Outline Miller Chapter 14 Review

Chapter 14: Nonrenewable Mineral Resources
14-1: What Are the Earth’s Major Geological Processes and What Are Mineral Resources?
Geology – the science devoted to the study of dynamic processes taking place on the Earth’s surface and in its interior
Three major concentric zones:
Core – the earth’s innermost zone
Mantle – a zone made mostly of solid rock that can be soft and pliable
Asthenosphere – a volume of hot, partly melted rock that flows
Convection Cells (currents) – that slowly move large volumes of rock and heat in loops within the mantle like gigantic conveyor belts
The combination of the crust and the rigid, outermost part of the mantle is called
We find the mineral resources on which we depend
Crust – the outermost and thinnest zone of solid material
Continental Crust – which underlies the continents (including the continental shelves extending into the oceans)
Oceanic Crust – underlies the ocean basins
Mineral – a naturally occurring chemical element or inorganic compound that exists as a solid with a regularly repeating internal arrangement of its atoms or ions (a crystalline solid)
Mineral Resource – a concentration of one or more minerals in the earth’s crust that we can extract and process into raw materials and useful products at an affordable cost
Are classified as nonrenewable resources, and their supplies can be depleted
Metallic Minerals – made of single elements, such as Aluminum, Gold, and the rare earths (used for technology), and those made of compounds such as rare earth oxides
Nonmetallic Minerals – sand and limestone – made of nonmetallic elements and compounds
Rock – a solid combination of one or more minerals found in the earth’s crust
Sedimentary Rock – made of sediments – dead plant and animal remains and tiny particles of weathered and eroded rock – deposited in layers that accumulate over time
Igneous Rock – forms below or on the earth’s surface under intense heat and pressure when magma wells up from the earth’s mantle and then cools and hardens
Igneous rock forms the bulk of the earth’s crust but is usually covered by sedimentary rock
Metamorphic Rock – forms when an existing rock is subjected to high temperatures, high pressure, chemically active fluids, or a combination of these agents
Rock Cycle – the interaction of physical and chemical processes that change the earth’s rocks from one type to another --- this is the slowest of the earth’s cyclic processes
Three processes:
Erosion
Melting
Metamorphism
High-Grade Ore – contains a large concentration of the desired mineral
Low-Grade Ore – contains smaller concentrations of the desired mineral
Phosphates Salts – used to make inorganic fertilizer and certain detergents
14-2: How Long Might Supplies of Nonrenewable Mineral Resources Last?
Reserves – supply, identified deposits from which we can extract the mineral profitably at current prices
The future supply of any nonrenewable mineral resources depends on the actual or potential supply of the mineral and the rate at which we use it
Mineral becomes economically depleted when it costs more than it is worth to find, extract, transport, and process the remaining deposits
Recycle or reuses existing supplies
Waste less – use less
Find a substitute
Do without
The US, Canada, Russia, South Africa, and Australia – supply most of the nonrenewable mineral resources used by modern societies
Depletion Time – 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 (Curve A)
Longer depletion-time estimate assumes that recycling will stretch existing reserves and that better mining technology, higher prices, or new discovers will increase reserves (Curve B)
Longest depletion-time estimate makes the same assumptions and A and B, but also includes reused and reduced consumption to further expand reserves (Curve C)

Most US imports of metallic mineral resources come from reliable and politically stable countries --- HOWEVER --- there are serious concerns about access to adequate supplies of four major metal resources – manganese, cobalt, chromium, and platinum
The US has little to no reserves of these metals
Rare-earth elements are not actually rare, for the most part, but they are hard to find in concentrations high enough to extract and process at an affordable price
China produces about 97% of the world’s rare-earth metals and oxides --- partly because China does not strictly regulate the environmentally disruptive mining and processing of rare earth (lower cost to consumer as well)
A large rare-earth mine in California – the only one in the US – used to be the world’s largest supplier of rare-earth metals ---HOWEVER --- it closed down because of the expense of meeting pollution regulations, and because China had driven the prices of rare-earth metals down to a point where the mine was too costly to operate
China’s growing use of these resources means that it will use most of the rare earths it produces and may soon need to important some types of rare earths from other countries to meet its industrial needs
The transition from developing to developed
Geological processes determine the quantity and location of a nonrenewable mineral resource in the earth’s crust, but economics determines what part of the known supply is extracted and used
Standard Economic theory – in a competitive market system when a resource becomes scarce, its price rises (can encourage growth)
Stimulate development of better mining technology and make it profitable to min lower-grade ores
This price effect may no longer apply very well in most of the more-developed countries
Governments in such countries often use subsidies, tax breaks, and import tariffs to control the supply, demand, and prices of key mineral resources to such an extent that a truly competitive free market does not exist
US – mining, companies get various types of government subsidies, including depletion allowances
Mining company representatives insist low taxes to keep the prices of minerals low for consumers without the subsidies - their companies might move their operations to other countries – would not have to deal with strict mining and pollution control regulations (aka: outsourcing jobs)
Increase supplies of some minerals by extracting them from lower-grade ores
Development of new earth-moving equipment, improved techniques for removing impurities from ores, and other technological advances in mineral extraction and processing that can make lower-grade ores accessible
Several factors can limit the mining of lower grade ores
Requires mining and processing larger volumes of ore – which takes more energy and cost more
Dwindling supplies of freshwater needed for the mining and processing of some minerals
The growing environmental impacts of land disruption
Waste material and pollution produced during mining and processing
The growing environmental impacts of land disruption, along with waste material and pollution produced during mining and processing
Biomining - biological approach – miners use natural or genetically engineered bacteria to remove desired metals from ores through wells bored into the deposits
Is slow and can take decades
Feasible only with low-grade ores for which conventional techniques are too expensive
Because of the rapidly rising prices of many of these metals, there is growing interest in deep-sea mining
The UN International Seabed Authority – established to manage seafloor mining in international waters, began issuing mining permits in 2011
Marine biologist are concerned that the sediment stirred up by such mining could harm or kill organism
Proponents of mining say that the number of potential mining sites is quite small and that many of these organisms can live elsewhere
Obtaining minerals from the ocean bottom has been hindered by high costs involved, the potential threat to marine ecosystems, and arguments over rights to these minerals in deep-ocean areas that belong to no one country

14-3: What Are the Environmental Effects of Using Nonrenewable Mineral Resources?
Life Cycle – that includes mining the mineral, processing it, manufacturing the product, and disposal or recycling of the product
Large amounts of energy and water, and results in pollution and waste
Environmental impacts of mining a metal ore are determined by the ore’s percentage of metal content, or grade
Surface Mining – overlying a mineral deposit are cleared away
Overburden – usually deposited in piles of waste material (aka: spoils)
Types of surface mining used depends on two factors:
The resource being sought
Local topography
Open-pit mining – very large holes
Strip mining – large horizontal beds close to the earth’s surface
Area strip mining – the terrain is fairly flat
Contour strip mining – on hilly or mountainous terrain
Unless the land is restored, what is left are a series of spoils banks and highly erodible bank of soil and rock (highwall)
Mountaintop removal – this destroys forests, buries mountain streams, and increases the risk of flooding – wastewater and toxic sludge, produced when the coal is processed are often stored behind dams in these valleys – which can overflow or collapse and release toxic substances such as arsenic and mercury
Commonly used in the Appalachian Mountains of the US
Sites can be cleaned up and restored but it is costly and is rarely done even when required by law
Subsurface Mining – disturbs less than one-tenth as much land as surface mining, and it usually produces less waste material
Creates hazards such as cave-ins, explosions, and fires
Subsidence – the collapse of land above some underground mines
Surface and subsurface mining operations also produce large amounts of solid waste and cause major water and air pollution
Acid mine drainage – carries sulfuric acid (H2SO4)
Ore extracted has two components:
Ore Mineral
Waste Material
Produces tailings that are left in piles or put into tailings ponds where they settle out
Tailing ponds can also leak and contaminate surface water and groundwater
Smelting – heating ores to release metals – emit sulfur dioxide and suspended toxic particles, which damage vegetation and acidify soils in the surrounding area
Cause water pollution and produce liquid and solid hazardous wastes that require safe disposal
Lead smelting is the world’s second most toxic industry after the recycling of lead-acid batteries
14-4: How Can We Use Mineral Resources More Sustainably?
Materials Revolution – which silicon and other materials are replacing some metals for common use
Resource substitution is not a cure-all
Several ways to use mineral resources more sustainably – focus on recycling and reuse of nonrenewable mineral resources
Recycling has a much lower environmental impact than that of mining and processing metals from ores
Example: cleaning up and reusing items instead of recycling them has an even lower environmental impact
14-5: What Are the Earth’s Major Geological Hazards?
Tectonic Plates – which move extremely slowly atop the asthenosphere
Much of the geological activity at the earth’s surface takes place at the boundaries between tectonic plates as they separate, collide, or grind along against each other
Volcano – occurs where magma rising in a plume through the lithosphere reaches the earth’s surface through a central vent or a long crack (fissure)
Magma that reaches earth’s surface is called lava
Volcanoes form when one plate slides under or moves away from another plate
Do provide some benefits in the formation of majestic mountains and lakes such as Crater Lake – contribute to fertile soil – forms islands that have become favorable for human settlement
Earthquake – energy that has accumulated over time is released in the forms of vibrations (seismic waves) that move in all directions through the surrounding rock
Fault – a fracture in earth’s crust
Seismic waves move upward and outward from the earthquake’s focus
Measure the severity of an earthquake by the magnitude of its seismic waves
Measure of ground motion (shaking) caused by the earthquake – indicated by amplitude – Richter Scale
Primary Effects of the seismic waves – include shaking and sometimes a permanent vertical or horizontal displacement of a part of the crust
Tsunami – a series of large waves generated when part of the ocean floor suddenly rises or drops
Most faults in the ocean floor move up or down
As a tsunami approaches a coast with its shallow waters, it slows down, its wave crests squeeze closer together, and their heights grow rapidly