Oil.+where+does+it+come+from?

Brittney Journal #2 November 1, 2007

Where does it come from?

Oil and Natural gas come from the remains of single –celled plants and animals that lived in the sea 400 million to 500 million years ago. ( Natural gas was formed from the remains of land plants, as well). These remains were buried under layers of mud and rock subjects to the great pressure and high temperatures. Over time, they became converted into oil and gas.

While some oil and gas have seeped up to Earths surface, much is trapped underground in layers of porous rock ( rock, such as sandstone, with spaces in it) Underground sources of oil and gas are called reservoirs. Many reservoirs contain a combination of oil, gas and water. The gas is either dissolved in the oil or exists in a separate layer above the oil. Some reservoirs contain only gas.

The largest concentration of underground oil is in the Middle East. The greatest supply of natural gas is beneath Russia and other nations of the Soviet Union

Engelbesrt,Phillis, ed. U X L Science Fact Finder, Volume 2. Detroit U X L, 1998, Pg 249-251.