Hydraulic fracturing refers to the process of creating fractures in rocks and rock formations by injecting fluid into cracks to force them further apart. The larger fissures allow more oil and gas to flow out of the formation and into the wellbore, from where it can be extracted.
Hydraulic fracturing employs a fluid which typically consists of 99.5% of water and sand.
The remaining 0.5% of the fluid is composed of between two and four additives, which are generally used to reduce pumping friction, add viscosity and to make it easier for gas and oil to return to the wellbore. More detailed information regarding the purpose and use of various additives is provided at www.fracfocus.ca
Digging Deeper: Get the Facts on Hydraulic Fracturing
Source: Canadian Association of Petroleum Producers
After the hydraulic fracturing fluid has been pumped under high pressure into the formation to create cracks, the sand in the mixture then holds those cracks open. This allows natural gas to flow through the grains of sand out of the rock, into the well bore and up to the wellhead, where it can be treated before being transported to markets.
Once the fracturing operation is finished, the well is considered “completed” and is ready to produce oil and/or natural gas for years and even decades, to come. Hydraulic fracturing has resulted in many oil and gas wells attaining a state of economic viability, due to the level of extraction that can be reached.
Source: Canadian Association of Petroleum Producers, PDF file