Lesson 15 — Activity 2:

The Extraction of Fossil Fuels



Explore

You know that fossil fuels form in the earth. In this activity, you will consider some of the ways in which fossil fuels are removed from the earth to be used for energy.   





Knowing what you do about the way coal, crude oil, and natural gas are formed, you can realize that geologists can find deposits of fossil fuels by looking for clues about the structure of the earth's composition in various places.

When coal was formed, it developed into flat layers. These layers occur as long seams or thick beds. In order to mine coal, miners look for these seams or beds. Coal near the earth's surface is strip-mined — layers of earth are removed until the coal is reached. Strip mining is a common form of coal mining in Alberta. Deposits found deep below the earth's surface are dug using networks of underground rooms and tunnels. Machinery then cuts into the coal, and conveyor belts lift it to the surface.

Open-pit mines devastate the landscape. Trees and soil are removed to retrieve coal. Coal companies that are environmentally conscious work to reclaim the land by covering the area with topsoil. They grade the area, then seed it with native plants such as grasses and trees.


The image shows reclaimed land from a mine in British Columbia.






This image shows a surface coal mine in Alberta.



Oil and natural gas deposits may be found when geologists look for areas in the earth's crust containing the porous rocks that assisted in the formation of the fossil fuels. Then, a well is drilled and the petroleum is pumped to the surface.


 In Alberta, drilling for crude oil began early in the 20th century. In 1914, a miner named W.S. Heron was on a farm near Turner Valley and saw oil seeping from the ground. He bought the land and the mining rights to the land and began drilling. This discovery of oil near Turner Valley, and later at Redwater, Leduc, and Woodbend, made Alberta into a major oil-producing area.



Natural gas is often found near petroleum deposits and will also be pumped into pipelines to travel to storage facilities.


Geologists (scientists who study all things related to the earth) use a number of different technologies to find the location of oil and natural gas.

 One common method is to use a seismic survey. During a seismic survey, shock waves from vibrator or thumper trucks, compressed air guns, or explosives are sent through the layers of the earth’s crust. The sound waves that return reflect off rock. These are detected by very sensitive equipment and are used to create images of the underground rock layers. Geologists study these images and other data looking for structures that may contain oil and natural gas.

 

Click on the + sign if you would like to look at this image more closely.




Once a likely place that contains oil and gas has been determined, oil companies begin drilling. When they hit reservoir rock with the rest of the oil or gas, the fuel may come to the surface on its own. As oil is taken from the reservoir, the pressure of the oil drops. Then a pump jack or a lift pump is installed to bring the oil to the surface.

Click on the Play button below to watch an animation of how a pump jack works.



After the crude oil is taken from the ground, it is refined into many different products. This is done by a process called distillation. Distilling allows materials with a low boiling point to be separated from those with a higher boiling point.

 When oil is refined, it goes into a distillation system. Here, heavy products such as kerosene and motor oil are separated from lighter liquids such as gasoline and naphtha.



In Alberta, coal is commonly used as fuel for power plants.

Oil is put to many uses. According to the U.S. Government's statistics on energy use, one barrel of oil would be used the following ways:

  • 47% for gasoline for vehicles
  • 23% for heating oil and diesel fuel
  • 18% for use in manufacturing a wide variety of products such as chemicals, synthetic rubber, and plastics, as well as ink, crayons, bubble gum, dish washing liquids, deodorant, eyeglasses, tires, and heart valves
  • 10% for jet fuel
  • 4% for propane
  • 3% for asphalt

Percentages equal more than 100 because of an approximately 5% processing gain from refining.

 

 

Natural gas also has a variety of uses. You are likely familiar with natural gas used for heating and cooking. However, it is also used in pulp and paper, metals, chemicals, petroleum refining, stone, clay and glass, plastics, and food processing industries as well as in some vehicles.

You can see that society has many uses for fossil fuels.



 Combustion


 Fossil fuels have energy stored in them. This energy is converted to thermal energy by a process called combustion (burning).  You learned in L7 — A1 that combustion is a chemical reaction that takes place when a substance combines with oxygen. With fossil fuels, combustion happens quickly. Thermal energy is released during the chemical reaction.

Here's an example: Propane is one gas that can be separated from natural gas. Combustion of propane provides thermal energy to heat houses, as well as cook foods in restaurants and on barbecues. Propane is also used to run some motor vehicles. 


 


   Like propane, all fossil fuels are made up of hydrogen and carbon and are known collectively as hydrocarbons.



Self-Check

Try This!

Try the questions below on your own first and then click on the tab to check your answers!

1. Strip mining is a common form of __________ mining in Alberta.

2. What do coal companies that are environmentally conscious do to reclaim the land?

3. How did W.S. Heron begin the oil drilling industry in Alberta?

4. What is one common method used to find the location of oil and natural gas?

5. How is crude oil refined?



1. coal

2. Coal companies that are environmentally conscious work to reclaim the land by covering the area with topsoil. They grade the area, then seed it with native plants such as grasses and trees.

3. W.S. Heron was on a farm near Turner Valley and saw oil seeping from the ground. He bought the land and the mining rights to the land and began drilling.

4. One common method that geologists use to find the location of oil and natural gas is a seismic survey.

5. Crude oil is refined by a process called distillation. Distilling allows materials with a low boiling point to be separated from those with a higher boiling point.




Images courtesy of www.imagesgoogle.com