Chapter 20

Question 1

Formation of petroleum

Answer 1

A source rock rich in organic material is deposited without being oxidized. The organic material experiences elevated temperatures when buried by overlying sedimentary rocks and allows oil and gas to be formed.

Question 2

Oil window

Answer 2

75 -150°C at a depth of 2–4 km.

Question 3

Gas window

Answer 3

+100°C at a depth of up to 3 km.

Question 4

Structural traps

Answer 4

Formed by folds and faults.

Question 5

Stratigraphic traps

Answer 5

Formed by the sequence of deposition that placed an impermeable cap rock above a porous reservoir layer.

Question 6

Movement of oil and gas

Answer 6

Low density of oil and gas causes them to move upwards. This can be blocked by an impermeable layer that overlies a porous reservoir causing the oil and gas accumulate in a trap.

Question 7

Where is Petroleum in Canada distributed?

Answer 7

Sedimentary basins formed in the Paleozoic and Mesozoic when sea levels were high. Trapped in overlying carbonates (reefs) and sandstones.

Question 8

Formation of coal

Answer 8

Fibrous and woody remains of land plants that accumulate in oxygen poor environments are cooked and compressed.

Question 9

Density of coal (3)

Answer 9

Density goes up with pressure/temperature in sequence:
1. Lignite
2. Bituminous coal
3. Anthracite

Question 10

Distribution of coal in Canada

Answer 10

Coastal environments around shallow seas where oil and gas formed. 98% in the Mesozoic (BC, AB, SK) and the Paleozoic (Maritimes)

Question 11

Oil sands

Answer 11

Mixture of sediment, water and bitumen, with oil that migrated upwards to the surface where the lighter components were lost.

Question 12

Oil shale

Answer 12

When the source rock is not subject to high temperatures and still contains kerogen. It is usually fine grained limestone that can be heated to crack the kerogen and form petroleum.

Question 13

Athabasca oil sands

Answer 13

50% of Canada’s oil production. Surface mining and underground extraction with steam assisted gravity drainage (SAGD).

Question 14

Coal Bed Methane

Answer 14

Gas trapped in coal seams that is extracted with water.

Question 15

Shale gas

Answer 15

Gas trapped in impermeable shale that is extracted with hydraulic fracturing and direction drilling.

Question 16

Methane hydrate

Answer 16

Solid mixture of methane and water that needs high pressure and low temperature to be stable. It is
found 200-500 m beneath seafloor on the continental shelf and formed by the reduction of carbon dioxide by bacteria.

Question 17

Primary pollutants

Answer 17

Pollutants emitted from identifiable sources

Question 18

Secondary pollutants

Answer 18

Pollutants formed from chemical reactions involving primary pollutants.

Question 19

Capacity factor

Answer 19

(energy generated)/(energy generated if operated all year) = ~0.5

Question 20

Electrical energy generated in Canada in 1 year

Answer 20

641.1 TWh = 2,308,000 TJ
Averaged over the year this is a power of 73 GW and an installed capacity of 145 GW.

Question 21

Hydroelectricity

Answer 21

60% of Canadian electricity. Large dams are efficient but eventually fill with sediment.
Pumped storage allows the grid to work with other sources. Installed capacity is ~80 GW, with BC Hydro at 12 GW.

Question 22

Geothermal advantages (4)

Answer 22

1. Low CO2 emissions
2. High capacity factor (24/7)
3. Small surface footprint
4. Scalable

Question 23

Geothermal disadvantages (5)

Answer 23

1. Location specific
2. Uncertainty of resource size from exploration
3. High initial costs
4. Needs water supply
5. Induces earthquakes

Question 24

Solar

Answer 24

Heat water directly or use
Photovoltaic (PV) panels to produce electricity.

Question 25

Tidal

Answer 25

Trapping seawater behind a dam at high tide and releasing it through hydroelectric turbines.

Question 26

Wind

Answer 26

2019 capacity was 13,413 MW, with wind farms in Canada ranging from 50 -350 MW. The average power is around 1 MW and 10 MW offshore.

Question 27

Nuclear

Answer 27

15% of Canada’s electricity generation due to significant uranium reserves (13.5 GW from 19 reactors in ON and NB). Not renewable but could bridge the gap as renewable energy resources are developed.