Fracking, or ‘hydraulic fracturing’, is a process used to drill down deep into the earth to extract oil or gas for energy supplies.
The method includes injecting fluid down a well under pressure, creating cracks in the rock – this is where the word fracking comes from – the rocks are fractured, which then allows any oil or gas present to flow out to the wellhead and be recovered.
Since the early 1950s, the use of conventional hydraulic fracturing has been used, making small rock cracks around wellbores so a flow of oil or gas is created.
In more recent years, ‘high-volume hydraulic fracturing’ (HVHF) has been established, to extract gas from more much solid rock formations, like shale. An average shale gas well will use approximately 5 to 7 million gallons of fluid to complete a ‘frack job’. This fluid is a combination of water, sand and undisclosed chemicals to create fractures within the rock, on a horizontal drilling direction through the rock layer.
Fracking is only one example of extreme energy extraction. Other processes of unearthing energy from deep underground are also used. The relentless human demands for more and larger quantities of energy have resulted in other extreme measures of extraction in recent years: