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Minerals & Mining

Minerals & Mining. Chapter 15. General Mining Law (1872). 1872 – do you think it was good or bad?? Encouraged settlement of western states. Anyone can stake a mining claim on federal lands, buy for $2.50 - $5 per acre, extract the resources, & keep all profits.

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Minerals & Mining

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  1. Minerals & Mining Chapter 15

  2. General Mining Law (1872) • 1872 – do you think it was good or bad?? • Encouraged settlement of western states • Anyone can stake a mining claim on federal lands, buy for $2.50 - $5 per acre, extract the resources, & keep all profits. • No provisions for environmental protection

  3. …General Mining Law (1872) More than 50 of the 100,000 to 500,000 abandoned mines in the US are Superfund sites! Cleanup of all Superfund mining sites will cost an estimated $12.5-$17.5 billion.

  4. Minerals • Elements or compounds of elements that occur naturally in Earth’s crust. • Ex: steel (mixture), aluminum, copper, concrete (mixture), sulfur, salt, quartz, gold, … you get it. • Changed the course of history… • Britain = explored for tin. • Bronze Age = ruled by the alloy of copper & tin. • New World = explored for gold & silver. • California = gold rush (1840s) • Rain forests destruction = gold

  5. Mineral Groups: Sulfides (S + another element) Oxides (O + metals) Halides (F, Cl, Br, I) Silicates (Si + O) Carbonates (C + O) Native Elements (any pure element) Can be: Metallic Nonmetallic Rocks = combo of minerals + other stuff Ore = rock that contains a large enough concentration of a mineral that makes it profitable to mine for. High-grade ore: large amounts of minerals Low-grade ore: low amounts of minerals. …Minerals NATURALLY OCCURRING INORGANIC SPECIFIC CHEM. COMP. SOLID DEF. CRYSTAL STRUCTURE

  6. Distribution & Formation • Widely distributed worldwide (see next slide) • Some countries have a lot, some have a little. =============================================== • Magmatic Concentration • Magma cools & separates into layers • Heavy (Fe, Mg) on bottom, Light (SiO2) on top • Hydrothermal Processes • Hot groundwater dissolves minerals & react with S, making sulfides • Sulfides aren’t soluble, so they settle out. • Sedimentation • Water transports weathered particles and deposits them as sediment • Evaporation • Salts & minerals are left behind when water evaporates.

  7. How is mining done? STEP 1: DISCOVER THEM! STEP 2: EXTRACT THEM! STEP 3: PROCESS & REFINE THEM! STEP 4: MAKE THEM INTO A PRODUCT!

  8. Step 1: DISCOVERY Aerial or Satellite photography Measure Earth’s magnetic field & gravity Geological knowledge of how minerals form Drill for samples & analyze composition Sea floor?? Detailed 3D maps!

  9. Step 2: EXTRACTION • 2 ways: Surface & Subsurface Mining! • Surface Mining (less $$, less danger) • Overburden must be removed • 4 Kinds: • Open-pit mining = dig a big hole to make a quarry. • Strip Mining = dig parallel trenches and create a spoil bank (dump new trench’s overburden in old trench) • Mountaintop Removal = BAD!!! • Dredging = chain buckets & draglines scrape underwater minerals • Subsurface Mining (more $$, more danger)

  10. Open-Pit Mine: Bingham Canyon, UT Largest man-made hole in the world 2.5 miles wide, 0.5 miles deep Material removed = 7X amount moved to create the Panama Canal

  11. Strip Mine: http://www.coal.ca/content/images/stories/stripmine.htm SPOIL BANK TRENCH

  12. Mountaintop Removal (MTR)

  13. “Strip Mining on Steroids” • Widespread in WV, KY, TN, VA, PA • Boston.com, 3/16/08: • “Short of a nationwide shift away from coal and toward renewable sources, the Appalachia activists would like to see Congress pass the Clean Water Protection Act. This bill would reverse one of the Bush administration's most damaging concessions to industry on the environmental front. The Environmental Protection Agency decided in 2002 that mountaintop-removal miners' practice of dumping their waste into stream beds did not violate the Clean Water Act of 1970. The EPA decided the material was "fill," not waste.”

  14. Step 2: EXTRACTION • Surface Mining (less $$, less danger) • Subsurface Mining (more $$, more danger) • Less damage to the environment (@ surface) • Can cause subsidence & even miners’ deaths. • 4 Kinds: • Shaft Mine = direct vertical shaft, hauled out in buckets. • Slope Mine = slanting passage, hauled out in cars. • Room-and-pillar= some coal left in place as pillars to prevent collapse. • Longwall = narrow tunnel supported by movable metal roof supports. Allowed to collapse after mining is completed.

  15. Step 3: PROCESSING • Smelting • Melting ore at high temperatures to help separate impurities from the molten metal. • Uses a Blast Furnace • Ore, coke, and limestone react with heat to create: • Purified molten iron (denser) • Iron Ore + Coke = molten iron + carbon dioxide • Impurities (“Slag”) (less dense) • Limestone + Impurities = slag • Exhaust gases are dangerous!

  16. Step 4: CREATE PRODUCT … that means… Create a Product!! Duh!

  17. Environmental Implicationsp.336-340 • Get in groups of 6. • Choose a partner within your group. • Each pair summarizes one of the following: • 1 – Mining & the Environment (& c-b analysis) • 2 – Environmental Impacts of Refining Minerals • 3 – Restoration of Mining Lands (& creative approaches) • Vocab is key!!! …8min total! • Teach your Home Group! …3min each!

  18. Increasing our Mineral Suppliesp.340-344 • Locating & Mining New Deposits • Minerals in Antarctica • Minerals from the Ocean • Advanced Mining Techniques

  19. Increasing our Supplies…Locating and Mining New Deposits • Sometimes we know there are resources out there… but they’re inaccessible. • Malaria in Indonesia, Ice in Antarctica, High sedimentation in Amazon Basin • Create new technologies • Dig 10km below surface, go through ice sheets, etc. • Possible to find new resources?? USGS: sure!

  20. Increasing our Supplies…Minerals in Antarctica • To date, no substantial mineral deposits have been found in Antarctica. • But we might find some! • FYI – nobody owns Antarctica… so the rules can get sticky when people want to exploit resources. • ANTARCTIC TREATY – 1961 • Limits activity in Antarctica to peaceful uses such as scientific studies. • Environmental Protection Protocol to the Antarctic Treaty (Madrid Protocol) – 1990 • Moratorium on mineral exploration and development for >50yrs • People are already ruining Antarctica’s fragile ecosystem… science, tourism, noise, pollution…

  21. Increasing our Supplies…Minerals from the Ocean • What’s there? • Minerals from the seawater (evaporation) – NaCl, Br • Manganese Nodules! (p.344 in book) – Pacific has lots! • How do we get them? • Dredging mostly. $$$$$$$$$ • Problems? • BAAAAD for the marine life. • Who has the rights? It’s in international waters! • Controversy: • Some: it’s inevitable… Let’s mine it. • Others: so much ecological damage… Let’s declare it off-limits.

  22. China denies reports on halting export of rare earth

  23. Increasing our Supplies…Advanced Mining Technologies • Use more low-grade mineral deposits. • $$$$$$$$$$$$$$$ • Causes greater land disruption • Produces far more pollution than high-grade ores • In arid regions, lots of water needs to be pumped in to help with the mining process. • Biomining • Microorganisms can extract minerals from low-grade ores • Copper mining uses it. • They help!! • 90% recovery of gold with them • 75% recovery without them.

  24. Expanding our Supplies by Substitution and Conservation • Finding Mineral Substitutes • Use inexpensive, abundant materials instead! • Old=Tin. New=plastic, glass, aluminum. • Old=Copper wires. New=fiber optics (glass). • Mineral Conservation – important!! (they’re nonrenewable!) • Reuse & Recycle • Changing our Mineral Requirements • Become a low-waste society! • Sustainable manufacturing (minimize waste in industry) • Dematerialization • Decrease weight of products.

  25. “Throwaway” Mentality

  26. Sustainable Manufacturing Traditional Flow of Minerals Low-Waste Society Flow of Minerals

  27. RELEVANT LEGISLATION • General Mining Law (1872) • Allowed people to “stake claims” & make profit • Surface Mining Control and Reclamation Act (1977) • Required reclamation of previously mined areas • Only from coal mining!! • Antarctic Treaty (1961) • Limits activity in Antarctica to peaceful uses such as scientific studies • Convention on the Regulation of Antarctic Mineral Resource Activities (1980s) • Never ratified – would have permitted exploitation of Ant. minerals • Environmental Protection Protocol to the Antarctic Treaty (Madrid Protocol) (1990) • Moratorium on mineral exploration & development for >50 years • Designated Antarctica & its marine ecosystem as a “natural reserve dedicated to peace and society”

  28. Chapter 17 LAND RESOURCES & CONSERVATION

  29. Role of Rural Lands Ecosystem services Wildlife habitat, flood/erosion control, ground water recharge Breaks down pollutants & recycles waste Provide habitat for organism Recreational/spiritual uses Hiking, boating, sport hunting, fishing Used as bench marks for scientists to determine the impact of human activity

  30. Land ownership in US 55% owned privately 3% owned by Native Americans ~35% owned by the Federal Govt. Includes ecosystems from tundra to desert Contains important resources such as minerals, fossil fuels, historical significance or critical habitat Mostly in Alaska and 11 western states Managed by: 1. US Department of the Interior Bureau of Land Management (BLM) Fish and Wildlife Service (FWS) National Park Service (NPS) 2. Department of Agriculture U.S. Forest Service (USFS) ~7% owned by state/local Govt.

  31. Important Land Laws Wilderness Act (1964) Preserves (natural & unchanged) federally owned land that: retains its primeval character lacks permanent improvements or human dev’t Given the highest protection of any federal land Mostly in the west or Alaska Restrict # of people allowed in these areas to decrease erosion, pollution & human impact

  32. The Wild & Scenic Rivers Act (1968) Protects rivers with outstanding beauty, recreational value, unique geologic features, important wildlife

  33. National Parks Service Protect land & biological diversity in an unimpaired condition 385 sites (57 of them are National Parks) Many parks are threatened Human Activities- littering, graffiti, pollution, development around parks Large mammal population decrease (Bears) Large mammal population increase (Elk) Parks are now managed using Natural Regulation Populations are allowed to fluctuate naturally due to weather or predators Fires are not suppressed unless they threaten people Park managers DO control exotic species invasion

  34. FORESTS Occupy less than 1/3 of Earth’s surface Supply: Fuel, timber, paper products, nuts, mushrooms, fruits, medicines Provide many ecosystem services Influence local climate - Transpiration Regulating global biogeochemical cycles Act as “sinks” for CO2 Hold soil in place reducing erosion/mudslides Watersheds: Absorb, hold and slowly release water Controls flooding & droughts Animal habitat

  35. FOREST MANAGMENT Most “managed” forests are monocultures where trees are planted in rows and are of one variety All trees are the same age & size More prone to insects and diseases Insecticides & fungicides are used Monocultures can’t support large food webs

  36. Sustainable Forestry Seeks to: Conserve forests for long-term commercial timber harvest Sustain biodiversity by… Provide improved habitat for many species Decrease soil erosion Preserve watersheds COOPERATION is crucial! environmentalists government officials • loggers • farmers

  37. Sustainable Logging Practices: Unlogged areas are saved as sanctuaries Wildlife corridors are created (zones that connect isolated unlogged areas) Provide escape routes so animals can interbreed (help reduce extinction) Large animals can maintain large territories. wildlife corridor

  38. Harvesting Trees 5 Countries harvest the most trees US, Canada, Russia, China, Brazil What happens to harvested trees? 55% are burned Fuel wood or made into charcoal (partially burn w/o O2) Very important for developing nations 45% used for paper/wood products in highly developed nations Harvesting Methods Selective cutting Shelter wood cutting Seed tree cutting Clearcutting

  39. 1. Selective Cutting Mature trees are cut individually or in small clusters while the rest of the forest remains intact. Remaining trees fill in with saplings Animals don’t lose habitat

  40. 2. Shelterwood Cutting Some mature trees are harvested, leaving some to provide protection/shade for young trees and seedlings. The remaining mature trees are harvested once regeneration is well established. Little soil erosion

  41. 3. Seed Tree Cutting Almost all trees are harvested from an area A few desirable trees are left to provide seeds for the regeneration of the forest.

  42. 4. Clearcutting Removal of all trees from an area Area is allowed to reseed and regenerate naturally or is planted Timber companies prefer because it is cost effective. Destroys habitat & causes fragmentation Massive soil erosion issues LOGGING ROAD MUDSLIDE

  43. Deforestation Temporary or permanent clearance of large expanses of forest for agriculture/other uses World decrease of 37 Million acres yearly Causes: Drought, land clearing, expansion of agriculture, construction of roads, tree harvests, insects, disease Threatens indigenous people Results in decreased soil fertility through rapid leaching Uncontrolled soil erosion Sedimentation of waterways (harms fisheries) Extinction of species Global Temp Increase from more carbon/CO2 released Regional/global climate changes – less transpiration “If there isn’t a rainforest, there isn’t rain and then there is no river” Sean Connery in Medicine Man Only write these facts if you don’t know them

  44. Why are Tropical Forest Disappearing? More people need more food… …agricultural expansion!! Economic, social and governmental factors Amazonian Deforestation Subsistence Agriculture: (~60% of deforestation) Slash & Burn Agriculture- high yield at first, then very poor Commercial Logging: for exports (~20%) Cattle Ranching: Provide rangeland (~12%)

  45. Tropical Dry Forests Tropical areas with a wet & dry season Disappearing primarily for fuel Wood is used to make charcoal – important for developing countries Boreal Forests Coniferous evergreen trees Alaska, Canada, Scandinavia & N. Russia Cover 11% of Earth (world’s largest biome) Primary source of world’s industrial wood and wood fiber Estimated annual loss: Area 2x the size of the Amazonian Rainforests of Brazil Logging in Canada seems to be unsustainable.

  46. UNITED STATES FORESTS 57% privately owned; 20% US Gov.; 15% Corporations; 8% State & local Gov. Privately owned forests can be protected through the Forest Legacy Program Landowner grants a conservation easement US Gov. buys the land, agreeing not to develop it for a certain number of years National Forests have multiple uses. timber, livestock, water & watershed protection, mining, recreation & habitat Issues confrontations over multiple uses building of logging roads with tax revenues clear cutting

  47. Rangelands Temperate & Tropical Grasslands Predominant vegetation includes grasses, forbs, and shrubs Provide fodder for livestock Animals eat the leafy shoots of the grass and the fibrous roots continue to develop, allowing the plant to recover and re-grow Can actually encourage greater plant diversity Cannot exceed carrying capacity Overgrazed land BAD!!!! Can lead to Desertification: rangeland converted to desert due to drought and or overgrazing

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