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