2. What are the characteristics of a mineral? Solid Inorganic – not living Crystalline structure/pattern Definite chemical makeup – same elements/compounds Naturally occurring – not man-made
3. How are minerals used? Ore - valuable Gemstones/jewelry Nutrition Diamond drill bits Cleaning products Reclamation: fix the land after mining – return to original or better condition
4. How are rocks classified? Texture – mineral grains: coarse, medium, fine Mineral composition – more than 1 mineral Formation – how they are formed, not where they are found
5. The Rock Cycle Continual – no beginning, no end Rocks can travel any path Actions between changes… Look for key words
6. Sedimentary Rocks Sediment – bits of rock WEDCC: weathering (breaking down to create sediment), erosion (moving of sediment), deposition (dropping of sediment), compaction (squeezing of sediment), and cementation (sediment glued together after the evaporation of mineral solution) Can be formed from any type of rock
7. Sedimentary Rock Types Organic – once living material Chemical Clastic – cemented together Conglomerate, sandstone
8. Igneous Rocks Melting, cooling, and hardening Intrusive: magma – below surface, cools slowly, large crystals; coarse-grained texture – granite Extrusive: lava, above surface, cools quickly, small crystals, fine-grained or glassy texture – basalt, obsidian
9. Metamorphic Rocks Heat – from mantle Pressure – from layers of rock above Foliated (banded, layered) and nonfoliated (nonbanded, not layered) Composition can actually be changed Can be formed from any rock type Gneiss
10. Fossils Remains or traces of once living things Mold (imprint), cast (rock fills in), petrified (mineral replacement - forests), amber, tar/asphalt (LeBrea Tar Pits) Trace fossils – evidence of activity (tail, footprint) Index fossils – short lifespan, widespread geographically, numerous: trilobyte and ammonite
11. Relative Age/Dating Approximate Index fossils date rock layers Superposition (older on bottom in geologic column) Original horizontality – undisturbed Uniformitarianism – gradual, consistent – past helps us understand present
12. Absolute Age/Dating Exact age in years Radioactive decay: rate of decay in radioactive element – unstable to stable (half life) Carbon-14: on once living organisms (carbon, organic) – up to 50,000 years
13. Geologic Time Breaks geologic time into manageable parts: eon, era, period, epoch Based on changes in fossil evidence (life changes) Paleozoic (largest mass extinction), Mesozoic (reptiles – dinosaurs), Cenozoic (mammals, now) Gaps in time – only a few organisms fossilized
14. Fossil Fuels From once living organisms; millions of years to form We rely on them Photochemical smog (worse in spring, summer), acidic precipitation (rain), worsens global warming/ozone damage Nonrenewable - depleting rapidly Coal, petroleum (oil), natural gas, gasohol
15. Alternative Energy Expensive to implement Less pollution Wind (renewable), biomass (organic, renewable), solar (Sun’s radiation, photocell, renewable), hydroelectric (Lake Lanier, dam, renewable), geothermal (renewable), nuclear (fission, nonrenewable, radioactivity?)
16. Conservation Use less Use what we do have more efficiently Recycle Water at night, don’t let the water run, carpool, turn the lights off, use energy-saver settings on appliances
17. Soil Conservation Prevent erosion of soil Dust Bowl – loss of topsoil due to erosion (wind) Cover crops (protect topsoil), contour plowing, crop rotation (prevent nutrient depletion), terracing (flat sections on hills), windbreaks (slow down wind)
