Average Salary: $102,300 to $176,300.

Petroleum engineers help locate natural reservoirs of petroleum deposits. They work with teams of specialists to develop more effective, cost-efficient methods of petroleum recovery through the application of principles from chemistry, mathematics, engineering, and geology. There are three types of petroleum engineers who differ only by the stage of the drilling process that they are involved in. Reservoir engineers monitor the geological formation for the best strategic method of extraction.

Drilling engineers generate computer-simulated models of the drilling formation and equipment to ensure they use the best tools for the most effective method of extraction. Production engineers manage the interface between drilling and extraction by managing machinery and production costs.