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Chapter 15Chapter 15
Nonrenewable Mineral Nonrenewable Mineral ResourcesResources
MINERALS, ROCKS, AND THE MINERALS, ROCKS, AND THE ROCK CYCLEROCK CYCLE
The earth’s crust consists of solid inorganic The earth’s crust consists of solid inorganic elements and compounds called minerals elements and compounds called minerals that can sometimes be used as resources.that can sometimes be used as resources. Mineral resourceMineral resource: is a concentration of : is a concentration of
naturally occurring material in or on the earth’s naturally occurring material in or on the earth’s crust that can be extracted and processed into crust that can be extracted and processed into useful materials at an affordable cost.useful materials at an affordable cost.
General Classification of General Classification of Nonrenewable Mineral ResourcesNonrenewable Mineral Resources
The U.S. Geological Survey classifies The U.S. Geological Survey classifies mineral resources into four major categories:mineral resources into four major categories: IdentifiedIdentified: known location, quantity, and quality : known location, quantity, and quality
or existence known based on direct evidence and or existence known based on direct evidence and measurements.measurements.
UndiscoveredUndiscovered: potential supplies that are : potential supplies that are assumed to exist.assumed to exist.
ReservesReserves: identified resources that can be : identified resources that can be extracted profitably.extracted profitably.
Other: undiscovered or identified resources not Other: undiscovered or identified resources not classified as reservesclassified as reserves
General Classification of General Classification of Nonrenewable Mineral ResourcesNonrenewable Mineral Resources
Examples are Examples are fossil fuels (coal, fossil fuels (coal, oil), metallic oil), metallic minerals (copper, minerals (copper, iron), and iron), and nonmetallic nonmetallic minerals (sand, minerals (sand, gravel).gravel).
Figure 15-7Figure 15-7
GEOLOGIC PROCESSESGEOLOGIC PROCESSES
Deposits of nonrenewable mineral resources Deposits of nonrenewable mineral resources in the earth’s crust vary in their abundance in the earth’s crust vary in their abundance and distribution.and distribution.
A very slow chemical cycle recycles three A very slow chemical cycle recycles three types of rock found in the earth’s crust:types of rock found in the earth’s crust: Sedimentary rock (sandstone, limestone).Sedimentary rock (sandstone, limestone). Metamorphic rock (slate, marble, quartzite).Metamorphic rock (slate, marble, quartzite). Igneous rock (granite, pumice, basalt).Igneous rock (granite, pumice, basalt).
Rock CycleRock Cycle
Figure 15-8Figure 15-8
ENVIRONMENTAL EFFECTS OF ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCESUSING MINERAL RESOURCES
The extraction, processing, and use of The extraction, processing, and use of mineral resources has a large environmental mineral resources has a large environmental impact.impact.
Figure 15-9Figure 15-9
Fig. 15-9, p. 344
Surface mining
Metal ore Separation of ore from gangue
Smelting Melting metal
Conversion to product
Discarding of product (scattered in environment)
Recycling
Fig. 15-10, p. 344
Natural Capital Degradation
Extracting, Processing, and Using Nonrenewable Mineral and Energy Resources
StepsSteps Environmental effectsEnvironmental effects
Mining Disturbed land; mining accidents; health hazards, mine waste dumping, oil spills and blowouts; noise; ugliness; heat
Exploration, extraction
Processing
Solid wastes; radioactive material; air, water, and soil pollution; noise; safety and health hazards; ugliness; heat
Transportation, purification, manufacturing
Use
Noise; ugliness; thermal water pollution; pollution of air, water, and soil; solid and radioactive wastes; safety and health hazards; heat
Transportation or transmission to individual user, eventual use, and discarding
ENVIRONMENTAL EFFECTS OF ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCESUSING MINERAL RESOURCES
Minerals are removed through a variety of Minerals are removed through a variety of methods that vary widely in their costs, safety methods that vary widely in their costs, safety factors, and levels of environmental harm.factors, and levels of environmental harm.
A variety of methods are used based on A variety of methods are used based on mineral depth.mineral depth. Surface miningSurface mining: shallow deposits are removed.: shallow deposits are removed. Subsurface miningSubsurface mining: deep deposits are removed.: deep deposits are removed.
Open-pit MiningOpen-pit Mining
Machines dig Machines dig holes and holes and remove ores, remove ores, sand, gravel, sand, gravel, and stone.and stone.
Toxic Toxic groundwater can groundwater can accumulate at accumulate at the bottom.the bottom.
Figure 15-11Figure 15-11
Area Strip MiningArea Strip Mining
Earth movers Earth movers strips away strips away overburden, and overburden, and giant shovels giant shovels removes mineral removes mineral deposit.deposit.
Often leaves highly Often leaves highly erodible hills of erodible hills of rubble called rubble called spoil spoil banksbanks..
Figure 15-12Figure 15-12
Contour Strip MiningContour Strip Mining
Used on hilly or Used on hilly or mountainous mountainous terrain.terrain.
Unless the land is Unless the land is restored, a wall of restored, a wall of dirt is left in front dirt is left in front of a highly of a highly erodible bank erodible bank called a called a highwallhighwall..
Figure 15-13Figure 15-13
Mountaintop RemovalMountaintop Removal
Machinery Machinery removes the tops removes the tops of mountains to of mountains to expose coal.expose coal.
The resulting The resulting waste rock and dirt waste rock and dirt are dumped into are dumped into the streams and the streams and valleys below.valleys below.
Figure 15-14Figure 15-14
Mining ImpactsMining Impacts
Metal ores are Metal ores are smelted or treated smelted or treated with (potentially toxic) with (potentially toxic) chemicals to extract chemicals to extract the desired metal.the desired metal.
Figure 15-15Figure 15-15
SUPPLIES OF MINERAL SUPPLIES OF MINERAL RESOURCESRESOURCES
The future supply of a resource depends on The future supply of a resource depends on its affordable supply and how rapidly that its affordable supply and how rapidly that supply is used.supply is used.
A rising price for a scarce mineral resource A rising price for a scarce mineral resource can increase supplies and encourage more can increase supplies and encourage more efficient use.efficient use.
SUPPLIES OF MINERAL SUPPLIES OF MINERAL RESOURCESRESOURCES
Depletion curves Depletion curves for a renewable for a renewable resource using resource using three sets of three sets of assumptions. assumptions. Dashed vertical Dashed vertical
lines represent lines represent times when 80% times when 80% depletion occurs.depletion occurs.
Figure 15-16Figure 15-16
SUPPLIES OF MINERAL SUPPLIES OF MINERAL RESOURCESRESOURCES
New technologies can increase the mining of New technologies can increase the mining of low-grade ores at affordable prices, but low-grade ores at affordable prices, but harmful environmental effects can limit this harmful environmental effects can limit this approach.approach.
Most minerals in seawater and on the deep Most minerals in seawater and on the deep ocean floor cost too much to extract, and ocean floor cost too much to extract, and there are squabbles over who owns them.there are squabbles over who owns them.
USING MINERAL RESOURCES USING MINERAL RESOURCES MORE SUSTAINABLYMORE SUSTAINABLY
Scientists and engineers are developing new Scientists and engineers are developing new types of materials as substitutes for many types of materials as substitutes for many metals.metals.
Recycling valuable and scarce metals saves Recycling valuable and scarce metals saves money and has a lower environmental impact money and has a lower environmental impact then mining and extracting them from their then mining and extracting them from their ores.ores.
Fig. 15-18, p. 351
Solutions
Sustainable Use of Nonrenewable Minerals
• Do not waste mineral resources.
• Recycle and reuse 60–80% of mineral resources.
• Include the harmful environmental costs of mining and processing minerals in the prices of items (full-cost pricing).
• Reduce subsidies for mining mineral resources.
• Increase subsidies for recycling, reuse, and finding less environmentally harmful substitutes.
• Redesign manufacturing processes to use less mineral resources and to produce less pollution and waste.
• Have the mineral-based wastes of one manufacturing process become the raw materials for other processes.
• Sell services instead of things.
• Slow population growth.
Case Study: Case Study: The Ecoindustrial RevolutionThe Ecoindustrial Revolution
Growing signs point to an ecoindustrial Growing signs point to an ecoindustrial revolution taking place over the next 50 revolution taking place over the next 50 years.years.
The goal is to redesign industrial The goal is to redesign industrial manufacturing processes to mimic how manufacturing processes to mimic how nature deals with wastes.nature deals with wastes. Industries can interact in complex resource Industries can interact in complex resource
exchange webs in which wastes from exchange webs in which wastes from manufacturer become raw materials for another.manufacturer become raw materials for another.
Fig. 15-19, p. 352
Sludge
Pharmaceutical plant Local farmers
SludgeGreenhouses W
aste heat
Waste heat
Waste heat
Waste heat Fish farming
Oil refinery Surplus natural gas
Electric power plant
Fly ash
Surplus sulfur
Surplus natural gas
Waste calcium sulfate
Waste heat
Cement manufacturer
Sulfuric acid producer
Wallboard factory Area homes