Chapter 6 - Lithosphere

• Layers of the Earth - Crust

  Composition - solid, outmost layer composed of mainly silicate rocks

  Properties - most rigid layer
• Layers of the Earth - Mantle

  Composition - can partially flow and conduct heat

  Properties - flows relatively easily and has very little strength
• Layers of the Earth - Asthenosphere

  Composition - convection currents due to its ability to effectively conduct heat

  Properties - can flow but at very low rates
• Layers of the Earth - Outer core

  liquid layer of Earth. It's made of iron and nickel, and is responsible for the planet's magnetic field.
• What is a regolith?

  Solid particles that remain after weathering
• What is a solute?

  dissolved substance
• What is an alluvial?

  materials such as weathered rock particles deposited by a river
• What is sedimentary?

  material or processes that involve material being carried by air or water and then deposited
• What are evaporitic rocks?(Sedimentary mineral deposits)

  rocks are formed due to evaporation of saline water
• What are inorganic rocks? (Sedimentary mineral deposits)

  form from CaCO3, by chemical leaching
• What are organic rocks?(Sedimentary mineral deposits)

  form due to decomposition of organic remains under temperature and pressure
• Evaporite deposit

  Requires a "locked off" area where the evaporation rate is higher than net water input
• Biological deposits

  Fossil fuels are produced from dead organisms partially decaying in anaerobic conditions
• Chemical deposits

  Are found on the ocean floor

  Take millions of years to grow and therefore extraction is not sustainable

  Very concentrated ores
• What is Igneous?

  Process which rocks are created by the cooling and hardening of magma
• What is a Batholith?

  large underground mass of solidified molten magma
• What is metamorphic?

  rocks changed by intense heat and pressure but without fully melting
• What is Hydrothermal?

  Processes of deposits associated with hot water
• What are intrusive rocks?

  cool slowly inside the ground and crystals have time to form
• What are extrusive rocks?

  cool quickly on the surface and crystals don't have time to form
• What are hydrothermal deposits?

  presence of hot water to transport water

  interconnected openings in the rocks to allow solutions to move
• What are metamorphic deposits?

  existing rocks under high pressure and temperature conditions.
• What is a resource?

  All the mineral that is technically available for exploitation.

  Cannot be extracted now but may be due to advancements in technology
• What are reserves?

  amount of a resource that can be exploited now economically using existing technology
• What is a reservoir

  storage location for any material
• Mine viability - market economics

  market price is controlled by the demand for the mineral, how much is produced and the costs of extraction
• Mine viability - Land use conflicts

  if more money can be made by another land use then extraction won't happen, reserves have a fixed location
• Mine viability - extraction costs

  overburden rock that needs to be removed before extraction

  deeper = more costly
• Mine viability - hydrology

  as depth increases , the amount of water that flows into the mine cost of pumping is very high and energy intensive
• Exploration - nature of problem

  land clearance and noise surveys
• Land take - Nature of problem

  land required for mining not just for mine itself
• Habitat loss - nature of problem

  loss of species where mineral is extracted
• Habitat loss - solution

  new habitats created on completion of the extraction]
• Loss of amenity - nature of problem

  mining can damage aesthetic of community
• Loss of amenity -solution

  reducing by tree planting and buffer zones
• Subsidence - nature of problem

  caused by poor soil compaction
• Subsidence - solution

  leaving support pillars in mines
• Turbid drainage water - nature of problem

  mining produces particles that are carried away by river sources
• Turbid drainage water - solution

  sedimentation lagoons -> water stands still -> solids sink
• Advantages of extraction in Antarctica

  -> valuable mineral resources such as gold is there

  -> not hunting elephant seals for oil

  -> predictable environment and geology