►Petroleum engineers design and develop methods for extracting oil and gas from deposits below the Earth's surface. Petroleum engineers also find new ways to extract oil and gas from older wells.✦ ►Petroleum engineering is a field of engineering concerned with the activities related to the production of hydrocarbons, which can be either crude oil or natural gas. Exploration and production are deemed to fall within the upstream sector of the oil and gas industry. ✦ ►Exploration, by earth scient