Chapter 16 Minerals: A Non-renewable Resource

Overview of Chapter 16 Introduction to Minerals Mineral Distribution and Formation How Minerals are Found and Extracted Environmental Impact of Minerals An International Perspective Increasing the Supply of Minerals Substitution and Conservation

Introduction to Minerals Human History – need and desire Rocks Naturally formed aggregates of minerals Metallic vs. nonmetallic (next slide  examples) Examples of Minerals Concrete (mixture of sand, gravel and limestone)

Introduction to Minerals Examples of Minerals Table salt (________________) Copper (___________)

Mineral Distribution and Formation Abundant minerals in crust Aluminum and iron Scarce minerals in crust Copper, chromium, and molybdenum Distributed _________________ across globe If found in low abundance, mining is not _____________

Formation of Mineral Deposits Result of natural processes As magma cools heavier elements (Fe and Mg) settle Responsible for deposits of Fe, Cu, Ni, Cr Minerals are carried and deposited by water heated deep in earth’s crust Weathered particles are transported by water and deposited as sediment on sea floor or shore Salts are left behind after water body dries up

How Minerals are Found, Extracted, and Processed 4 step process: Locate mineral deposit Mine extracts of mineral from ground Process mineral- refining it by concentrating it and removing impurities Convert purified mineral to make product

Discovering Mineral Deposits Scientists (geologists) use a variety of instruments and measurements Aircraft and satellite instruments that measure Earth’s magnetic field Combine this with ________________________ of how minerals are formed

Extracting Minerals ______________________ Mining Comparison… Mineral and energy resources are extracted near Earth’s surface by removing soil, subsoil and over-lying rock strata More common because _____________________________ Two kinds: open pit (next slide) and strip mining Mineral and energy resources are extracted from _______ _________________________ deposits Two kinds: shaft mine and slope mine Comparison…

Extracting Minerals- Open Pit Surface Mining

Processing Minerals Smelting- process in which __________ is melted at high temps to separate impurities from the molten metal Possible problem- the vent for exhaust gases is near top of the iron smelter

Environmental Impacts of Minerals Prone to erosion Must pump water out of mine to keep it dry Pollution caused when sulfuric acid and dissolved lead, arsenic or cadmium wash out of mines into nearby waterway Historically, the environmental cost has not been incorporated into the actual price of mineral products to consumers Developing vs. developed countries

Environmental Impacts of Refining Minerals

Environmental Impacts of Refining Minerals 80% or more of mined ore consists of impurities- called _____________ Contain _______ materials Smelting plants emit large amounts of air pollutants Also liquid and solid waste Requires a lot of _________________ (fossil fuels combustion)

Mining and the Environment Prone to _____________________ Wind erosion causes air pollution Water erosion pollutes nearby waterways and damages aquatic habitats Open-pit mining of gold and other minerals uses __________________________________ of water Lowers water table Water quality decreases as water become contaminated Has adverse effects on the numbers and kinds of aquatic life Toxic pulses Cost Benefit Analysis?

Case-In-Point Copper Basin, TN Copper Basin progressed from lush forests to a panorama of red, barren hills baking in sun How did this happen??? Mid19th century, copper ore discovered Deforestation and acid precipitation caused the ecological ruin of area in a few years 2001 agreement - goal is to have the entire area under plant cover early in 21st century Return of the forest ecosystem will take at least a century or two

Restoration of Mining Lands Goals: __________________________ lands- lands that have been degraded by mining; restoration involves: Filling in and grading the derelict land to its natural contours Plant vegetation to hold soil Main issue- lack of funding Surface Mining Control and Reclamation Act (1977)- requires reclamation of areas that were surface mined for coal No federal law

Restoration of Mining Land Creative Approaches Trap sediment and pollutants before they get into streams, improving water quality Expensive to create and maintain, but cost effective compared to using lime to decrease acidity Increases the pH of mine drainage as bacteria consume the manure Use of specific plants to absorb and accumulate toxic materials in soil Great potential

Minerals: An International Perspective Highly developed countries rely on mineral deposits in _________________________ countries They have exhausted their own supplies Governments in developing countries lack ________________________ resources to handle pollution Acid mine drainage Air and water pollution

North American Consumption of Selected Metals Most developed countries had rich resource bases  enable them to become ___________________________ Now depleted Large difference in the consumption of minerals between highly developed and developing countries US and Canada- have about 5.1% of population, consume about 25% of many of world’s metals China Industrialization increases the demand for minerals

Distribution vs. Consumption Chromium: Chromium is used for… No _________________________ for chromium in many of its important applications, including jet engine parts Industrialized nations that lack significant chromium deposits must import essentially all of their chromium Many countries have ___________________________ important minerals to reduce dependence on potentially unstable suppliers US- stockpiles of strategic minerals- titanium, tin, manganese, chromium, platinum, cobalt 

Will We Run Out of Important Metals? Mineral Reserves- Mineral Resources- Any undiscovered mineral deposits or known deposits of low grade ore that are currently unprofitable to extract The combination of mineral’s reserves and resources is its total resources

Will We Run Out of Important Minerals? Estimates of mineral reserves and resources fluctuate with economic, technological and political changes Very _________________ to forecast future mineral supplies Experts think mineral supplies will be ________________________ during 21st century Some minerals (mercury, tungsten, tin) may become increasingly scarce during this time Experts also think prices of even relatively plentiful minerals (Fe, Al) will ________________________

Increasing Supply of Minerals – Locating and Mining New Deposits Many known mineral deposits have not yet been exploited Ex: Malaria ridden forests of Indonesia Ex: polar regions Ex: 10km or deeper

Increasing Supply of Minerals – Minerals in Antarctica No _______________________ mineral deposits identified to date Geologists feel they will be discovered in near future No one owns Antarctica Antarctica Treaty (1961) Limits activity to ______________ uses (i.e. scientific studies) Madrid Protocol (1990) ______________________________ on mineral exploration and development for minimum of 50 years Is concern founded?

Increasing Supply of Minerals- Minerals from the Ocean May provide us with future supplies Extracting minerals from seawater Mining seafloor- Manganese nodules (below) Problems? UN Convention on the Law of the Sea

Advance Mining and Processing Technologies Special techniques to make use of large, low-grade mineral deposits world-wide Currently requires a lot of _____________________ Even with other technologies, limiting factors may include: ________________________________ Using microorganisms to extract minerals from low-grade ores

Finding Mineral Substitutes Important goal in _____________________ Driven by economics- cut costs! _____________________ expensive/scarce mineral resources for inexpensive/abundant ones Examples: Using plastic, glass or aluminum in place of tin Using plastic instead of lead and steel in telecommunications cables Using glass fibers instead of copper wiring in telephone cables

Mineral Conservation Includes ___________________________________ of existing mineral supplies Reuse- using items over and over again Reduces both mineral consumption and pollution Recycling- converting item into new product Common practice throughout industrialized world Reduces land destruction from mining Decreases energy consumption and pollution

Changing Our Mineral Requirements Must change out “_______________________” mentality Damaged or unneeded articles are thrown away _______________________________- the decrease in weight of products over time Quality decline?

Mineral Flow in an Industrial Society