Oil is extracted from the ground using the three techniques of primary recovery, secondary recovery and enhanced recovery. These techniques are applied to oil extractions on land and at sea. The extraction process varies in duration but uses the same methods to remove oil from wells of all sizes.
The primary recovery phase uses underground pressure to bring fluids to the surface. This technique relies heavily on artificial lift technologies to bring oil to the surface. Secondary recovery produces water to separate oil from its surrounding rocks. Enhanced recovery uses thermal, gas injection or chemical flooding techniques to extract and export oil and is used for reaching oil deep below the surface.