Download Nonrenewable Mineral Resources

Chapter 14
Nonrenewable Mineral Resources
Chapter Outline
Key Concepts
14-1A Dynamic processes within the earth and on its surface produce the mineral resources we depend
on.
14-1B Mineral resources are nonrenewable because they are produced and renewed over millions of years
mostly by the earth’s rock cycle.
14-2A Nonrenewable mineral resources exist in finite amounts and can become economically depleted
when it costs more than it is worth to find, extract, and process the remaining deposits.
14-2B There are several ways to extend supplies of mineral resources, but each of them is limited by
economic and environmental factors.
14-3 Extracting minerals from the earth’s crust and converting them into useful products can disturb the
land, erode soils, produce large amounts of solid waste, and pollute the air, water, and soil.
14-4 We can try to find substitutes for scarce resources, reduce resource waste, and recycle and reuse
minerals.
14-5 Dynamic processes move matter within the earth and on its surface and can cause volcanic
eruptions, earthquakes, tsunamis, erosion, and landslides.
Key Questions and Case Studies
CORE CASE STUDY: The crucial importance of rare-earth metals.
Few people have heard of rare-earth metals and oxides that are crucial to the major technologies that
support today’s lifestyles and economies. Without affordable supplies of rare-earth metals, industrialized
nations could not develop the current versions of cleaner energy technology and other high-tech products.
14-1 What are the earth’s major geological processes and what are mineral resources?
A. The earth is made up of a core, mantle, and crust and is constantly changing as a result of
processes taking place on and below its surface. Geology is the study of dynamic processes
occurring on the earth’s surface and in its interior.
B. Huge volumes of heated and molten rock moving around the earth’s interior form massive solid
tectonic plates that move extremely slowly across the earth’s surface. About 12 or so rigid
tectonic plates move across the surface of the mantle very slowly. These thick plates compose the
lithosphere.
C. The movement of these plates produces mountains on land and trenches on the ocean floor. The
movement of plates also produces earthquakes and volcanic action.
D. Some processes wear down the earth’s surface by moving topsoil and pieces of rock from one
place to another, while other processes build up soil on the earth’s surface. Weathering is the
physical, chemical, and biological processes that break down rocks and minerals into smaller
pieces.
E. The earth’s crust consists of minerals and rocks. A rock is a combination of one or more
minerals.
1. Sedimentary rock is made of sediment.
2. Igneous rock forms below the earth’s surface.
Instructor's Manual: Chapter 14
3. Metamorphic rock forms when preexisting rocks are subjected to high temperatures or
pressure.
4. The rock cycle is the interaction of physical and chemical.
F. Mineral resources are concentrations of naturally occurring materials that can be extracted and
processed.
1. Ore is a rock with a high concentration of a particular mineral. Can be high-grade, or lowgrade.
2. Reserves of minerals are identified resources from which the mineral can be extracted
profitably.
14-2 How long might supplies of nonrenewable mineral resources last?
A. The future supply of a resource depends on its affordable supply and how rapidly that supply is
used. A nonrenewable resource generally becomes economically depleted rather than totally
depleted. There are five choices at that point: recycle or reuse existing supplies, waste less, use
less, find a substitute, or do without.
B. A rising price for a scarce mineral resource can increase supplies and encourage more efficient
use. Economics determines what part of a known mineral supply is extracted and used. Higher
prices often mean more resources can be used (at a higher extraction cost), but this can be
affected by national policies that subsidize exploration or restrict exports/imports.
C. New technologies can increase the mining of low-grade ores at affordable prices, but harmful
environmental effects can limit this approach. In 1900, the average copper ore mined in the U.S.
was about 5% copper by weight; today that ratio is 0.5%.
D. Most minerals in seawater and on the deep ocean floor cost too much to extract, and there are
squabbles over who owns them. Rich hydrothermal deposits of gold, silver, zinc, and copper are
found as sulfide deposits in the deep-ocean floor and around hydrothermal vents. Another
potential source from the ocean floor is potato-sized manganese nodules that cover large areas of
ocean floor.
14-3 What are the environmental effects of using nonrenewable mineral resources?
A. The life cycle of a metal is very energy intensive.
B. There are many ways to extract minerals
1. Surface mining
2. Open pit mining
3. Strip mining
4. Contour strip mining
5. Mountaintop removal
6. Subsurface mining
a. Identified resources have a known location, quantity, and quality.
b. Reserves are identified resources that can be extracted profitably at current prices.
c. Undiscovered reserves are potential supplies of a mineral resource assumed to exist.
d. Other resources are undiscovered resources and identified resources not classified as
reserves.
C. Mining scars the land and produces large amounts of solid waste and air and water pollution. The
impacts include high costs (into the billions of dollars), subsidence, toxin and acid drainage,
toxics emission to the atmosphere.
CASE STUDY: The real cost of gold.
At about 90% of the world’s gold mines, the mineral is extracted using a highly toxic solution of
cyanide salts sprayed on piles of crushed rock. Cyanide is extremely toxic to birds and mammals
drawn to the ponds of water. Some mining companies have declared bankruptcy, which has allowed
them to walk away from clean-up.
Instructor's Manual: Chapter 14
D. After waste material is removed from metal ores they are smelted or treated with chemicals to
extract the desired metal. There can be enormous amounts of air and water pollution from these
processes.
14-4 How can we use mineral resources more sustainably?
A. Scientists and engineers are developing new types of materials that can serve as substitutes for
many metals. This is known as the materials revolution. For example, development of silicon and
ceramics may replace the need for as much metal.
SCIENCE FOCUS: The nanotechnology revolution.
Nanotechnology involves the manipulation of atoms and molecules to create materials. The
technology is very promising, but there are drawbacks. It is suggested that we carefully investigate
risks and develop guidelines and regulations until more is known about potentially harmful effects.
SCIENCE FOCUS: Graphene: a revolutionary material.
Graphene is made from graphite, which is pencil lead. It is one of the world’s thinnest and strongest
materials. China controls about 73% of the world’s high-purity graphite production.
B. Recycling valuable and scarce metals saves money and has a lower environmental impact than
mining and extracting them from their ores. In many cases, metals are actively recycled.
C. We can use mineral resources more sustainably by reducing their use and waste and by finding
substitutes with fewer harmful environmental effects.
14-5 What are the earth’s major geological hazards?
A. Volcanoes often form along the boundaries of tectonic plates. Eruptions can be very destructive.
B. Earthquakes are the release of energy accumulated over time along a fault.
1. Tsunamis can result from underwater earthquakes.
Key Terms
area strip mining
asthenosphere
contour strip mining
core
crust
depletion time
earthquake
geology
high-grade ore
igneous rock
lithosphere
low-grade ore
mantle
metamorphic rock
mineral
mineral resource
mountaintop removal
open-pit mining
ore
overburden
reserves
rock
rock cycle
sedimentary rock
smelting
spoils
strip mining
subsurface mining
surface mining
tectonic plates
tsunami
volcano
weathering
Suggested Responses to End of Chapter Questions
Review Questions
1. Core case study. Explain the importance of the rare-earth metals.
 Rare-earth metals are extremely important because they are used in many technologies. Without
affordable supplies of these metals, industrialized nations could not develop current versions of
Instructor's Manual: Chapter 14
cleaner energy technology and other high-tech products. Nations also need these metals to
maintain their military strength.
2. Section 14-1. What are the two key concepts for this section? Define geology, core, mantle,
asthenosphere, crust, and lithosphere. Define mineral, mineral resource, and rock. Define and
distinguish among sedimentary rock, igneous rock, and metamorphic rock and give an example of
each. Define and describe the nature and importance of the rock cycle. Define ore and distinguish
between a high-grade ore and a low-grade ore. List five important nonrenewable mineral resources
and their uses.
 Geology is the science devoted to the study of dynamic processes occurring on the earth’s surface
and in its interior.
 The core is the earth’s innermost zone. It is extremely hot and has a solid inner part, surrounded
by a liquid core of molten or semisolid material.
 Surrounding the core is a thick zone called the mantle, mostly solid rock.
 The outermost and thinnest zone of the earth is the crust.
 The asthenosphere is a zone of hot, partly melted rock under the rigid outermost part of the
mantle.
 The combination of the crust and the rigid, outermost part of the mantle is called the lithosphere.
 A mineral is an element or inorganic compound that occurs naturally in the earth’s crust as a solid
with a regular internal crystalline structure.
 A mineral resource is a concentration of naturally occurring material from the earth’s crust that
can be extracted and processed into useful products and raw materials at an affordable cost. Two
major types are metallic minerals (such as aluminum and gold), and nonmetallic minerals (such
as sand and limestone). Because they take so long to form, minerals are classified as
nonrenewable resources.
 Rock is a solid combination of one or more minerals found in the earth’s crust. Some kinds of
rock, such as limestone and quartzite, contain only one mineral.
 Sedimentary rock is made of sediments—dead plant and animal remains and tiny particles of
weathered and eroded rocks. Examples include sandstone, shale, dolomite, limestone, lignite and
bituminous coal.
 Igneous rock forms below or on the earth’s surface when magma wells up from the earth’s upper
mantle or deep crust and then cools and hardens. Examples include granite and lava rock.
 Metamorphic rock forms when a preexisting rock is subjected to high temperatures, high
pressures, chemically active fluids, or a combination of these agents. Examples include slate and
marble.
 The interaction of physical and chemical processes that change rocks from one type to another is
called the rock cycle. In this process, rocks are broken down, eroded, crushed, heated, melted,
fused together into new forms by heat and pressure, cooled, and/ or recrystallized within the
earth’s mantle and in the earth’s crust. The rock cycle concentrates the planet’s nonrenewable
mineral resources on which our life processes depend.
 An ore is rock that contains a large enough concentration of a particular mineral—often a metal—
to make it profitable for mining and processing. A high-grade ore contains a large concentration
of the desired mineral, whereas a low-grade ore contains a smaller concentration.
 Five important nonrenewable resources are: aluminum, steel, manganese, cobalt, and copper.
3. Section 14-2. What are the two key concepts for this section? What are the reserves of a mineral
resource and how can they be expanded? What two factors determine the future supply of a
nonrenewable mineral resource? Explain how the supply of a nonrenewable mineral resource can be
economically depleted and list the five choices we have when this occurs. What is depletion time and
what factors affect it?
Instructor's Manual: Chapter 14






Key concepts: Nonrenewable mineral resources exist in finite amounts and can become
economically depleted when it costs more than it is worth to find, extract, and process the
remaining deposits. There are several ways to extend supplies of mineral resources, but each
of them is limited by economic and environmental factors.
Reserves are identified resources from which the mineral can be extracted profitably at
current prices.
See Figure 14-11. Life cycle of a metal resource.
A supply can be economically depleted when it costs more to find than it is worth.
We can recycle or reuse existing supplies, waste less, use less, find a substitute, or do
without.
Depletion time is the time it takes to use up a certain proportion— usually 80%— of the
reserves of a mineral at a given rate of use. The shortest depletion time estimate assumes no
recycling or reuse and no increase in reserves. A longer depletion time estimate assumes that
recycling will stretch existing reserves and that better mining technology, higher prices, or
new discoveries will increase reserves. An even longer depletion time assumes that new
discoveries will further expand.
4. What five nations supply most of the world’s nonrenewable mineral resources? How dependent is the
United States on other countries for important nonrenewable mineral resources? Explain the concern
over U.S. access to rare-earth mineral resources. Describe the conventional view of the relationship
between the supply of a mineral resource and its market price. Explain why some economists believe
this relationship no longer applies. Summarize the pros and cons of providing government subsidies
and tax breaks for mining companies.
 Five nations—the United States, Canada, Russia, South Africa, and Australia—supply most of
the nonrenewable mineral resources used by modern societies.
 Currently, the United States imports all of its supplies of 20 key nonrenewable mineral resources
and more than 90% of its supplies of 4 other key minerals. The United States has little or no
reserves of manganese, cobalt, chromium, and platinum, all of which are strategic metal
resources.
 According to standard economic theory, in a competitive market system, a plentiful mineral
resource is cheap when its supply exceeds demand. When a resource becomes scarce, its price
rises. According to some economists, this price effect may no longer apply very well in most
developed countries. Industry and government in such countries often use subsidies, taxes,
regulations, and import tariffs to control the supplies, demands, and prices of minerals to such an
extent that a truly competitive market does not exist. Most mineral prices are kept artificially low
because governments subsidize development of their domestic mineral resources to help promote
economic growth and national security.
 Some economists believe that government subsidies and tax breaks have made the conventional
economic view irrelevant.
 Subsidies help mining companies discover new reserves and resources, but they also allow
environmental degradation.
5. Summarize the opportunities and limitation of expanding mineral supplies by mining lower-grade
ores. What are the advantages and disadvantages of biomining? Describe the opportunities and
possible problems that could result from deep-sea mining.
 Some analysts say we can increase supplies of a mineral by extracting lower grades of ore. They
point to the development of new earth-moving equipment, improved techniques for removing
impurities from ores, and other technological advances in mineral extraction and processing. Such
Instructor's Manual: Chapter 14


advancements have made it possible to extract some lower-grades ores and even to reduce their
costs. Several factors can limit the mining of lower-grade ores. One is the increased cost of
mining and processing larger volumes of ore. Another is the limited availability of freshwater
needed to mine and process some minerals. A third limiting factor is the environmental impacts
of the increased land disruption, waste material, and pollution produced during mining and
processing.
Using microorganisms to extract mineral, or biomining, removes desired metals from ores
through wells bored into the deposits. It leaves the surrounding environment undisturbed and
reduces the air pollution associated with the smelting of metal ores. It also reduces hazardous
chemical water pollution such as that resulting from the use of cyanide and mercury in gold
mining. However, biomining can take decades to remove the same amount of material that
conventional methods can remove within months or years. So far, biological mining methods are
economically feasible only with low-grade ores for which conventional techniques are too
expensive.
Some ocean mineral resources are dissolved in seawater. However, most of the chemical
elements found in seawater occur in such low concentrations that recovering these mineral
resources takes more energy and money than they are worth. Currently, only magnesium,
bromine, and sodium chloride are abundant enough to be extracted profitably.
6. Section 14-3. What is the key concept for this section? Summarize the life cycle of a metal product.
 Key concept: Extracting minerals from the earth’s crust and converting them into useful products
can disturb the land, erode soils, produce large amounts of solid waste, and pollute the air, water,
and soil.
 The life cycle of a metal product includes mining, processing, manufacturing a product, disposal,
and recycling.
7. What is surface mining? Define overburden and spoils. Define open-pit mining and strip mining and
distinguish among area strip mining, contour strip mining, and mountaintop removal mining.
Describe three harmful environmental effects of surface mining. What is subsurface mining? Describe
the harmful effects of gold mining. Describe the environmental effects of mining and processing rareearths. Define tailings and explain why they can be hazardous. What is smelting and what are its
major harmful environmental effects?
 Shallow mineral deposits are removed by surface mining, in which materials lying over a deposit
are removed to expose the resource for processing.
 Overburden is the soil and rock overlying a useful mineral deposit. Overburden is usually set
aside in piles of waste material, called spoils.
 In open-pit mining, machines dig very large holes and remove ores, sand, gravel, and stone such
as limestone and marble.
 Strip mining is useful and economical for extracting mineral deposits that lie in large horizontal
beds close to the earth’s surface. There are several types of strip mining.
o In area strip mining, used where the terrain is fairly flat, a gigantic earthmover strips
away the overburden, and a power shovel removes the mineral deposit.
o Contour strip mining is used mostly to mine coal on hilly or mountainous terrain. A huge
power shovel cuts a series of terraces into the side of a hill. Colossal earthmovers remove
the overburden, a power shovel extracts the coal, and the overburden from each new
terrace is dumped onto the one below.
o Another surface mining method is mountaintop removal. In the Appalachian Mountains
of the United States, where this form of mining is prominent, explosives, large power
Instructor's Manual: Chapter 14





shovels, and huge machines, called draglines, are used to remove the top of a mountain
and expose seams of coal, which are then removed.
Deep deposits of minerals are removed by subsurface mining, in which mineral resources are
removed from underground through tunnels and shafts.
See Figure 14-12: Some harmful environmental effects of extracting, processing, and using
nonrenewable mineral and energy resources.
Gold is mined with cyanide and cyanide salts, which are highly toxic to organisms.
Tailings are waste piles from mining. They can contain toxic heavy metals.
Heating ores to release metals is called smelting. Without effective pollution control equipment,
smelters emit enormous quantities of air pollutants, including sulfur dioxide and suspended
particles, which damage vegetation and acidify soils in the surrounding area. Smelters also cause
water pollution and produce liquid and solid hazardous wastes that require safe disposal.
8. Section 14-4. What is the key concept for this section? Describe the opportunities and limitations of
finding substitutes for key mineral resources. What is nanotechnology and what are some of its
potential environmental and other benefits? What are some problems that could arise from the
widespread use of nanotechnology? Describe the potential of using graphene as a new resource.
Explain the benefits of recycling and reusing valuable minerals. List five ways to use nonrenewable
mineral resources more sustainably. What are two examples of research into substitutes for rare-earth
metals? What is the relationship between lithium and U.S. energy independence?
 Key concept: We can try to find substitutes for scarce resources, reduce resource waste, and
recycle and reuse minerals.
 Some analysts believe that human ingenuity will find substitutes for key minerals. They point to
nanotechnology and to the current materials revolution in which silicon and new materials,
particularly ceramics and plastics, are being used as replacements for metals. Plastic has replaced
copper, steel, and lead in much piping. Fiber-optic glass cables that transmit pulses of light are
replacing copper and aluminum wires in telephone cables. However, use of plastics has
drawbacks, chief of which is that making them by current methods requires the use of oil and
other fossil fuels. Substitution is not a cure- all. For example, currently, platinum is unrivaled as
an industrial catalyst, and chromium is an essential ingredient of stainless steel. We can try to find
substitutes for scarce resources but this may not always be possible.
 Scientists plan to use atoms of abundant substances such as carbon, silicon, silver, titanium, and
boron as building blocks to create an immense array of products, effectively diminishing the
importance of the mining industry.
 Nanotechnology is potentially problematic because as particles get smaller they become more
reactive and potentially more toxic to humans and other animals.
 Graphene could revolutionize the electric car industry by leading to the production of new and
better batteries, and it could replace silicon in computer chips and other electronic devices.
 The benefits of recycling and reuse include less energy use, less air pollution, and less water
pollution.
 Ways to achieve more sustainable use of nonrenewable mineral resources:
o Do not waste mineral resources.
o Recycle and reuse 60–80% of mineral resources.
o Include the harmful environmental costs of mining and processing minerals in the prices of
items (full-cost pricing).
o Reduce mining subsidies.
o Increase subsidies for recycling, reuse, and finding substitutes.
o Redesign manufacturing processes to use less mineral resources and to produce less pollution
and waste (cleaner production).
Instructor's Manual: Chapter 14
o


Use mineral resource wastes of one manufacturing process as raw materials for other
processes.
o Slow population growth.
Electric motors for hybrid-electric vehicles and electromagnets for wind turbines are being made
that use no rare-earth metals.
Lithium is not produced in the United States, yet it is needed for lithium-ion batteries. We are
dependent on other countries for our lithium.
9. Section 14-5. What is the key concept for this section? What are tectonic plates, and what typically
happens when they collide, move apart, or grind against one another? Define volcano and describe the
nature and major effects of a volcanic eruption. Define earthquake and describe its nature and major
effects. What is a tsunami and what are its major effects?
 Key concept: Dynamic processes move matter within the earth and on its surface and can cause
volcanic eruptions, earthquakes, tsunamis, erosion, and landslides.
 Tectonic plates are huge rigid plates that move extremely slowly atop the denser mantle. They
were likely formed from the flows of energy and heated material in convection cells that caused
the lithosphere to break up.
 Tectonic plates can also slide and grind past one another along a fracture (fault) in the
lithosphere—a type of boundary called a transform fault. It consists of the continental crust,
which underlies the continents (including the continental shelves extending into the oceans), and
the oceanic crust, which underlies the ocean basins and makes up 71% of the earth’s crust.
Subduction is when an oceanic plate collides with a continental plate. The continental plate
usually rides up over the denser oceanic plate and pushes it down into the mantle. The area where
this collision and subduction takes place is called a subduction zone.
 Weathering is the physical, chemical, and biological processes that break down rocks into smaller
particles that help build soil. Weathering plays a key role in soil formation.
 A volcano is created when magma in the partially molten asthenosphere rises in a plume through
the lithosphere to erupt on the surface as lava, which builds a cone. Sometimes, internal pressure
is high enough to cause lava, ash, and gases to be ejected into the atmosphere or to flow over
land, causing considerable damage.
 Forces inside the earth’s mantle and near its surface push, deform, and stress rocks. The stress
can cause the rocks to suddenly shift or break and produce a transform fault, or fracture, in the
earth’s crust. When a fault forms, or when there is abrupt movement on an existing fault, energy
that has accumulated over time is released in the form of vibrations, called seismic waves, which
move in all directions through the surrounding rock. This internal geological process is called an
earthquake. Most earthquakes occur at the boundaries of tectonic plates when colliding plates
create tremendous pressures in the earth’s crust or when plates slide past one another at transform
faults. Relief of the earth’s internal stress releases energy as shock (seismic) waves, which move
outward from the earthquake’s focus like ripples in a pool of water. Scientists measure the
severity of an earthquake by the magnitude of its seismic waves.
 A tsunami is a series of large waves generated when part of the ocean floor suddenly rises or
drops. Most large tsunamis are caused when certain types of faults in the ocean floor move up or
down as a result of a large underwater earthquake, a landslide caused by such an earthquake, or in
some cases by a volcanic eruption. Tsunamis are often called tidal waves, although they have
nothing to do with tides. They can travel far across the ocean at the speed of a jet plane. In deep
water the waves are very far apart and their crests are not very high. As a tsunami approaches a
coast, it slows down, its wave crests squeeze closer together, and their heights grow rapidly. It
can hit a coast as a series of towering walls of water that can level buildings.
Instructor's Manual: Chapter 14
10. What are the three big ideas of this chapter? Explain how we can apply the three principles of
sustainability in order to obtain and use rare-earth metals and other nonrenewable mineral resources
in more sustainable ways.
 The three big ideas:
o Dynamic forces that move matter within the earth and on its surface recycle the earth’s rocks,
form deposits of mineral resources, and cause volcanic eruptions, earthquakes, and tsunamis.
o The available supply of a mineral resource depends on how much of it is in the earth’s crust,
how fast we use it, mining technology, market prices, and the harmful environmental effects
of removing and using it.
o We can use mineral resources more sustainably by trying to find substitutes for scarce
resources, reducing resource waste, and reusing and recycling nonrenewable minerals.
 Mineral resources should not be extracted more rapidly natural cycles can replenish them, they
should not be extracted in a way that compromises the health or survival of humans or other
species, and the energy used in making materials should be minimized or provided solely by the
sun. Mineral resources should be recycled and reused as much as possible.
p
Instructor's Manual: Chapter 14