STD-X SS - Minerals and energy resources
A homogenous, naturally occurring substance with definable
internal structure is called mineral.
Types of Minerals
1.
Metallic
a.
Ferrous (containing
iron): Iron ore, manganese, nickel, cobalt, etc.
b.
Non-ferrous: Copper,
lead, tin, bauxite, etc.
c.
Precious: Gold, silver,
platinum, etc.
2.
Non-metallic: Mica,
salt, potash, sulphur, granite, limestone, marble, sandstone, etc.
3.
Energy Minerals: Coal,
petroleum and natural gas
Mode of occurrence of minerals:
- In
igneous and metamorphic rocks: The
smaller occurrences are called veins and the larger occurrences are called
lodes. They are usually formed when minerals in liquid/molten and gaseous
forms are forced upwards through cavities towards the earth’s surface.
Examples: tin, copper, zinc, lead, etc.
- In
sedimentary rocks: In these rocks, minerals
occur in beds or layers. Coal, iron ore, gypsum, potash salt and sodium
salt are the minerals found in sedimentary rocks.
- By
decomposition of surface rocks: Decomposition
of surface rocks and removal of soluble constituents leaves a residual
mass of weathered material which contains ores. Bauxite is formed in this
way.
- As
alluvial deposits: These minerals are found
in sands of valley floors and the base of hills. These deposits are called
placer deposits. They generally contain those minerals which are not
corroded by water. Examples; gold, silver, tin, platinum, etc.
- In
ocean water: Most of the minerals in
ocean water are too widely diffused to be of economic importance. But
common salt, magnesium and bromine are mainly derived from ocean waters.
6.
ron Ore
7. India is rich in good quality iron ores.
Magnetite is the finest iron ore with a very high content of iron upto 70%.
This iron ore is valuable for the electrical industry because of its excellent
magnetic properties. Hematite ore is the most important industrial iron ore; in
terms of usage. The iron content of hematite is 50-60%.
Major Iron
Ore Belts in India
- Orissa
Jharkhand Belt: Badampahar mines in the
Mayurbhanj and Kendujhar districts of Orissa have high grade hematite ore.
Additionally, hematite iron ore is mined in Gua and Noamundi in Singhbhum
district of Jharkhand.
- Durg
Bastar Chandrapur Belt: This
belt lies in Chhattisgarh and Maharashtra. The Bailadila range of hills in
the Bastar district of Chhattisgarh have very high grade hematite ore.
This hilly range has 14 deposits of super high grade hematite ore. Iron
from these mines is exported to Japan and South Korea via Vishakapatnam
port.
- Bellary
Chitradurga Chikmaglur Tumkur Belt: This
belt lies in Karnataka. The Kudremukh mines located in the Western Ghats
are a 100 percent export unit. The ore from these mines is transported as
slurry through a pipeline to a port near Mangalore.
- Maharashtra
Goa Belt: This belt inculdes the
state of Goa and Ratnagiri district of Maharashtra. The ores in these
mines are not of very high quality. They are exported through Marmagao
port.
Manganese
Manganese
is mainly used in the manufacturing of steel and ferro-manganese alloy. It is
also used in making bleaching powder, insecticides and paints.
opper
Copper is
mainly used in electrical cables, electronics and chemical industries. The
Balaghat mines in Madhya Pradesh produce 52% of India’s copper. Rajasthan is
the next leading producer with about 48% share. Copper is also produced in the
Singhbhum district of Jharkhand.
Aluminium
Aluminium
is lightweight yet strong and hence is used in a variety of applications.
Amarkantak plateau, Maikal hills and the plateau region of Bilaspur-Katni are
the main areas of bauxite deposits. Orissa is the leading producer of bauxite
in India with 45% share. Panchpatmali in Koraput district is the most important
centre of bauxite deposit in Orissa.
Mica
Mica is a
mineral which is made up of a series of plates or leaves. The mica sheets can
be so thin that a thousand of them can be layered into a few centimetre thick
mica sheet. Mica has excellent di-electric strength, low power loss factor,
insulating properties and resistance to high voltage. Mica is widely used in
electric and electronic industries.
Mica
deposits are found in the northern edge of the Chota Nagpur plateau.
Koderma-Gaya-Hazaribagh belt of Jharkhand is the leading producer of mica.
Ajmer in Rajasthan and Nellore in Andhra Pradesh are the other important
producers of mica.
Hazards of Mining
Mining is
a hazardous industry; both for the workers and for the residents. The Miners
have to work under tough conditions where no natural light is available. There
is always a risk of collapse of mine roof, inundation with water and fire. The
areas around mines face the problem of too much dust from the mines. Slurry
from mines damages the roads and the farmland. Houses and clothes become dirty
more often than in other areas. Miners are at great risk of getting afflicted
with pulmonary disorders. Cases of respiratory tract diseases are very high in
mining areas.
Conservation of Minerals
It takes
millions of years for the formation of minerals. Compared to the present rate
of consumption, the replenishment rate of minerals is very slow. Hence, mineral
resources are finite and non-renewable. Due to this, it is important that we
conserve the mineral resources.
Minerals and Energy Resources
Energy Resources
Conventional
Energy Resources: Firewood, cattle dung cake,
coal, petroleum, natural gas and electricity (both hydel and thermal)
Non-conventional
Energy Resources: Solar, wind, tidal,
geothermal, biogas and atomic energy.
Firewood
and cattle dung cake: As per estimates, more than
70% of energy need in rural households is met by firewood and cattle dung cake.
A decreasing forest area is making it difficult to use firewood. Dung cake can
be put to better use in the form of manure and hence its use should also be
discouraged.
1.
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