Minerals Extracted From The Lithosphere Flashcards
What is the litosphere?
The uppermost layer of the mantle and the crust that exists above it it along with the seidments/soils that are sat over it
What can be found in the litosphere?
Minerals and metals which are used by humans for many things
What does non-renewable mean
Mewns that something in this case minerals will run out
Why are minerals non-renewable
They reform too slowy within the earth
The timescale are longer than that of humans.
What are the 3 outcomes for minreals?
- We run out and find alternatives
- We find new sources by using new tech
- We recycle what we can
What are the three types of mineral resource
- Metal and metal ore
- Industrial minerals
- Construction materials
What are industrial minerals?
Sands and gravels
What are construction materials
Limestone and gypsum
What is an igenous intrusion?
When magma cools and solidifies undergroud without breaching earths surface.
What does an igneous intrusion provide
The heat source needed to form a deposit
How does a deposit form by igneous intrusion
Hot fluids from volatiles (rock in magma) or by fluid in surrounding rock dissolve chemical elements.
Fluids cools and drop the sediments crystallising and forming ore veins
What is an ore?
A rock which contains concentrations of minerals of a particular type within it
What are concentrated strands of mineral called?
Veins
What are metamorphic processes?
Tectonic processes cause huge slabs of crust to move and collide
Do not always completely melt the crust
What do collsions of tectonic slabs cause?
Increase in heat and pressure
What happens if the rocks do not reach their melting point?
The rocks become changed but not melted
From sedimentary grain to strong crystallised rocks
What are examples of metamorphic processes?
Limestone turns into marble
Mudstone under pressure becomes slate
Why was the sky and water pink/orange on early Earth
As there was little free oxygen
Proterozoic rocks exposed at the surface had a high level of iron that was released by weathring
What happened at the surface when iron was weathered?
As there was no oxygen iron entered the ocean as the iron ions
What is the name for the primitive phostosynthetic organism?
Blue-green algae
What does blue-green algae produce? (waste)
O2 as a waste from photosynthesis
What did free oxygen form when combined with iron?
Magnetite - iron oxide
What did the iron ion form in the sea floor?
Bands of iron rich sediment
What happened to iron when the biomass expanded
Iron was abke to neutralise all waste O2 this meant O2 rose to toxic levels in the sea water
What happened to the algae when the O2 concentration increased?
Resulted in extinction as it was poisonous to them created an iron poor layer of silica
What allowed more iron rich layers to form?
The reestablishment of the algae populations
What happened as algae populations rose and decline over time?
The process of toxic O2 then reestablisent would repeat creating bands of rich and poor iron layers
What are sedimentary processes
Cause minerals to settle and build up
What is the build or sedimentary mineral
Placer deposit
Ehat is an example of a placer deposit
Gold at the bottom of a water fall or thr near shallow bank of a river
What are examples of alluvial deposits
Sands, gravels and clay
How are alluvial deposits sorted
Sprted by water the material with less mass carried further
Why is water velocity important fir alluvial deposits?
Heps sorting as to move larger materials like gravels the water needs more energy
What is aggregate?
“Bulk materials” - coarse to medium grained sedimentary material used in construction
Most mined materials
Where does aggregate tend to collect?
Rivers
River terraces
Glacial and fluvioglacial areas
Beaches
What is an evapourite?
The natural salt or minerla left after the evapouration of a body of water
What is an example of a evaporite?
Halite (rock salt)
What are biological sediments
Sediments formed from once living organisms
What are the three main biologiclal sediments?
Coal
Oil
Limestone or chalk
How does coal form?
Formed over millions of years from vegetation in swamps
How does oil form?
Made over the millions of years from the death of millions of tiny organisms in seas
How does limestone/chalk form?
Formed from the shells if dead marine creatures slowly crushed and compacted over time to form rock
What are placer deposits?
mineral deposit in which grains of a valuable mineral like gold or the rare earths are mixed with sand deposited by a river or glacier
