1 / 23

BAESI: California’s Resources

BAESI: California’s Resources. Earth Materials. Earth Materials Focus Questions. Why are Earth materials important? What is a mineral ? What’s the difference between a mineral and a rock?. What is a Mineral?. A mineral is a naturally-occurring solid

frye
Télécharger la présentation

BAESI: California’s Resources

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BAESI: California’s Resources Earth Materials

  2. Earth MaterialsFocus Questions • Why are Earth materials important? • What is a mineral? • What’s the difference between a mineral and a rock?

  3. What is a Mineral? A mineral is a naturally-occurring solid with a definite (but generally not fixed) chemical composition and an orderly internal arrangement of atoms (crystalline). Examples of chemical formulas for minerals: Quartz: SiO2 Pyrite: FeS2

  4. Crystalline Halite - NaCl Definite chemical composition Orderly arrangement of atoms

  5. How Many Minerals Are There?> 4,000 - but only a few are common in rocksRelative abundance of elements in Earth’s crust Silicates are mostcommon

  6. Rocks: Aggregates of Minerals http://www.geo.wvu.edu/~jtoro/geol101/minerals/Granitic_Minerals.jpg

  7. Mineral Identification • What properties can be used to identify minerals? • What do you observe?

  8. Physical properties used to identify minerals • Color • Streak • Luster • Hardness • Cleavage/fracture • Specific gravity (“heft’) • Reaction with dilute HCl (or vinegar) • Magnetism • Crystal habit or form

  9. Moh’s Scale of Hardness

  10. Examples of Cleavage

  11. FORMATION OF MINERAL DEPOSITS Source: Steve Nelson, Tulane Univ. Concentration factor: the increase in concentration of a mineral required to form an ore. Is this a constant?

  12. Types of Mineral Deposits • Hydrothermal mineral deposits form in association with magma and water Gold, cinnabar • Residual mineral deposits formed by weathering reactions at the earth’s surface. Bauxite (aluminum ore) in tropical soil • Placer deposits are sorted and distributed by flow of transporting media such as water, wind and ice; Sand and gravel; gold, diamonds • Sedimentary mineral deposits are precipitated from a solution, typically sea water (evaporites) Salt, borates • Mineral deposits form in association withmetamorphism • Graphite, garnet

  13. Mineral Resources: Overview • Metallic Minerals • Non-ferrous: Copper, Zinc, Tin, Lead, Aluminum, Titanium, Manganese, Magnesium, Mercury, Vanadium, Molybdenum, Tungsten, Silver, Gold, Platinum • Energy Resources • Fossil Fuels: Coal, Oil, Natural Gas • Uranium • Geothermal Energy • Building Stone, Sand, Gravel, Limestone • Non-metallic Minerals Sulfur, Gypsum, Coal, Barite, Salt, Clay, Feldspar, Gem Minerals, Abrasives, Borax, Lime, Magnesia, Potash, Phosphates, Silica, Fluorite, Asbestos, Mica • Metallic Minerals • Ferrous: Iron and Steel, Cobalt, Nickel

  14. Mineral Resources • Are mineral resources renewable or nonrenewable? • Why?

  15. http://www.mii.org/images/baby.jpg http://www.mii.org/images/baby.jpg

  16. Mineral Resources • Metals – iron, aluminum, copper, lead, zinc, nickel, cobalt, gold, silver, or platinum • Nonmetallic Minerals – sulfides, lime (calcium carbonate), sulfur, halite, clay, gypsum, or potash • Rock resources – most abundant quantity of earth resources we use • Sand, gravel, limestone, quartz-rich sand, marble, granite, and sandstone • Energy Resources • Fossil Fuels: Coal, Oil, Natural Gas • Uranium • Geothermal Energy

  17. Uses for some minerals and rocks • Hematite • Quartz • Graphite • Gypsum • Calcite • Galena

  18. Minerals Hematite: Ore of iron used to make steel; pigment Quartz (silicon dioxide) – Primary ingredient in glass Graphite: Pencil lead; lubricant Gypsum: Plaster of paris; drywall; wallboard Calcite: In toothpastes, cements, and mortars Galena: Ore of lead Rocks Obsidian - Ornamental stone, anciently used as a tool, jewelry, brain surgery scalpel blade Granite - Used in buildings Pumice - An abrasive in soaps and in emery boards. Sandstone - Used in construction Limestone - Used to manufacture cement, paper, and the packaging of chewing gum

  19. California’s Non-fuel Mineral Production, 2007

  20. Mineral Resources: Distribution • Globally, very un-even distribution • Some countries have plenty – export nations • Some countries have none – import nation • Un-even distribution: wars fought

  21. World Mineral Supply • Technology often allows more access to difficult or low grade ore deposits • Less developed nations are striving to achieve comparable standards of living as the technologically advanced countries enjoy • Future mineral-resource shortages will occur and cause international tension • Recycle • Reduce consumption rate

  22. Environmental Impacts of Mining • Air and water pollution • Occupational hazard • Underground mining • Generally hard to see where they are located Old, abandoned, and forgotten mines are still a problem • Surface Mining: Land Disturbance • Open-Pit • Strip • Spoil banks - pollution

  23. Impacts: Mineral Processing • Ore rock is ground or crushed for extraction • The fine waste material is placed in tailings • The tailings are exposed to wind and weather • Acid mine drainage • Harmful elements such as mercury, arsenic, cadmium, or uranium can leached out • The surface and subsurface water systems are too often contaminated • Chemicals used in ore extraction are toxic Example: cyanide to leach gold • Smelting ores to extract metals, often produce metal laden exhaust gas or ash, sulfur oxide and acid rain pollution

More Related