UNDERSTANDING EARTH’S
RESOURCES
Objectives
• Explain the difference between renewable and
nonrenewable resources.
• Identify four principal fossil fuels.
• Identify the sources of coal and petroleum.
• Identify the major alternative to fossil fuels.
• Define economic geology.
• Identify six ways in which minerals become
concentrated.
Renewable and nonrenewable
resources
• Natural resources and
ancient history
– Natural resource
• A useful material that is
obtained from the
lithosphere,
atmosphere,
hydrosphere, or
biosphere
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Renewable and nonrenewable
resources
• Renewable resource
– A resource that can be
replenished or regenerated
on the scale of a human
lifetime
• Nonrenewable resource
– A resource that cannot be
replenished or regenerated
on the scale of a human
lifetime
Energy Resources
• Resources and
modern society
– North America has the
highest per capita
usage of energy
resources.
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• Fossil fuel
Fossil Fuels
– Combustible organic matter
– Trapped in sediment or sedimentary rock
• Peat
– A biogenic sediment
– Accumulation and compaction of plant remains from bogs
and swamps
– Carbon content of about 25%
• Coal
– A combustible rock formed by the compression, heating,
and lithification of peat.
– 50-95% carbon
Fossil Fuels
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Lignite (low rank coal) in Tertiary sediments of North Dakota
Fossil Fuels
Fossil Fuels
• Petroleum
– Naturally occurring gaseous, liquid, and semi solid substances that
consist chiefly of hydrocarbon compounds
• Oil
– The liquid form of petroleum
• Natural gas
– The gaseous form of petroleum
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Fossil Fuels
Unconventional fossil fuels
• Tar sands
– A sediment or
sedimentary rock
in which the pores
are filled with
dense, viscous,
asphalt like oil
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Unconventional fossil fuels
• Oil shale
– A fine grained
sedimentary rock
with a high content
of kerogen
Fossil Fuels
• Relying on fossil fuels
– Most projections
indicate oil production
will peak and begin to
decrease before 2020.
– It will become
necessary to place
greater emphasis on
other sources of energy
besides fossil fuels
Renewable Energy Sources
• Power from sun, wind,
and water
– Solar energy is 10,000
times greater than the
sum of all human energy
demands… (much more
abundant than wind,
tidal, etc.)
– But the best available
solar cells are still too
costly and inefficient for
most uses
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Renewable Energy Sources
• Power from sun, wind, and
water
– Biomass energy
• Any form of energy that is
derived from plant life
• Includes fuel wood, peat,
animal dung, and agricultural
wastes, ethanol
– Wind turbines
• Still expensive, but likely that
their cost will soon be
competitive with the cost of
coal burning electric power
plants
Renewable Energy Sources
• Power from sun,
wind, and water
– Hydroelectric energy
• Electricity generated
by running water
– Hydrogen
• Can be used to power
fuel cells
• No place to mine
hydrogen (must be
converted from water,
which uses as much
energy as it produces)
Renewable Energy Sources
• Nuclear and geothermal
power
– Nuclear reactors explore the
energy-producing process
called radioactive decay
– Geothermal energy used by
humans come from
hydrothermal reservoirs,
• These are underground
systems of hot water or
steam
• They circulate in fractured or
porous rock
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Renewable Energy Sources
Temporary storage of
radioactive waste
Yucca Mountain-approved for
permanent storage in 2002, but
terminated in 2009.
Mineral Resources
• Ore
– A deposit from which one or more minerals can be extracted
profitably
• Finding and assessing mineral resources
– Nonrenewable, countries that can meet their need today may
not be able to in the future
– Uneven distribution of exploitable deposits mean no nation
is self sufficient
– Shift of mineral exploration and production away from the
industrialized nations toward less developed countries
Mineral Resources
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Mineral Resources
• How mineral deposits
are formed
–
–
–
–
–
–
Hydrothermal
Metamorphic
Magmatic
Sedimentary
Placer
Residual
Mineral Resources
Mineral Resources
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Mineral Resources
• Will we run out?
– Many geologist fear that shortages of
nonrenewable resources will hamper
development
– Shortages of energy resources are more likely to
affect us in the short run
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