H OW D O F OSSILS F ORM ? Fossil, mold, cast, fossil fuel

F OSSIL Any naturally preserved evidence of life. EXAMPLES – shells, bones, footprint, impression of a leaf, an animal’s burrow or even organism’s waste.

3 T YPES OF F OSSIL FORMATION 1- ENTIRE BODY ● Body dries out ● Trapped in a bog (thick swampy mud) ● Frozen ● Tree Sap

2- USUAL F OSSIL FORMATION Animal dies. Soft parts decay or are consumed (eaten by another animal). If the hard skeleton is buried in sediment it may slowly be changed into rock.

3- I MPRESSIONS Clam is buried in sediment. Sediment around the clam hardens. Animal soft parts decay and shell dissolves. Harden sediment around clam forms a MOLD of the clam shape. If sediment fills the mold and hardens a CAST of the original organism forms.

T YPES OF FOSSILS Any organism, bacterium, plant or an animal can become a fossil.

C HANCES OF BECOMING A FOSSIL Some are more likely than others to be fossilized. ● Hard parts like skeletons and shells vs. soft parts. ● Organisms that live in water vs. land. (Water offers more of a chance to be buried than land where scavengers can feed or weathering can occur. ● Energy in the environment. Calm lake vs. rough ocean water.

F OSSIL FUEL Energy-rich resources that form from the buried remains of once-living organisms. Three kinds of FOSSIL FUELS ● Coal ● Natural Gas ● Petroleum (oil)

F ORMATION Organism dies (plant/animal) Stored energy remains in cells of its body. Covered by sediment. Temperature and pressure caused by the layers above change the dead organism into fossil fuels.

COAL Swamp plant dies and sinks to bottom of the swamp where it decays. Decaying matter is buried under sediment, pressure and temperature increase. Bacteria and fungi help plants decompose or break down. Moisture and oxygen are pressed out leaving a high carbon concentration know as coal.

P ETROLEUM Protists (ocean organism) captures energy from the sun. Organism dies and falls to ocean floor. Buried by sediment, temperature and pressure build up. Overtime the remains are changed in petroleum and natural gas.

W HERE ARE FOSSIL FUELS FOUND ? Petroleum and natural gas – form from organisms that once lived in oceans – look where oceans once existed millions of years ago. For example – Texas, Saudi Arabia, Russia Coal deposits are found under sites of ancient swamps. For example – United States, Africa, South America