Where do we find oil? In sedimentary rocks located between 7500 and 15000 feet underground.
The Process of Creating Oil We start with organic material (dead plants and animals) that accumulates and then is buried under later layers of soil.
Location of World’s Oil and Natural Gas The soil where the organic material is buried becomes a type of rock called sedimentary rock.
Location of World’s Oil and Natural Gas This rock must then be buried underground between 7,500 and 15,000 feet for a combination of heat and pressure to transform the organic matter to oil molecules.
Location of World’s Oil and Natural Gas Below 15,000, underground heat breaks the organic matter (and any oil) into natural gas. Above 7,500 and the rock hasn’t been squeezed and heated enough to break down the organic material.
Why Isn’t There More Oil? Normally in nature, organic material is recycled: dead plants, etc. become soil that new plants use.
Why Isn’t There More Oil? Even if the organic material accumulates and is buried, it may not be buried deep enough to convert it to oil.
Why Isn’t There More Oil? Even if organic material does get buried and converted into oil, it can then become more deeply buried and turned into natural gas.
Why Isn’t There More Oil? On top of this, the oil rich sedimentary rock can be pushed upwards, and through a variety of ways, the oil can leak out of the rock.
Why Isn’t There More Oil? Lastly, the rock has to have a certain amount of porosity, (microscopic holes and cracks) so the oil can flow.
Why Isn’t There More Oil? So even if geologists do find the right type of rock, it often doesn’t contain any oil, or extremely small amounts.
Location of Oil So only a few countries have ever had large amounts of oil; USA, Mexico, Venezuela, Nigeria, Russia, Saudi Arabia, Kuwait, and those countries around the Persian Gulf.
Location of Oil More importantly, only a few countries have had large amounts of oil that is easily and cheaply accessible: USA, Mexico, Saudi Arabia, Kuwait and those countries around the Persian Gulf.