Crude oil (In English: petroleum, from the Latin: petrus), also dubbed as the black gold is a viscous liquid, dark brown or greenish flammable, which is located in the upper layers of some areas of the earth's crust. Petroleum and natural gas derived from ocean microorganisms, plants and animals that died approximately 150 million years ago. The remains of these organisms to settle on the ocean floor, then covered by mud. Mud layer gradually turned into rocks because of the influence of pressure on top layer. Meanwhile, with increasing pressure and temperature, anaerobic bacteria outlines the remnants microorganisms and converted it to oil and gas.
