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17 TH MILLER/SPOOLMAN LIVING IN THE ENVIRONMENT Chapter 14 Geology and Nonrenewable Mineral Resources Slide 2 Core Case Study: The Real Cost of Gold Gold producers China South Africa Australia United States Canada Cyanide heap leaching Extremely toxic to birds and mammals Spills contaminate drinking water and kill birds and fish Slide 3 Gold Mine with Cyanide Leach Piles and Ponds in South Dakota, U.S. Fig. 14-1, p. 346 Slide 4 14-1 What Are the Earths Major Geological Processes and Hazards? Concept 14-1 Dynamic processes move matter within the earth and on its surface, and can cause volcanic eruptions, earthquakes, tsunamis, erosion, and landslides. Slide 5 The Earth Is a Dynamic Planet What is geology? Dynamic processes taking place on earths surface and in earths interior Three major concentric zones of the earth Core Mantle Including the asthenosphere Crust Continental crust Oceanic crust: 71% of crust Slide 6 Major Features of the Earths Crust and Upper Mantle Fig. 14-2, p. 348 Slide 7 Volcanoes Folded mountain belt Abyssal fl oor Oceanic ridge Abyssal fl oor Trench Craton Abyssal hills Abyssal plain Oceanic crust (lithosphere) Continental shelf Continental slope Continental rise Slide 8 The Earth Beneath Your Feet Is Moving (1) Convection cells, or currents Tectonic Plates Lithosphere Slide 9 The Earth Beneath Your Feet Is Moving (2) Three types of boundaries between plates Divergent boundaries Magma Oceanic ridge Convergent boundaries Subduction zone Trench Transform boundaries: San Andreas fault Slide 10 The Earths Crust Is Made Up of a Mosaic of Huge Rigid Plates: Tectonic Plates Fig. 14-3, p. 348 Slide 11 Spreading center Ocean trench Subduction zone Oceanic crust Continental crust Material cools as it reaches the outer mantle Cold dense material falls back through mantle Hot material rising through the mantle Mantle convection cell Two plates move towards each other. One is subducted back into the mantle on a falling convection current. Mantle Hot outer core Inner core Slide 12 The Earths Major Tectonic Plates Fig. 14-4, p. 349 Slide 13 EURASIAN PLATE NORTH AMERICAN PLATE JUAN DE FUCA PLATE CARIBBEAN PLATE AFRICAN PLATE INDIA PLATE PACIFIC PLATE COCOS PLATE COCOS PLATE SOUTH AMERICAN PLATE ARABIAN PLATE PHILIPPINE PLATE CHINA SUBPLATE ANATOLIAN PLATE PACIFIC PLATE NAZCA PLATE SOMALIAN SUBPLATE AUSTRALIAN PLATE SCOTIA PLATE ANTARCTIC PLATE Divergent plate boundaries Convergent plate boundaries Transform faults Slide 14 The San Andreas Fault as It Crosses Part of the Carrizo Plain in California, U.S. Fig. 14-5, p. 350 Slide 15 Some Parts of the Earths Surface Build Up and Some Wear Down Internal geologic processes Generally build up the earths surface External geologic processes Weathering Physical, chemical, and biological Erosion Wind Flowing water Human activities Glaciers Slide 16 Volcanoes Release Molten Rock from the Earths Interior Volcano Fissure Magma Lava 1991: Eruption of Mount Pinatubo Benefits of volcanic activity Slide 17 Creation of a Volcano Fig. 14-6, p. 351 Slide 18 Fig. 14-6b, p. 351 Extinct volcanoes Eruption cloud Ash Acid rain Ash fl ow Lava fl ow Mud fl ow Landslide Central vent Magma conduit Magma reservoir Slide 19 Earthquakes Are Geological Rock-and-Roll Events (1) Earthquake Seismic waves Focus Epicenter Magnitude Amplitude Slide 20 Earthquakes Are Geological Rock-and-Roll Events (2) Richter scale Insignificant: 8.0 Largest recorded earthquake: 9.5 in Chile in 1960 Slide 21 Major Features and Effects of an Earthquake Fig. 14-7, p. 351 Slide 22 Fig. 14-7a, p. 351 Liquefaction of recent sediments causes buildings to sink Two adjoining plates move laterally along the fault line Earth movements cause fl ooding in low-lying areas Landslides may occur on hilly ground Shock waves Focus Epicenter Slide 23 Earthquake Risk in the United States Figure 16, Supplement 8 Slide 24 World Earthquake Risk Figure 17, Supplement 8 Slide 25 Earthquakes on the Ocean Floor Can Cause Huge Waves Called Tsunamis Tsunami, tidal wave Travels several hundred miles per hour Detection of tsunamis Buoys in open ocean December 2004: Indian Ocean tsunami Magnitude 9.15 and 31-meter waves at shore Role of coral reefs and mangrove forests in reducing death toll Slide 26 Formation of a Tsunami and Map of Affected Area of Dec 2004 Tsunami Fig. 14-8, p. 352 Slide 27 Earthquake in sea fl oor swiftly pushes water upwards, and starts a series of waves Waves move rapidly in deep ocean reaching speeds of up to 890 kilometers per hour. As the waves near land they slow to about 45 kilometers per hour but are squeezed upwards and increased in height. Waves head inland causing damage in their path. Undersea thrust fault Upward wave Bangladesh IndiaMyanmar Thailand Sri Lanka Malaysia Earthquake Sumatra Indonesia December 26, 2004, tsunami Slide 28 Shore near Gleebruk in Indonesia before and after the Tsunami on June 23, 2004 Fig. 14-9, p. 353 Slide 29 14-2 How Are the Earths Rocks Recycled? Concept 14-2 The three major types of rocks found in the earths crustsedimentary, igneous, and metamorphicare recycled very slowly by the process of erosion, melting, and metamorphism. Slide 30 There Are Three Major Types of Rocks (1) Minerals Element or inorganic compound in earths crust Usually a crystalline solid Regular and repeating arrangement of atoms Rock Combination of one or more minerals Slide 31 There Are Three Major Types of Rocks (2) 1.Sedimentary Sediments from eroded rocks or plant/animal remains Transported by water, wind, gravity Deposited in layers and compacted Sandstone Shale Dolomite Limestone Lignite Bituminous coal Slide 32 There Are Three Major Types of Rocks (3) 2.Igneous Forms below or at earths surface from magma Granite Lava rocks 3.Metamorphic Preexisting rock subjected to high pressures, high temperatures, and/or chemically active fluids Anthracite Slate Marble Slide 33 The Earths Rocks Are Recycled Very Slowly Rock cycle Slowest of the earths cyclic processes Slide 34 Natural Capital: The Rock Cycle Fig. 14-10, p. 354 Slide 35 Erosion Transportation Weathering Deposition Igneous rock Granite, pumice, basalt Sedimentary rock Sandstone, limestone Heat, pressure Cooling Heat, pressure, stress Magma (molten rock) Melting Metamorphic rock Slate, marble, gneiss, quartzite Slide 36 14-3 What Are Mineral Resources, and What Are their Environmental Effects? Concept 14-3 We can make some minerals in the earths crust into useful products, but extracting and using these resources can disturb the land, erode soils, produce large amounts of solid waste, and pollute the air, water, and soil. Slide 37 We Use a Variety of Nonrenewable Mineral Resources (1) Mineral resource Can be extracted from earths crust and processed into raw materials and products at an affordable cost Metallic minerals Nonmetallic minerals Ore Contains profitable concentration of a mineral High-grade ore Low-grade ore Slide 38 We Use a Variety of Nonrenewable Mineral Resources (2) Metallic mineral resources Aluminum Iron for steel Copper Nonmetallic mineral resources Sand, gravel, limestone Reserves: estimated supply of a mineral resource Slide 39 Some Environmental Impacts of Mineral Use Advantages of the processes of mining and converting minerals into useful products Disadvantages Slide 40 The Life Cycle of a Metal Resource Fig. 14-11, p. 355 Slide 41 MiningMetal ore Separation of ore from waste material SmeltingMelting metal Conversion to product Discarding of product Recycling Slide 42 Surface mining Metal oreSeparation of ore from gangue Smelting Melting metal Conversion to product Discarding of product Recycling Stepped Art Fig. 14-11, p. 355 Slide 43 Extracting, Processing, Using Nonrenewable Mineral and Energy Resources Fig. 14-12, p. 356 Slide 44 Natural Capital Degradation Extracting, Processing, and Using Nonrenewable Mineral and Energy Resources StepsEnvironmental 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 Slide 45 There Are Several Ways to Remove Mineral Deposits (1) Surface mining Shallow deposits removed Overburden removed first Spoils: waste material Subsurface mining Deep deposits removed Slide 46 There Are Several Ways to Remove Mineral Deposits (2) Type of surface mining used depends on Resource Local topography Types of surface mining Open-pit mining Strip mining Contour strip mining Mountaintop removal Slide 47 Natural Capital Degradation: Open-Pit Mine in Arizona Fig. 14-13, p. 357 Slide 48 Area Strip Mining in Wyoming Fig. 14-14, p. 357 Slide 49 Natural Capital Degradation: Contour Strip Mining Fig. 14-15, p. 358 Slide 50 Undisturbed land Overburden Pit Bench Spoil banks Slide 51 Mining Has Harmful Environmental Effects (1) Scarring and disruption of the land surface E.g., spoils banks Mountain top removal for coal Loss of rivers and streams Air pollution Groundwater disruption Biodiversity decreased Slide 52 Mining Has Harmful Environmental Effects (2) Subsurface mining Subsidence Acid mine drainage Major pollution of water and air Effect on aquatic life Large amounts of solid waste Slide 53 Spoils Banks in Germany from Area Strip Mining Fig. 14-16, p. 358 Slide 54 Mountaintop Coal Mining in West Virginia Fig. 14-17, p. 359 Slide 55 Ecological Restoration of a Mining Site in Indonesia Fig. 14-18, p. 360 Slide 56 Removing Metals from Ores Has Harmful Environmental Effects (1) Ore extracted by mining Ore mineral Gangue = waste material Smelting using heat or chemicals Air pollution Water pollution Slide 57 Removing Metals from Ores Has Harmful Environmental Effects (2) Liquid and solid hazardous wastes produced Use of cyanide salt of extract gold from its ore Summitville gold mine: Colorado, U.S. Slide 58 Individuals Matter: Maria Gunnoe West Virginia environmental activist Won $150,000 Goldman Environmental Prize for efforts against mountaintop coal mining Her home Flooded 7 times Coal sludge in yard Well contaminated Slide 59 14-4 How Long Will Supplies of Nonrenewable Mineral Resources Last? Concept 14-4A All nonrenewable mineral resources exist in finite amounts, and as we get closer to depleting any mineral resource, the environmental impacts of extracting it generally become more harmful. Concept 14-4B Raising the price of a scarce mineral resource can lead to an increase in its supply, but there are environmental limits to this effect. Slide 60 Mineral Resources Are Distributed Unevenly (1) Most of the nonrenewable mineral resources supplied by United States Canada Russia South Africa Australia Sharp rise in per capita use in the U.S. Slide 61 Mineral Resources Are Distributed Unevenly (2) Strategic metal resources Manganese (Mn) Cobalt (Co) Chromium (Cr) Platinum (Pt) Slide 62 Supplies of Nonrenewable Mineral Resources Can Be Economically Depleted (1) Future supply depends on Actual or potential supply of the mineral Rate at which it is used Slide 63 Supplies of Nonrenewable Mineral Resources Can Be Economically Depleted (2) When it becomes economically depleted Recycle or reuse existing supplies Waste less Use less Find a substitute Do without Depletion time: time to use a certain portion of reserves Slide 64 Natural Capital Depletion: Depletion Curves for a Nonrenewable Resource Fig. 14-19, p. 361 Slide 65 Mine, use, throw away; no new discoveries; rising prices A Recycle; increase reserves by improved mining technology, higher prices, and new discoveries B Production Recycle, reuse, reduce consumption; increase reserves by improved mining technology, higher prices, and new discoveries C Depletion time A Depletion time B Depletion time C Present Time Slide 66 A Mine, use, throw away; no new discoveries; rising prices Depletion time A Recycle; increase reserves by improved mining technology, higher prices, and new discoveries B Depletion time B Recycle, reuse, reduce consumption; increase reserves by improved mining technology, higher prices, and new discoveries C Depletion time C Production Present Time Stepped Art Fig. 14-19, p. 361 Slide 67 Market Prices Affect Supplies of Nonrenewable Minerals Subsidies and tax breaks to mining companies keep mineral prices artificially low Does this promote economic growth and national security? Scarce investment capital hinders the development of new supplies of mineral resources Slide 68 Case Study: The U.S. General Mining Law of 1872 Encouraged mineral exploration and mining of hard- rock minerals on U.S. public lands Developed to encourage settling the West (1800s) Until 1995, land could be bought for 1872 prices Companies must now pay for clean-up Slide 69 Colorado Gold Mine Must Be Cleaned up by the EPA Fig. 14-20, p. 363 Slide 70 Is Mining Lower-Grade Ores the Answer? Factors that limit the mining of lower-grade ores Increased cost of mining and processing larger volumes of ore Availability of freshwater Environmental impact Improve mining technology Use microorganisms, in situ Slow process What about genetic engineering of the microbes? Slide 71 Can We Extend Supplies by Getting More Minerals from the Ocean? (1) Mineral resources dissolved in the ocean -- low concentrations Deposits of minerals in sediments along the shallow continental shelf and near shorelines Slide 72 Can We Extend Supplies by Getting More Minerals from the Ocean? (2) Hydrothermal ore deposits Metals from the ocean floor: manganese nodules Effect of mining on aquatic life Environmental impact Slide 73 Natural Capital: Hydrothermal Deposits Fig. 14-21, p. 364 Slide 74 Black smoker White smoker Sulfide deposits Magma White clam White crab Tube worms Slide 75 14-5 How Can We Use Mineral Resources More Sustainability? Concept 14-5 We can try to find substitutes for scarce resources, reduce resource waste, and recycle and reuse minerals. Slide 76 We Can Find Substitutes for Some Scarce Mineral Resources (1) Materials revolution Nanotechnology Ceramics High-strength plastics Drawbacks? Slide 77 We Can Find Substitutes for Some Scarce Mineral Resources (2) Substitution is not a cure-all Pt: industrial catalyst Cr: essential ingredient of stainless steel Slide 78 Science Focus: The Nanotechnology Revolution Nanotechnology, tiny tech Uses Nanoparticles Are they safe? Investigate potential ecological, economic, health, and societal risks Develop guidelines for their use until more is known about them Slide 79 We Can Recycle and Reuse Valuable Metals Recycling Lower environmental impact than mining and processing metals from ores Reuse Slide 80 Aluminum Cans Ready for Recycling Fig. 14-22, p. 366 Slide 81 We Can Use Mineral Resources More Sustainability How can we decrease our use and waste of mineral resources? Pollution and waste prevention programs Slide 82 Solutions: Sustainable Use of Nonrenewable Minerals Fig. 14-23, p. 366 Slide 83 Case Study: Pollution Prevention Pays Begun in 1975 by 3M company, a very large manufacturing company Redesigned equipment and processes Fewer hazardous chemicals Recycled or sold toxic chemical outputs Began making nonpolluting products Company saved $1.2 billion Sparked cleaner production movement Slide 84 Three Big Ideas 1.Dynamic forces that move matter within the earth and on its surface recycle the earths rocks, form deposits of mineral resources, and cause volcanic eruptions, earthquakes, and tsunamis. 2.The available supply of a mineral resource depends on how much of it is in the earths crust, how fast we use it, mining technology, market prices, and the harmful environmental effects of removing and using it. Slide 85 Three Big Ideas 3.We can use mineral resources more sustainably by trying to find substitutes for scarce resources, reducing resource waste, and reusing and recycling nonrenewable minerals.