Exam 3 Flashcards
Which of the following is a non-metallic mineral?
a. Gypsum
b. Gold
c. Copper
d. Zinc
e. Aluminium
Gypsum
The process of separating a metal from its host rock is called what?
Smelting
The material produced when two metals are mixed together is called what?
An alloy
Gold is found primarily near kimberlite tubes.
False
Which type of coal is most abundant?
Bituminous
Which of the following choices is not one of the fundamental (permanent) sources of energy?
a. Fossil Fuels
b. Pull of gravity
c. Heat from the Earth’s interior
d. Fusion in the Sun
e. Radioactive Decay
Fossil Fuels
Which of the following nations gets the majority of its electricity from hydroelectric generation? Select one: a. Norway b. France c. Germany d. United States e. China
Norway
If the wind blowing through a turbine doubles in speed, how much additional energy is produced?
8x (x^3)
Which nation relies most on geothermal energy?
Iceland
Which of the following changes on Earth is cyclical? Select one: a. Differentiation b. Cooling of the mantle c. Building of supercontinents d. Evolution
Building of supercontinents
Which of the following investigative techniques would tell you most about climate 60,000 years ago?
a. Ice cores
b. rock cores
c. Dendrochronology
Ice cores
What is our current atmospheric CO2 concentration?
405 ppm
Categories of rocks and minerals
Metallic and nonmetalic
Metallic
Gold Silver Copper Lead Zinc Iron Aluminum
Non-metallic
Sand and gravel
Gypsum
Halite
Dimension stone
Types of metals mined
Precious – Rare and economically important.
Gold (Au)
Silver (Ag)
Platinum (Pt)
Base – Commonly used in industry. Iron (Fe) Lead (Pb) Zinc (Zn) Tin (Sn)
NC Gem Stones
Aquamarine, beryl, citrine, emerald, garnet, moonstone, rose quartz, ruby, sapphire, tourmaline, staurolite, topaz, and many varieties of quartz
Ores
Rock with a concentration of metal-rich minerals; present in enough abundance to be economic to mine. Metal must be readily extracted from the material
Alloys
Blending metals makes an alloys, like stainless steel or bronze.
Properties are usually superior to a standard metal
How do ores form?
Magmatic and hydrothermal activity. Ore and silicate minerals are deposited by hot magmatic fluids in cracks in surrounding rocks
Secondary Enrichment
An especially important class of residual deposit is formed by both the removal of valueless material in solution and the solution and redeposition of valuable ore minerals. Because solution and redeposition can produce highly enriched deposits, the process is known as a secondary enrichment.
Hydraulic Sorting
In high-velocity water…
Low-density minerals are suspended and washed away.
High-density grains are concentrated by settling out.
Diamonds
Diamonds originate under extremely high pressure.
~ 150 km deep – in the upper mantle.
Pure carbon is compressed into the diamond structure.
Rifting causes deep mantle rock to move upward.
Diamonds are found in kimberlite pipes.
Coal Characteristics
Black, brittle, carbonaceous sedimentary rock.
Remains of organic matter from vegetation.
Important global energy source; CO2 emitter.
Only found in rocks younger than 420 Ma.
Coal formation
Coal-forming eras. Carboniferous (354 – 286 Ma). Warm climate. Broad epicontinental seas. Tropical deltaic wetlands. Cretaceous (144 – 65 Ma).
Vegetation accumulates in an O2-free setting.
Absence of oxygen prevents organic matter decay.
Marine deltas.
Tropical coastal wetlands.
Sea level rise and fall buries wetland deposits.
Coal formation requires heat and pressure.
Compaction and decay turns plant debris into peat.
Approximately 50% carbon.
Readily cut out of a wetland deposit.
Coal Rank
Classification based on the carbon content.
Peat 50% C
Lignite 70% C
Bituminous 85% C
Anthracite 95% C
Anthracite forms by metamorphism in an orogenic belt.
Higher-rank coal yields more energy when burned.
Tunnel Mining
Underground mines – Ore obtained by tunneling.
Tunnels are linked to a vertical shaft.
Ore is removed by drilling and blasting.
Excavated ore is hauled to the surface for processing.
Expensive and dangerous.
Coal Mining
Underground mining – Coal removed by tunneling.
For coal deeper than 100 m, shafts are advanced to seam.
Tunnels excavated along the seam remove the coal.
Coal mining is specialized, expensive, and dangerous.
Tunnels can collapse.
Methane gas.
Asphyxiation.
Explosions.
Black lung disease.