Week 12: Energy & Mineral Resources

Question 1

What are Mineral Resources?

Answer 1

Concentration of material of economic interest in or on the earth’s crust

(emphasis on concentration)

Question 2

What are Ore Reserves?

Answer 2

Parts of a Mineral Resource that can at present be economically mined

Question 3

What are Fossil Fuels?

Answer 3

Any organically derived sedimentary rock, or a product from an organic sedimentary rock that can be burned for fuel

(e.g. petroleum, natural gas, coal)

Question 4

Which country has the largest coal reserve?

Answer 4

The US

Question 5

How much of global electricity does coal produce?

Answer 5

1/3

Question 6

What are the two stages of fossil fuel formation?

Answer 6

1) Decay of organic matter by biochemical alteration near the surface

2) Dewatering of sedimentary material and CRACKING of the organic material due to burial and increase in pressure and temperature

Question 7

What is Cracking of organic material?

Answer 7

Large complex hydrocarbon molecules are broken down into smaller molecules (like methane)

Question 8

Coal is derived from what material?

Answer 8

terrestrial plant material

(e.g. peat bogs, mangrove swamps)

Question 9

What happens to coal with increase of temperature and pressure?

Answer 9

Becomes anthracite (low grade metamorphic) - burns better

Question 10

How does Peat become coal?

Answer 10

Major chemcial and physical changes due to increase in Pressure and Temperature

Question 11

What did Anita Harris do?

Answer 11

She found a correlation between the colour of conondonts and grade of the coal, and how that determined the temperature of the coal

Question 12

What are the three grades of coal that form?

Answer 12

Lignite

Bituminous coal

Anthracite coal

Question 13

What do Petroleum and Natural Gas form from?

Answer 13

Marine organisms such as phyto plankton and bacteria

Question 14

What kind of hydrocarbons is Petroleum made of?

Answer 14

Naturally occurring liquid hydrocarbons

Question 15

What kind of hydrocarbons is Natural Gas made of?

Answer 15

Naturally occurring gaseous hydrocarbons

Question 16

What are the 4 steps in the formation of Petroleum and Natural Gas?

Answer 16

1) Formation of the source rock
2) Formation of hydrocarbon molecules
3) Migration of the hydrocarbon molecules away from the source rock
4) Trapping of the molecules in a suitable reservoir rock

Question 17

What are some active sedimentary basins for Petroleum and Natural Gas?

Answer 17

• Gulf of Mexico
• Mediterranean

-Black Sea

Question 18

How do hydrocarbons move away from the source rock?

Answer 18

Because they’re lighter than water and will therefore rise up through porous rock

Question 19

Describe a good reservoir rock?

Answer 19

Permeable so that its fluids can be removed from them

Question 20

What is a trap?

Answer 20

A zone that confines the migration of hydrocarbons

Question 21

What are stratigraphic traps?

Answer 21

Poruous and permeable rocks being sealed off by an overlying impermeable bed.

Spreads out laterally with regional seal and eventually can surface (Alberta oilsands)

Question 22

What are Structural Traps?

Answer 22

Anticlinal domes, flanks of a salt dome, normal and thrust faults

-> oil and gas are trapped by these formations

Question 23

What is a Mineral Deposit?

Answer 23

A naturally occurring anomalous concentration of minerals that may be extracted at a profit. (don’t have to be)

Question 24

What is an Ore Deposit?

Answer 24

A naturally occurring anomalous concentration of minerals in amounts sufficient to permit economic and profitable recovery

Question 25

List examples of precious and base metal deposits

Answer 25

gold, silver, platinum, copper

Question 26

List examples of ferrous metal deposits

Answer 26

iron, nickel, molybdenum

Question 27

List examples of mineral fuels

Answer 27

coal, uranium

Question 28

What does Concentration mean (in terms of Mineral Resources)?

Answer 28

Concentration = mass of element (mineral) / mass of rock body containing it

Question 29

What is the Economic concentration (grade factor)

Answer 29

concentration that is required for any
element/mineral to be economically mined

Question 30

What is the Economic Concentration factor

Answer 30

grade factor divided by the average
concentrations of the element in continental crust

Question 31

How do elements or minerals become concentrated above
average crustal concentrations?

Answer 31

• Hydrothermal processes
• Magmatic processes
• Sedimentary processes
• Weathering processes
• Metamorphic processes

Question 32

What are hydrothermal deposits?

Answer 32

Minerals from magmatic intrustion are surrounded by hot water which ascends through fractures in the rock (forming veins).

Precipitation due to:

1) change in pressure
2) change in temperature
3) change in the fluid composition

Question 33

What are Veins?

Answer 33

Fractures that are partially or completely filled with
minerals that precipitated out of solutions.

Fluids move from high pressure to low
pressure conditions (pressure gradient)

Question 34

What are Black Smokers?

Answer 34

Cold water from ocean penetrates down, gets heated in convective layer, hot fluids then rise before hitting the cold water in the ocean, and the metals drop out. Over time this forms chimneys of minerals

Question 35

What are Porphyry Deposits?

Answer 35

Deposits forming from continual cycles of presure forming and thereby many generations of mineralization forming upwards towards the surface

Question 36

What is Supergene enrichment

Answer 36

• Elements leached out of surface zone
• Concentrates at water table
• Can raise ore to minable concentrations

Question 37

Describe Magmatic Ore Deposits

Answer 37

• Due to segregations (separation) of minerals in mafic or ultramafic intrusion
• Settle because of high density and low magma viscosity

Question 38

What are Placer Deposits?

Answer 38

• Deposition of high density, resistant minerals in unconsolidated sand and gravel (e.g. gold)