Crude oil is a naturally occurring fossil fuel that is formed from the remains of dead organisms (such as algae and zooplankton) that existed millions of years ago in a marine environment. These remains sank to the bottom of rivers and oceans and became buried in layers of mud, sand and rock. This organic matter provided carbon and hydrogen atoms, when subjected to intense heat and pressure underground over millions of years, combined to form the hydrocarbons found in crude oil.

What really happens to the plastic you throw away - Emma Bryce

Crude oil is pumped up from the ground or ocean floor in long pipes and sent to an oil refinery. At the refinery, the crude oil is heated over a furnace that separates the oil into different groups of hydrocarbons. Some examples are gasoline, diesel fuel, fuel oil. One distilled product is Naptha. Naptha contains ethane and propane and this part of the crude oil is used in making plastic.

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