: Fossil refers to the type of material that animals and plants have turned to rock. Traces of prehistoric flora and fauna, such as carcasses, have been found in the form of sedimentary rocks or compounds that have been deposited underground or in solid layers of the earth's crust. Fossils of most living animals have been collected. In addition , many species ( biology ) have discovered fossils of fossils of animals and plants from the Ice Age, which are now extinct 3.4 billion years ago. Crude oil or petroleum (liquid gold) is basically a mixture of hydrocarbons and some other organic compounds. Of these, carbon and hydrogen are particularly important. To make crude oil usable, different parts of it are separated in a partial distillation method. The boiling point of different components present in petroleum varies. Petroleum Gas Petrol (Gasoline) Naphtha Kerosene Diesel Oil Lubricating Oil and Bitumen. Mineral oil is a chemical mixture of methane and naphthalene and a liquid hydrocarbon of aromatic order. The liquid fuel extracted from the earth is called petroleum. Data source Wikipedia