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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.
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.
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