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Fossils. 4 Types of Fossils. 1. Body Fossils 2. Trace Fossils 3. Mold 4. Casts. Body Fossils. The entire body of an organism is preserved. For example… a small bug trapped inside tar ( Jurrassic Park)
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4 Types of Fossils • 1. Body Fossils • 2. Trace Fossils • 3. Mold • 4. Casts
Body Fossils • The entire body of an organism is preserved. • For example… • a small bug trapped inside tar (Jurrassic Park) - Herds of animals discovered in a tar pit (animals may have thought it was a watering hole, became stuck and died)
Trace Fossils • Portion of an organism preserved. • For example… • Footprints • Bones • Teeth • Animal poo • Nests
Mold Fossils • Mold fossils are made by an organism’s impression (imprint) in the sediment. • The impression then becomes packed with many layers of sediment.
Cast Fossils • Cast fossils are exact replicas of the original organism. • When the organism dies and becomes covered with sediments, the impression fills with water. • The water dries up leaving the minerals from the water behind. • The minerals harden over time and take the shape of the organism.