How are fossils formed?

Fossils form when an animal or plant dies in water or nearby places. The water insulates the remains from many of the elements that contribute to decomposition. For example, when an animal has died of old age at the bottom of the sea, bacteria consume the soft body parts, but leave the hard exoskeleton intact. As time passes, sediments bury the exoskeleton. As the sediments continue to pile on, the lower layers become compacted by the weight of the layers on top. Over time, this pressure turns the sediments into rock. As the continental plates move around the Earth, crashing into each other, mountains are formed. Former sea floors are lifted up, and become dry land. Thanks to the movement of the plates, fossils will come closer to the surface and nearer to discovery by some fortunate fossil hunter. Fossils are finally revealed through the forces of erosion.Though there are millions of fossils that have been discovered and millions more waiting to be discovered, fossilization is a rare occurrence. Soft bodied animals and plants that have no woody parts are rarely fossilized.