Above and Below
Mining, Drilling, and Fracking
Mining
Surface Mining
Surface mining is the most common type of mining. Surface Mining involves removing layers of dirt and rock from the surface to reach mineral deposits. It is used when minerals or natural resources are found near the surface. Different methods of surface mining are employed to dig out minerals.
Sub-surface Mining
Sub-surface or underground mining is the second type of mining. Sub-surface mining is used when the minerals are found extremely low under the surface. Underground mining has 2 different categories; Hard Rock, and Soft Rock. Hard Rock mining is used for hard minerals such as gold, copper, lead, or diamonds. Soft Rock mining is used for softer minerals like coal. Both have different methods to extract minerals.
Surface Mining
Strip Mining
Strip mining is removing a layer of soil and rocks layer by layer until you get to the mineral underneath. Typically used for coal. It is not very practical to use.
Environmental Effects
- It is extremely destructive
- It can leave permanent scars on the earth. (destroys landscapes, destroy habitats)
- Run-off of dirt, and chemicals can hurt water ecosystems nearby.
- Chemical and groundwater contamination.
- Dust pollution.
Open-pit Mining
Open-pit mining is extracting minerals from an opening in the ground. (Strip mining and Open-pit mining are extremely similar but still different)
Environmental Effects
- Destructive
- Destroys habitats
- Run-Off
- Pollution
Mountaintop Removal
Mountaintop removal is almost exactly as it sounds. It is a mass restructuring of the earths surface. It is used to mine coal that is found on top of mountains, and usually leaves behind a flat surface.
Environmental Effects
- It destroys the terrain.
- Run-off is a huge problem with mountaintop removal.
- General pollution is also a problem.
Sub-surface Mining (Hard Rock)
Cut and Fill Mining
A ramp is cut to to the bottom of the mineral and dug out until the mineral vein is exhausted. It is then refilled to the top of the ramp.
Environmental Effects
- lowers water table
- Huge amounts of waste earth are brought to the surface
- subsidence
Room and Pillar Mining
Used for ores found in a flat or straight area. Rooms are mined and pillars are placed to support the ceiling of the room and the process is repeated until everything is mined.
Environmental Effects
- Safer and more ecologically safer than most types.
- Although more safer it still can cause some effects such as pollution and subsidence if it is not properly done.
Sub-surface Mining (Soft Rock)
Longwall Mining
A large hallway is cut into the rock and machines are used to cut into the walls of the hallway and extract coal.
Environmental Effects
- Subsidence is a major problem with Longwall mining.
- It can damage tree roots and cause erosion
- lead to foundation problems
Blast Mining
Uses dynamite to remove coal veins. Explosives are loaded onto carts and pushed to the digging area and exploded.
Environmental Effects
- Erosion/Run-off
- Damage terrain
- Subsidence
- Pollution
Drilling
Land Drilling
Drilling Rig used to drill and extract oil, and natural gas. Offshore drilling is more commonly used because of how much more oil can be found on the shore. Started in the 1900's. The older machines are being replaced frequently because new technology is coming out.
Environmental Effects
- Displaces ground
- Pollution
Ocean Drilling
Drilling rig placed in the ocean to drill underneath the seabed to extract petroleum. More popular than land drilling. It started in the early 1900's. It was a hard and long process to create the machines in the beginning. It is also a huge risk when constructing the machine.
Environmental Effects
- Oil Spills
- Harmful to ecosystem that live around the machine
- Pollution
Fracking
Fracking is the process of drilling into a high pressure area of rock and water to release natural gas and oil. Chemicals, water and sand are introduced into the ground to induce a reaction.
Environmental Effects
- The amount of chemicals used can be a risk to the environment.
- A lot of water is used for fracking.
- Can be dangerous for the area around.
- The safety of fracking is still being questioned.
Bibliography
http://www.greatmining.com/Surface-Mining.html
http://www.greatmining.com/Softrock-mining.html
http://www.greatmining.com/Hardrock-mining.html
http://www.australianmining.com.au/news/study-measures-the-environmental-impacts-of-longwa
http://www.greenpeace.org/international/en/campaigns/climate-change/coal/Mining-impacts/
http://oceanservice.noaa.gov/facts/oilimpacts.html
http://www.bbc.com/news/uk-14432401
http://www.nabors.com/services/drilling-rig-services-overview/land-drilling