‘Unconventional’ Oil & Gas Production
Hydraulic fracturing (also known as ‘fracking’) is the process of pumping a water-based solution down into the ground to fracture the rock within the earth. Fracturing the rock beneath the earth releases valuable compounds that are held within those rocks, such as crude oil and natural gas.
Wells are drilled vertically hundreds to thousands of feet below the earth’s surface, they can then be extended by drilling thousands of feet further horizontally. Once the wells have been drilled, a solution made up of water, proppants such as sand or man-made ceramic materials, and other chemicals are pumped down the wells at a high pressure to blast and fracture the rock below. Proppants are small solid materials such as sand or ceramics that are added to the water-based solution in order to keep induced fractures open after the pressure blasting has finished.
Once the fracturing process has been completed, the solution rises back to the surface along with any other compounds released from the fracturing process due to the internal pressure of the rock beneath the earth. This solution is known as the ‘flowback’, it is then collected and stored so that it can be treated, and the useful Oil and Natural Gas can be separated. The solution is often then recycled and used again for more fracturing.
Hydraulic fracturing is a form of ‘unconventional’ oil and gas production. Until recently, unconventional wells were not economically viable to produce from, since the oil and gas are highly dispersed within the rock instead of being concentrated in one underground location. However, the technological advancements in extraction practices such as hydraulic fracturing have made these wells profitable to produce from, vastly increasing the global supply.