How Was Crude Oil Formed Oil is one of the oldest resources on Earth. Together with natural gas it’s one of the byproducts of carbon. The origin of oil is based on a billion years long process may have started 65-200 Million years ago. The death animal and plant remains massed one over the other in a lots of levels, and involving the action of heat and pressure these remains have been separated from air for million of years. During all this time, a part of their organic material converted to crude oil, the death marine life into rocks. This …