Types of mining
A) The two types of mining and their differences
One type of mining is surface mining the second one is subsurface mining. Surface mining is used where the material to be extracted is located close to the surface. The overlying ground cover is removed, the material is mined, and the ground cover is replaced. Subsurface mining is used where the material is in veins deep under the surface, or lock by rock layers in a way that make surface access easier. The first miners used existing caves, but technology has helped drilling increasingly deeper and more complex to reach veins of coal and metal ores .
surface mining
- its Safer and easier than subsurface mining.
- Does more damage to the surface ecosystems than subsurface
- Creates more of a mess than subsurface
Subsurface Mining
- Not much widespread damage to ecosystems
- Difficult and expensive to dig
- Very dangerous conditions can include collapses, released gases, particulates in the air, low oxygen, and heat
comparison of land drilling vs. ocean drilling
Onshore drilling : drilling deep holes under the earth surface to extract natural resources like oil and gas . offshore drilling relates to drilling underneath the sea bed. They both drill deep down.
production challenges
land and ocean drilling use exploratory equipment like oil separators, pipelines and pumps.
environmental concerns
the farther the drilling goes the higher the cost would be for the enegergy resources.
What is fracking?
Fracking is the process of drilling down into the earth.
how it os done?
Water, sand and chemicals are injected into the rock at high pressure that allows the gas to flow out to the well.The process can be vertically or the common way ,by drilling horizontally to the rock layer and that can create new pathways to release gas or can be used to extend existing channels.
sources
1) http://www.answers.com/Q/What_is_the_difference_between_surface_and_subsurface_mining
2) http://blogs.up.ac.za/weblog/media/file/estelle/adobe%20files/ch2.pdf
3)http://www.mine-engineer.com/mining/open_pit.htm
4)http://www.bbc.com/news/uk-14432401
5) http://www.entranceconsulting.com/2013/10/23/onshore-versus-offshore-drilling/
strip mining
1) strip mining: elimination of soil and rock above a layer, followed by the removal of the exposed mineral.
terrace mining
When overweight is too thick.
open-pit mining
excavate or cut in the surface of the earth for the purpose of extracting the ore and is open to the surface