Hydraulic fracturing is a process used by drilling companies to increase the amount of oil and gas that is produced from each well. Fracturing is done after the well has been drilled into the formation. A fluid consisting of water, proppants (either sand or ceramic beads), and chemicals is injected into the well at extremely high pressures until eventually the rock, clay, compacted sand, or coal fractures. These fractures are then held open by the sand or ceramic, enabling the oil & gas to flow more freely out of the well. After the well has been fractured, the oil or gas is extracted from the formation. The process of hydraulic fracturing increases the exposed area of the producing formation, creating a high conductivity path that extends from the wellbore through a targeted hydrocarbon bearing formation for a significant distance, so that hydrocarbons and other fluids can flow more easily from the formation rock, into the fracture, and ultimately to the wellbore. Hydraulic fracturing treatments are designed by specialists and utilize state-of-the-art software programs and are an integral part of the design and construction of the well. Pretreatment quality control and testing is carried out in order to ensure a high-quality outcome.
In order to carry out hydraulic fracturing operations, a fluid is pumped into the well’s production casing at high pressure. It is necessary that production casing has been installed and cemented and that it is capable of withstanding the pressure that it will be subjected to during hydraulic fracture operations. In some cases, the production casing will never be exposed to high pressure except during hydraulic fracturing. In these cases, a high- pressure “frac string” may be used to pump the fluids into the well to isolate the production casing from the high treatment pressure. Once the hydraulic fracturing operations are complete, the frac string is removed.