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Chapter 5: Earth’s Energy and Mineral Resources
Faustina Academy
Earth Science
Section 1: Nonrenewable Energy Resources
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Energy
 ability to cause change
Nonrenewable energy resources
 energy resources used faster than natural processes can
replace them
Fossil fuels
 Coal, oil, natural gas
 Formed from remains of plants and other organisms buried and
altered over millions of years
Uses of Fossil Fuels
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Coal
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Generates electricity
Oil
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A.K.A. petroleum
Lubricant
Produces gasoline and other fuels, plastics, shingles, asphalt,
wax
Natural gas
 Heats buildings
 Source of sulfur
Coal
Rock containing at least 50% plant remains
Most abundant fossil fuel (pg. 121)
If the consumption of coal continues at current rate, coal supply will
last 250 years
Begins to form when plants die in swamp
Dead plants covered by plants, water, and sediment are not in contact
with oxygen, causing slow decay
Bacterial growth causes breakdown of molecules in plant tissue,
leaving carbon and some impurities behind, forming coal after millions
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of years
Bacteria also cause release of methane gas, carbon dioxide,
ammonia, and water
Hydrocarbons are extracted from coal to form liquid and gaseous
synthetic fuels
These liquid fuels can then be processed to produce gasoline for
automobiles and fuel oil for home heating
Gaseous synthetic fuels can be used to generate electricity and to
heat buildings
Stages of Coal Formation
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As decaying plant material loses gas and moisture, carbon becomes
concentrated, resulting in peat
Peat
 Layer of organic sediment containing water and impurities
 When peat is buried under more sediment, it changes into
lignite
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Soft brown coal with much less moisture
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Releases more energy and less smoke when burned
Bituminous coal
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Compact, black, brittle
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Provides lots of heat energy when burned
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Contains sulfur, a pollutant
Anthracite coal
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Forms if enough heat and pressure is applied
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Contains most carbon of all forms of coal and burns the cleanest
Oil and Natural Gas
Two other fossil fuels consisting of hydrocarbons, that provide large
quantities of energy
Oil
 Thick, black liquid
Natural gas
 Forms under similar conditions and often with oil, but forms in
gaseous state
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Petroleum
Forms over millions of years from remains of tiny marine organisms in
the ocean sediment
As plankton are deeply buried, temperature and pressure increase,
causing a change into oil and gas
Oil and natural gas are often found in layers of rock that have become
titled or folded (pg. 123)
Oil and natural gas are forced upward because they are less dense
than water
Rock layers that are impermeable, such as shale, stop this upward
movement and trap oil and natural gas
Reservoir rock
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Rock layer beneath shale in which petroleum and natural gas
accumulate
Removing Fossil Fuels From the Ground
Coal mining
 Strip mining
 Underground mining
Coal Mining
Strip mining
 Layers of soil and rock removed and piled
 Exposed coal removed and transported
 Used when coal is not deep
 Mining companies put dirt back, add topsoil, plant grass, trees,
and may reintroduce animals
Slope mining
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Angled opening and air shaft are made in the side of mountain
to remove coal
Removing Fossil Fuels From the Ground
Oil and natural gas are fossil fuels pumped from underground
deposits
Wells are drilled through rocks where these resources might be
trapped
 Reserve
 Amount of fossil fuel extracted at a profit using current
technology
 Resource
 Amount of fossil fuel extracted in useful amounts (but not
necessarily for a profit)
Methane Hydrates
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Methane
 Main component of natural gas
 Recent studies found new source of methane
Methane hydrates
 Stable molecules found hundreds of meters below sea level in
ocean floor sediment
Form under conditions of low temperature and high pressure
More carbon is contained in methane hydrates than in all current
fossil fuel deposits combined
Large supplies are thought to be off the eastern coast of the US
Highly flammable
Difficulties in removal
Conserving Fossil Fuels
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Fossils fuels
 Take millions of years to form
 Used much faster than Earth processes can replenish them
 Turning off lights, computers, TV's, etc., reduces fossil fuel waste
 Keeping doors and windows shut when AC is on
Energy From Atoms
Most electricity in US generated in power plants using fossil fuels
Nuclear energy
 Alternate energy source produced from atomic reactions
 When the nucleus of heavy element is split, lighter atoms form
and energy is released
 This energy can be used for electricity or to power submarines
Nuclear fission
 Splitting of heavy elements to produce energy
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Carried out in power plants using a type of uranium as fuel
Electricity From Nuclear Energy
Within a nuclear power plant, there is a large chamber called a
nuclear reactor
Within the nuclear reactor, uranium fuel rods sit in a pool of cooling
water
Neutrons are fired into fuel rods
When Uranium-235 atoms are hit, they break apart and fire out
neutrons that hit other atoms, beginning a chain reaction and
releasing a lot of heat energy
Heat is used to boil water to make steam, which drives a turbine that
turns a generator to produce electricity
Nuclear energy is a non-renewable energy source because it uses
U-235 as fuel
Nuclear Energy
Another problem with nuclear energy
 Waste material produced, radioactive elements that will remain
for thousands of years
This problem could be solved if useable energy could be obtained
from fusion
Fusion reaction
Source of the Sun's energy that is constantly occurring
Materials of low mass are fused together to form substance of higher
mass
Fusion of hydrogen and helium would be ideal
Hydrogen is in abundance in ocean water and the waste is much less
dangerous than from fission reactions
Scientists need to develop way to achieve high temperatures and high
pressure in order to perform a fusion reaction
Section 2: Inexhaustible Energy Resources
Will not run out in the future
Include sun, wind, water, and geothermal energy
Solar energy
 Energy from Sun
The sun's energy heats Earth and it causes circulation in Earth's
atmosphere (wind) and oceans (currents)
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Solar Energy
Solar energy can be used in an active or passive way
 Passive
 South-facing windows collect sunlight and warm the room
Active
 Solar collectors actively collect energy from sun and transform it
into electricity
Solar energy powers streetlights, calculators, even cars
Clean and inexhaustible
However, solar cells work less efficiently on cloudy days and cannot
work at night
Some systems use batteries to store solar energy for use at night or
cloudy days, but it's difficult to store energy in batteries
Wind Energy
Used to power sailing ships
Windmills used to pump water or grind corn
Wind farm
 Today wind turbines used to generate electricity
Few regions of the world have winds strong and steady enough to
produce electricity
Energy From Water
Hydroelectric energy
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Electricity produced by water power
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E.g., Dam is built to contain water
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As water is released it’s force turns turbines that turn generators
to make energy
Micro hydroelectric power
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Waterwheels used to grind grain or cut lumber
Geothermal energy
 Energy obtained by using hot magma or hot, dry rocks inside earth
(pg. 133)
 Water becomes steam when it is pumped through broken, hot, dry
rocks
 The steam is then used to turn turbines that run generators to make
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electricity
Hot dry rocks can be found almost anywhere
Renewable Energy Resources
Can be replaced in nature or by humans within a relatively short
period of time (within a human life span)
Biomass energy
 Energy derived from burning organic material such as wood,
alcohol, and garbage
 Major source of renewable energy
Energy from wood
Through burning, gives off stored solar energy as heat and light
energy
However, gases and small particles released when burned
Energy from Alcohol
Biomass fuel changed to alcohol (ethanol) and mixed with gas
(gasohol)
Gasohol used like gasoline
Reduces amount of fossil fuel needed
Problem: growing corn and distilling ethanol uses more energy than
amount received in ethanol
Energy From Garbage
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2/3 of what is thrown away could be burned
If more garbage used for fuel, more fossil fuels could be saved
Burning garbage is cheap source of energy and reduces landfills
However, burning garbage produces toxic ash residue and pollution
Metallic Mineral Resources
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Mineral resource
 A deposit of useful minerals
Metallic mineral resources
 Metals obtained from Earth materials
Ores
 Deposits in which a mineral(s) exists in large enough amounts to
be profitably mined
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Ores
To be an ore, the mineral must be in demand
Enough of it must be present to make it worth removing
Must be fairly easy to separate mineral from the material in which it is
found
Refining Ore
After metallic ore is mined from Earth's crust, it is crushed and the
waste rock (gangue) removed
Refining produces a pure or nearly pure substance from ore
E.g., iron can be concentrated from the ore hematite, composed of
iron oxide. The concentrated ore can then be purified through
smelting (pg. 138)
Smelting
Chemical process that removes impurities from metal
Chemical is added to iron ore and combines with oxygen, leaving
behind pure iron
During this process, a resource (fossil fuel) is used to get another
resource (iron)
Nonmetallic Mineral Resources
Mineral resources not used as fuels or as sources of metals
Can be divided into two groups
 Industrial minerals
 Building materials
Industrial Materials
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E.g., sandstone
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Source of silica, used to make glass
E.g., sylvite
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Used to make potassium fertilizer
E.g., halite
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Used to make salt
E.g., corundum and garnet
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Abrasives that can be glued to make sandpaper
Building Materials
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Aggregate
 One of the most important nonmetallic mineral resources
 Composed of crushed stone or a mixture of gravel and sand
 Can be mixed with cement and water to make concrete
Limestone
 Used as a paving stone and as part of concrete mixtures
Gypsum
 Soft, lightweight
 Used to make plaster and wallboard
Rock
 Used as building stone
 E.g., granite, limestone, sandstone
Recycling Mineral Resources
Mineral resources are nonrenewable
 Require millions of years to form
Recycling
 Using old materials to make new ones
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Reduces demand for new mineral resources
Uses less energy than it takes to obtain new material
Saves the material so we don't run out as soon
Important because most mineral resources are
imported