Fossils

The scientific study of fossils is called paleontology.

 

The fossils are remains of plants and animals, they are the evidence of their existence that have been preserved in the rocks layers of the earth. Fossils may be bones, shells, leaves and branches. Many rocks sequences contain a large numbers of fossils, conditions prevailing  at the time  have to be just right  to ensure preservation.

 There are other fossils called fossil fuels that include petroleum, coal, and natural gas. Fuels are created by the fossilisation of plant or animal remains. Oil and gas often found together. 

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