2.3+3.2 conventional and unconventional coal, crude oil and gas

• Aardrijkskunde
• Middelbare school
• vwo
• Leerjaar 3,4

§2.3 Delfstoffen in soorten en maten 

§2.3 World: Mineral resources

2.3+3.2 conventional fossil fuels

and unconventional coal, crude oil and gas

Get ready to take notes

At the end of this lesson..

.. you understand the difference in formation between ores and fossil fuels

..you understand the difference between conventional and unconventional fossil fuel sources

..you can use terms like parent/source rock, reservoir rock and impermeable layer to explain how fossil fuels are stored in the earth

At the end of this lesson..

.. you understand the difference in formation between ores and fossil fuels

..you understand the difference between conventional and unconventional fossil fuel sources

..you can use terms like mother/source rock, reservoir rock and impermeable layer to explain how fossil fuels are stored in the earth

Which mineral resource might be formed here?

Gold ore

Iron ore

2.3 What are ores?

Minerals in which we find metal and from which we can extract a mineral resource.

So ....all ores are minerals, but not all minerals are ores .

Examples of ores are:

• iron ore
• cupper ore
• silver ore
• gold ore

Climate  →  tropical 

Carboniferous: 350-290 million ya

position →  around equator

→ Tropical swamp

Explain coalification to your neighbour

Plants → peat → lignite → coal

                                                                                                   3 phases:

2

2. Due to further sedimentation, the peat is burried deeper and deeper. The deeper the layers, the higher the temperature. This leads to the transformation of peat into brown coal (lignite).

3

3. With further pressure and higher temperatures deeper in the crust, the lignite (brown coal) transforms into coal. These three phases together are the coalification proces. 

1

1. Dead plant material is covered by water in a swamp. Due to a lack of oxygen, the plants do not decompose (rot). When layers are stacked, peat is formed.

Take note!

Crude oil forms from plankton in the oil window - temperature between 60 and 120 º C

  Dead plankton floats to the bottom of the sea

Plankton in warm shallow seas  

Thick layers of sediment on top of the plankton

Temperature and pressure increase in the plankton layer

Formation oil in Mesozoic

- dead plankton bottom sea

- covered by layers like sand

- high temperature and pressure turned it into crude oil

Together gas was formed

Formation crude oil

Take note!

When was the basis for crude oil formed?

1. Jurassic
2. Carboniferous
3. Precambrian
4. Holocene

When was the basis for coal formed?

1. Jurassic
2. Carboniferous
3. Precambrian
4. Holocene

Coal

Crude oil

gas

plankton

peat

warm sea

tropical swamp

carbon

triassic jurassic cretaceous

folds & fractures though plate tectonics

Open pit mining

offshore

Traditional/conventional resources

Fossil fuels -->  exhaustible energy sources 

Conventional oil and gas

'Easy' to extract

Conventional -> "usual"
"normal"

oil & gas from reservoir rock

Take note!

conventional reserves

50 years? 100 years?

unconventional reserves

more effort, money and energy 

What is the difference between conventional gas extraction and fracking for shale gas?

Shalegas, is not stuck in porous rock like sandstone (reservoir rock) by an impermeable layer like rock salt, but is trapped between layers of shale/slate                                                     (source rock)

Water, sand and chemicals break this rock and keep the new cracks open so gas can travel out

01:49

What is an important feature of the impermeable layer?

1. Few pores
2. Very porous

05:50

What are the risks of fracking?

Explain: what is the difference between conventional & unconventional fossil fuels?

Unconventional resources

Still fossil fuels

Harder to extract

Unconventional -> "unusual"
"not normal"

oil & gas from mother rock (shale gas) or mixed in with sediments (tar sand)

Take note!

Drawbacks of tarsand extraction+fracking

Landscape & surface is harmed

Costs water and energy to extract (even more  than conventional)

Contaminates soil & ground water

Earthquakes

Gas escapes when extracted -> direct green house gasses

01:49

Gas in reservoirrock

Gas in parent rock

unconventional gas extraction

01:19

What is tar sand?

1. Bitumen, which are blobs with oil around it
2. A sand & water mixture that contains crude oil
3. A mixture of sand, clay, water and bitumen
4. Sticky clay which you can get oil from

04:35

Why is extracting crude oil from the bitumen in tar sands more expensive than from a conventional oil field?

07:03

Name the three ways extraction of tar sands harm the natural environment

07:44

Give an argument why it is okay for the Canadian government to continue extracting crude oil in this way.

Exercises to complete (HW)

See planner:

2.3- 1-5 (they are rather quick)

3.2 4+5 (they might require more thinking)