Lithosphere Flashcards
How do hydrothermal processes produce economically viable metal ore deposits
- hot mineral solutions flow along veins away from the batholith
- minerals have different solubilities (different concentrations)
- minerals cool in the solution further from the batholith and crystallise fractionally (creating seams of the deposit)
Why would a reduction in the market price change a mineral’s cut off grade
Less money would be available for extracting and processing the ores so the COOG increases so that its the most profitable for extraction
Why would extra energy be needed if there grade decreases
- there will be a larger overburden to remove (deeper mining)
- more ore would have to be mined (labour, equipment and transport costs)
- less efficient extraction (more waste produced)
What are the methods to locate deposits
- trial drilling (presence, location and concentration)
- remote satellite sensing
- magnetometry
- gravimetry (Shae and density)
- seismic surveys (shape, depth and desity)
What is the new technology used for lower grade ore extraction
- bioleeching
- phytomining
- iron displacement
- leachate collection
- polymer adsorption
How does bioleeching and phytomining reduce environmental impacts of mining
- less energy intensive than traditional mining
- less global warming and acid rain from waste pollution
- uses bacterial population
- decontaminates the polluted ground
How does iron displacement reduce the impacts of mining
Reuses scrap metal (less waste produced)
How does leachate collection reduce the environmental impacts of mining
- makes use of waste material
- reduces leachate drainage problems (polluting rivers and corroding land)
How does polymer adsorption reduce the environmental impacts of mining
- reuses waste
- less equipment needed (less emissions)
Why is a logarithmic sequence used instead of a liner one
Shows the exponential relationship of the lasky principle (a large set of values)
Why wouldn’t a mineral deposit be exploited
- unstable overburden could collapse
- deep overburden would produce a lot of waste (costly equipment and hazardous to health)
- a thin layer of ore wouldn’t be economically viable
- land use conflict (legal protection of the land or private property) inhibits access to mine
- price of the equipment and work force
What pollutants does polymer adsorption control
- heavy metals
- oil
- radioactive material
What pollutants does biomedication control
- asbestos
- heavy materials
- oil
- pesticides
What pollutant does leachate collection control
Heavy metals
What pollutants does phytoremidiation control
- heavy metals
- oil
- pesticides
What pollutants does satellite monitoring control
- oil
- radioactive waste
How does a seismic survey work
It uses reflected sound waves to produce data on the density, depth and shape of the rock strata
How does resistivity work
It measures the difficulty or ease with which electric charge passes through a rock
How does gravimetry work
It measures and maps out variations in rock density
How does technology advances and increased access to low ore grades affect the economic viability
The quantity of metal extracted will increase as it would be more cost effective eg phytomining, bioleeching or iron displacement
How does an increases in the market price of the purified metal affect the economic viability
Quantity of extraction will increase as companies justify lower quality ores because it would still be profitable
How does the increase of a cut off grade affect the economic viability
Only higher ores would be extracted as profit margins narrow
