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Chapter
44 Earth’s Resources
Renewable and Nonrenewable Resources
4.1 Energy and Mineral Resources
Renewable resources can be replenished over fairly short spans of time, such as months, years, or decades.
Nonrenewable resources take millions of years to form and accumulate.
Fossil Fuels
4.1 Energy and Mineral Resources
Fossil fuels are hydrocarbons that may be used as fuel, including coal, oil, and natural gas.
Fossil Fuels-Coal
4.1 Energy and Mineral Resources
The Basics:o Formed when heat and pressure transform
plant material over millions of years o Four stages of development: peat, lignite,
bituminus coal, anthraciteo Used to generate electricity and production of
steelo Surface mines vs underground mines vs
mountaintop removal
Fossil Fuels-Coal
4.1 Energy and Mineral Resources
ADVANTAGES:• Plentiful
– In US, can provide about 450 years
• Cheap• Electricity• Versatile• Many Jobs!
DISADVANTAGES• Dirty
– Acid rain from the sulfur when burning coal
– Releases greenhouse gases
• Inefficient – About 30% efficient
from coal electricity
Fossil Fuels-Petroleum & Natural Gas
4.1 Energy and Mineral Resources
The Basics:o Formed from remains of plants and animals
that were buried in ancient seaso Formation begins when large quantities of
remains become buried in ocean floor sediments, over millions of years chemical rxns slowly tranform some of the organic remains into the liquid and gas forms
o Oil Traps: geologic structure that allows large amounts of fluids to accumulate; stops upward movement of oil and gas
Fossil Fuels-Petroleum & Natural Gas
4.1 Energy and Mineral Resources
Oil Traps All have 2 things in common
Permeable reservoir rock Allows oil and gas to collect in large
quantities Cap rock
Near impenetrable and so keeps oil and gas from escaping to surface
Anticline is an uparched series of sedimentary rock layers
Anticlines Are Common Oil Traps
Fossil Fuels-Petroleum
4.1 Energy and Mineral Resources
ADVANTAGES:• Plentiful• Easy to transport
because liquid• Relatively
inexpensive
DISADVANTAGES• Carbon emissions• Recovery process not
efficient enough• Drilling endangers the
environment and ecosystem
• Spills
Fossil Fuels-Natural Gas
4.1 Energy and Mineral Resources
ADVANTAGES:• Burns cleaner than
coal and oil• Inexpensive• 70% less CO2 than
other fossil fuels
DISADVANTAGES• Inability to recover all
in-place gas from producible deposit
• Lack of technology
Tar Sands and Oil Shale
4.1 Energy and Mineral Resources
Fuels derived from tar sand and oils shales could become good substitutes for dwindling petroleum supplies.
Tar sands: mixtures of clay and sand combined with water and varying amounts of black, thick tar called bitumen Cant be pumped out easily Requires lots of water Can lead to pollution in toxic disposal ponds inefficient
Oil Shale
4.1 Energy and Mineral Resources
Oil Shale Rock that contains waxy mixture of hydrocarbons
called kerogen Half of worlds supply in Green River Formation in
Colorado, Wyoming, and Utah
Formation of Mineral Deposits
4.1 Energy and Mineral Resources
Some of the most important mineral deposits form through igneous processes and from hydrothermal solutions. • Ore is a useful metallic mineral that can be
mined at a profit.
Mineral Resources and Igneous Processes
4.1 Energy and Mineral Resources
gold, silver, copper, mercury lead, platinum, and nickel just a few deposits produced by igneous processes
Hydrothermal Solutions
4.1 Energy and Mineral Resources
Hot water Hydrothermal deposits form from hot,
metal-rich fluids that are left during the last stages of movement and cooling of magma
Examples: gold deposit in South Dakota, lead, zinc, silver deposits in Idaho, Copper deposits in Michigan
Mineral-Rich Hot Water Seeps into Rock Fractures
Placer Deposits
4.1 Energy and Mineral Resources
Formed when eroded heavy minerals settle quickly from moving water while less dense particles remain suspended and continue to move
Usually involve minerals that are heavy but also durable and chemically resistant
Common sites: inside of bends in streams, cracks, depressions, and other streambed irregularities
Gold is best known
Nonmetallic Mineral Resources
4.1 Energy and Mineral Resources
Nonmetallic mineral resources are extracted and processed either for the nonmetallic elements they contain or for their physical and chemical properties.
Two main groups: building materials & industrial materials
Examples: aggregates, fluorite, fertilizers
Uses of Nonmetallic Minerals
Solar Energy
4.2 Alternate Energy Sources
1. Solar energy’s “fuel” is free. Solar energy has two advantages:
2. Solar energy is non-polluting.
1. Solar energy is not cheap! Solar energy has disadvantages:
2. Not always sunny-problems with battery/storage
3. Inefficient (10-20%)
Solar Energy
4.2 Alternate Energy Sources
o How some work:o Active Solar collector
o Roof mounted devices, collect heat from the sun that can be transferred to areas where it is needed by circulating air or liquids through piping
o Also used to heat water
Solar Energy
4.2 Alternate Energy Sources
o How some work:o Photovoltaic (solar) cells
o Convert sunlight’s energy into electricity
Nuclear Energy
4.2 Alternate Energy Sources
In nuclear fission, the nuclei of heavy atoms such as uranium-235 are bombarded with neutrons.
The uranium nuclei split into smaller nuclei and emit neutrons and heat energy.
Nuclear Energy
4.2 Alternate Energy Sources
ADVANTAGES:• No emissions• Fuel can be recycled• Inexpensive• Fairly abudnant
DISADVANTAGES• Potential of high risk
disaster• Where to put waste• Earthquakes can cause
damage and leaks at plants
• National Security issues• NON -RENEWABLE
Diablo Canyon Nuclear Plant
Wind Energy
4.2 Alternate Energy Sources
In the next 50 to 60 years, wind power could meet between 5 to 10 percent of the country’s demand for electricity.
Fastest growing alternate energy source
Wind Energy
4.2 Alternate Energy Sources
ADVANTAGES:• Abundant• Not many emissions
(still need steel that is produced from coal)
DISADVANTAGES• Unpredictable• Turbines may be
noisy• Space availability
Wind Turbines
Hydroelectric Power
4.2 Alternate Energy Sources
The strong water flow that results drives turbines and electric generators.
Negative effects: sedimentation, natural water flow, harms fish
We’ve built all the dams we can: 98% of US rivers are dammed
The water held in a reservoir behind a dam is a form of stored energy that can be released through the dam to produce electric power.
Hydroelectric power is the power generated by falling water.
Glen Canyon Dam
Geothermal Energy
4.2 Alternate Energy Sources
Hot water is used directly for heating and to turn turbines that generate electric power.
Iceland gets 100% of energy from geothermal
No harmful products, little maintenance after construction of plants
Can’t be built everywhere
Geothermal energy is harnessed by tapping natural underground reservoirs of steam and hot water.
The Geysers Is the World’s Largest Electrical Geothermal Facility
Tidal Power
4.2 Alternate Energy Sources
Tidal power is harnessed by constructing a dam across the mouth of a bay or an estuary in coastal areas.
The strong in-and-out flow of tidal water drives turbines and electric generators.
Tidal Dams
The Water Planet
4.3 Water, Air, and Land Resources
Each day, people use fresh water for drinking, cooking, bathing, and growing food.
Water covers 71% of the Earth’s surface<1% of water is usable fresh water
The Water Planet
4.3 Water, Air, and Land Resources
• Point source pollution comes from a known and specific location, such as factory pipes.
• Nonpoint source pollution is pollution that does not have a specific point of origin.
Freshwater Pollution
• Runoff is the water that flows over the land rather than seeping into the ground, often carrying nonpoint source pollution.
Water pollution can lead to birth defects, cancer, diseases, kill aquatic organisms and disrupt ecosystems
Major Types of Water Pollution
Earth’s Blanket of Air
4.3 Water, Air, and Land Resources
• The increase of carbon dioxide in the atmosphere has altered the carbon cycle and contributed to global warming—the unnatural warming of the lower atmosphere.
The chemical composition of the atmosphere helps maintain life on Earth.
• Through a series of chemical reactions, these pollutants in the air are converted into acids that are a major cause of acid precipitation.
Pollution in the Air
EPA estimates that as many as 200,000 deaths each year are associated with outdoor air pollution
Earth’s Blanket of Air
4.3 Water, Air, and Land Resources
•Burning of fossil fuels also produces Carbon Dioxide•Global Warming could result in big changes in Earth’s environment
These changes could include: melting glaciers, rise in sea level, flooding of coastal areas
•Chloroflurocarbons (CFCs) once used in air conditioners and plastic foam production destroy ozone in the stratosphere layer of the atmosphere
Could result in increased health problems like cataracts and skin cancer because more of the suns UV radiation would reach Earth’s surface
Major Primary Pollutants and Their Sources
Land Resources
4.3 Water, Air, and Land Resources
Earth’s land provides soil and forests, as well as mineral and energy resources
Damage to Land Resources• Mines produce many mineral resources, but
mines are destroying, soil, vegetation, and Earth’s contours.
• Mines also cause soil erosion and pollution that contaminates soil and water and destroys ecosystems.
Keeping Water Clean and Safe
4.4 Protecting Resources
Conservation is the careful use of resources.
Pollution prevention means stopping pollution from entering the environment.
Keeping Water Clean and Safe
4.4 Protecting Resources
Starting in the 1970’s, the federal government passed several laws to prevent or decrease pollution and protect resources.• In 1972, the Clean Water Act (CWA) required
industries to reduce or eliminate point source pollution into surface waters.
• The Safe Drinking Water Act of 1974 helped protect drinking resources.
Preventing Water Pollution
Protecting the Air
4.4 Protecting Resources
In the 1970’s, Congress passed the Clean Air Act, the nation’s most important air pollution law.• National Ambient Air Quality Standards (NAAQS)
established for six “criteria” pollutants known to cause health problems – carbon monoxide, ozone, lead, sulfur dioxide, nitrogen oxides and particulates (fine particles).
Saving Energy
Caring for Land Resources
4.4 Protecting Resources
Protecting land resources involves preventing pollution and managing land resources wisely.• Compost is partly decomposed organic material
that can be used as fertilizer.• Recycling is the collecting and processing of
used items so that they can be made into new products.
Recycling Facts
4.4 Protecting Resources
~425,000,000 tons of municipal waste per year
Average American produces 4.6 lbs of trash per day
US recycles about 1/3 of all waste~53% paper products recycled95% energy saved by recycling an
aluminum can compared with manufacturing a new one