Plants leaves are often preserved as?

Most fossils are found in sedimentary rocks, those rocks produced by the accumulation of sediment such as sand or mud. Wind and other weathering conditions wash away sediment on land, depositing it in bodies of water. For this reason, fossils of sea creatures are more common than those of land creatures. Land animals and plants that have been preserved are found mostly in sediments in calm lakes, rivers, and estuaries.

The likelihood that any living organism will become a fossil is quite low. The path from the organic, living world to the world of rock and mineral is long and indirect. In the best conditions, fossilization will occur if an animal or plant dies and is quickly covered over with moist sediment. This prevents the animal or plant from being eaten by other organisms or from undergoing natural decay through exposure to oxygen and bacteria. The soft parts of an animal or plant decay more quickly than its hard parts. Teeth and bones are therefore more likely to be preserved than skin, tissues, and organs. Because of this fact, most fossils come from the time period dating to almost 600 million years ago, when organisms began to develop skeletons and hard parts.