Lthosphere Flashcards
How does the igneous process create mineral deposits?
creating rocks by the cooling and hardening of magma.
How does hydrothermal deposition create mineral deposits?
igneous intrusions rocks are formed from the heating/cooling of magma
Pressurised superheated water moves away from the batholith and cools forming crystals
How does the metamorphic process create mineral deposits?
igneous processes and tectonic movements can alter existing rocks without a high temp./pressure produces metamorphic rocks
How does the sedimentary process create mineral deposits?
causes minerals to settle and build up layers of deposited sediments
How do proterozoic marine sediments form?
form when dissolved iron compounds become oxidised by o2 from photosynthesis producing insoluable iron oxide deposits
How are alluvial deposits formed
materials are carried and separated by flowing water and different densities minerals can be carried in different velocities of water
How are evaporites formed?
Isolated seas then crystals can be formed as the water evaporates
What is Lasky’s principle
In general, as the purity of the mineral decrease, the amount of mineral present increases exponentially
What is the stock
All minerals in the lithosphere
What is the resource
contains all exploitable materials including future exploitable materials
What is the reserve
contains all materials that can be exploited now
How does ir spectroscopy detect rocks
different minerals emit infrared radiation at different wavelengths and these can be used to identify them
How does gravimetry detect rocks
gravimeters detect variations in gravity caused by variation in density and mass
How does magnetometry detect rocks
magnetometers detect rocks that are more magnetic
How do seismic surveys detect rocks?
sound waves are produced by controlled explosions/ seismic vibrator. The echoes can give information about the depth, density and shape of rock strata
What is resistivity
is the measurement of the difficulty with which electricity passes through a material
What is trial drilling
taking samples of the rocks underground
What is chemical analysis
using lab tests to confirm the chemical composition and purity of the minerals in the rock samples
If the market value is high the COOG…
decreases
If the market value is low the COOG…
increases
If technology improves the COOG…
decreases
If there is a high energy cost the COOG…
increases
What is the loss of amenity?
mining causes aesthetic problems for local communities but mines can be restored when no longer used
What causes dust and how can it be limited
blasting and vehicle movement cause dust and water sprays limit dust
How can noise be reduced?
carrying out blasting at certain times and using embankments to absorb the noise
What effect can turbid drainage water have?
limit light in water for photosynthesis
What is bioleaching?
using bacteria to extract minerals
What is phytomining?
allowing plants to absorb minerals then burning them
What is iron displacement?
using iron to displace copper in a solution
What is leachate collection?
percolating water through spoil heaps to dissolve metal iron and leachate
What is polymer absorption?
metal ions dissolved in seawater will absorb into some synthetic and natural polymers
what are polymetallic nodules?
metal-rich nodules found underwater which contains about 30% manganese and extraction requires an international agreement and is expensive
What are the environmental impacts of extracting polymetallic nodules
disturb and kill the seabed, increase the turbidity of nodules, and re-deposition is likely to kill filter feeders
What are the 2 types of waste?
post and pre-consumer waste
What are biological sediments?
process where living organisms can form mineral deposits.
What factors affect mining viability?
Ore purity Chemical form Overburden and hydrology Depth Economic viability Transport Costs Market Economics
What are the environmental impacts of mineral exploitation?
Land take Habitat loss Loss of amenity Dust Noise Turbid drainage water Spoil disposal
What are 2 improvements in exploratory techniques?
Better remote sensing
Portable field equipment
What does deep mining allow?
Mining underground where it may be too hot or dangerous
What does open-cast mining allow?
Minerals to be extracted quickly and cost-effectively
