As home to supermajors, as well as a plethora of smaller, independent energy players, the US boasts one of the largest concentrations of energy personnel in the world. With its insatiable appetite for energy resources, the United States is the world's single largest consumer of oil, using as much as 20.73 million barrels per day as of 2008. Recently, interest has peaked in the vast quantity of untapped natural gas resources in the US, the reserves of which were inventoried in 2008 at 238 Tcf, with producers specifically targeting the nation's promising shale formations for this energy commodity.
Geophysicists play an important role in the oil and gas industry as they help find underground oil and gas deposits by creating a clear picture of what is below the earth’s surface. Using physical methods (seismic, gravitational, magnetic, electric) they measure the physical properties of subsurface earth to detect or infer the presence of oil or gas. The most common way to create a clear picture of the earth's subsurface is through the seismic method whereby shock waves that are set off at the surface resonate through the earth, and the returning echo can be used to tell what is beneath the surface. Geophysicists are usually classified into three categories: acquisition, processing and interpretation. A strong geoscience, physics, or mathematics background is necessary for a career in geophysics.