Hydraulic Fracturing Technology
The search for increased access to clean and natural gas has been fueled, in large part, by advancements in oil and gas technologies. Although hydraulic fracturing has been around since the 1940s, industry innovation has drastically improved the process, unlocking previously unattainable supplies of natural gas throughout the world.
In its abundant supply worldwide, shale is the most common type of rock found to hold fragments of organic material required to produce oil and gas. Since this material is locked in layers of rock, simply drilling through the formation is not enough to retrieve and release the liquid hydrocarbons. Instead, the rocks must be broken (or fractured) using highly-pressurized water.
Hydraulic fracturing is the process of pumping a specially formulated fracturing fluid through high-strength steel casing to deliver the force necessary to cause the reservoir rock to break, or fracture, facilitating the flow of oil and natural gas to the surface.
Fracturing fluid is an essential component of the shale gas extraction process. The fluid used is typically composed of 98% to 99.2% water and sand and less than 1% chemical additives.
To protect groundwater both during hydraulic fracturing and throughout the life of the well, up to eight layers of steel casing and cement are used to form a continuous barrier between the well and the surrounding formations. The steel casing and cement sheaths installed in the well are critical to containing the integrity of the well. Geologic conditions and state regulations, which oversee water location, quality and protection, dictate the number of barriers that are installed. In most cases, two to eight barriers are sealed in place to ensure safe well construction and drinking-water protection.