stations — Tarapur (Maharashtra), Rawatbhata/Kota (Rajasthan), Kalpakkam and Kudankulam (Tamil Nadu), Narora (Uttar Pradesh), Kaiga (Karnataka), Kakrapar (Gujarat). Optionally show major thermal stations clustered near the eastern coalfields. Include a key distinguishing nuclear and thermal stations.
16.10 The Environmental Cost Of Energy
Every unit of energy carries a hidden price that never appears on the bill: its cost to the environment. Some sources charge more than others, and the conventional fossil fuels charge the most. Understanding these costs is the reason the world is now turning to cleaner sources.
Burning Fossil Fuels
The heaviest cost comes from burning coal, oil and gas — in power stations, vehicles and factories. Combustion releases carbon dioxide, sulphur dioxide, oxides of nitrogen and particulate matter — tiny solid particles small enough to be breathed deep into the lungs, measured as PM10 and PM2.5 by their size in micrometres. Together these foul the air of cities and countryside alike, harm human health, and fall as acid rain that damages soil, water and buildings.
Carbon dioxide does something further. It is a greenhouse gas — a gas that traps heat radiating from the Earth and warms the atmosphere. As fossil fuels are burnt in ever greater amounts, the extra carbon dioxide is warming the planet and shifting its climate, the process called global warming.
Coal brings two special problems. Burning it in thermal plants leaves fly ash — the very fine ash carried up with the flue gases — in enormous quantities, which pollutes land, air and water unless it is captured and put to use in cement, bricks or road embankments. And thermal and nuclear stations draw in river or sea water to cool their machinery and return it warm, causing thermal pollution: the heated water holds less dissolved oxygen, which harms the fish and other life in the river or along the coast.
The Cost Of The Dam
Hydroelectric power is often called clean, and its running does not pollute. But building it is not free of harm. A large dam floods a great stretch of land behind it, drowning forests and farmland, and the villages that stood there. The people living in the reservoir’s path lose their homes and land and must move elsewhere. The dam also blocks the river’s flow, traps its silt, and disrupts the fish and the life downstream.
The Risk In The Reactor
Nuclear power emits little pollution when it runs normally, but it carries a rarer, graver risk. An accident or leak at a reactor can spread radiation over a wide area, as the Chernobyl disaster of 1986 showed the world. Nuclear power also leaves radioactive waste that stays dangerous for a very long time and must be stored with great care. The danger is small in probability but large in consequence, which is why nuclear power is watched so closely.
These costs — a warming climate, dirty air, drowned valleys, radioactive waste — are the reason the search for cleaner energy has become urgent. That search is the subject of the final section.
16.11 Non-Conventional Sources Of Energy
The conventional sources are running down and dirtying the air and water as they go. So India, like the rest of the world, is developing non-conventional sources — the sun, the wind, the tides, the Earth’s heat and living matter — that never run out and pollute far less. Five stand out.
16.11.1 Bio-Mass And Biogas
Biomass is energy drawn from organic matter — wood, crop residues and animal dung. Its most useful form in rural India is biogas, a fuel made by fermenting cattle dung, crop waste or human waste in a sealed tank without air. The fermentation gives off a methane-rich gas that is burnt for cooking and lighting, and leaves behind a slurry that is rich manure.
India’s rural potential here is enormous, with abundant cattle dung and crop waste, and a national programme has set up millions of family-sized biogas plants. Biogas gives villages a smokeless cooking fuel, cuts the felling of trees for firewood, and improves sanitation by putting waste to use.
Its limits are practical. A plant needs a steady supply of dung or waste to run, some households are reluctant to use plants fed on human waste, and the small, scattered units need regular upkeep.
16.11.2 Solar Energy
Sunlight is put to use in two ways: as heat, in solar water-heaters and cookers, and as electricity, through photovoltaic cells — devices that turn sunlight directly into current. Being a tropical country, India receives strong sunshine for most of the year, except in the cloudy monsoon and the northern hills.
The potential is greatest in the clear, sunny stretches of Rajasthan, Gujarat and Ladakh. Solar street lights, water pumps and home lighting systems already reach across the country, and a Solar Cities programme helps towns raise their use of solar power.
Solar energy is inexhaustible, clean and free of fuel cost, and because it works off the grid it is ideal for remote villages. But it works only in daylight and clear weather, so it needs batteries to store power for the night; the initial cost is high, and large solar parks take up a great deal of land.
16.11.3 Wind Energy
Moving air spins large turbines that drive generators, turning wind into electricity. India has one of the larger wind potentials in the world, harnessed mainly in Tamil Nadu, Gujarat, Maharashtra, Karnataka and Rajasthan, along windy coasts and hill gaps.
Wind power is clean, renewable and needs no fuel. But the wind is intermittent, so power comes only while it blows; it needs particular windy sites, a wide spread of land, and a high initial investment.
16.11.4 Tidal Energy
The daily rise and fall of the sea can be turned into power. A barrage — a barrier built across a river mouth — holds back the incoming tide and then releases it, and the water flowing in and out drives turbines set in the barrage.
India’s tidal potential lies where the tidal range, the difference in water level between high and low tide, is greatest: the Gulf of Khambhat and the Gulf of Kachchh in Gujarat, and the Sundarbans in West Bengal.
Tidal energy is renewable, clean and unusually predictable, since the tides follow a fixed timetable. But very few coasts have a large enough tidal range, the cost is very high, and a barrage disturbs the delicate life of an estuary. For all these reasons India has mapped the potential but built almost nothing yet.
16.11.5 Geothermal Energy
Geothermal energy is heat drawn from within the Earth. In a few places that heat reaches the surface as hot springs or steam, which can warm buildings or drive a turbine to make electricity.
In India the potential is modest and still largely experimental. It centres on hot springs such as Manikaran in Himachal Pradesh and the Puga valley in Ladakh, where small pilot units have been tried.
Its great merit is that, unlike sun and wind, it is continuous — the Earth’s heat does not stop at night. But suitable hot-spring sites are few, drilling deep is expensive, and the technology is not yet widely developed in the country.
16.11.6 The Case For Renewables
Why should a country push these newer sources when coal is so cheap? Because the fossil fuels are finite and polluting; because heavy oil imports leave the economy exposed; because the climate is warming; and because sun and wind can light the remote villages that the grid struggles to reach. For a land as sunny and windy as India, the case is strong.
The main obstacle is the high initial cost, which a developing country finds hard to meet, together with some social reluctance — to biogas from human waste, for instance. Overcoming these needs cooperative effort and steady support from policy. Renewables are far cleaner than fossil fuels, though not wholly without impact: solar and wind parks take land, and tidal barrages alter estuaries. Even so, their share of India’s energy is climbing.
16.12 Summary
A mineral is a natural substance with a fixed chemistry and fixed properties; an ore is a mineral rich enough in metal to be worth mining. Minerals are either metallic (ferrous or non-ferrous) or non-metallic (organic fossil fuels or inorganic minerals).
All minerals share three traits: they are spread unevenly, high-grade ore is scarcer than low-grade ore, and they are exhaustible — mining takes a crop that never grows back, which is why it is called a ‘robber industry’.
Minerals form only in particular rocks, so India’s mineral wealth lies in the old crystalline plateaus of the peninsula, not under the deep alluvium of the northern plains. It gathers into three belts — the north-eastern, south-western and north-western.
Iron ore comes in four grades; magnetite is the richest, but haematite, though a shade poorer, is mined most because it is abundant and easy to work. Odisha alone raises over half of India’s output, almost all of it bound for steel.
Mica is prized as an electrical insulator. Andhra Pradesh, at Nellore, is the largest producer today, though the older Koderma belt of Jharkhand and Bihar made India’s name in mica. Demand fell once plastics and synthetics could replace it.
A deposit is mined only when grade, size, access, infrastructure, market and law all line up. Mining feeds industry and earns revenue, but it scars land, displaces communities and exhausts a finite resource — so minerals must be used with care.
Energy sources are classified two ways that cross-cut each other: renewable or non-renewable, and conventional or non-conventional. Coal is non-renewable but conventional; hydro is renewable and conventional; solar is renewable and non-conventional.
Coal is graded by carbon: anthracite is finest but rare, bituminous is the workhorse. India’s coal is mostly old Gondwana coal in the eastern river valleys — abundant overall, yet short of the coking coal that steel plants need.
Petroleum forms in young sedimentary basins and is trapped in up-folds beneath cap rock. India works five oil regions, with Mumbai High the chief, but produces far too little and imports over 85 per cent of its crude oil.
India makes electricity mainly by thermal power (about three-quarters), then hydel and nuclear. Thermal and nuclear raise steam to spin a turbine; hydel uses falling water directly. Hydel’s share fell as thermal grew far faster.
Every energy source carries an environmental cost: fossil fuels bring air pollution, global warming, fly ash and thermal pollution; large dams submerge land and displace people; nuclear power carries the rare but grave risk of radiation.
The non-conventional sources — biomass, solar, wind, tidal and geothermal — are clean and inexhaustible, and India’s sun and wind potential is large. But high cost and intermittency keep coal dominant for now, even as renewables rise.
Flowchart
Fig. 16.12-1 Caption: The arc of the whole chapter — from the rock in the ground to the power in the wire, and on to a cleaner future. Nodes: Geological processes form minerals and fossil fuels inside particular rocks → the deposits lie unevenly, concentrated in peninsular India → a deposit is mined only where grade, size, access, market and rules allow → minerals such as iron ore and mica feed industry, while fossil fuels feed energy → electricity is generated by the thermal, hydel and nuclear routes → every source carries an environmental cost → which drives the search for cleaner, non-conventional energy (solar, wind, tidal, geothermal, biomass)
What This Chapter Cannot Tell You
The national and state figures used here hide what lies inside them: a state’s share of iron ore or coal says nothing about which single district does the mining, or what that mining means for the people and forests around it. Production shares are snapshots that shift from year to year, and reserve figures are careful estimates, not exact counts of what lies underground. The chapter shows where minerals and energy are, and how much — but the human and ecological detail of any one mine, field or dam has to be studied on the ground.
16.13 Key Terms
Alluvium — fine sand, silt and clay laid down by rivers, which buries the bedrock beneath the northern plains.
Anthracite — the finest grade of coal, hard and jet-black, with over 80 per cent carbon and the highest heat value.
Barrage — a dam-like barrier built across a river mouth to harness the flow of the tides for power.
Biogas — a methane-rich fuel made by fermenting dung, crop waste or human waste in the absence of air.
Biomass — energy obtained from organic matter such as wood, crop residues and animal dung.
Bituminous coal — the most widely used grade of coal, holding roughly 60 to 80 per cent carbon.
Calorific value — the amount of heat given off when a fuel is burnt.
Commercial energy — energy that is bought and sold, such as coal, oil and electricity.
Conventional energy — the long-established sources of energy: coal, petroleum, natural gas, and hydro and nuclear power.
Crystalline rocks — hard igneous and metamorphic rocks made of interlocking crystals, forming the ancient peninsular plateau.
Exhaustible resources — resources that, once used, are gone and cannot be replaced within human time.
Ferrous minerals — metallic minerals that contain iron, such as iron ore, manganese and chromite.
Fission — the splitting of heavy atoms such as uranium, which releases large amounts of heat.
Fly ash — the very fine ash carried up with the flue gases when coal is burnt in a thermal plant.
Fossil fuels — energy minerals formed from the buried remains of plants and animals: coal, petroleum and natural gas.
Generator — a machine that converts spinning motion into electric current.
Geothermal energy — energy drawn from the heat within the Earth, reaching the surface as hot springs or steam.
Gondwana coalfields — India’s older coalfields, about 250 million years old, holding most of its reserves and superior coal.
Greenhouse gas — a gas, such as carbon dioxide, that traps heat radiating from the Earth and warms the atmosphere.
Insulator — a material that does not let electricity pass through it.
Lignite — a low grade of coal, brown and high in moisture, also called brown coal.
Metallic minerals — minerals that yield a metal when smelted, such as iron ore, copper and bauxite.
Mica — a non-metallic mineral that splits into thin, flexible sheets and is a fine electrical insulator.
Mineral — a naturally occurring substance with a definite chemical composition and definite physical properties.
Natural gas — a gaseous fossil fuel found with oil or on its own, which burns more cleanly than coal or oil.
Non-commercial energy — energy that is gathered rather than bought, such as fuelwood, cattle dung and crop residues.
Non-conventional energy — the newer sources being developed: solar, wind, tidal, geothermal and biomass energy.
Non-ferrous minerals — metallic minerals that contain no iron, such as gold, copper, bauxite and lead.
Non-metallic minerals — minerals that hold no metal to extract, such as mica, limestone and coal.
Non-renewable energy — energy from sources that took ages to form and are used up far faster than they form.
Ore — a mineral or rock that holds enough metal, in workable form, to be mined at a profit.
Particulate matter — tiny solid particles in the air, small enough to be breathed deep into the lungs.
Peat — the lowest grade of coal, the first stage of its formation, full of moisture.
Pegmatites — very coarse igneous rocks in which unusually large crystals, including mica, grow.
Petroleum — a liquid fossil fuel, ‘rock oil’, formed from marine organisms buried in sedimentary rocks.
Photovoltaic — describing a cell that turns sunlight directly into electricity.
Renewable energy — energy from sources that are continually replenished and never run out.
Rift valleys — valleys formed where the crust was pulled apart and a block sank down, in which Gondwana coal lies.
Tertiary coalfields — India’s younger coalfields, 15 to 60 million years old, low in carbon and high in moisture and sulphur.
Tidal range — the difference in water level between high tide and low tide.
Turbine — a wheel spun by a moving fluid, steam or water, that drives a generator.
16.14 Points to Ponder
If the richest ore is always mined first, can a nation that looks resource-rich today be sure it will still be resource-rich for its grandchildren?
India exports raw iron ore, yet imports coking coal and most of its oil. Is it wiser to sell a mineral we hold in plenty, or to hold it back for industries we have not yet built?
Anthracite and magnetite are the finest grades of coal and iron ore, yet we mostly use bituminous coal and haematite. What does it say about resources that the best is so seldom the most useful?
A place cannot choose the rocks that lie beneath it. If minerals decide where mines, factories and power stations grow, how much of a region’s fortune is geography rather than effort?
Coal is cheap, reliable and Indian; sun and wind are clean but dearer and come and go. If both the climate and the cost matter, how fast should a country switch, and on what should that pace depend?
A dam can water and power millions while drowning the homes of a few thousand. When a project’s gains and losses fall on different people, what would you need to know to judge whether it was worth building?
16.15 Objective Questions
- Which is the richest variety of iron ore? [1 mark]
- Haematite
- Magnetite
- Limonite
- Siderite
- Which state is the largest producer of iron ore in India? [1 mark]
- Jharkhand
- Chhattisgarh
- Odisha
- Karnataka
- Which of the following is a non-ferrous mineral? [1 mark]
- Manganese
- Chromite
- Bauxite
- Iron ore
- The oldest oilfield of India is: [1 mark]
- Mumbai High
- Ankleshwar
- Digboi
- Barmer
- Which source supplies the largest share of India’s electricity? [1 mark]
- Hydel
- Nuclear
- Thermal
- Solar
- Which grade of coal has the highest carbon content? [1 mark]
- Lignite
- Peat
- Bituminous
- Anthracite
- Assertion (A): The northern plains of India are poor in minerals. Reason (R): Thick alluvium covers and conceals the mineral-bearing bedrock of the plains.
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true. [1 mark]
- Assertion (A): The share of hydroelectricity in India’s power has fallen since independence. Reason (R): The installed capacity of hydroelectric power has decreased over the years.
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true. [1 mark]
- Match each place in Column A with the mineral it is known for in Column B. [1 mark]
| Column A | Column B |
|---|---|
| a. Bailadila | i. Mica |
| b. Nellore | ii. Lignite |
| c. Digboi | iii. Iron ore |
| d. Neyveli | iv. Petroleum |
- Fill in the blanks: (i) The ore from which aluminium is obtained is ______. (ii) The splitting of heavy atoms that produces heat in a nuclear reactor is called ______. [1 mark]
16.16 Check Your Concepts
Define an ore, and state how it differs from a mineral. [2 marks]
State the three characteristics common to all minerals. [2 marks]
Name the four varieties of iron ore in decreasing order of iron content. [2 marks]
Differentiate between ferrous and non-ferrous minerals, giving one example of each. [3 marks]
Give reasons why India still imports most of its petroleum even though it holds vast reserves of coal. [3 marks]
Why is haematite mined far more than magnetite, even though magnetite is the richer ore? [3 marks]
Explain the four conditions necessary for the development of hydroelectric power, with reference to India. [4 marks]
Evaluate the claim that hydroelectricity is a completely clean and harmless source of energy. [4 marks]
Describe the origin, grades and distribution of coal in India, and explain why a coal-rich country must still import coking coal. [6 marks]
Discuss the potential and the limitations of the non-conventional sources of energy in India, and explain the need to promote them. [6 marks]
16.17 Map, Diagram & Data Interpretation
On an outline map of India, locate and label the following: (a) the Digboi oilfield; (b) Mumbai High; (c) a nuclear power station lying south of the Tropic of Cancer; (d) the Raniganj coalfield. [4 marks]
Study Fig. 16.8-1, the oil trap. (a) Name the three layers found in the reservoir, from top to bottom. (b) Explain why the oil does not simply escape to the surface. (c) Which of the three would a well drilled into the crest reach first? [3 marks]
With reference to Fig. 16.9-1, state in what way thermal and nuclear power generation are alike, and how hydel generation differs from both. [3 marks]
Study Table 16.1. (a) Which state produced the most iron ore, and what was its share of the all-India total? (b) Calculate the combined share of Chhattisgarh and Karnataka. (c) State one thing the table does not tell you about the ore mined. [4 marks]
Suppose a state produced 45,000 thousand tonnes of coal in a year, out of an all-India total of 6,00,000 thousand tonnes. Using the method shown in the chapter, calculate the state’s percentage share of national production. Show your working. [2 marks]