Oil fields are regions of land saturated with petroleum as a result of geological activities. These geological activities result in the formation of reservoirs that contain oil, with geological features such as permeability, porosity, overpressure, and structure, making them suitable for harvesting. The process of finding oilfields entails exploration and exploitation, with seismic methods used to locate potential fields and the drilling of wells used to evaluate the dimensions and conditions of the fields.

Oil fields consist of the oil itself, the reservoir sediment, and the rocks that contain the oil reserves. The sediment acts as the physical barrier that separates the oil from the rest of the Earth's material, trapping it in place until it can be harvested. The rocks that contain the oil are porous and permeable, allowing oil to pass through them easily, and the overpressure of the Earth’s formation is responsible for keeping the oil in the reservoir.

The harvesting process of oil typically relies on heavy machinery to gain access to the oil reserves. This is done with the help of derricks, which are structures consisting of wellheads, drill pipes, and other equipment used to extract the oil from the reservoir. The crude oil is then treated in a refinery, which separates and refines the oil into a number of products such as gasoline and kerosene.

Worldwide, the oil industry is important due to its contribution to the economy and energy security. Oil fields are extremely valuable, and their discovery and development represent a major financial investment with potentially high future returns. To this end, oil exploration is a risky venture that requires skill and resources in order to locate and extract the oil from the fields.

In addition to its economic benefits, oil fields also play a role in the environment. Developing technology has allowed for more efficient and safer extraction of oil from fields, reducing the risk of pollution. Furthermore, oil field owners are responsible for ensuring that the fields are operated responsibly and that all laws and regulations are followed.

Overall, oil fields are an integral part of the global economy and energy security, and the production of fossil fuels is a major industry. As a result, the discovery and development of oil fields continues to represent a major investment, as well as potential financial rewards. In addition, the responsible extraction and use of oil provides environmental benefits, as well as economic ones.