Mineral Resources (gaps) Flashcards
Define mineral
A solid, naturally occurring inorganic substance
Define resource
Any physical material constituting part of Earth that people need and value.
Valuable material that we can extract, but may not be profitable.
Metals and minerals in a mobile phone:
- diamond - electrodes in batteries
- silicon - microchips
- salt - magnesium - casing
- mercury - touch screen
- nickel - electronic wiring
- borksite - LED backlight
- copper - electrical wiring
- tungsten - speakers and microphone
- lithium batteries
- arsenic microchips
Describe the rock cycle
Define sedimentary
Rock that has formed from sediment
Formed by the accumulation or deposition of mineral and organic particles
What are the 5 sedimentary processes?
- Evaporites
- Alluvial deposits
- Proterozoic marine sediments
- Secondary enrichment
- Biological deposits
Describe Proterozoic marine sediments
- 1.8 to 2.5 billion years ago in the ocean (occurred in early Proterozoic era)
- Photo-synthesisers increase oxygen in the atmosphere and ocean
- metals (such as Fe) come out of solution when oxidised - solids sink and deposit
- large deposits of valuable metals in sedimentary rock formed on the ocean floor
- rocks such as haemetite are rich in Fe
Describe how alluvial deposits (flow separation) can separate and concentrate valuable metals and minerals
- transferred by water
- different minerals deposited at different velocities
- denser drop first
Explain the process of secondary enrichment
- Rock exposed at the surface
- some metals oxidise (exposed to oxygen)
- go into solution
- solution infiltrates and percolates into ground
- when water (solution) reaches water table, conditions are now anaerobic and metals come out of solution (become concentrated in one place).
Describe how evaporites form
- Deposits that occur due to the evaporation of water
- most common are salt (hyaline) deposits
- bodies of water that are land locked
Explain how biological deposits can form sedimentary rocks, give 2 examples
- remains of living organisms
- limestone (calcite shells CaCO3) - used in cement and concrete
- coal (anaerobic decay of plants and and swamp deposits)
Define igneous
A rock having solidified from lava or magma
Explain how granite batholiths are formed
- Intrusion of magma into the crust
- large volume of magma (100s of km across) cools below the surface
- most batholiths are granite
- when it cools it becomes granite
Explain how Hydrothermal Metal Ores are deposited
- magma (batholith) rise through/into crust
- the surrounding rocks become super heated
- ground water superheated
- metals go into solution in hot water
- water (+metals in solution) move away from the batholiths along cracks and fissures
- water cools and metals come out of solution
- fractional crystallisation caused by metals coming out of solution at different points
Define metamorphic
A rock that has undergone transformation through heat or pressure
Explain how slate is formed
- formed from shale (sedimentary rock made from silt and mud)
- shale fractures easily
- recrystallises to from slate under heat and pressure
- slate is now impermeable and used for roofing
- slate is more valuable and splits easily into layers
Explain how Marble is formed
- Metamorphism (heat and pressure) of limestone = marble
- if subject to enough heat and pressure, all of its constituent parts will recrystallise
- marble is harder than limestone
- it’s rarer, impermeable and attractive
Define reserve
Natural resources that have been discovered and can be exploited profitably (with existing technology).
Valuable material that we can extract profitably.
Define stock
All the valuable material that we know exists (may not be able to get).
Explain the difference between a resource and a reserve
Resource is the amount of valuable material we can extract but unlike a reserve, it may not be profitable.
How might a reserve increase?
Material value goes up (easier to gain profit)