Download Chapter 7-Resources and Energy

Chapter 7-Resources and Energy
Section 1 – Mineral Resources
Section 2 – Nonrenewable Energy
Section 3 – Renewable Energy
Section 4 – Resources and Conservation
Section 1 – Mineral Resources
More than 3,000 different minerals have been
identified in the Earth’s crust.
• Minerals can be metals (like gold) or nonmetals
(like sulfur)
– Metals can be identified by shiny surfaces and are
good conductors of heat and electricity.
– Nonmetals have a dull surface and are poor
conductors of heat and electricity.
• Native elements can exist in the earth’s crust as
nuggets of pure metal – gold, silver, and copper.
• Most other minerals are compounds of two or
more minerals.
• Ore is a mineral deposit from which metals and
nonmetals can be removed profitably.
• Ores are formed in a variety of ways
• Formed by cooling magma – as the magma cools,
dense metallic minerals sink and form layers at the
bottom of the magma chamber.
• Formed by contact metamorphism – Contact
metamorphism is a process that occurs when magma
comes into contact with existing rock. Heat and
chemical reactions with hot fluid from the magma can
change the composition of the surrounding rock,
forming ores. When many thick mineral veins form in a
relatively small region, the ore deposit is called a lode.
• Formed by moving water – water breaks down the
rock into fragments that are carried in the stream until
the current is too weak to carry the dense metals. The
fragments drop to the bottom of the stream beds
forming placer deposits.
• Uses of Mineral Resources – Some metals are prized
for their beauty and rarity like gold, platinum, and
silver. Rare nonmetallic minerals are called gemstones
and display extraordinary brilliance and color when
they are specially cut for jewelry. Some minerals are
used for building materials.
• Mineral Exploration and Mining – companies are often
looking for new areas to mine. Areas are tested before
mining to make sure they will be profitable.
– Subsurface mining – miners work underground to recover
mineral deposits.
– Surface mining – miners strip the metals from the surface
– Placer mining – mined by dredging rivers and streams
– Undersea mining – trying to find ways to mine undersea
Section 2 – Nonrenewable Energy
• Many of the Earth’s resources are used to
generate energy. Energy resources that exist in
limited amounts and cannot be replaced quickly
are called nonrenewable resources.
• Fossil fuels are nonrenewable resources formed
from the remains of living things. Examples are
coal, petroleum, and natural gas.
• The most commonly burned fuel is coal. Coal is
formed when dead plant material is buried in
swamp mud and becomes peat. Bacteria
consumes the peat and uses up all the oxygen.
Coal can only be formed where there is no
oxygen.
• Two types of coal
– Pressure and the weight of sediment causes the
peat to be compressed and it forms the coal called
bituminous coal. This is the most abundant type
of coal. It is made of 80% carbon.
– Under continued heat and pressure, bituminous
coal is changed to anthracite, the hardest form of
coal. Anthracite is made of 90% carbon.
• Both types release a large amount of heat
when they burn.
• Petroleum and natural gas are formed when
microorganisms and plants died in shallow
oceans or lakes. They become covered in
sediment. As more sediment covers it, heat and
pressure increases and converts the material into
petroleum and natural gas.
• Petroleum and natural gas are most commonly
found in permeable sedimentary rock. The liquid
rises up through the rock filling the spaces to
form the oil resevoir.
• Natural gas, petroleum and water are found in
layers in this order.
• Crude oil or unrefined petroleum are used in the
production of plastics, synthetic fabrics, waxes,
shampoo, medicines, insecticides, and fertilizers.
Nuclear Energy
• Nuclear energy is energy produced by
bombarding atoms and releasing the energy
that holds the atom together.
• The splitting of a large, heavy atom into two
or more smaller nuclei is called nuclear fission.
• The energy needed to hold an atom together
is more than 1 million times stronger than the
strongest chemical bonds between atoms.
• Nuclear energy is based on a chain reaction.
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