Chapter 16Chapter 16Minerals: A Non-renewable ResourceMinerals: A Non-renewable Resource

Overview of Chapter 16Overview of Chapter 16

Introduction to MineralsIntroduction to Minerals• Mineral Distribution and FormationMineral Distribution and Formation• How Minerals are Found and ExtractedHow Minerals are Found and Extracted

Environmental Impact of MineralsEnvironmental Impact of MineralsAn International PerspectiveAn International PerspectiveIncreasing the Supply of MineralsIncreasing the Supply of MineralsSubstitution and ConservationSubstitution and Conservation

Introduction to MineralsIntroduction to MineralsMineralsMinerals

• Elements or compounds of elements that Elements or compounds of elements that occur naturally in Earth’s crustoccur naturally in Earth’s crust

RocksRocks• Naturally formed aggregates of mineralsNaturally formed aggregates of minerals

Examples of MineralsExamples of Minerals• Concrete (mixture of Concrete (mixture of sand, gravel and sand, gravel and limestone)limestone)

Introduction to MineralsIntroduction to MineralsExamples of MineralsExamples of Minerals

• Table salt (nonmetal)Table salt (nonmetal)• Copper (metal)Copper (metal)

Mineral Distribution and Mineral Distribution and FormationFormation

Abundant minerals in crustAbundant minerals in crust• Aluminum and ironAluminum and iron

Scarce minerals in crustScarce minerals in crust• Copper, chromium, and molybdenumCopper, chromium, and molybdenum

Distributed unevenly across globeDistributed unevenly across globe• If found in low abundance, mining is not If found in low abundance, mining is not

profitableprofitable

Formation of Mineral DepositsFormation of Mineral DepositsResult of natural processesResult of natural processes

• Magmatic concentrationMagmatic concentration• As magma cools heavier elements (Fe and Mg) As magma cools heavier elements (Fe and Mg)

settlesettle• Responsible for deposits of Fe, Cu, Ni, CrResponsible for deposits of Fe, Cu, Ni, Cr

• Hydrothermal processesHydrothermal processes• Minerals are carried and deposited by water Minerals are carried and deposited by water

heated deep in earth’s crust: Au, Ag, Cu, Pb, Znheated deep in earth’s crust: Au, Ag, Cu, Pb, Zn• SedimentationSedimentation

• Weathered particles are transported by water and Weathered particles are transported by water and deposited as sediment on sea floor or shore: Fe, deposited as sediment on sea floor or shore: Fe, Mg, S, Cu, PMg, S, Cu, P

• EvaporationEvaporation• Salts are left behind after water body dries up: K, Salts are left behind after water body dries up: K,

NaCl, Borax, salts, gypsumNaCl, Borax, salts, gypsum

Discovering Mineral DepositsDiscovering Mineral DepositsScientists (geologists) use a variety of Scientists (geologists) use a variety of

instruments and measurementsinstruments and measurements• Aerial or satellite photographyAerial or satellite photography• Aircraft and satellite instruments that Aircraft and satellite instruments that

measure Earth’s magnetic fieldmeasure Earth’s magnetic field• SeismographsSeismographs

Combine this with knowledge of how Combine this with knowledge of how minerals are formedminerals are formed

Extracting MineralsExtracting MineralsSurface MiningSurface Mining

• Mineral and energy resources are extracted Mineral and energy resources are extracted near Earth’s surface by removing soil, near Earth’s surface by removing soil, subsoil and over-lying rock stratasubsoil and over-lying rock strata

• More common because less expensiveMore common because less expensive• Two kinds: open pit and strip miningTwo kinds: open pit and strip mining

Subsurface MiningSubsurface Mining• Mineral and energy resources are extracted Mineral and energy resources are extracted

from deep underground depositsfrom deep underground deposits• Two kinds: shaft mine and slope mineTwo kinds: shaft mine and slope mine

Extracting Minerals-Extracting Minerals-Open Pit Surface MiningOpen Pit Surface Mining

Processing MineralsProcessing MineralsSmelting- Smelting-

process in process in which ore is which ore is melted at high melted at high temps to temps to separate separate impurities from impurities from the molten the molten metalmetal

Environmental Impacts of Environmental Impacts of MineralsMinerals

Disturbs large areaDisturbs large area• Prone to erosionProne to erosion

Uses large quantities of waterUses large quantities of water• Must pump water out of mine to keep it dryMust pump water out of mine to keep it dry

Acid Mine Drainage (AMD)Acid Mine Drainage (AMD)• Pollution caused when sulfuric acid and Pollution caused when sulfuric acid and

dissolved lead, arsenic or cadmium wash dissolved lead, arsenic or cadmium wash out of mines into nearby waterwaysout of mines into nearby waterways

Environmental Impacts of Refining Environmental Impacts of Refining MineralsMinerals

Environmental Impacts of Refining Environmental Impacts of Refining MineralsMinerals

80% or more of mined 80% or more of mined ore consists of ore consists of impurities- called impurities- called tailingstailings• Contain toxic materialsContain toxic materials

Smelting plants emit Smelting plants emit large amounts of air large amounts of air pollutantspollutants

Requires a lot of energy Requires a lot of energy (fossil fuels (fossil fuels combustion)combustion)

Case-In-Point Copper Basin, TNCase-In-Point Copper Basin, TN

Restoration of Mining LandsRestoration of Mining LandsGoals: prevent further degradation and Goals: prevent further degradation and

erosion of land, eliminate local sources erosion of land, eliminate local sources of toxins and make land productive for of toxins and make land productive for another purpose (SMCAR)another purpose (SMCAR)

Restoration of Mining LandRestoration of Mining LandCreative ApproachesCreative Approaches- Wetlands- Wetlands

• Trap sediment and pollutants before they Trap sediment and pollutants before they get into streams, improving water qualityget into streams, improving water quality

• Expensive to create and maintain, but cost Expensive to create and maintain, but cost effective compared to using lime to effective compared to using lime to decrease aciditydecrease acidity

- Phytoremediation- Phytoremediation• Use of specific plants to absorb and Use of specific plants to absorb and

accumulate toxic materials in soilaccumulate toxic materials in soil• Great potentialGreat potential

Minerals: An International Minerals: An International PerspectivePerspective

Highly developed countries rely on Highly developed countries rely on mineral deposits in developing mineral deposits in developing countriescountries• They have exhausted their own suppliesThey have exhausted their own supplies

Governments in developing countries Governments in developing countries lack financial resources to handle lack financial resources to handle pollutionpollution• Acid mine drainageAcid mine drainage• Air and water pollutionAir and water pollution

North American Consumption of North American Consumption of Selected MetalsSelected Metals

Will We Run Out of Important Will We Run Out of Important Metals?Metals?

Mineral ReservesMineral Reserves• Mineral deposits that have been identified Mineral deposits that have been identified

and are currently profitable to extractand are currently profitable to extract

Increasing Supply of Minerals –Increasing Supply of Minerals –Locating and Mining New DepositsLocating and Mining New Deposits

Many known mineral deposits have not Many known mineral deposits have not yet been exploitedyet been exploited• Difficult to accessDifficult to access

• Ex: Malaria ridden forests of IndonesiaEx: Malaria ridden forests of Indonesia• Insufficient technologyInsufficient technology

• Ex: polar regionsEx: polar regions• Located too deepLocated too deep

• Ex: 10km or deeperEx: 10km or deeper

Increasing Supply of Minerals –Increasing Supply of Minerals –Minerals in AntarcticaMinerals in Antarctica

No substantial mineral deposits identified No substantial mineral deposits identified to dateto date• Geologists feel they will be discovered in Geologists feel they will be discovered in

near futurenear future• No one owns AntarcticaNo one owns Antarctica

Antarctica Treaty (1961)Antarctica Treaty (1961)• Limits activity to peaceful uses (i.e. Limits activity to peaceful uses (i.e.

scientific studies)scientific studies)Madrid Protocol (1990)Madrid Protocol (1990)

• Moratorium on mineral exploration and Moratorium on mineral exploration and development for minimum of 50 yearsdevelopment for minimum of 50 years

Increasing Supply of Minerals- Increasing Supply of Minerals- Minerals from the OceanMinerals from the Ocean

May provide us with future suppliesMay provide us with future supplies• Extracting minerals from seawaterExtracting minerals from seawater• Mining seafloor- Manganese nodules Mining seafloor- Manganese nodules

(below)(below)

Advance Mining and Processing Advance Mining and Processing TechnologiesTechnologies

Special techniques to make use of large, Special techniques to make use of large, low-grade mineral deposits world-widelow-grade mineral deposits world-wide• Currently requires a lot of energyCurrently requires a lot of energy

BiominingBiomining• Using microorganisms to extract minerals Using microorganisms to extract minerals

from low-grade oresfrom low-grade ores

Finding Mineral SubstitutesFinding Mineral SubstitutesImportant goal in manufacturingImportant goal in manufacturing

• Driven by economics- cut costs!Driven by economics- cut costs!Substitute expensive/scarce mineral Substitute expensive/scarce mineral

resources for inexpensive/abundant onesresources for inexpensive/abundant onesExamples: Examples:

• Using plastic, glass or aluminum in place of tinUsing plastic, glass or aluminum in place of tin• Using plastic instead of lead and steel in Using plastic instead of lead and steel in

telecommunications cablestelecommunications cables• Using glass fibers instead of copper wiring in Using glass fibers instead of copper wiring in

telephone cablestelephone cables

Mineral ConservationMineral ConservationIncludes reuse and recycling of existing Includes reuse and recycling of existing

mineral suppliesmineral supplies• Reuse- using items over and over againReuse- using items over and over again

• Reduces both mineral consumption and pollutionReduces both mineral consumption and pollution• Benefits greater than recyclingBenefits greater than recycling

• Recycling- converting item into new productRecycling- converting item into new product• Common practice throughout industrialized worldCommon practice throughout industrialized world• Reduces land destruction from miningReduces land destruction from mining• Reduces solid wasteReduces solid waste• Decreases energy consumption and pollutionDecreases energy consumption and pollution

Changing Our Mineral Changing Our Mineral RequirementsRequirements

Must change out “throw away” mentalityMust change out “throw away” mentality• Damaged or unneeded articles are thrown Damaged or unneeded articles are thrown

awayaway

Mineral Flow in an Industrial SocietyMineral Flow in an Industrial Society