![W_logo_color_pos_RGB logo](/images/default-source/brand-portal/logo/w_logo_color_pos_rgb.png?sfvrsn=1a0a3c43_3)
A process whereby oil is recovered other than by the natural pressure in a reservoir. Refers to a variety of processes to increase the amount of oil removed from a reservoir, typically by injecting a liquid (e.g., water, surfactant) or gas (e.g., nitrogen, carbon dioxide).