Hydraulic fracturing is best defined as a stimulation process that is used in order to fully utilize the use of underground resources including oil, natural gas, geothermal energy and water. This method is used to enhance the flow of underground fractures to allow oil or natural gas to move more freely from rock pores to wells that bring up the resources to the surface. The whole process starts with having to build the proper and needed infrastructure which also includes the well construction. These Production wells are drilled in the vertical direction only, but can be paired with horizontal or directional sections. Vertical wells can be drilled hundreds or thousands of feet under the surface.
The fluids made of water and chemical additives are then pumped into a geologic formation at high pressure during hydraulic fracturing. When the pressure of the fluid surpasses the rock, the fluid opens the fractures and extends hundreds of feet away from the well. Once this is done, a propping agent is pumped in the fractures to keep them from closing back up when the pressure is let go. After the fracturing is done, the pressure of the geologic formation causes the injected fluids to rise to the top where it is saved in tanks or pits before disposal or recycling. Any recovered fracturing fluids are called “flowbacks” and is then disposed of into surface water or through underground injection.
Currently in the states, hydraulic fracturing has already made it’s home in places such as Ohio, New York, Pennsylvania and West Virginia with more being targeted for the future. In Europe, World Shale Gas Resources are starting to duplicate what was done with hydraulic fracturing in the states. However, it is said that it may not work in different countries only because the rock formations are different depending on the region. Even in the states each of the gas shale basins are different and have a unique set of exploration criteria and challenges. Despite
References: Hydraulic Fracturing Background Information http://water.epa.gov/type/groundwater/uic/class2/hydraulicfracturing/wells_hydrowhat.cfm Shale Gas in Europe: Revolution or Evolution http://www.ey.com/Publication/vwLUAssets/Shale-gas-in-Europe_revolution-or-evolution/$FILE/Shale-gas-in-Europe_revolution-or-evolution.pdf