The petroleum complex hydrocarbon compounds occur naturally in rocks under the Earth's surface. There is a main element is hydrogen and carbon from decomposition of organic substances a lot under tremendous heat and pressure.
Petroleum hydrocarbon complex Occurs naturally in rocks below the earth's surface. The main elements hydrogen and carbon from decomposition of organic substances, many under enormous heat and pressure.
Petroleum, hydrocarbon complex. Occurring naturally in the rocks beneath the surface of the earth, there are major elements are hydrogen and carbon from the decomposition of organic matter a lot under heat and pressure loads.