The oil field is a subsector of the petroleum industry that extracts oil and gas from the earth. It generally refers to the exploration, development, and production of oil and natural gas. The oil field can be divided into onshore, offshore, and deepwater.
Onshore oil fields are found near the earth's surface, while offshore fields are located in water that is a certain distance from shore. Deepwater fields are located at great depths below the surface of the earth.