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Do Now 3-25-14. What are natural resources? What causes precession (why is the earth tilted)? What is a constant? What powers the rock cycle and plate tectonics?. Mineral Resources. If it’s not grown, it’s mined!. Answer these in your notes…. What do you know about mining?
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Do Now 3-25-14 • What are natural resources? • What causes precession (why is the earth tilted)? • What is a constant? • What powers the rock cycle and plate tectonics?
Mineral Resources If it’s not grown, it’s mined!
Answer these in your notes… • What do you know about mining? • What are some advantages of mining you know of? • What are some disadvantages of mining you can think of?
Natural Resources • Renewable: can be replaced over short time (months, years, decades) • Non-renewable: takes thousands of years to form and accumulate
Formation of Mineral Deposits • Igneous: crystallize from magma • Ore: metallic mineral that can be mined for a profit • Hydrothermal: dissolve into hot water, and separate back out as it cools • Placer: Rocks weather and erode (break down and move), and denser elements settle to the bottom
Mining • The extraction of valuable minerals or other geological materials from the earth. Surface/Open-pit Mining • Layers of rock, soil, and vegetation are removed to uncover mineral deposits
How did Charlotte get to be the city it is? • Charlotte started off as a small village • In 1799 12-year old Conrad Reed found a 17 pound rock that was nearly solid gold(would be $481,440 at $1770 per ounce) • The Charlotte Mint opened in 1837 to mint money (now the Mint Museum) • Charlotte lead the nation in gold mining until 1848 (California gold rush) • Now Charlotte is 2nd largest banking city in U.S. (behind NYC)
Mountain-Top Removal • Has been called Strip-Mining on Steroids • There are 6 main components
1. Clearing • Before mining can begin, all topsoil and vegetation must be removed. Because coal companies frequently are responding to short-term fluctuations in the price of coal, these trees are often not even used commercially in the rush to get the coal, but instead are burned or sometimes illegally dumped into valleys.
2. Blasting • Many Appalachian coal seams lie deep below the surface of the mountains. Accessing these seams through surface mining can require the removal of 500-800 feet or more of elevation. Blowing up this much mountain is accomplished by using millions of pounds of explosives.
3. Digging • Coal and debris is removed by using this piece of machinery, called a dragline. A dragline stands 22 stories high and can hold 24 compact cars in its bucket. These machines can cost up to $100 million, but are favored by coal companies because they displace the need forhundreds of jobs.
4. Dumping Waste • The waste from the mining operation, also known as overburden or spoil, is dumped into nearby valleys, burying streams. According to an EPA environmental impact statement, more than 1,000 miles of Appalachian streams were permitted to be buried as of 2001.
5. Processing • The coal is washed and treated before it is loaded on trains. The excess water left over from this process is called coal slurry or sludge and is stored in open coal impoundments. Coal sludge is a mix of water, coal dust, clay and toxic chemicals such as arsenic mercury, lead, copper, and chromium. • Impoundments are held in place by mining debris, making them very unstable.
6. Reclamation (or conversion of wasteland into land suitable for usage) • While reclamation efforts such as stabilization and re-vegetation are required for mountaintop removal sites, in practice, state agencies that regulate mining are generous with granting waivers to coal companies. Most sites receive little more than a spraying of exotic grass seed, but even the best reclamation provides no comfort to nearby families and communities whose drinking water supplies have been polluted and whose homes will be threatened by floods for the hundred or thousands of years it will require to re-grow a forest on the mined site.
Impact of Mining Positive Impacts Negative Consequences What Are Your Ideas?
Impact of Mining Positive Impacts Negative Consequences Destruction or near-destruction of the surrounding environment Pollution (especially water) Conflicts, especially over rare resources Not sustainable • Provides us with the minerals and resources we need to live our lives (coal for energy, gravel and rock for building, etc.) • Provides jobs in areas where they may not otherwise be available http://www.youtube.com/watch?v=XyzwCKoLhDo&feature=related http://www.youtube.com/watch?NR=1&v=O8WpxjwxGns&feature=endscreen http://www.worldcoal.org/coal/uses-of-coal/
Exit Ticket • How does coal affect the environment? • How does coal affect the lives of humans?