It has long been known that shales contain oil and gas but it is only within the last decade that the development of two technologies has made the extraction of gas from shale an economic proposition:
•The first of these is the ability to drill horizontally from an initial deep vertical bore.
•The second is the development of a process called ‘hydraulic fracturing’ .
Hydraulic fracturing is the use of a fluid made up of around 90% water carrying a load of sands, chemicals and sometimes diesel oil and forcing it into shales under high pressure, causing them to fracture and release the gas they contain.
This is the process from whose name the brute industrial tag of ‘fracking’ has been hacked.