CLASS-
VIII RESOURCES AND DEVELOPMENTS
03. MINERAL AND POWER
RESOURCES
MINERALS
· A
naturally occurring substance that has a definite chemical composition is a
mineral.
· They
are concentrated in a particular area or rock formations.
· Some
minerals are found in areas which are not easily accessible such as the Arctic
ocean bed and Antarctica.
· Minerals
are formed in different types of geological environments, under varying conditions.
They are created by natural processes without any human interference.
· They
can be identified on the basis of their physical properties such as colour,
density, hardness and chemical property such as solubility.
TYPES OF MINERALS
· There
are over three thousand different minerals. On the basis of composition,
minerals are classified mainly as metallic and non-metallic minerals.
· Metallic
minerals contain metal in raw form. Metals are hard substances
that conduct heat and electricity and have a characteristic lustre or shine.
Iron ore, bauxite, manganese ore are some examples.
· Metallic
minerals may be ferrous or non-ferrous. Ferrous minerals like iron ore,
manganese and chromites contain iron. A non-ferrous mineral does not contain
iron but may contain some other metal such as gold, silver, copper or lead.
· Non-metallic
minerals do not contain metals. Limestone, mica and gypsum are examples of such
minerals. The mineral fuels like coal and petroleum are also non-metallic
minerals.
MINING
· Minerals
can be extracted by mining, drilling or quarrying. The process of taking out
minerals from rocks buried under the earth’s surface is called mining.
· Minerals
that lie at shallow depths are taken out by removing the surface layer; this is
known as open-cast mining.
· Deep
bores, called shafts, have to be made to reach mineral deposits that lie at
great depths. This is called shaft mining.
· Petroleum
and natural gas occur far below the earth’s surface. Deep wells are bored to
take them out, this is called drilling (Fig 3.4).
· Minerals
that lie near the surface are simply dug out, by the process known as quarrying.
DISTRIBUTION
OF MINERALS
· Minerals
occur in different types of rocks. Some are found in igneous rocks, some in
metamorphic rocks while others occur in sedimentary rocks.
· Generally,
metallic minerals are found in igneous and metamorphic rock formations that
form large plateaus. Iron-ore in north Sweden, copper and nickel deposits in
Ontario, Canada, iron, nickel, chromites and platinum in South Africa are
examples of minerals found in igneous and metamorphic rocks.
· Sedimentary
rock formations of plains and young fold mountains contain non-metallic
minerals like limestone. Limestone deposits of Caucasus region of France,
manganese deposits of Georgia and Ukraine and phosphate beds of Algeria are
some examples. Mineral fuels such as coal and petroleum are also found in the
sedimentary strata.
ASIA
· China
and India have large iron ore deposits.
· The
continent produces more than half of the world’s tin.
· China,
Malaysia and Indonesia are among the world’s leading tin producers.
· China
also leads in production of lead, antimony and tungsten.
· Asia
also has deposits of manganese, bauxite, nickel, zinc and copper.
EUROPE
· Europe
is the leading producer of iron-ore in the world.
· The
countries with large deposits of iron ore are Russia, Ukraine, Sweden and
France.
· Minerals
deposits of copper, lead, zinc, manganese and nickel are found in eastern
Europe and European Russia.
NORTH
AMERICA
· The
mineral deposits in North America are located in three zones: the Canadian
region north of the Great Lakes, the Appalachian region and the mountain ranges
of the west.
· Iron
ore, nickel, gold, uranium and copper are mined in the Canadian Shield Region,
coal in the Appalachians region.
· Western
Cordilleras have vast deposits of copper, lead, zinc, gold and silver.
SOUTH
AMERICA
· Brazil
is the largest producer of high grade iron-ore in the world.
· Chile
and Peru are leading producers of copper. Brazil and Bolivia are among the
world’s largest producers of tin.
· South
America also has large deposits of gold, silver, zinc, chromium, manganese,
bauxite, mica, platinum, asbestos and diamond.
· Mineral
oil is found in Venezuela, Argentina, Chile, Peru and Columbia.
AFRICA
· It
is the world’s largest producer of diamonds, gold and platinum.
· South
Africa, Zimbabwe and Zaire produce a large portion of the world’s gold. The
other minerals found in Africa are copper, iron ore, chromium, uranium, cobalt
and bauxite.
· Oil
is found in Nigeria, Libya and Angola.
AUSTRALIA
· Australia
is the largest producer of bauxite in the world.
· It
is a leading producer of gold, diamond, iron ore, tin and nickel.
· It
is also rich in copper, lead, zinc and manganese.
· Kalgoorlie
and Coolgardie areas of western Australia have the largest deposits of gold.
ANTARCTICA
· Significant
size of deposits of coal in the Transantarctic Mountains and iron near the
Prince Charles Mountains of East Antarctica is forecasted.
· Iron
ore, gold, silver and oil are also present in commercial quantities.
DISTRIBUTION
IN INDIA
· Iron:
India has deposits of highgrade iron ore. The mineral is found mainly in
Jharkhand, Odisha, Chhattisgarh, Madhya Pradesh, Goa, Maharashtra and
Karnataka. Bauxite: Major bauxite producing areas are Jharkhand, Odisha,
Chhattisgarh, Madhya Pradesh, Gujarat, Maharashtra and Tamil Nadu.
· Mica:
Mica deposits mainly occur in Jharkhand, Bihar, Andhra Pradesh and Rajasthan.
India is the largest producer and exporter of mica in the world. Copper: It is
mainly produced in Rajasthan, Madhya Pradesh, Jharkhand, Karnataka and Andhra
Pradesh.
· Manganese:
India’s manganese deposits lie in Maharashtra, Madhya Pradesh, Chhattisgarh,
Odisha, Karnataka and Andhra Pradesh.
· Limestone:
Major limestone producing states in India are Bihar, Jharkhand, Odisha, Madhya
Pradesh, Chhattisgarh, Rajasthan, Gujarat and Tamil Nadu. Gold: Kolar in
Karnataka has deposits of gold in India. These mines are among the deepest in
the world which makes mining of this ore a very expensive process.
· Salt:
It is obtained from seas, lakes and rocks. India is one of the world’s leading
producers and exporters of salt.
USES
OF MINERALS
· Copper
is another metal used in everything from coins to pipes.
· Silicon,
used in the computer industry is obtained from quartz.
· Aluminum
obtained from its ore bauxite is used in automobiles and airplanes, bottling
industry, buildings and even in kitchen cookware.
CONSERVATION
OF MINERALS
· Minerals
are a non-renewable resource.
· It
takes thousands of years for the formation and concentration of minerals.
· The
rate of formation is much smaller than the rate at which the humans consume
these minerals.
· It
is necessary to reduce wastage in the process of mining.
· Recycling
of metals is another way in which the mineral resources can be conserved.
POWER RESOURCES
· With
the advent of science and technology the life styles are changing very fast. Power or energy plays a vital role in
our lives.
· We
also need power for industry, agriculture, transport, communication and
defense. Power resources may be broadly categorised as conventional and
non-conventional resources.
Conventional
Sources
· Conventional
sources of energy are those which have been in common use for a long time.
Firewood and fossil fuels are the two main conventional energy sources.
Firewood
· It
is widely used for cooking and heating. In our country more than fifty per cent
of the energy used by villagers comes from fire wood.
· Remains
of plants and animals which were buried under the earth for millions of years
got converted by the heat and pressure into fossil fuels.
· Fossil
fuel
such as coal, petroleum and natural gas are the main sources of conventional
energy.
Coal
· This
is the most abundantly found fossil fuel.
· It
is used as a domestic fuel, in industries such as iron and steel, steam engines
and to generate electricity. Electricity from coal is called thermal power.
· The
coal which we are using today was formed millions of years ago when giant ferns
and swamps got buried under the layers of earth. Coal is therefore referred to
as Buried Sunshine.
· The
leading coal producers of the world are China, USA, Germany, Russia, South
Africa and France.
· The
coal producing areas of India are Raniganj, Jharia, Dhanbad and Bokaro in
Jharkhand.
Petroleum
· The
petrol that keeps your car running as well as the oil that keeps your cycle
from squeaking, both began as a thick black liquid called Petroleum.
· It
is found between the layers of rocks and is drilled from oil fields located in
off-shore and coastal areas. This is then sent to refineries which process the
crude oil and produce a variety of products like diesel, petrol, kerosene, wax,
plastics and lubricants.
· Petroleum
and its derivatives are called Black Gold as they are very valuable.
· The
chief petroleum producing countries are Iran, Iraq, Saudi Arabia and Qatar. The
other major producers are USA, Russia, Venezuela, and Algeria.
· The
leading producers in India are Digboi in Assam, Bombay High in Mumbai and the
deltas of Krishna and Godavari rivers.
Natural
Gas
· Natural
gas is found with petroleum deposits and is released when crude oil is brought
to the surface. It can be used as a domestic and industrial fuel.
· Russia,
Norway, UK and the Netherlands are the major producers of natural gas.
·
In India Jaisalmer, Krishna Godavari delta,
Tripura and some areas off shore in Mumbai have natural gas resources.
Hydel
Power
·
The falling water flows through pipes
inside the dam over turbine blades placed at the bottom of the dam. The moving
blades then turn the generator to produce electricity. This is called hydro
electricity.
· The
water discharged after the generation of electricity is used for irrigation.
One fourth of the world’s electricity is produced by hydel power.
· The
leading producers of hydel power in the world are Paraguay, Norway, Brazil,
andChina.
· Some
important hydel power stations in India are Bhakra Nangal, Gandhi Sagar,
NagarjunSagar and Damodar valley projects.
NON-CONVENTIONAL
SOURCES OF ENERGY
· The
increasing use of fossil fuels is leading to its shortage. It is estimated that
if the present rate of consumption continues, the reserves of these fuel will
get exhausted. Moreover, their use also causes environmental pollution.
Therefore, there is need for using non-conventional sources such as solar energy,
wind energy, tidal energy which are renewable.
Solar
Energy
· Sun’s
heat and light energy can be felt by us every day. Solar energy trapped from
the sun can be used insolar cells to produce electricity. Many of these cells
are joined into solar panels to generate power for heating and lighting
purpose.
· Solar
energy is also used in solar heaters, solar cookers, solar dryers besides being
used for community lighting and traffic signals.
Wind
Energy
· Wind
is an inexhaustible source of energy. Wind mills have been used for grinding
grain and lifting water since times immemorial. In modern time wind mills, the
highspeed winds rotate the wind mill which is connected to a generator to
produce electricity.
· Wind
farms having clusters of such wind mills are located in coastal regions and in
mountain passes where strong and steady winds blow. Windfarms are found in
Netherlands, Germany, Denmark, UK, USA and Spain are noted for their wind
energy production.
Nuclear
Power
· Nuclear
power is obtained from energy stored in the nuclei of atoms of naturally
occurring radio active elements like uranium and thorium. These fuels undergo
nuclear fission in nuclear reactors and emit power.
· The
greatest producers of nuclear power are USA and Europe.
· In India Rajasthan and Jharkhand have
large deposits of Uranium. Thorium is found in large quantities in the Monozite
sands of Kerala.
· The
nuclear power stations in Indiaare located in Kalpakkam in Tamilnadu, Tarapur
in Maharastra, Ranapratap Sagar near Kota in Rajasthan, Narora in Uttar Pradesh
and Kaiga in Karnataka.
Geothermal
Energy
· Heat
energy obtained from the earth is called geothermal energy. The temperature in
the interior of the earth rises steadily as we go deeper.
· Some
times this heat energy may surface itself in the form of hot springs. This heat
energy can be used to generate power.
· Geothermal
energy in the form of hot springs has been used for cooking, heating and
bathing for severalyears.
· USA
has the world’s largest geothermal power plants followed by New Zealand,
Iceland, Philippines and Central America.
· In
India, geothermal plants are located in Manikaran in Himachal Pradesh and Puga
Valley in Ladakh.
TIDAL
ENERGY
· Energy
generated from tides is called tidal energy. Tidal energy can be harnessed by
building dams at narrow openings of the sea.
· During
high tide the energy of the tides is used to turn the turbine installed in the
dam to produce electricity.
· Russia,
France and the Gulf of Kachchh in India have huge tidal mill farms.
BIOGAS
· Organic
waste such as dead plant and animal material, animal dung and kitchen waste can
be converted into a gaseous fuel called biogas.
· The
organic waste is decomposed by bacteria in biogas digesters to emit biogas
which is essentially a mixture of methane and carbon dioxide.
· Biogas
is an excellent fuel for cooking and lighting and produces huge amount of
organic manure each year.
· Energy
is everywhere but we can see that harnessing this energy is both difficult as
well as costly. Each one of us can make a difference by not wasting energy.
Energy saved is energy generated.
……...the end………
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